1
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2417-Washington
Assistant
D.C.
20013
Area Code 703-235-8198
about
this
Ground-Penetrating Radar
Resource Managers
Jerry D. Greer
Project Leader
Nationwide
Forestry
INTRODUCTION
Applications
A Review
Program
for
NFAP
radar GPR systems permit us to
Ground-penetrating
look into the earth and see what lies beyond the
limits of our normal vision.
GPR is as its name
suggests a radar-based system that transmits a
This beam is
signal or beam into the earth.
interfaces.
The reflected
by subsurface
signals
can be analyzed to identify these features which we
can neither see nor touch.
GPR also is called
interface radar ground profiling radar
or electromagnetic subsurface
The
profiling.
has been available
since about 1970.
technology
reflec-ted
sub-surface
WHAT GPR
IS
This
is based on
technology
impulse radar systems.
type of radar system repeatedly
radiates very
short electromagnetic
The
pulses into the earth.
pulses are radiated from an antenna
that
is set
close to the ground.
This
The
system operates similar to acoustic profiling
The pulses each
systems.
lasting only a few
billionths of a second
are reflected
from the
The
ground surface and from subsurface
interfaces.
reflected
signals are detected
and
interpreted
chart recorder.
displayed on a continuous-strip
Depending
characteristics
upon the electromagnetic
of
the geologic material the
depth to reflecting
discontinuities
can be calculated
to
accurately
within a few inches.
WH ER E G PR
STARTED
Like
many remote sensing systems GPR probably owes
beginning to research conducted
by the military.
They have been interested in developing
the ability
to detect
land
mines and enemy tunnel works
For
many years now this technology
has been used to
profile ice thickness
its
4.
1.
Researchers
in the field of mine safety also have
worked to develop techniques
that permit the routine
use of GPR to see clay veins and voids from 200 to
400 feet into otherwise
solid limestone
6.
1
%
Figure 1.--The relationship of bedrock to the ground surface can be
This profile from near Salem New Hampshire
mapped using GPR.
The
darkest part of the
reveals a very undulating bedrock surface.
80 feet.
of penetration
here exceeded
The depth
scan is the bedrock.
a--Tunnel
Between
nt
oct
Face
and
Concrete
5
radar can be
2.--Ground-penetrating
inspect critical cement structures
tunnel
such
as dam facings railroad and auto
In
this example GPR
walls
and a5uaducts.
walls
of a
used
to
examine the concrete
was
The boat-wake
railroad tunnel
in France.
pattern is a void within the solid rock
behind the tunnel facing at the top of this
back into
This
void
is about 5 feet
figure.
Liner
Feet
Figure
used
the
to
L
Pe
rock.
2
5L
of
ectivc
1J
tration
3.--In advance of construction
features of the
subsurface
be examined
to
locate potential problem areas or hazards.
earth
can
In this printout
of the recorded
GPR
data a series of nearly
vertical
Designs can be modified to
parallel fractures stand out.
accommodate such
features or another
site may be selected.
Figure
WHAT G PR CAN
GPR has many routine applications
and
researchers
continue to find and develop new ones.
Compared to
standard radar systems where distances involved can
be extremely long
the first maps of Venus were made
radar systems the distances
using Earth-based
involved in GPR are relatively short.
Depths of
10 meters are common.
Research
indicates that
impulse radar systems could penetrate to 10
in certain kinds of rock or mineral
kilo-meters
24.
penetration
depth of a system is a function of
of the geologic
effective
materials
conductivity
The conductivity
is primarily
being evaluated.
determined
content of the material and
by the water
of
Other factors
salts in solution.
quantity
by the
limit
the
of
that
are the
depth
penetration
and
the
and
of
the
material
density
geologic
of
the
transmitted
waves.
frequency
electromagnetic
The
the
tempera-ture
3
be
can
of highway pavements
inspections
Figure 4.--Nondestructive
This figure shows
made at any time during the life of the roadway.
radar scan made from near a.pavement edge ac rocs the centerline to
a
the opposite edge.
The
reinforcing wire mesh forms a prominent
The
the middle of the
pavement joint is at
image.
pattern across
the center of the.highway.
geo-logic
of
characteristics
Because the electromagnetic
the potential depth of
materials vary widely
with any accuracy.
cannot be predicted
penetration
subsurface
with
profiling
Work done
electromagnetic
reached
of
75
feet
was
indicate
that
a
depth
systems
of
delta
in a Massachusetts
glacial
composed
sands.
The depth of an Antarctic
water-saturated
other end of
On the
measured 230 feet.
ice shelf
reached
in wet
of
5
feet
was
the
only
scale a depth
in
be
reached
open
clay and less than a foot could
When rocks have electrical
sea water.
character-istics
3.
like
more could
of
that
dry
be expected
4
sand depths
of
100
feet
or
S
5.--In this radar scan printout notice the
in this concrete
out
This
scan
was
highway.
radar unit along the centerline of the highway.
A
in the
concrete
also is easy
to see.
Figure
stand
USESforGPR
the rebars
way
made by towing the
transverse joint
During NASAs Apollo program an impulse radar system
was used to probe the
subsurface
features of the moon
For the Forest Service
uses will be closer to
home and the technology has already been applied to
For several applications GPR seems
many problems.
to be the most effective
and most
efficient way to
data
about
subsurface
features.
gather
specific
Table 1 contains a list of many current applications.
5.
prob-ably
radar is a potentially
useful tool
Ground-penetrating
for resource managers.
Some potential uses of GPR
Readers of this article
are listed in table 2.
could add new ones to the list.
5
Table
1--A partial
list
strata
Geological
profiling
Bedrock
mapping for subway
Rock
Void
mapping
fracture
detection
for
air
airfield
evaluation
of
Fault
mapping
for
detection
Crevasse
San
for
of
for
tunnel
current
some
applications.
excavation
and
other
highway
excavations.
and
safety
other
purposes.
Base
Navy
bases
New
Brunswick
pavements.
Andreas fault.
projects.
rapid
on
glaciers.
salt domes.
profiling
for
mine
and
other
operations.
profiling
safety
Detecting lost oil well
or water
well
casings.
River
and
lake
bottom
profiling.
and
Mapping
Borehole
Ice
thickness
for sea and
river
profiling
and
snow
measurements.
depth
Permafrost profiling.
masses
of ground
ice.
Locating
large
Airborne
ice.
ice
draft
Iceberg
profiling.
Sinkhole
in Florida
and
other
States.
prediction
Peat
in Europe
and
the United
States.
profiling
Measuring
Buried
Tunnel
coal
beds
Pavement
Reinforcing
rock
strata.
cable
thickness
Perimeter
and
mapping plastic
military activities.
and
pipe
detection
and
voids
under
metal.
or
pavement.
surveillance
for
security
bar locating
at
nuclear
tunnels
plants
mines
and
and
cables.
construction
other
sites.
Submarine
pipe
and
cable
location.
detection
metal and nonmetal.
Hazardous waste
mapping at Love
Canal
and
Michigan.
Contamination intrusion
mapping.
features.
Archaeological
surveying
mapping subsurface
Mine
hidden
Locating
chambers
water-filled
Detecting
Treasure
in
the
voids
in
of
great
pyramids
coal
mines.
Egypt.
hunting.
bed
profiling
Railroad
leak
detection.
Pipe
Oil under
ice
detection.
Buried
detection
in
body
Explosive
mine
Detection
of
England.
by British
detection
nondetonated
mortar
in
Navy
shells
and
Islands.
armaments in
Falkland
other
San
Diego.
Table
2--Some potential
Evaluate
visitor
Evaluate
hazards
hardrock
Evaluate
Locate
unknown
by people.
Locate
and
Locate
new
Locate
lava
uses
for
Inspect
Inspect
Evaluate
antenna
in caves
to guided
tours.
open
to the public
in abandoned
mines.
tunnels
on Forest
roads
and
highways.
mine
tunnels
in
potentially hazardous
management.
caves for management
information.
and
features
in caves
rooms
tunnels
areas
frequented
map
tubes
in
volcanic
being
managed.
areas.
for
horizontal
drilling
projects.
land
potential
slip areas.
foot
trail
and
horse
stability.
timber
haul
roads
for compliance
standards.
with
use
special
rights-of-way and easements.
geologic
conditions of proposed
foundations
of
and
other
towers.
Make
better
contracts.
Inspect
resource
in
safety
Locate
perched
water
tables.
Evaluate
water
potential
production
Plan
tile drain
systems.
Locate
Evaluate
GPR
cost
electronic
steel.
reinforcing
Evaluate
proposed
or leak
spots.
estimates
site
stock
for
antenna
water
trenching
projects
foundations
tank
sites
6
to
for
prior
the
detect
line
electric
to
proper
potential
letting
use
of
trouble
C
is
Bottom
of
Surfa
c.pcr
t
I
radar is used
Figure 6.--Ground-penetrating
utilities buried beneath streets
to locate
This
figure shows how
or concrete
pads.
located
buried utilities can be accurately
reinforced
are beneath heavily
even when they
concrete.
AVAILABILITY
and
training currently are available from
Equipment
Geophysical
surveys routinely
private businesses.
use GPR at relatively shallow levels--to about 15 or
applica-tion
20
Simple systems cost approximately $15000.
powerful systems with more potential
The services
can cost
as much as $43000
may
contracted.
feet.
More
be
SUMMARY
radar is an available technology
Ground-penetrating
with many current and potential applications.
Research
is continuing
to improve the depth of
The systems available
present an
data about subsurface
method of gathering
features.
pene-tration.
alterna-tive
7
REFERENCES
1.
Campbell
Profile
K.
Sea
Radar.
Impulse
2.
Cook
J.
Bituminous
1079-1085
A Continuous
Thickness By
31-44 1974.
and A. S. Orange.
and Freshwater
Ice
Polar Record 17106
J.
Ice
of
C.
Coal
Electrical
1970.
Samples.
1970.
Properties
Geophysics
356
of
Continuous
Geophysical
Survey Systems Inc.
Subsurface Profiling By Impulse Radar.
Geophysical
Survey Systems 1974.
3.
4.
Pittman
W.
E. Jr.
R.
H.
Church
W.
E.
Webb
and J. T. McLendon.
Ground Penetrating
Radar A
Review of its Applications in the Mining
Industry.
U.S.
Bureau of Mines Information Circular 8964
1984.
5.
Porcello
System.
6.
L.
J.
Proceedings
Meyers.
Personal
1984.
SUGGESTED
READING
The Apollo
IEEE
626
Lunar Sounder Radar
769-783
1974.
communication
Novenber
8
of Impulse Radar to
Ulriksen C.
Application
Civil Engineering.
Geophysical
Survey Systems Inc.
of
Lund University
Technology Sweden 1983.
1.
EFN
8
Lost River Ranger Station-
i
New Ground
Wilden W.
Architect
4
Region
INTRODUCTION
Moffett
of
earth
fall of 1982 when the first shovel
turned for the new Lost River Ranger Station on
the Challis National
Forest at Mackay
Idaho new
of
ground was broken on more than the construction
building.
In
the
was
a
River is the first office in Region 4 to depend
as
a
Designed
largely on solar energy for heat.
passive system the entire south wall of the office
is enclosed
in a greenhouse.
Energy from the sun
traveling through the greenhouse is absorbed into a
blocks
of
concrete
special collector wall constructed
Lost
early review of the building and its
From left
Exhibits
exhibits.
to right
Designer Mel Alexander Forest Engineer Dale
Armstrong and Regional Architect Wilden
Moffett.
An
9
Lost
River District Ranger Office
viewed from the southeast.
The
greenhouse
helps to provide solar heat--the primary
source of heat for this building.
The
view of the special
collector
greenhouse during construction.
A
wall
and
laid on their sides.
Blinds inside the greenhouse
help control the amount of energy collected in the
daytime and lost at night.
three-quarter-HEATING
PASSIVE
SOLAR
SYSTEM
system is passive except for the
horsepower blower which is about the same size
blower in a home furnace.
The air within the system
is forced to flow serpentine
fashion through the
collector wall so that
it passes over
all of the
solar-heated
surfaces.
The heat from the sun that
has been absorbed into the concrete
block
is
to the air which
then is channeled
down into
a floor duct
in the basement.
