ENGINEERING
TECHNICAL
FIELD
INFORMATION
SYSTEM
DATA
Volume
i
Field
I
Number
5
TECHNICAL
NOTES
RETRIEVAL
REPORTS
CURRENT
TEXTS
AWARENESS
Notes
0 October 1973
Dip Design
New
E n g n ee
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FIELD NOTES
DIP DESIGN
Civil
- Designs
Engineer
By
H.
D.
Completion
of
November 1971
the
in
article
this article
answer
will
was sparked by the question
Field Notes. It
the questions
4
Region
Investigations
Comments
Authors
Ryser
Hafterson
Standards and Technical
posed and
is
raised by Royal M.
hoped that publication
will
catalyze
of
this
of design
note-book
needed for rational dip
information
Field
measurements
limited
be conveniently
can
forms of the type
size
number of
copies
shown
from
acquisition
design.
and
recorded
Figure
in
7.
on field
processed
Interested readers
may
obtain
a
the author.
INTRODUCTION
Draining
water from the surface of unpaved
accumulates
sufficient
designers of mountain
arrogant
that
This paper
A
theoretical
and to provide
more
rational
roads.
discouraging.
section
Often when
a dip design technique
traffic
a
dip
is
destroys
watershed
is
the riding surface
a familiar problem
doing a good hydraulic job
treatment
a basis
is
presented
for making
design technique
It
is
hoped
and share
of opinion
is
which simultaneously
satisfies
or
to
becomes
it
driving over
so
it.
these conflicting
requirements.
the design on arbitrarily
measurements
the adjacent
it
bounces the vehicle hard enough to rap the head of anyone
it
presents
hydraulic and
to damage
energy
roads before
is
selected
a thorough understanding
to develop
the field measurements
and has yielded
that this article will encourage
their
which are badly needed
to be used. So far the technique
constants
to the somewhat
I
results
readers to
findings through the forum
needed due
of the problem
has been used
if
by
this
basing
which are not too
make
of FIELD
subjective nature
the needed
NOTES.
A
wide cross
of the measurements.
out-sloping
The problem on unpaved
do because
roads
is
to remove water from the road surface.
on muddy roads creates
traffic
the road surface
has been used
on the rutting tendency of the road
when wet
has resulted in disfavor
such
structures
as
Dips in the road profile
dont
characteristics
Dips
very long.
the wet road
necessarily
mud
when
ruts
reduced by the
These
provide
by being too abrupt
driveability
of success
degrees
on
Outsloping
road users
soils
who have
depending primarily
which become slippery
slipped off the road. Various
open top culverts do an excellent job when conditions
and high maintenance
siltation
with varying
among
first
are
are
right but
but unfortunately good
hydraulic
common.
an obvious
coincide
solution
good
with
and are often too shallow
constructed
mud
formed by
ridges
ridges in the bottom
of the
sacrifice
water for
divert
as traffic
Effectiveness
dip.
out of the rut
squeezing
of the dip act
to effectively
from the road easily but
water
divert
Most dip designs
driveability.
formed which cut through the top
are
mud
costs
to
difficult
is
which the water follows. Insloping or
ruts
surface.
This
as
wheels
is
pass
uses
further
through.
free-board
the ruts.
A
3-inch-deep
6-inch-deep
Gravel
dip.
requires expensive
as
The
rut with 3-inch-high ridges
surfacing through
is
periods. Recalling
new
that
in
the bottom
enough to cause
the head
criteria
bumping that
are
needed
if
water from leaving
failure
of
a
the answer to rutting
failure
by
caused
typical
but often
reduction
of
of the dip.
so that the rutting action
sediment storage space to
sufficient
is
dikes to prevent
may be
to build the dip with enough freeboard
through and so that there
obvious
the dip
is
maintenance and does not prevent
sediment accumulates
solution
as lateral
occurs even
last
between
on some of the shallow
cant
cut
maintenance
dips makes
it
dips are to be further deepened.