The
trans-ferred
From the duct
the air flows around the perimeter of
the building at the base of the basement walls.
Special furring on the exterior walls allows the
solar-heated
air to wash the entire interior surface
of the exterior walls thus
transferring the heat
back into the solid masonry storage walls.
These
walls
are heavily
insulated on the outside to
storage
reduce heat loss from the building and to retain the
stored heat.
The heavy mass walls at the buildings
perimeter storing the solar heat are radiant walls
and become the heating source for the building.
solar system carries the trademark Xen-Wall.
was developed
concept
by Xenarcx
Inc.
and
into the building
Sparks Nevada
incorporated
design by the Regional Architect.
This
The
design
10
A view of the entrance.
A small portion
the greenhouse
a
dynamic part of the
buildings solar system shows
BACKUP ELECTRIC
HEATER
at
of
right.
The backup heating system is a small
15-kilowatt
electric
heater mounted in the duct system.
When
the
solar system cannot provide all the needed heat
for the building the heater turns on and generates
heat
for the mass storage walls.
This
supplemental
differs from most solar systems.
The backup
is not
an independent
heating system but a very-low-cost
extension of the solar heating system.
Another departure from tradition in Region
4
involves
the design of the
reception area and
exhibits.
Former Interpretive Service Graphics
Designer Mel Alexander in cooperation with Regional
Architect
Wilden Moffett and Forest personnel
coordinated the design and decor.
These areas were
included during building construction
rather than
added at a later time.
Colors wood trim and
materials in the counter and exhibits were planned
to provide
a
warm attractive atmosphere for visitors
and
The exhibits include a backlighted
employees.
visitors to the
to introduce
map and other panels
District and to its resources.
These exhibits were
designed to fit in with finishes and the unique wall
construction
of this building--a difficult
task
if
planning had been left to a later time.
Ranger Jim McKibben feels that the coordinated
planning for the entire building has improved service
In addition
to the visitors.
the new building stood
undamaged
through the Challis/Mackay
earthquake
in town suffered heavy
while other masonry buildings
damage.
11
ROOF
WALL
FINISH
NOT SHOWN
WALL
FURRING
FRAMING--soup
FLOOR
OFFICE
SPACE
MASONRY
WALL
ERE
1HE
GREENHOUSE
SOLARIUM
Im.
tiI
CONC.
Uo
1
FLOOR
CONC.
FDN.
BASEMENT
WALL
LOST RIVER RANGER OFFICE
GREENHOUSE
COLLECTOR
WALL
u
ý
Arrows indicate
section through
greenhouse at the
A
WINTER
PERFORMANCE
collector
south side of
the
path of the solar-heated air
gives up its heat energy to the masonry
storage walls on the north east and west
sides of the building.
as
wall
and
the
building.
it
in a very frigid winter setting.
during the winter for nighttime
On many winter
temperatures to drop below -30 F.
days temperatures do not rise above 0 F.
The
heating degree days at this site vary from 9500 to
9900 for comparative purposes the winter heating
about 6000.
degree days in Ogden Utah average
Mackay
It
is
is
located
common
The records after two full seasons of operation
show that the solar system is contributing
about
60 percent of the heat for the building
2
heating load
seasons
Energy consumed
unit
by backup
Total
equivalent
energy
contributed
by solar system
Total
12
123400
48900
kWh
kWh
74500
kWh
The
Because of some
building is alive and well.
the first winter all employees
problems encountered
did not keep as warm as expected.
After these
were
identified
and
corrected performance
problems
the
second winter was very acceptable.
UTILITY
SAVINGS
simi-lar
initial cost
of the building
including
system was approximately $30000 more than
The
the
solar
a
construction
and
building with conventional
A conventionally
office of the
constructed
heating.
same size would have a heating load of approximately
154000 kWh.
Using current electrical rates of
$0.04 per kWh we project that the additional cost
of construction
will be offset by utility savings in
This payback
about 14 years discounted payback.
time would be significantly reduced
in a milder
climate and in an area where power rates are
to those found in the Rocky Mountain
area.
compar-able
FOR MORE
INFORMATION
If you have questions
or desire more information
about this project or about Xen-Wall
solar heating
Wilden
Moffett
in
the
contact
systems
Region 4
Office.
Regional
IIII
EFN
13
Transfer-A
The Technology of Technology
Blueprint for Success
Connie Connolly
Technical
Information
Office
Washington
INTRODUCTION
The
Engineering
Road
and
the related final
to Regional
Foresters
Specialist
Technology
Improvement
Program
action plan which were sent
on April 18 1986 by Deputy
Chief Cargill focused on technology
transfer
as a solution to many of our problems.
For most of
TT
is
still
nebulous
term--an
a
us however
For Engineering
it must become
a
goal.
reality.
TT
intan-gible
The
to make TT a reality is
expected to be more productive--in
resources.
change and dwindling
Look around.
are shrinking personnel and
Budgets
resources are being spread thin.
Most of us find
ourselves being asked to take on new
without
the resources necessary
to do the
To
meet
this
job
challenge--not just today but in
the next decade and
next century--we have to adapt
to changing
circumstances.
major
reason
that we are now
an era of rapid
we
need
activities--often
effi-cient
transfer is a tool--not just a floating
Technology
can help us meet challenges.
It can
concept--that
us
reduce
costs
and
it
lead
help
can
to more
of personnel
budgets materials
management
and
natural resources.
It
can allow us to pool our
and
eliminate
efforts.
knowledge
duplicated
The
Forest Service has been attempting
to transfer
for
with
but
technology
some success
years--and
until now we have been concentrating
efforts
on
our
results applied by our cooperators
getting Research
the
public and field units.
tech-nology
need to expand our efforts and make
transfer a tool that Engineering managers and
technical specialists can understand
and
If we
use.
are to achieve
efficiency and provide more services
We
now
15
we must look for accept
and
share not only new
innovative
ideas but existing tangible methods
tools that will help us be more productive.
or
or
Most
of
us are or have been
involved
in some form
TT project.
Weve all had ideas or seen a tool
demonstrated
that we just know would make others
work easier if we could just get them to try it.
Or weve had a problem that we knew there had to be
a solution to--we
find someone else
just couldnt
who had faced a similar problem.
Some of us even
have TT as a performance element and weve
all tried
to convince
a
group or an individual to support a
even that was a technology
transfer effort.
concept
of
a
under-standing
This article is meant to help you take the giant
to
leap from knowing TT simply as a concept
TT as a tangible tool that you can then
to
improve
your or your
units efficiency.
use
Lets
see if we can build a blueprint that will help
us understand
the
of technology
technology
transfer
and
how we can make it work so that we can attain
the benefits
of
reduced
costs and more efficient
management.
UNDERSTANDING
The
first thing we
important terms.
need
is
a
common
understanding
of
nderstanding
tech-nology
Many
times we think that we are transferring
when we are merely transferring information.
INFORMATION
is KNOWLEDGE
and
INFORMATION
TRANSFER
is simply
MAKING THAT KNOWLEDGE AVAILABLE
TO OTHERS.
On the
other hand
TECHNOLOGY
is APPLIED KNOWLEDGE
and TECHNOLOGY
TRANSFER
IS
THE
ART OF NOT ONLY MAKING PEOPLE
AWARE OF TECHNOLOGY
BUT
GETTING
THEM TO USE IT.
When they accept
and
apply the technology
transfer has taken
technology
place.
16
OPEN WORK
ENVIRONMENT
The next thing we need is to create an open work
environment
that will allow technology
transfer to
take place.
There are several points we need to
consider here.
Open
Work
Environment
Change
The
first
We mentioned earlier that we
change.
forced
do
to
a better job
in an era of
being
and
We have to be
rapid change
dwindling
resources.
able to manage that change
in fact
we need to
cultivate it if it will help us do a better job.
We
cant afford to waste a dollar or a minute doing any
work that
is not
necessary or doing work in any way
that doesnt allow us to maximize our resources.
To
make change work for us instead of against us we
have to change our outlook--the
way we view ourselves
and our work environment.
Once we do well be able
to
make the real changes--the
sharing of better ways
of doing
that
things
transfer can bring
technology
about.
is
are
Change
Open
Work
Environment
others to change their way of doing
have to change first and thats not
We all react differently
to change.
always easy.
Some of us actively seek out better ways to get our
work done.
Most of us dont seek better ways but
we will change if we can see the benefits
of doing
so.
And then there are a few who resist change.
But we all have to try.
We have to create a work
environment
that welcomes
change.
If
we
want
something
we
17
fI
Innovation
Innovation
is the
second thing we need.
We can
foster innovation
innovative
ourselves and
by being
others to be innovative
and
share
by encouraging
information.
The best way to do this is not
to
the
flow of information or ideas.
Restricting
the flow of information not
only stifles creativity
but
increases the likelihood that information will
be held until its obsolete.
over-manage
Change
Innovation
Open
Work
Environment
Risk
This brings us to the third element--risk.
When we
foster a more open work environment we risk some
loss of power and
control.
Staff who are better
informed will become more independent
and will
rely
on us less.
But this is really more a perceived
than an actual risk.
The greatest risk--to
or to an organization--comes
from stifling
the flow of ideas and information the
risk that the
information or technology
we should be using now to
operate more efficiently will be missed and needed
Thats
change will not take place in a timely way.
the
risk thats not worth taking.
As for the
risk of
carrying out an actual technology
transfer there is
none if were operating
in an open work
practically
environment and if the transfer is well planned.
indi-viduals
Change
Innovation
Open
Work
Environment
Risk
18
BENEFITS
We
can sell the concept
of the open work environment
ourselves and others by enumerating
the benefits.
mentioned the two most important ones
costs and more efficient management
of
resources.
Well there are also four less tangible
but
still very significant
benefits--a better
informed and motivated staff a more cohesive
recognition for successful
technology
transfer efforts and the challenge of discovering
and putting
into practice ways to do our work more
efficiently.
earlier--reduced
to
We
organi-zation
Benefits
More
Reduced
Efficient
Costs
INDIVIDUAL
TECHNOLOGY
TRANSFER EFFORTS
Management
we have done so far is set the stage
for an
that will encourage
a free
open work environment
flow of information technology
transfer and the
The next
adoption of new ideas.
thing we need to
discuss is how to succeed in specific technology
transfer efforts.
What
Individual
Technology
Transfer
Efforts
There
1
2
3
Plan
are three important
How
to
How
and
plan
a
where
areas
technology
to
How to choose the
transfer media.
find
we
need
to
consider
transfer.
useful
technology.
most effective
technology
transfer is going to happen it has to
technology
We could argue that if we have that
planned.
been talking about
open work environment weve
wouldnt technology transfer just take place on its
free exchange of information and ideas
own--through
If
be
19
this will happen.
For example when
Occasionally
someone started using stick-on notes someone else
saw them and started using them and now most of us
wouldnt be without them.
But most technology
transfer efforts involve a technology
that
is not
as
easy to sell as stick-on notes.
Plan
Individual
Technology
Transfer
Efforts
need to put together
transfer
a technology
an
outline
of
how
intend
to
we
plan
carry out a
and
what
it to
specific transfer
we expect
It
doesnt need to be long or
It
should address the following
functional.
So
we
accom-plish.
elaborate--just
areas
If we
state the problem clearly
choose an effective
technology
to solve it.
On the other hand
if we already
know
about a technology
that
could be useful to others we
need to define the problem so that others will know
why they should adopt that technology.
Define
it
will
Problem.
easier to
the
be
Tech-nology
Technolo
To Be Transferred.
broad term and the technology
we are
trying to transfer may be something as specific and
easy to describe as a piece of equipment or something
a little more involved
like a process or method of
working.
Identify
is
the
a
If we dont know
or
Identify the Intended Users.
have only a fuzzy idea o
who our users are we
wont know how to get them interested.
To win them
over we have to know them--that is we have to know
their interests and needs.
We have to view our
transfer effort from their perspective.
technology
Establish
specific
them and
the Objectives.
We need to establish
objectives to design a plan that will meet
the results of our efforts.
to evaluate
20
Select Appropriate
Transfer Media.
Selecting media
is crucial
to
trans er because it is
technology
Because media
through media that we sell our ideas.
are such an important and
little understood part
of a successful
technology
transfer they will be
discussed
in more detail later.
Select a Team
Team Members
and Assign
Implement the Transfer
We
Responsibilities.
usually cannot
do it alone.
The team consists of those people with
the special skills and
needed to help
knowledge
the
transfer.
The
team can be any size or
implement
it
takes
to do the
configuration--whatever
job.
Plan
To
Costs.
There
1
four main considerations
transfer
the
cost
costs
planning technology
the
the
transfer plan
implementing
technology
cost of implementing the technology
the
on
ground
annual operating
costs and any other costs
to the particular
whether or
technology and
not
the necessary
resources--personnel funding and
available.
After we have estimated
materials--are
all the costs we need to estimate
that
the benefits
be
and
will
realized once the technology
is accepted
used.
If the benefits
outweigh the costs and the
resources are available we should go ahead with the
transfer.
the
are
3
speci-fic
in
of
2
4
Determine How the Technology
Transfer
Process Will
Be Evaluated.
We
need to evaluate our effort so we
know if our objectives are being met.
The lessons
learned in our evaluation
also will help us to do a
better job next time.
Sources
transfer efforts to
technology
we not only need to plan them but we need
succeed
to know how
to find transferable
technology.
By
transferable
technology we mean technology
helpful
to end
users.
If
we
want
our
Plan
Individual
Technology
Transfer
Efforts
21
Sources
Sources
of
Technology
Known
Technology
within
the Forest
New
Service
Technology
through Research
and Development
Figure
1.--Sources
External
Technology
of
technology.
develop-ment
avail-able
transfer-able
The
available through research
technology
and external sources
is important but
accounts
for only a small fraction of the technology
for transfer figure 1.
Almost all
is already
known and being used
technology
somewhere in the Forest Service or forestry community
to solve problems or do work more efficiently.
and
can
Large numbers of our people are innovative
be found tapping internal and
external sources.
They have the knowhow
they now need to make the
effort to share it.
So
we need to look
in our own backyard
or in the
next District Forest or Region
before we look
outside to come up with a solution to a problem.
Somewhere somebody in the Forest Service probably
has a technology--a
tool a system or a
could solve the problem.
On the other hand
we may have an innovative
of
doing something--a
way
that
Shouldnt
technology
nobody else knows about.
others profit from our ideas and experience
And
shouldnt we profit from theirs
For that matter
couldnt we also benefit from learning about each
others mistakes and not duplicating each others
technique--that
efforts
We could say then that the best place to find
needed technology
is to find someone
who has faced
the same problem.
We have to put
the word.
We
out
each have a network of contacts and they have other
contacts and associates.
But suppose were faced
22
with
That
our contacts.
the Forest Service.
a problem-oriented
data base to
the
contacts
we
all
have
into
a Forest
integrate
Service resource--one that would put people with
work-related
problems in touch with people who have
dealt with similar problems.
a
problem
new
still doesnt
mean
We need to develop
Media
to
us
and
its new
to
to
tech-nology
audi-ences
Perhaps the most important thing we need to know is
how to select the right medium or media to sell our
When we transfer
to intended users.
technology
we need to sell--that is to actively convince
the
others to adopt our ideas.
We need to get
attention and hold it.
Plan
Individual
Sources
Technology
Transfer
Efforts
Media
Most of us dont know which medium is best when it
comes to convincing
users to adopt new or different
For
this
technology.
reason the following deals
with the relative degrees of media effectiveness.
effec-tive
Personal contacts are more than 10 times as
as print media in transferring
see
technology
In the
case of the other two
figure 2.
and
electronic--users
find them more
than twice as effective
as print media but
they
still fall far short of personal contacts
in overall
The people we need to reach are
effectiveness.
influenced
more than twice as much by personal
contacts as by all other media combined.
media--audiovisual
Personal
Contacts.
There
are
six
and t e most effective
categories
and demonstration
projects figure
because we have the
more effective
23
personal
by
3.
far
contact
are
Peers
advantage
peers
are
of
Electronic
Problem-Oriented
Electronic
Bulletin
Data
Boards/
Conferenc
Systems
Programmed
Instruction
Bibliographic
Data
Figure
Base
Mail
X
Bases
4.--Electronic
media.
Bulletin boards or conference
systems are
the
volunteers
who are
because
effective
very
contacts
in
various
disciplines
to
serve
as
willing
have worked on the problem you are trying to
may not
solve and may not know anything about it.
instruction has its place but lacks the
contact that an instructor can provide.
to research
data bases provide citations
technical journal articles
and
reports and scientific
but
they are difficult to search without
by subject
and
seldom
specialized training and experience
solutions.
with
Copies
timely
practitioners
provide
of cited
reports and articles are often difficult
address
and
to obtain
frequently dont effectively
media.
not
Pro-grammed
per-sonal
Bib-liographic
the
issue.
5
can
media figure
Audiovisual
videos are considerably
and films and
be effective
better than the other two--slide/tape
programs and
slides or vugraphs.
Audiovisual
Media.
audio-visual
aside Forest Service
could
be much more effective
presentations
than they are if we would
seek professional help in
them.
When we think about the importance
developing
of
contact
again we see that audiovisual
personal
make
able
to
a direct
media are
appeal to a broader
with
the
audience
able
to hear a real
audience
in
and
watch
a
real
even
technology
see
face
voice
audiovisual
Used
at
their
action.
best
can both train and motivate.
Relative
effectiveness
presenta-tions
stand-point
transfer
Print Media.
From the technology
and
technical publications
journals figure
than
effective
newsletters
memos
a
little
more
are
but
we
can
and
as
see
and
laws
regulations
reports
25
6
Audiovisual
Print
Technical
Publications
and
Journals
Newsletters
Memos/
Laws/
Films and
Reports
Regulations
Videos
Slide-Tape
Slides and
Figure
Vugraphs
5.--Audiovisual
Figure
media.
6.--Print media.
print medium is the least effective
means of
users
to
new
times
encouraging
technology--10
accept
less effective
than personal contacts and only half
as effective
as either the electronic
or audiovisual
media.
the
medium
be
useful
when it
can
But
print
is used to complement
other media--especially if a
greater effort is made to tailor print materials to
the needs
of
intended
interests and perspectives
users.
the
Now
that we know how effective
personal contact is
in persuading
intended users to adopt technology
figure
we can say that we should strive to make
informal as
any medium we use as personal and
After all we have to consider the intended
audience their location and availability of
Often we will want to combine media to increase
effectiveness.
For instance we say that workshops
are one of the least effective
personal contact
but if we organize a workshop that features
possi-ble
resour-ces
7
cate-gories
inter-action
demonstration project and plenty of peer
then we have an effective
media set
about
bring
transfer.
good technology
a
that
When
can
we are attempting
especially
important complex
technology
transfers especially those that involve
different groups of users with sometimes competing
we need to consider
using outside
concerns
to help us design a technology
transfer plan
and develop
its major components.
BENEFITS
consul-tants
tech-nology
benefits to be derived from individual
transfer efforts are the same as those
resulting from the open work environment--reduced
costs and more efficient resource management.
The
26
I
Degrees
Relative
Technical
Publications
and
of
Media Effectiveness
Journals
Newsletters
Memos/
Laws/
Peer
Contacts
Reports
Regulations
Films and Videos
Slide-Tape
Slides
and Vugraphs
Problem
Oriented
Electronic
Bulletin
Data
Base
Mail
Boards/
Canferenc
Systems
Programmed
Instruction
Data
Bibliographic
Bases
Meetings
..
Workshops
On-the Job
Formal
and
Groups
Demonstration
Training
Projects
Training
effec-tiveness
Figure
SUMMARY
7.--Relative
detailed.
degrees
of
media
all the elements we
sum up by saying that
both
to
create
and
need
our open work environment
to make our individual
transfer
efforts
technology
to our intended users combine
to form
acceptable
the
of
transfer.
We need to
technology
technology
understand
this concept
if we are to make successful
transfer a reality in the Forest Service.
technology
We
can
with a small
technology
step--understanding
transfer what it is and what it does.
Then we
learned that there are two equally important factors
that
combine to ensure successful technology
transfer.
We
began
The first factor is the open work environment
in
which ideas and information are exchanged freely.
We
can create this environment--through
change
risk.
innovation and accepting
The second factor
transfer efforts.
is
We
effective
make our
preparing and following a
sources of useful technology
effective
media.
by
individual technology
transfers effective
plan knowing
and
choosing
the
the
most
efforts--combine
tech-nology
When these two factors--an
open work environment
effective
individual technology
transfer
we have a blueprint for a successful
transfer program figure 8.
Now
and
it
is up
to you.
You know what your goals are
what the pressures are.
You know how much you
transfer
Good technology
expected to perform.
can help you.
Together we can make it work.
and
are
27
Blueprint for Successful
Technology Transfer
nderstending
Change
Open
Innovation
Work
Environment
Plan
Successful
Sources
Individual
Technology
Technology
Transfer
Transfer
Program
Efforts
Risk
Media
Benefits
More
Reduced
Efficient
Costs
Management
tech-nology
Figure
The
for
we
SLIDES
8.--Blueprint for
transfer.
successful
of
transfer
technology
technology
success.
We need to accept
it and
afford not to
is
a
use
blueprint
it.
Can
EFN
Note
A set
of 35-mm slides similar to the
illustrations contained
in this article were
distributed to each Regional
Office by WO-E Deputy
Director Furens 7100 letter dated May 30 1986.
For more information contact
Connie Connolly on
235-3111.
28
I
RipEm
Muscles-Case
IRPM Use in the West
Flexes
Studies of
Its
Wallace
R.
Cox
Regional
Transportation
6
Region
Analyst
as a long-haul
for
Designed
eighteen-wheeler
handling heavy cargo the Integrated Resources
is proving
its ability to
Planning Model IRPM
like
between
a cross
a sports car and an
perform
all-terrain vehicle.
Built on an ADVENT chassis
IRPM has a retooled drive train and a beefed up
transhipment suspension for handling rough
curvy
mountain roads it is slipped into a classic body
and comes complete with a slick personalized
users
guide.
5
INTRODUCTION
The mixed-integer mathematical
Integrated Resources
Planning Model IRPM originally was designed to
issues for large
address resource and transportation
area plans and Forest planning simultaneously but
as analysts became familiar with the model they
found that it could be used in a variety of ways.
Successful
of the model to road system
applications
have led to discoveries
of even more
management
comprehensive
potential uses such as developing
management
plans for annual maintenance
programs
exploring tradeoffs between traffic service levels
share maintenance
analyzing commensurate
construction
cost recovery schedules and
developing
multiyear capital investment programs.
In each case
alternatives are easily developed
under a variety of program budget level constraints.
establish-ing
exam-ining
IRPM
Further tests are now being conducted
to link
with the Aggregate Transport Model
Since
Transagg
currently does not have any means of
network efficiency in terms of operating
costs
solutions to
some IRPM formulations use Transagg
manage both the rock resources and the road network
Forest land.
for large tracts of National
7.
29
SUMMARY
of
CASE STUDIES
Area Planning
Seven area analyses have been completed using IRPM
for approximately
150000 acres of National Forest
land in California Washington Idaho Montana
and
several hundredss of millions of
Oregon representing
dollars in proposed transportation
and
timber
Tests conducted
activities.
in Region
6
and by
the
Intermountain Research
Station indicate that
efficiency can be increased as much as 50 percent
over conventional
manual analysis methods
har-vesting
eco-nomic
1.
used similar formulation
these applications
each
formulation
techniques
was tailored to fit the
local
resource issues.
A variety of resource
and
investment opportunities
were modeled
con-straints
Although
Wildlife.
Deer and elk winter range with cover/
forage relationship constraints indicator species
concerns and migration routes were modeled.
Visual Resources.
Several alternative timber
intensities and road densities were modeled which
reflected meeting visual quality objectives at
different levels and determining
the associated
economic
tradeoff.
Water Quality.
In Umpqua
National Forest a stream
was modeled as a network and threshold values
were introduced
as constraints
on individual
reaches
of
the stream to control delivered sediment.
Timber.
Several alternative timber harvest and
silvicultural intensities and scheduling were
modeled.
Methods.
Alternative
logging methods were
as well
as more
including conventional
exotic methods.