DESIGN RELATIONSHIPS
Head bumping results from
by the
large
Speed plays an important part
dip.
and some
accelerations
cautiously
unacceptably
through the
by a design speed
so
it
in
determining
designers apparently
dips.
expect
Other geometric
the
elements
seems that consistency
imposed on the vehicle
accelerations
vertical
the magnitude
driver to slow
of the
vertical
down and proceed
of the road are coordinated in part
would be fostered
if
dips also
conformed to
these criteria.
The
basis
for design from the
relationship
of speed
standpoint
to vertical
of
traffic
driveability
This relationship
acceleration.
is
developed from the
can
be approximated
from
the dynamics of centrifugal acceleration
z
R
a
2
1
where
centrifugal
v
tangential velocity
R
If
acceleration
a
up to
tipped
is
along the upper an. lower
accelerations
therefore
with
approximated
relationship
sufficient
developed
In
K
Solving
expresses the curvature
L
length
A
algebraic difference
of vertical
1
equations
and
of
for
K
spite
vertical
arcs
and the radius
can
be
curves are circular
Ref 4.
curve
in
2
parabolic arc in units of feet
a
per
%
3
A
in ft
grades in
%
2
R
Solving
circular
100K
K
where
-e.
is
R
where
rather than
become
of this the radius of curvature
by assuming that the
accuracy
accelerations
centrifugal
segments of thv
curves are parabolas
the curve.
throughout
changes
plane then the
a vertical
In highway design the vertical
The
f.p.s.2
f.p.s.
radius in ft
the circle
vertical
in
in
and expressing
speed
V
ý2
l
a
in
00K
miles/hr
yields
4
depen-dent
K
Equation
4 shows
upon speed
acceleration
Design
is
V
not
that
K
also
V-2
46.5a
measures the
and the acceptable
precisely defined
will
be discussed
a.
The
later in
curve being
acceptable
vertical
the section
entitled
Criteria.
As mentioned earlier hydraulic effectiveness
control
acceleration
vertical
and
of a vertical
driveability
of rutting.
This depth
or freeboard
demands depth for sediment storage and for
is
important dimensions.
3
defined
in
the Figure
1
along with other
Q
G
GA -
GD -
Freeboard
-
Distance
L
-
Length of
if
-
from center of dip
vertical
approach
grades are not
Length of approach
this
paper distances
relationships
imperative that the
with which he
is
convenient
is
will
and
lengths
sag
will
be different
equal
- Dip
1.
Dimensions.
be expressed
in
and grades
feet
using absolute
values
Ig
the calculations to the crest
designer relate
bottom
to hydraulic
grade
developed
are
PRC
curves crest
Figure
The
and sag
Adverse dip grade
Lo
percents.
dip
the
crest
not necessary
F
Throughout
within
changes
grades symmetry between
Approach
but
T
often
Original road grade
I
will
be expressed
of the grades so
or the
sag curve
it
as
is
situation
dealing.
multi-plied
The
F
freeboard
the top
can
be found by noting
of the crest. Then
the point
Then
the difference
PRC
of reverse curvature
by the distance
for equal
Ks on
Lo between
the
that the grade
crest
is
in
KA
and grade
0
at
the bottom
of the sag and
the low point
grade
between
at
of the sag and
PRC
and
F
Ref 4.
and sag curves
F
From L
at
elevation between
equal to the average
them
0
the freeboard
is
GD Lo
100
the high and low points on the vertical
Lo
K GD
4
curves
5
then
K
FGD2
100
or
6
100F
GD
K
relation-ships
6
from equation
Notice
characteristics
driveability
that the adverse
-
GD
dip grade
F and
freeboard
of both hydraulic
a function
is
L
curvature
vertical
and
Other
respectively.
are
LAK IGDI
7
K
IGAI
8
TLIGDIIGI
2
IGAI
IGI
-
DESIGN CRITERIA
drive-ability
The
preceding
have developed
paragraphs
the necessary design relationships basedon
param-eters
at
various
the dip vertical
vertical
in
and on hydraulic
speeds
curves can
now
and freeboard
acceleration
effectiveness
be obtained
However
requirements.
and grinding out a family of design values
constraints imposed by vehicle
for erosion
control.