In some cases alternative
logging
methods required alternative entry points into the
network as well as different road
transportation
standard requirements.
Logging
proposed
Transportation
Systems.
Many alternative road
standards road locations and road densities were
considered
in the study areas.
30
While analyzing three areas in Idaho and Montana
researchers from the Intermountain Research
Station
actual
data
on
the
below-cost
sale
issue
produced
that were entered into congressional
testimony
2.
Forest
Planning
Six National
Forests in Region 6 have successfully
linked IRPM to FORPLAN solutions to test their
spatial feasibility and to estimate the effects of
FORPLAN outputs on the Forest road network
projected
over time.
water-shed
Analysis areas outputs of a FORPLAN solution were
to individual watersheds.
Each
disaggregated
was assigned to a centroid
node representing
the
transportation
system entry points for that
watershed.
Along with solving for the best transportation
network for the FORPLAN solution other tests are
made as well
Spatial Feasibility.
Since constraints
on harvest
area openings
commonly referred to as dispersion or
adjacency of harvest openings
are expressed in
FORPLAN as percent openings per decade over very
further
large areas it cannot be known without
whether
the
results
be
can
analysis
implemented on
smaller watersheds.
The only known methods of
making this analysis are either mapping the FORPLAN
solution and inspecting it visually or analyzing an
IRPM solution which considers spatial arrangement.
6 has
One Forest in Region
found that the FORPLAN
constraint
on adjacency
commonly breaks down at the
smaller area level in other words the FORPLAN
solutions are technically
infeasible.
With the
Forests
were
able
to
IRPM however
modify the
FORPLAN constraint
and
rerun the model thereby
of FORPLAN and IRPM
achieving some convergence
solutions.
Full agreement
between the two models
indicates a technically
feasible solution.
Cumulative
Effects.
Some Forests are investigating
cumulative effects
of timber harvest
on watersheds
with IRPM.
FORPLAN solutions are disaggregated
to
watershed
levels to allow the analyst to estimate
and
evaluate cumulative effects associated with
timber harvest and transportation
activities.
Road Management
In Region
6 Deschutes and Umpqua National Forests
tool.
Results are
used IRPM as a road management
and
other
Forests
in
the
Region have
very promising
31
simi-la
transporta-tion
expressed interest in applying the model in a
of ADVENT
manner.
Since IRPM is a descendant
for
and
a
budgeting
program development
system appears to be a promising natural
extension of its use.
Following are two Region 6
examples.
corpora-tions
first example two large development
made separate proposals to expand a major ski
area by building a new ski lodge with increased
The total
parking space and a new feeder road.
the
evaluated
road
was
using
impact on
connecting
The analysis proved that
it would
not be
IRPM.
to expect
the area to operate at full capacity
road to the area would
because the existing access
not provide the capacity without
additional lanes.
One corporation
therefore decided to temporarily
The corporation
drop the expansion plan.
proposing
into the access road was granted
a road to feed
on the condition
that
a mandatory
$300000
at
the
be
made
to
construct
an
deposit
overpass
intersection of the two roads for safety reasons.
The State Highway Commission decided
to construct
some passing lanes on the access highway
as a
solution
to
the
traffic
congestion
problem.
possible
In
the
feas-ible
per-missio
second road management
example IRPM was used
traffic
the
across
Forest based on
predict
timber harvest plans and observed recreation use
levels.
As a result of the
analysis annual
shares
commensurate
programs were developed
and
between cooperating parties were calculated
multiyear capital investment programs have been
The user Forests now are formulating
proposed.
models that will respond to budget funding levels
traffic service
and
address the issue of assigning
levels.
In
to
the
main-tenance
CONCLUSION
applica-tions
The Integrated Resources
Planning Model has proved
trustworthy and reliable in the classical
Now
for Forest planning and area analysis.
is proving
a tool
for managing
existing
systems enabling land managers to respond
quickly and responsibly to changing issues and
current management
concerns.
transporta-tion
EFN
32
it
REFERENCES
RECOMMENDED
READING
G.
Hyde III and M. L.
for Integrating
Meacham.
Analytical Approaches
and
Land Management
Transportation
Planning on
Research
USDA
Forest
Service
Paper
Forest Lands.
INT-361
1986.
1.
Jones
2.
Jones
J.
Four
J.
J.
and
G.
F.
E.
of
C.
G.
Schuster.
An Analysis
of
Below Cost Timber Sales
on
the Appropriateness
Forests.
A report for policy analysis
National
USDA Forest Service Washington
Office Intermountain
In
Economics
of Federal Timber
Research
Station.
Subcommittee
on Forests
Sales Hearing before the
of
the
Committee
on
Family Farms and Energy
99th
House
of
Representatives
Agriculture
Congress First Session Serial No. 99-4 U.S.
Government
Printing Office 1985.
Kirby
M.
Land Use Planning
Transportation
of a
and Integer Programming.
Proceedings
and
Resource
on Systems Analysis
of Georgia Athens GA 1975.
University
Management
3.
Planning
workshop
4.
Kirby M.
P.
Wong
S.
Kirby M.
P.
Wong
Optimization of
of
the Timber
Rural Roads Networks--An
Application
Roads
of
Rural
America USDA
Model.
Transhipment
and
Statistics
Services
Cooperative
Economics
ESCS-74 1979.
Resources
Integrated
Service Management
1980.
6.
Kirby M.
P.
7.
Kirby M.
P.
Model.
Staff
W.
Cox.
Guide to
Hager.
USDA
Forest
Model.
Planning
CA
Sciences Staff Berkeley
and
W.
Guide to
and W. Hager.
USDA Forest Service
Staff Berkeley CA 1981.
Wong
Model.
Transshipment
Sciences
Management
Transagg
Sciences
and
Wong
and W. Hager.
Forest Service
Berkeley CA 1984.
USDA
Guide
to
the
Management
Kirby M. D. Wegner and L. Visser. Advent
USDA Forest Service
Users Guide.
Management
CA.
Sciences Staff Berkeley
8.
Ou
of Integrated
Application
Forest
Planning.
Resource
Planning Model to
City
of
the Ninth World Congress Mexico
Proceedings
9.
F.
and W.
1985.
33
Cox.
II
Ou F.
Cox
and L. Collett.
An
for
Optimization Approach
Transportation
System
of the Twelfth Annual
Analysis.
Proceedings
Conference on Modeling and Simulation University
Pittsburgh Pittsburgh PA 1982.
10.
W.
Below Cost
Schuster E. G. and J. G. Jones.
Timber Sales
Analysis of a Forest Policy Issue.
USDA Forest Service General Technical
Report
INT-183
1985.
11.
34
of
f
Aggregate Design Considerations
RTIP
Team
4
Members
Bill Kolzow
Team Sponsor
6 Regional
Region
Skip Coghlan
Region 9 Regional
Office
Ted Stuart
Team Leader
Region 5 Regional
Office
Carl Davis
Kisatchie National
Bob Pertile Retired
Lobo National Forest
Region 1
INTRODUCTION
Region
Bob
Office
Forest
8
Hinshaw
1
Regional
Region
Office
Road Technology
Program RTIP
Improvement
members surveyed people for cost-effective
they
gathered many
aggregate design technology
basic or widely known ideas which this article
These are not always major items or
presents.
however
they
provide a good
always applicable
checklist
of
ideas and alternatives for the designer.
sometimes apply some of these ideas to
Designers
low-volume roads but forget them while working on
Some of these ideas have
higher standard roads.
been used unofficially
because people believed they
Obviously
were not officially allowed.
or wasteful
techniques
certainly are not
and
desirable but imaginative
approaches
to aggregate
use are not only desired but
encouraged.
While
Team
4
inappro-priate
alterna-tives
follow-ing
With
PURPOSE
the
of
DESIGN
these thoughts RTIP
for design
techniques
Team 4 offers the
consideration.
of whether
to use aggregate
and
of
the
The choices
thickness
required will depend on service needs
failure criteria and potential resource
acceptable
The designer should realistically evaluate
impacts.
these needs.
Aggregate may not be needed for traffic
service level D roads and reduced
aggregate
for an optimum design may be a valid management
decision.
However the designer should clearly
define the results of reduced
aggregate thickness
and
the risk of failure for the manager.
thick-ness
35
The
the
SEASONAL USE
designer must also assess physical
field and the natural variability
conditions
soils.
in
of
condi-tions
traffic off roads during wet periods can
Keeping
result in considerable
A
aggregate savings.
thickness design procedure
for seasonal
haul
soon will be available in the Forest Service
Surfacing Design and Management
System SDMS
Handbook
FSH 7709.56a.
Regions have received draft
copies and the final version is scheduled for
in 1987.
publication
Currently designers must
estimate the seasonal variation of subgrade soil
surfaced roads.
Several
strength for aggregate
studies have been made or are in progress to measure
these seasonal variations.
However the results
have not been fully analyzed and specific design
guides for SDMS have not been developed.
On roads designed for seasonal use the Forest
Service
r
must manage traffic to conform to the design
Timber sale contracts
assumptions.
may specify or
the Forest Service may require seasonal haul
on roads.
Enforcement is a management
responsibility and there are no simple ways to
i
measure or
r verify
field conditions related to road
closures or hauling restrictions.
Again there are
several studies underway
but until these data are
available judgment must be used to make field
decisions.
restric-tion
ALTERNATIVE
SPECIFICATIONS
The designer should write aggregate specifications
for the intended use considering
economically
available materials and local
experience.
Marginal
be
where
aggregates
acceptable
high-quality
may
commonly specified materials are not economically
available.
Forest Service standard specifications
contain
several options on quality gradation and
should take care in
The designer
processing.
the proper specifications
for job conditions
and
all
should examine the specifications
to see that
If
requirements are economically justified.
without
or waived
requirements can be reduced
the designer
should write
sacrificing
performance
special project specifications.
select-ing
specifi-cation
One
is the
example of an alternative specification
index
for
requirement
plasticity
aggregate
In many parts of the country
surfacing.
naturally
materials meeting the PI requirement are
occurring
not
available.
However some rock types display
binder that does not show up in the PI
adequate
PI
36
A way to improve the binding properties with
If PI
specify a finer or denser gradation.
be
tested
delete
it
from
will
required or
for
the
specification.
test.
PI is
to
not
Another
example is the use of degrading
aggregate
with marginally low durability index test results
for surfacing.
If
the
rock is crushed to a coarser
initially it may degrade under traffic
gradation
for some time.
and provide
satisfactory performance
These same rock types may provide natural binder
degradation
through
actually
improving
performance.
to the
source may make
specifications
sources available.
Blending
adequate
scalping certain sizes wasting certain sizes or
if
washing
may make materials in a source acceptable
and
in advance
these options are recognized
provided
for in the specification.
Tailoring
otherwise
SOIL STRENGTH/
SOIL TYPE
CORRELATION
the
A soil strength/soil
type correlation is an aid
available
to the designer of road base and
surfacing.
This type of correlation is developed
by cataloging
and so
all of the
soil strength tests CBR R-Value
on performed on the Forest with the corresponding
This allows the
soil.type or soil classification.
designer to develop alternative designs using a
This would be most
amount of new testing.
Once
during the preliminary stage of design.
and
reduced
the alternatives
have been evaluated
to a few
a verification
strength test could be
for the final
design if investments and risks
The construction
warrant.
engineering personnel
also could use this correlation to evaluate actual
subgrade soils against what was anticipated during
mini-mum
bene-ficial
per-formed
infor-mation
design.
A refinement
on
display
over
AGGREGATE
DECISION TREE
the
this aid would be plotting the
With this graphic
map of the Forest.
the
locator could consider alternatives
better soils.
of
a
The first step in designing an aggregate-surfaced
of whether
road is to make a rational determination
The two basic reasons for
surfacing is necessary.
structural
surfacing are traffic and management
Each reason
and
resource protection.
has a set of factors that the designer should
examine.
con-siderations
Traffic
rutting
include
and management
considerations
traffic
potential of the soil anticipated
37
timber haul
volume and timing of the traffic
activities
timing and amount of administrative
commitment
to road management such as seasonal
closures road surfacing economics road grades
recreation use political pressures availability of
Resource
funds and management direction.
include whether road closures or roadway
surface drainage and erosion protection adequately
mitigate impacts whether roadways will
affect water quality and whether roadway
effects
costs.
outweigh repair and maintenance
or
consider-ations
signifi-cantly
traffic considerations
do not
dictate
surfacing
if resource
or can
impacts are not significant
otherwise be mitigated at lower cost then the road
design should not include aggregate stabilization.
Instead it should use other measures such as
If
either
drainage and dust abatement.
necessitates
stabilization use aggregate
surfacing or other methods such as paving.
If
and
consider-ation
devel-oped
A logic flow chart of some type can assist the
decisionmaker.
Figure 1 is a chart that was
Geotechnical
Engineer on the Plumas
by a
National
Forest and is being used on the Forest.
SURFACING
THICKNESS
VARIATION
the
ROAD
ALONG
SPOT SURFACING
Many designers provide only one or two surfacing
thicknesses for a road usually for the worst
conditions primarily because it is safe and
because
it is inconvenient
and
they believe
for contractors
to vary thickness
However some Forests find that contractors
have no problem changing depths for 20-foot sections
or spreading just a 2- or 3-inch layer.
Typically
worst conditions do not exist over a large portion
of a given project.
Also cut sections or compacted
embankments of competent
materials need less
than transition sections fills of less
materials or low wet areas.
uneco-nomical
fre-quently.
sur-facing
ade-quate
of
planned new construction includes sections
native
soils that do not need
structurally adequate
that do need
aggregate surfacing and soft sections
The extent and boundary of
aggregate surfacing.
these sections may not be reliably located without
an extensive
subsurface
soils investigation.
sections needing surfacing and the amount
needed may be adequate.
The contractor
can then
limits and amount of spot
adjust the actual
during construction.
Some
Esti-mating
sur-facing
38
outweigh
damage
Will
repair/maintenance
quality
water
costs
Yes
data
new
with
QI
to
return
No
No
project
the
for
funds
Are
IYes
Work.
rocking
and
shaping
only
Use
required
as
etc.
paving
dust
support
for
or
on
existing
surface
affect
road
Will
2.
or
route
access
of
method
control
significant
be
1.
Yes
better
a
Minimal
resource
damage
Will
No
No
access
walking
for
alternative
standard
road
Yes
long
too
road
Is
season
YES
available
politicalpressure
or
justify
higher
a
during
road
of
use
require
wet
If
structural
managementdirection
maintenance
plan
road
Yes
Do
there
Is
Stabilization
economics
volume
haul
Do
grades
No
surfacestabilization
adequateresourceprotection
provide
No
to
haul
MMBF
5
road
Are
administrativeactivities
Moisture-Sensitiveoutsloping
road
etc.
closure
limited
R-values
bars
water
Will
Yes
No
No
Yes
with
road
Close
acceptable
significantly
and
soils
Are
50-60
season
dry
the
1.--Rockingcriteria.
ReconstructionTrafficManagementResourceConsiderationsConsiderations
Construction
ROADS
New
rut
soils
Do
be
haul
Can
Figure
struc-EROSION
TRACTION
Some
or
CONTROL
SURFACING
PATHS
WHEEL
native
surfaced roads provided adequate
support but need aggregate for traction or
erosion control on steeper grades.
In these cases
the design may include
1
to 2 inches
of open graded
aggregate for the steeper grades.
tural
Wheel path ruts often develop on old native
surfaced
roads.
Placing aggregate in these wheel path ruts
provides additional traffic support and levels the
road for better driving and drainage while using a
The contractor
minimum amount of aggregate.
material along the road and uses a motor
grader crawler or wheel tractor to spread it into
the
The working
ruts.
equipment and user vehicles
truck-spreads
compact
the
aggregate.
NOT SURFACING
TURNOUTS
traffic and subgrade conditions warrant the
designer can save aggregate on low volume roads by
not
surfacing turnouts or by reducing aggregate
depth on turnouts.
MARGINAL
often exist in areas having
Marginal aggregates
little or no quality aggregate.
Marginal aggregates
do not meet the common
standards of quality
have poor gradation excessive
gate--they
fines
or
poor resistance to traffic or weathering
excessive
deterioration to plastic fines.
However
in some climates
standard specified quality may
Greater depths
represent an excessive
requirement.
of marginal aggregate
resist traffic
may adequately
wear.
Mixing the marginal aggregate with quality
aggregate or other additives also may provide a more
cost-effective
The results of
alternative.
such as in sandstone may still be acceptable.
ASTM Technical
Publication
and FHWA Reports
RD-81-176
and RD-82-056
recommendations
on
provide
a
of
The
using
variety
marginal aggregates.
designer
also should evaluate local
with local
experience
marginal materials.
AGGREGATES
Where
aggre-may
weather-ing
774
STABILIZATION
char-acteristics
dif-feren
Stabilization
can
base or surfacing
improve a marginal aggregate for
or increase
the engineering
of
the subgrade material.
The many
types of stabilization methods and materials
include Portland cement
lime fly ash bitumens
chlorides organic cationic compounds and others.
In many cases
simply mixing a poor material with a
higher quality material such as adding clean sand
stabilization.
to a poor silt can provide
40
The
amount of stabilizing agent depends on
and
each agent has its own strengths
and
limitations.
The many sources of information
available for selection and use of these agents
include manufacturers associations
such as the
Portland Cement Association the Lime Association
and
the Asphalt Institute
textbooks such as Yoder
and Witczaks Principles of Pavement Design
such as AS
professional publications
AASHTO and
TRB Forest Service reports and manufacturers
technical literature.
Some of the publications
contain aids such as charts and graphs for selecting
the
type and approximate
quantities of stabilizing
One
such
aid
is
table
9.1
in the Yoder and
agent.
Witczak
test.
The designer also should not overlook
local
as a source of information.
experience
type
and
many factors
M
SAND
STABILIZATION
WITH TOPSOIL or
PLASTIC CELLS
Sand can be an excellent road-building
material if
stabilized or confined.
Mixing topsoil and organic
duff during construction
or maintenance
helps to
stabilize sand.
Plastic honeycomb
cells filled with
sand also provide a stable surface.
CRUSHED
AGGREGATE
The
Fernow Experimental Forest in West Virginia NE
evaluated
erosion from unsurfaced
roads and
Station
from 1-inch crushed aggregate and 3-inch clean
crushed aggregate surfaced roads.
They found that
erosion from the 3-inch clean aggregate was no worse
than from the 1-inch aggregate sections.
Also they
found that on minimum standard roads the 3-inch
rock one layer deep stabilized the subgrade well.
The rocks worked
into the subgrade during wet periods
until the soil matrix firmly held the rocks and the
rocks adequately
carried the traffic loads through
the
soft material to the more competent
material
below.
The 3-inch rock will not lend itself to
routine grader blading but these roads are not
planned for routine blading.
They might be touched
small
dozer
after
several
a
years of logging
up by
traffic.
The soil-aggregate
matrix is similar to
cobblestone
surfacing.
Preferably the 3-inch.
contain
should
not
fines so that there is
aggregate
room for the subgrade soil to move between
the
This
to
be
an excellent
aggregate particles.
proved
for
otherwise
unsurfaced
spot
surfacing technique
roads and this technique is particularly applicable
for soils that mud up under traffic but that are
from springs below the surface.
not wetted
GEOTEXTILES
surfaced roads over poor
designing aggregate
the
designer should consider the use of
The two
also called filter fabrics.
geotextiles
In
soils
41
separ-atio
uses
materials in surface design are
In
both cases the
subgrade restraint.
of
amount
required
aggregate
surfacing material can
be reduced
with the proper geotextile.
The concept
of separation
is a filter barrier preventing
two
dissimilar materials from mixing the most common
of
use would be to prevent or minimize the movement
weak subgrade soils into aggregate bases or
Geotextiles as subgrade restraint reduce
soil movement
and
soil strain by confinement.
of
these
and
sur-facing.
can assist the designer in
Many publications
and
in surfacing
selecting
specifying geotextiles
manufacturers literature and the
including
Guidelines for Use of Fabrics in
Construction
and
Maintenance
of
Low Volume Roads
No.
USDA
Forest Service and
Report
FHWA-TS-78-205
FHWA June 1977.
com-prehensive
SUMMARY
Members of the Road Technology
Improvement
Program
Team 4 gathered
the
aggregate design considerations
in this article by surveying people for
presented
cost-effective
These
aggregate design technology.
and
considerations
should
techniques
provide a
useful checklist for road surface designers.
EPN
42
Engineering Expert Systems
Fong
L.
Ou
Engineer
Washington
INTRODUCTION
Systems
Office
Analysis
Development
Engineering Staff
intelli-gence
AI
of development
artificial
becoming a promising tool to solve
real-world problems.
AI has been defined as behavior
that would
be called intelligent if
by a machine
performed by a human being and that is used in
robotics expert systems general computing and
After
25
years
is
resolving questions of intelligence and language.
The worldwide
AI market
is predicted
to reach
and $3 billion to $12 billion
$250 million in 1986
in 1990.
From 1986 to 1990 AIs share of the
computer market will increase from 0.2 to 4 percent.
This article discusses the potential of using
expert systems to improve engineering performance.
Expert
Systems
An expert
computer program that performs
at the
level
of
a
human expert in a complex but
field
narrow
or uses human traits like logic to
solve problems.
Expert systems are not black boxes
that mysteriously arrive at conclusions
to problems
to them.
Instead they model the
presented
and
expertise of human experts in a given
domain.
system
is
a
experi-ence
geo-logical
infor-mation
Expert systems have proven useful in diverse areas
such as medical diagnosis chemical analysis
exploration military operation and computer
the problem-solving
To model
system configuration.
expertise of a human expert within a particular
field an expert system requires two types of
or expertise of an
specific knowledge
and heuristic
or
expert including factual knowledge
con-trolling
and general problem-solving
knowledge
strategies such as drawing inferences and
empirical
the
METHODOLOGY
reasoning
process.
methods used for developing
expert systems are
rule-based
technology frame-based technology or a
hybrid of the two.
The
43
I
Rule-Based
Technology
rule-based system gives an organization the
ability to solve only clearly defined stand-alone
the
The basic assumption
is that
skills an
problems.
expert uses to solve a given problem can be extracted
and
effectively
efficiently as rules of thumb and
into an expert system through the
incorporated
process of knowledge
engineering.
Figure 1 shows
of
a rule-based
generic architecture
system and its
three major components
a rule base a blackboard
and an inference engine.
The
A
con-dition
rep-resented
The
rule
the
form
base
of statements each in
a collection
where C represents a
then
and
an action.
Knowledge also can be
as tree-shaped networks
of related
objects
or concepts
known as semantic networks.
In these
facts are clumped together
in
networks
which are interconnected
such
by all possible paths
has-a
as is-a
truck
is
a
vehicle
or
logging
These pathways when
vehicles have wheels.
followed lead to a conclusion or inference
logging truck has wheels.
is
If C
A
nodes
a
a
collection of items that taken
state of the world in which
the expert system operates.
It
can include facts
and
similar
elements.
observations
measurements
The
blackboard
is
describe
together
a
the
The inference engine is the component
designed to
solve any given problem.
It
consists of a control
mechanism and a control strategy.
The control
mechanism uses a predetermined
strategy to search
Blackboard
Rule
Facts
If
C
then
A
Measurements
If
C
then
A
Observations
If
C
then
A
Hypotheses
If
C
then
A
7_1
Inference
Figure
44
Base
Engine
Control
Control
Mechanism
Strategy
1.--Rule-based
system.
solu-tion
mechan-ism
the rule base for
and
the
control strategy
given problem
set
of
constraints
the
control
a
on
imposes
to prevent it from wasting time on stray leads.
through
to
The
blackboard
the
and
a
expert systems
strategies used in rule-based
search
are
called
problems
solving
and backward-chaining.
Forward-chaining
also
called data-driven reason from
systems
initial data or facts contained
in the
rule base and
the blackboard
while
to find a solution
also called goal-directed
systems start
at
a goal
and work backward
to find evidence
to
that
support
goal.
two
forward-chaining
for
backward-chaining
This strategy
Forward-Chaining Control Mechanism.
with
and
looks
a
t
begins
premise
rough the rule
base and the blackboard
to find possible solutions.
The mechanism matches
the
condition
of every
rule against all the elements on the blackboard.
The action
of
the elements
any rule that matches
adds to the blackboard
as a newly inferred fact.
This process continues until the control mechanism
can make no further inference.
C
A
Control Mechanism.
This strategy
Backward-Chaining
with
tentative
solution
begins
a
hypothesis and
looks through the rule base and the blackboard
to
find justifications
for that solution.
control mechanisms match the hypothesis
the action
of every rule the condition
against
of any rule that
matches the hypothesis gets
tested against the blackboard.
Any match of a rule
condition to a blackboard
element serves as
for the hypothesis.
All mismatches point out
other possible hypotheses
which the control
tests in turn.
a
Backward-chaining
A
C
justifi-cation
Frame-Based
Technology
mechan-ism
con-cepts.
infor-mation
A frame-based
system is formed by a set of knowledge
bases and its shape is determined
interaction
by the
of frames and
slots.
Frames are lists of various
concepts features and relationships to other
Slots are more specific pieces of
typically values and procedures that are
included in the frames and further describe the
concepts.
characteris-tics
Figure
2
shows a frame-based
systems knowledge
consists of trainings and
base which
such
location
as
subject
instructor
45
matter
and
objectives
date.
Each
duration
circle
on
the
Training
Semi
na r
objectiveincrease
attendeemanagerial
knowledge
of
spreadsheet
One-Day-Training
duration1
Seminar-Lotus 1-2-3
subject
matterLotus
Training-in-Washington
locationWashington
1-2-3
DC
DC
Seminar-A
date08/15
instructorJohn
Figure 2.--Frame-based system.
paren-theses
represents a frame and each set of
The diagram indicates
represents a slot.
that the concept
Training can be described by a
set of frames including Training
One Day Training
and Training in Washington D.C. and also can be
and
described by both frames of Seminar Lotus-1-2-3
Seminar A.
diagram
Hybrid
Technology
develop-ment
Hybrid systems combine the features and capabilities
The
of
rule- and frame-based technology.
of hybrid systems is limited.
DIFFERENCES FROM
TRADITIONAL
PROGRAMS
Data
Data
In a conventional
Structure.
program the data
to the
pertinent
problem and the control knowledge
exist in the same structure.
The expert system on
the other hand
separates the problems specific
and
the mechanism that
controls the
knowledge
opera-tio
of
Size
the
system.
For the conventional
Base.
computer
size of data base varies.
Expert
base and if-then
systems require a large knowledge
rules to manage the knowledge
base.
of
program
Data
the
46
infer-ences
Completion of Data Base.
Many
handle income ete or uncertain
from the knowledge
base.
expert systems
data by making
can
Most traditional computer programs
Data.
with a numerical data base expert systems can
accommodate
non-numeric qualitative or symbolic
data.
Type
of
deal
Conventional
like FORTRAN
programming uses computer languages
and PASCAL
which were designed for
numerical
manipulating
problems and not well suited
Most expert systems
to expert
system applications.
in the United
States employ LISP for list processing.
LISP operates by linking lists of data and can match
shuttle or take apart lists as needed
concentrate
the
to get
desired information.
the
Recently
software industry has offered software such as
EXSYS that allows users to communicate
with expert
in
normal
or
natural
However
systems
languages.
in Europe
and Japan a language called PROLOG is
favored.
A PROLOG program starts with a logical
statement and tries to determine whether it is true
or false.
Language
com-puter
problem-Problem
Approach
of
Solving
An expert system does not need an explicit
solving algorithm because a separate knowledge
processor determines when where and how to apply
element.
In other words
every individual knowledge
the problem-solving
is
deterministic
for
approach
the
traditional program and heuristic for the expert
system.
con-Presentation
user-interface
Outcome
for their
Expert systems provide an explanation
clusions and offer a reasonably natural
dialogue.
ADVANTAGES
DISADVANTAGES
Listed below are
over traditional
of
computer
consis-tent
problems
1
2
3
of
an expert system
advantages
and
without
the
aid
with
approaches
in
programs
solving engineering
the
The
expert system
decisions.
The expert
answers.
system
provides
reliable
explains or
and
justifies final
formal-izes
The
construction
the
problem
47
of
the
area.
expert
system
4
5
6
7
8
9
10
The
or
expert system serves as an expert colleague
on difficult problems.
expert consultant
The
expert system is more easily
conventional
software.
3
APPLICATIONS
than
symbolic language used by the expert system
facilitates communication
in natural
English.
The
The expert
that would
system preserves expert knowledge
otherwise be lost through retiring
The expert system can train new
key personnel.
personnel in a tutorial context.
The
the expertise of a
expert system can pool
body of human experts to produce
a system that
is more effective
than any one person working
alone.
The
expertise of the expert system generally is
very high-level expertise which is very scarce
and costly in human terms.
expert system makes more expert knowledge
available because the program can be duplicated
and
located in multiple locations and can solve
multiple problems simultaneously.
The
Like other computer software
drawbacks.
The following
are
1
2
expandable
Expert systems
experts.
are
not
as
expert systems have
some disadvantages
creative
as
real
They are not as adaptive as real experts.
At
their current stage of development
expert
systems have difficulty
learning from their
environment
or adapting to new situations the
way humans can.
Expert systems have difficulty
understanding
their own limitations and may attempt problems
that
they are not qualified to solve.
Expert
systems
are still in
and
successful
an
embryonic stage of
of the
applications
system to solve engineering problems are few.
Table
1
shows systems in use or in development.
The
to bridge
following two systems applied
design and
pavement rehabilitation illustrate uses of expert
systems.
development
48
Table
1.--Engineering
expert
systems.
Domain
Expert System
System
Use
in
DIPMETER
Oil
PROSPECTOR
Mineral
HI-RISE
Building
FAX
Failure analysi
SAGE
Structural
analysis
SACON
Structural
analysi
BDES
Structural
design
SPERK
Assessing
damage to
earthquake
buildings
HYDRO
Watershed
management
RI
Computer system
configuration
System
logging
well
exploration
design
s
s
Development
in
noise
behavior
CHINA
Highway
design
DIRECTOR
Urban transportation
education
TRALI
Traffic
SCEPTRE
Pavement
signal
setting
rehabilitation
this list were obtained from
Research
the
Transportation
The
Board Washington D.C. January 13-16 1986.
list is not inclusive.
Source
the
Annual
The data
Meeting
49
on
of
4
encom-BDESfor
Bridge Design Expert System
which
passes the ideas of AI with the bridge design
and M.
process was developed
Biswas.
by J. G. Welch
BDES currently considers only superstructures of
short- to medium-span bridges.
BDES can design
structural steel and prestressed
concrete
girders.
3
and
4
show
Figures
a bridge
geometry and its
girder cross-section selected by BDES for a design
problem.
Bridge Design
2
Application
SCEPTRE
BDES
The
1
Application
SCEPTRE
Surface Condition Expert for Pavement
Rehabilitation which was developed
by S. G. Ritchie
C-I Yeh J. P. Mahoney
and N.
Jackson.
It
evaluates
pavement surface distress and recommends feasible
rehabilitation strategies for detailed analysis and
SCEPTRE was developed
based on a pavement
design.
rehabilitation process that evaluates pavement
surface conditions
analyzes and evaluates
adequacy
develops alternative strategies and
selects an optional strategy.
for
Pavement
Rehabilitation
Plan
is
the
struc-.tural
Figure 5 shows a solution that SCEPTRE selected as a
rehabilitation and maintenance
strategy for a given
road segment to deal with alligator or fatigue
The four recommended
cracking in the wheelpaths.
strategies which have varied life expectancies are
to do nothing
to fog
seal and to add a thin asphalt
concrete
overlay and a medium asphalt concrete
over-lay.
Cross-Section
End
Span Dimensions
4-Span Bridge
View
Span
Mid
f-325.00
Span
Top
Flange
1
x
eb
1WL
16
x
PL
.
I
113
Top
u
Flange
GIRDER
x
11
PL
DESIGN
60-0
x
WEB
COMPACT
111
16X
16
41
Deg
a3
PL
1Web
16
.0
feet
1
SPAN
11
Bottom
Flange PL
64
-SIMPLE
PLATE
1-459--95
60-0
Bottom
Flange PL
x
x
i.
by
BDES.
girder
cross-section
r-125jT65
325.00
1s
16T
I
Interstate
Figure 3.--A
ýI
feet
selected
Figure 4.--A
by
50
BDES.
bridge
feet-.j
22.5
Highway
geometry
/
selected
se
YOUR MINIMUM DESIRED
6
YEARS.
IN
THE
OUTPUT BELOW
FOR EACH
RAM WILL BE
THE
LIST
FOLLOWS
OF
FEASIBLE
SERVICE
RAM
IS
P
AT
THE
LEAST
LIFE
PROBABILITY
THIS LONG.
STRATEGIES
HOW
an
5.--Feasible
TO START
EXPERT SYSTEM
pavement
THIS
FOR
DO-NOTHING
FOG SEAL
THIN ASPHALT CONCRETE
OVERLAY
ASPHALT CONCRETE
OVERLAY
MEDIUM
Figure
FOR
rehabilitation
7%
P
25%
50%
84%
P
and
SECTION
THAT
THE
PAVEMENT
P
P
THIS
maintenance
IS
ACTUAL
SECTION
EXPECTED
EXPECTED
EXPECTED
EXPECTED
strategies
SERVICE
IS
LIFE
AS
LIFE
3
LIFE
4
LIFE
LIFE
6
determined
9
by
YEARS
YEARS
YEARS
YEARS
SCEPTRE.
tool to assist
Expert systems can be an effective
Engineers in solving engineering problems.
However
only when they are
expert systems can be effective
Therefore
applied to the proper problem domain.
the Engineer
should evaluate the feasibility of an
expert system for a particular problem domain before
and using the system.
The evaluation
developing
should determine the need of the organization define
problem/situation identify the resources need
the
value such as the productivity
increase and select the proper tools.
the
determine
expert systems tend to be large complex
difficult
to build.
Yet commercially
available software tools or shells have existed
for several years and can make the expert system
The number of these
more manageable.
development
tools is growing table 2 lists different shells
available and their supporting hardware.
During the
next few years more shells will become available
and
shells will become more powerful and useful for
down
operational systems and shell price will come
and
increase.
as market pressures
competition
comparing the features of the expert system
shells currently in the market can help Engineers
select an appropriate
one to support the expert
effort.
system development
Current
costly
and
How-ever
51
Tool
not
Data
Corp.
available
Unix
68000
market.
the
on
Reasoning
Data
not
available
MVS
under
Silogic
SYSTEM
Knowledge
not
Data
Inc.
Group
Carnegie
Craft
Knowledge
available
compatibles
compatibles
and
IBM
mainframe
and
IBM-PC
Knowledge
supermicrocomputersFRAME-BASED
and
IBM-PC
IBM
System
Expert
Motorola
Texas
Plus
IBM-PC
Instruments
Texas
Personal
Instruments
compatibles
Technowledge
IBM-PC
Personal
Inference
Unix-basedmachines.
Technowledge
IBM-PC-ATDECVAX-11/780
and
and
LISP-
various
Inc.
EXSYS
EXSYS
Development
Mechanism
mainframe
Development
MVS
under
IBM
Inc.
M-1
Consultant
Instruments
compatibles
and
IBM-PC
IBM
Control
S-1
Consultant
Transform
mainframePersonalConsultant
IBM
Corp.
Logic
Texas
Plus
System
Expert
Workbench
VAX-11/78
Artelligence
Processors
Unix
and
PC
IBM
Inc.
AMS
Environment/MVSBackward-Chaining
Expertelligence
Inc.
Computer
Macintosh
Apple
Corp.
Equipment
Digital
OPS5
Environment/MVS
OPS5
OPS5
SYSTEM
HYBRID
EngineeringEnvironmentIntellicorp
Mechanism
Control
Forward-Chaining
HardwareRULE-BASED
Developer
SYSTEM
Exper
Not
available
expert
2.--Shells
systems.
developing
for
Shell
N
Automated
Table
Ln
SUMMARY
appli-cation
per-formance.
This
article has
an overview
of
the
presented
expert systems to improve engineering
Two engineering
expert systems developed
the
and
State Highway
by
Virginia
Washington
illustrated
Departments
expert system application.
of
com-puter
to
Although
expert systems offer opportunities
increase productivity and reduce costs they cannot
solve all engineering problems.
As with other
the
should
Engineers
perform a
programs
before
feasibility study
initiating expert system
development.
REFERENCES
U.S.
Department
Information Service.
1.
Database
86.
2.
NTIS
of
Commerce
Citations
National
Technical
from the INSPEC
Expert Computer Systems
1986.
PB86-858244.
Ritchie
G.
S.
C-I
Yeh
Feb.
85
Mahoney
J.
P.
to
Expert
-
Jan.
and
Jackson.
of an Expert System for
Development
Pavement Rehabilitation
Paper
Decision-Making.
the
65th
Annual
of
Meeting
at
presented
Research
Board Washington D.C.
Transportation
N.
January
3.
1986.
Waterman
R.
D.
A Guide
1986.
Addison-Wesley
Welch
Systems.
J.
G.
and M.
Biswas.
of
Application
in
the
of
Bridges.
Paper
Systems
Design
Expert
the 65th Annual Meeting of
at
presented
Research
Board Washington D.C.
Transportation
1986.
January
4.
f4
EfN
53
Haul Speeds Controlled
Grade Surface Type or Horizontal
Road Width for Forest
Alignment
Identifying
by
Development Roads
Max E. Evans
Transportation
Region 3
SYNOPSIS
Planner
Travel time and
Service is based
Byrne Nelson
BNG published
haul
costs used by the Forest
on the Logging Road Handbook
by
referred
to as
and
Googins hereafter
in
1960.
Service
the
USDA
Forest
by
on a
the speed of a truck operating
thus
states that
Road is controlled
Forest Development
mainly by the
the
horizontal
alignment
grade and surface type or
states that
FSH 7709.56.4.32
and number of lanes.
by grades
speeds for loaded trucks are governed
haul
and
greater than 8 percent for favorable
for
adverse
hauls.
3 percent
It
current method used in Region 3 toýdetermine
Our
travel times does not reflect this principle.
been
that
to assume
any improvement in
practice has
horizontal
surface type width or
alignment would
The
time
and
thus
haul
costs.
decrease travel
of
when
volume
break-even point occurs
an adequate
road
reduced
haul
cost
timber hauled over the
at
a
offsets the costs of improvements.
Although
costs
can reduce truck operating
a road surface
benefits
from
reduced
road maintenance
and
costs
haul
times are not as great.
The
improv-ing
accu-rate.
differ-ences
Identifying which road characteristics when altered
will affect travel times makes our method more
Since this may result in less economic
between alternatives in a transportation
analysis must display
analysis the transportation
costs of concerns mitigated by each economically
land managers
ID teams and
efficient alternative.
selections
on the
must base recommendations and
the
various
costs and benefits of mitigating
alternatives.
concerns in economically effective
DISCUSSION
BNG were collected
from March to
1948 during the winter of 1958-59 in the
in the eastern
United States and in 1952
this
States.
Most agree that
publication
Data
for
55
August
western
United
is
the
most up-to-date study on operating
logging trucks.
BNG indicates that travel speeds when controlled by
the grade of the road and
the
surface type are
increased by less than 5 percent when a native
surface is improved to an aggregate surface or an
aggregate surface is improved to an asphalt surface.
BNG attributes this reduction
in travel time to the
change in the rolling resistance between the various
Therefore if the horizontal
type surfaces.
and
road width control the speed
improvements
have minimal effect on
to the road surface will
travel times.
decreasing
align-ment
The current method of analyzing
truck speeds and
3
the
latest edition of
costs in Region
is based on
the Manual Network
Analysis Method for
of Resources
hereafter called Manual Network
Ronald
Analysis
Tangemen
Clyde Weller and Bill
y
Woodward published in October
1982
this
also is the basis for Region 3 MINCOST tables
Table
Haul
at FCCC.
Classes on page 36 of the
Manual Network Analysis divides roads into 320 haul
classes related to t e number of lanes road surface
horizontal alignment and grade of the road.
Table
2
in the Manual Network
Analysis gives the travel
times in minutes per mile for each class of road
described in Table 1.
Table 2a in the Manual Network
Analysis gives the speeds of a loaded and empty
truck hauling on a road described in Table 1.
Tables 2 and 2a of the Manual Network Analysis were
for a
truck
developed
using BNG corrected
55 mph
for the
having 400 horsepower
speed limit
and for a
value of 0.85.
Transporta-tion
publica-tion
1
B
The
Network
Analysis originally was published
transportation
planners to compare
relative transportation
costs associated with road
improvements could
improvements in determining which
be economical.
However the Manual Network Analysis
now has been incorporated
into Region 3s timber
Amendment
33 to FSH 2409.22.
procedure
by
appraisal
Region 5 also is modifying Tables
2 and 2a in
the Manual Network
Analysis to be included in their
appraisal process.
Considering this added importance
given the Manual Network Analysis travel times
derived from its use must be accurate.
as
Manual
an
aid
to
1
ANALYSIS
The
travel speed for a truck traveling on the forest
by design features
development
system is controlled
of the
of roads that
limit the physical capabilities
comfort
truck and affect the drivers psychological
56
align-ment.
Consider the case of a truck that can do
road with an excellent
a double-lane
mph
this truck is operated
on a 12-foot-wide
without
ditch
with
the
same grades
road
a
single-lane
and alignment as the first road the driver will
driver will
As a result the
feel less comfortable.
level.
45
on
If
operate the truck at a lesser speed than if the only
truck.
of the
limits were the physical capabilities
from
the
results
in operating
This difference
speeds
on
situations
effects
of
the
different
psychological
the
drivers comfort level rather than on physical
changes
in
the
road.
primarily controls
Determining which characteristic
truck
is
when considering
the
of
a
important
speed
Charts I and 2 in
the
economics
of improving a road.
the Manual Network
Analysis indicate trucks operating
on a single-lane graded and drained road with a
4
to
poor alignment and an adverse haul of from
7 percent
will require a travel time of 10.00 minutes
that
These charts also indicate
per mile min/mi.
reduce
an aggregate
surface placed on this road would
of
a reduction
the
travel time to 7.01 min/mi
If
2.99 min/mi
or 30 percent.
we assume the grade
on this
controls the speed of the truck operating
time
in
the
travel
as
stated
FSH
7709.56
road
less
or
less
than
5
should be reduced
by
percent
These charts also
than I min/mi based on BNG.
that if the alignment were changed from poor to
fair the travel time would be reduced
to 7.47 min/mi.
of
if
the
be true only
This would
alignment and width
indi-cate
the truck speed.
If the grade
road controlled
in
the
first
controls the speed as
assumption the
be
reduced
from
travel time should not
improved road
the
alignment.
in BNG as a
travel time are contained
Data regarding
in
of
of
The
first
series
graphs
series
graphs.
in
time
3
8
in
BNG
relate
travel
through
Figures
various
for
roads
with
mile
to
the
minutes per
grade
value
values.
The
types of surfaces and a
of
the
of
the
is the
relationship
horsepower
B
B
truck
to
the
gross
vehicle
weight
hp
GVW.
series of graphs in Figures 10 through
13 in BNG relate the travel time in minutes per
number of curves
the
mile to various radius curves
Road widths
the
width
of
the
road.
per mile and
lane
and
a half
single lane with
are double lane
and
lane
without
ditch.
ditch
single
The
second
57
Figure 16 in BNG relates the percent increase in
travel time for an empty truck traveling on a
lane-and-a-half or single-lane road because of
conflicts with oncoming
traffic that relate to the
turnout spacing and the traffic volume on the road
in vehicles per hour.
This
analysis considers a standard truck having a
375-hp engine hauling
4800 board feet per trip.
The GVW of the standard truck considered
in the
analysis was 86000 pounds loaded and 30000 empty.
The truck is assumed to operate at an elevation of
The
factor for this
6000 feet above sea level.
combination
of features is 2.66 for the
loaded truck
and 7.63 for the empty truck.
B
Analyzing the first series of charts in BNG for the
standard truck operating
on an aggregate-surfaced
double-lane
road resulted in the chart shown in
The speeds are those a
figure 1 of this article.
loaded and empty truck can sustain on a road with no
consideration
to alignment.
given
375
50
0
r
Horsepower Truck
f..
Aggregate
40
I
N
N
10.0
0.
0
.
Vý
20
.
$4
S.
30
Surface
ZIP
.ýIa
000
_1
1.
000
t
oa
10
12
4
8
Adverse
-4
0
Haul
-8
Favorable
-12
Haul
GRADE
Figure
1.--Speed
in
miles per hour
58
versus
percent
grade.
-16
Table 1 of this article shows the speeds resulting
from analyzing the second series of charts in BNG
for the standard truck operating
on roads with the
various horizontal alignments and widths as defined
in the Manual Network
Analysis.
Superimposing the speeds shown in table I on the
graph in figure 1 results in a series of graphs
the maximum speed a truck can maintain
as
showing
restricted by grade and surface type and/or the
Figure 2 shows
alignment and number of lanes.
road with
the resulting graph for a double-lane
truck is
fair alignment.
The maximum speed of the
restricted by the horizontal alignment to 34.5 mph
and
for an empty truck for grades of between
-5 percent
and
to 31.9 mph for a loaded truck for
and -4 percent.
grades of between
hori-zontal
4
2
Table
1.--Maximum speeds
controlled
by
alignment and
Load
on
K
Alignment
Excellent
Factor
167
Truck
63
30
Primitive
13
8
Half
Si ngl a
a
Lane
With Ditch
Si ngl e
Lane
Without
Ditch
39.0
40.8
39.9
38.2
39.7
39.0
40.0
42.3
41.4
33.3
40.8
36.7
31.6
30.2
34.1
32.0
31.9
34.5
24.3
28.3
33.1
25.8
29.3
27.4
21.1
24.7
22.7
20.3
23.3
21.7
19.3
Empty
Average
26.8
29.7
28.2
Loaded
16.7
14.0
13.6
Empty
Average
20.0
18.2
17.1
16.7
Loaded
Loaded
Empty
Average
Poor
and
41.7
42.9
42.3
Empty
Average
Fair
Lane
Double
Lane
47.2
47.2
47.2
Loaded
Empty
Average
Good
width.
Loaded
15.0
17.6
16.2
59
34.1
32.8
26.1
15.4
23.0
25.2
24.0
22.7
20.9
15.0
375
Horsepower Truck
Surface
Aggregate
z4
50
top
0
0
40
Double
Alignment
.
20
V
-6
31.9
.z
Fair
0
34.5.
30
Lane
33.1
ý
ý
i
.
Jet
wft
10
\O
8
12
Adverse
4
0
Haul
-4
-8
-12
Favorable
-16
Haul
GRADE
Figure 2.--Speed
double-lane road
miles per hour versus percent
grade
without a ditch and a fair alignment.
in
on
a
Figure 3 shows that for a single-lane gravel-surfaced
road with a fair alignment maximum truck speed is
restricted to 25.2 mph for an empty truck for grades
of between
and -9 percent and to 23 mph for a
loaded truck for grades of between
and -7 percent.
7
3
from this series of graphs were
Speeds determined
then adjusted to surface type where the speeds are
The speed
controlled
by the
grade and surface type.
of the empty truck operating
on a single-lane
or
lane-and-a-half road were then reduced
10
by
percent
to account
for conflicting
traffic of 12 vehicles
per hour with turnouts spaced at 1000-foot
Figure 4 shows the results as speeds in miles
hour
and figure 5 shows travel times in minutes
per
per mile.
inter-vals.
Several judgments affect the selection of factors to
determine speeds and travel times for figures 4 and
5.
The first was where to break the charts for grade
and
surface type.
The class for primitive road
60
375
Horsepower Truck
Surface
Aggregate
50
L
0
E
W
Alignment
30
10
Without Ditch
Fair
.
40
20
Lane
Single
e--40976t.
r
ý
25.2
eýaoQ
23.0
%
24.0
.
NQ-12
8
4
Adverse
0
Haul
-4
-8
Favorable
-12
-16
Haul
GRADE
in miles per hour versus
Figure 3.--Speed
single-lane road with fair alignment.
percent
grade
on
a
surface has been deleted for the single-lane road
because there is no road surface less than a native
In a timber sale
surface road.
appraisal allow
cost
to
an
adequate
running surface
adequate
provide
on the road for economical truck operations.
Figure 1 indicates that the speed of a truck
road
aggregate-surface
operating on a double-lane
varies from 50 mph at 0-percent grade to 40 mph at
2-percent grade to 23 mph at 4-percent grade.
This change is a speed reduction of 20 percent
between
0- and 2-percent
grades and of 50 percent
Therefore
between 0- and 4-percent grades.
into
to 0 percent
dividing the grade range of
and
to 0 appears
to
grade ranges of
4
2
4
2
appropriate.
CONCLUSION
that
The analysis to identify road characteristics
times
control speeds resulted in different travel
Many of
from those in the Manual Network Analsis.
76
are
but there
the
travel times are identical
increased
classes
The number of haul
ones.
dif-ferent
61
10-Exceiient
Grade
No.
Lanes
Type
Surface
Alignment
Adverse
10-7
12.32
8.73
6.51
4-2
2-0
0-4
4.04
4.04
4.32
2.78
2.93
3.59
2.93
3.59
4.18
6.51
4.61
4.07
4.07
4.31
7.29
6.53
6.84
4.29
4.29
4.57
4.86
6.53
7-4
Good
Paved
Fair
Poor
Primitive
12.32
8.73
9.00
Excellent
12.32
8.73
Good
Aggregate
Native
Paved
Fair
Poor
Primitive
12.32
8.73
9.00
6.84
7.62
Excellent
Good
Fair
Poor
Primitive
12.32
8.73
7.32
12.32
8.73
9.00
7.32
8.00
Excellent
Good
Fair
Poor
Primitive
12.86
9.00
6.79
Aggregate
Native
Paved
c
m _
-jo
-
Aggregate
in
12.86
9.00
9.75
6.79
6.89
8.04
Excellent
Good
Fair
Poor
12.86
9.00
7.12
Primitive
12.86
9.00
9.75
7.12
7.22
8.37
Excellent
Good
Fair
Poor
Primitive
12.86
9.00
7.50
12.86
9.00
9.75
Excellent
Good
Fair
Poor
Primitive
12.86
9.00
12.86
9.00
10.00
Excellent
Good
Fair
Poor
Primitive
12.86
9.00
Excellent
Good
12.86
Native
Fair
Poor
Primitive
ALIGNMENT
Excellent
Good
Fair
Poor
Primitive
9.00
50
20
K
110.00
12.86
ý
K
100
K
K
K
100
9.00
9.00
K
K
10.00
12.86
N
4.--Round
minutes/mile.
trip
2.86
2.61
4.18
2.93
3.59
4.07
4.18
4.07
4.59
4.59
4.87
5.16
6.53
2.90
3.05
3.59
4.07
3.04
4.23
4.43
4.92
5.47
3.64
4.62
7-10
4.18
2.61
3.01
3.59
Haul
5.16
-
6.75
5.16
4.31
2.61
4.18
2.93
3.59
4.07
4.31
6.53
6.75
5.16
6.75
5.16
6.53
6.75
5.16
6.75
5.16
6.53
6.75
5.36
7.08
4.18
2.97
3.64
4.38
4.38
4.62
1
5.36
5.47
7.75
4.48
3.12
2.97
4.38
4.68
5.16
5.47
3.64
4.62
3.64
4.38
4.62
5.36
5.36
5.47
7.08
7.75
7.08
7.08
7.75
7.75
7.50
7.61
5.77
8.75
7.75
6.79
6.79
6.89
7.14
8.29
4.28
3.25
3.25
4.54
5.22
6.02
3.94
3.94
7.12
7.12
7.22
7.47
8.62
4.52
4.79
5.47
6.02
8.29
7.50
7.50
5.09
3.33
3.94
7.61
5.47
5.22
7.86
9.00
6.02
8.29
1
3.16
3.64
4.62
2.97
4.78
4.98
5.47
3.29
3.94
5.22
4.82
3.64
3.25
3.94
4.38
4.38
5.36
4.62
5.36
4.38
4.38
3.25
3.94
5.77
7.08
7.75
5.36
7.08
5.36
5.22
6.02
4.38
4.38
5.22
5.36
5.36
5.47
6.02
5.36
5.36
4.38
4.38
5.22
7.08
5.47
6.02
7.08
8.29
7.08
7.08
8.29
7.08
7.08
8.29
Where
R
Average
N
Number
radius of
of
curves
curvature
per mile
between
between
nodes.
nodes.
50
NOTE
20
10
I.
10
2.
3.
Figure
Favorable
4-7
Haul
10
travel
time
on
haul.
Grade use the favorable
Speeds between the lines are controlled
Speeds outside the lines are controlled
For 0
highway
logging
62
trucks
by
by
by
ALIGNMENT.
GRADE.
roads physical
characteristics
10-Excellent
Grade
No.
Lanes
Type
Surface
Alignment
Adverse
10
7/16
Good
Fair
Poor
Primitive
Paved
Excellent
4-2
14/27
10/22
14/27
23/35
23/30
7/16
10/20
14/20
17/20
7/16
10/22
13/27
10/22
21/42
21/42
21/35
21/30
Fair
Poor
Native
Primitive
7/16
10/20
13/27
13/20
Excellent
Good
Fair
Poor
Primitive
7/16
10/22
12/27
Excellent
19/42
10
Aggregate
12/27
19/30
7/16
12/20
17/20
7/14
10/20
14/24
23/37
23/33
23/26
21/23
14/24
21/26
17/20
16/20
38/47
38/42
32/35
29/30
45/47
40/42
32/35
29/30
26/32
21/26
16/20
26/32
26/30
21/26
45/47
40/42
32/35
29/30
40/39
33/33
26/26
17/20
16/20
26/32
21/26
16/20
26/32
26/30
21/26
17/20
16/20
16/18
42/39
26/29
21/24
33/33
26/29
26/26
21/24
21/23
7/14
10/20
13/24
21/37
38/39
42/39
26/29
21/24
33/33
26/26
33/33
13/24
21/33
21/26
26/29
26/26
21/24
10/20
10/16
7/14
7/14
o
N U
Aggregate
10/20
12/24
10/20
21/23
19/37
42/39
33/33
33/33
26/26
21/23
26/29
26/29
21/24
7/14
10/16
Excellent
Good
Fair
Poor
7/14
10/20
14/24
23/36
38/36
38/36
26/29
21/24
14/24
23/31
30/31
30/31
26/29
21/24
21/23
Primitive
Excellent
Good
Fair
Excellent
Good
Fair
Poor
Primitive
ALIGNMENT
K
K
100
23/23
14/21
19/21
7/14
10/15
14/15
7/14
10/20
13/24
21/36
37/36
38/36
13/24
21/31
30/31
30/31
23/23
21/23
13/21
19/21
7/14
10/15
13/15
14/15
7/14
10/20
12/24
19/36
12
19/31
7/14
10/15
_
K
20
20
K
10
23/23
16
16/18
24
21/23
16/18
15/16
16/18
16/18
24
19/23
19/21
12/15
14/15
36/36
30/31
23/23
38/36
30/31
Number
16/18
24
21/23
26/29
26/29
23/23
16/18
21/24
21/24
21/23
16/18
19/21
16/18
14/15
11
Where
N
21
14/15
12/21
Average
21/24
19/21
12/23
R
26/29
26/29
23/23
radius of
of
curves
between
curvature
per mile
between
nodes.
nodes.
NOTE
I.
2.
3.
by
R
N
50
10
1
16/18
14/15
13/23
10/20
21
19/21
10/20
100
50
K
14/23
10/20
K
K
26/26
16
16/18
15
37/39
12/24 J-1-9733
19/26
19/23
12/23
12/16
15/16
Poor
Primitive
Native
21/23
15/16
13/16
16/18
15
15/16
13/23
16/20
26/32
Excellent
Good
Fair
Poor
Primitive
Paved
Figure 5.--Speeds
26/30
10/16
Fair
Poor
Primitive
Primitive
29/30
7/14
Native
Excellent
Good
Fair
Poor
29/30
Primitive
Good
g
26/32
14/23
14/16
10/20
Excellent
m
45/47
40/42
32/35
32/35
29/30
19/35
10/22
10/20
Fair
Poor
21/26
-
40/47
40/42
32/35
37/47
37/42
19/42
Haul
7-10
4-7
17/20
Good
Paved
0-4
2-0
23/42
23/42
10/22
Good
Aggregate
Favorable
Haul
7-4
10-7
roads physical
For 0
Grade use the favorable
haul.
are controlled
Speeds between the lines
Speeds outside the lines are controlled
characteristics
63
by
by
ALIGNMENT.
GRADE.
on-highway-logging-trucks
miles/hour.
align-ment
from 320
of
less
for the
is
Determining the horizontal
roads with grades of greater than 4 percent
critical since the travel time is the same
to
405.
excellent good fair and poor alignment
except on single-lane roads.
Determining the grade
for single-lane
roads with fair poor and primitive
alignment also is less critical since the travel
times generally are the same for the various
for all grades of between
and -7 percent.
align-ments
7
Figures 4 and 5 show the travel times and speeds for
various haul classes by the physical characteristics
this should make the tables easier to use.
The haul
classes to use with MINCOST at FCCC can be coded
with 4-digit numbers as follows
1
2
3
4
The
1
3
first digit represents the number
double lane 2
lane
and a half
a
ditch.
single lane without
The
second
1
paved
The
third digit
1
and
digit
excellent
5
represents
aggregate
2
represents
2
primitive.
good
3
3
the
and
lanes
surface type
native.
the
and
of
alignment
fair
4
poor
digit represents the grade
0 percent
to
percent to 0 percent 2
-4 percent 3
percent to
percent
4
-4 percent to -7 percent 5
percent
to
-7 percent
to -10 percent
percent 6
7
less than
percent to 10 percent 8
710 percent and
9
greater than 10 percent.
The
1
fourth
2
4
2
7
7
4
an example
a
single-lane road without a ditch
and with an aggregate surface fair alignment and
and
grade of between
percent will be haul
class 3233.
As
4
2
a
Develop-ment
Remember that
these tables apply to Forest
Roads FDRs.
Generally alignment controls
the maximum speed on low-standard
roads.
However on
a
few FDRs speeds in excess of 55 mph can be
for long
distances.
This situation is similar
to that of the
Federal Aid System Roads where the
55-mph speed limit is the limiting factor for
distances.
Travel times on State and
county roads and on FDRs where the alignment and
grades allow sustained high speeds should be
from observations
of the
legal speed limits.
sus-tained
con-siderable
deter-mine
64
i
I
Facilities Maintenance
Management
George J. Lippert
Chief Facilities Engineer
Office
Washington
Imple-mentation
This
fall
marks
the
formal
start of
a
Service-wide
to improve facilities maintenance.
maintenance
of a structural
management
one
of
the
two
recommendations
was
provided
process
team that reviewed
by an inter-Region/Station
emphasis
building maintenance
practices
Service-wide.
Manage-ment
The first recommendation structured maintenance
management
improvements will be implemented using
and
an Engineering
videotape
presentation
series publication.
The former will
provide an overview of maintenance
management
and
elements.
This is for use at Supervisor/
Ranger meetings workshops and other meetings to
and
ensure a broad understanding
support for
management
improvements.
a
princi-pals
EM
main-tenance
The
EM publication
provide further detailed
examples of existing
This publication
maintenance
management
systems.
in
with videotape
be
distributed
conjunction
may
presentations.
will
information guidance
and
The structured facilities maintenance
management
framework is included
in the draft revision of
This handbook will be reissued to
FSH 7309.11.
Directive
Interim
February 19 1986
replace
This also is slated for distribution
FSH 7309.11.
this fall.
1
main-tenance
The
second
recommendation
dealt with improving
This training aimed at improving
training.
You
inspection skills is in the formative stages.
will be hearing more about this in the next few
months.
EFN
65
Ups
The Series
Engineering Technical
Information System
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Engineering
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roREST
SRVCf
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1NENi0FAGICU
Volume 18
September-October 1986
Engineering
Field
Notes