Also
for diverting
through knowledge
it
before
allowable
speed
plugging
maximum
mentioned earlier an acceptable
as
values for
Design
these
would be helpful to investigate the
and by the
underclearance
water.
of vehicle
vertical
dip spacing
allowable
acceleration
is
not
Hand-book
yet defined.
Vehicle
Underclearance
2
Ref
jounce.
the
limits
front and rear overhangs
and
for various
at
maximum sharpness
vehicle
dynamic conditions
Both composite long vehicle
have been compiled to illustrate
cars.
They are therefore
with
the possible exception
center
the
worst
considered
equivalent
K
The minimum
crest
vertical
K
The
in
is
Traffic
likely
by
allowable
Engineering
and
are
full
given which
using Forest
roads
cars.
given by Baerwald are converted
K values
are
shown
in
5
to
entitled
Table
to be. about 0.9 since the. full jounce condition
extremely improbable.
of
to appear on future
vehicle
passenger
clearances
the technique outlined in the section
minimum
for dip design appears
curve
the
for the typical
the dimensions
2 by
Figure
resulting
in
front dive rear jounce
possible dimensions
conservative
as
Field Measurements.
as
of camper trailers pulled
limiting design values
shown
tabulated
such
and composite short vehicle dimensions
In order to obtain
radii
are
of curvature. Minimum
1.
on a
TABLE
1.
- Maximum
Vehicle
Vertical
Sharpness
Dynamic
K
Condition
Longest Front
Sag
as Limited by
Underclearance.
Vehicle
Curve
of Curvature
Normal
.2
Front .Div
.4
.2
.3
.4
Rear Jounce
Full
Rear
Joce
Normal
-
Front Dive
.4
Rear Jounck
.8
.6
.1
.2
Full Jounce
Shortest
Front
Normal
Front Dive
.1
.2
Rear Jounce
Full Jounce
Rear
.3
.2
.8
.6
.4
.7
.7
Normal
Front Dive
Rear Jounce
Full Jounce
Crest
Normal
Longest
Front Dive
Rear Jounce
Full Jounce
1.85
.1
.1
.1
.2
Normal
Shortest
Front Dive
Rear Jounce
Full Jounce
oW
QW
ý.Q
.4.
FRONT
WHEELBASE
2.
Vehicle
REAR
.
OVERHANG
OVERHANG
Figure
.......4..
Underclearance
6
Limits Curve Sharpness.
Erosion
impor-tant
Control
be spaced
a variety of
Ref
considerations
closer intervals
at
soil
6. These
parameters
Their criteria
as
lead to the generalization that dips must be deep and must
road grades
and road grades
types
influencing
criteria
the Northern Region
in
have been developed for
by Packer and Christensen
from a study of 720 sites indicate that the most
developed
criteria
Spacing
increase.
road surface erosion
for cross drain spacing
is
soil
are
type
to limit 83 percent
Ref 5.
and road grade. Packer
of erosion
to depths
rills
less
than
spac-ings
1
inch. In addition to the
for the road position
the slope.
in
Figure
A plot
3.
soil
type and road grade they include
on the slope the exposure
direction
of their spacing requirements
Since
the plot ignores
their
for various
modifying factors
modifying factors to account
of the slopes
soil
all
types
and the steepness of
and road grades
is
shown
of which call for closer
cate-gories
the plot gives
their
account for the adverse
Therefore
the
maximum allowable
dip grade
curves are plotted
are defined
in
Table
shown
in
spacing.
Figure
by adding
L
4.
to their
The
Their
plotted
data has been modified to
data represents
erosion
the distance
The
distance.
soil
2T.
type
2.
200
150
NI
----/00
i-T
---------
50
4
Figure
rT1TI4
8
APPROACH GRADE
3.
-
4A
lo-cated
- Dip Spacing
For V20
as Defined by
m.p.h.
Road Grade and
F1.0
Soil Type.
a5fp.s.2 and
road
on upper third of north facing 80 percent
7
slope.
GA
G
Figure
TABLE
2.
-
Erosion
Group
o
U
oo
- Dip
Spacing.
Potential of Soil Groups
Description
Ref
Hard sediments shale
II
Basalt
III
Granite sandstone gneiss schist
soft
quartzite
Andesite
V
Loess
8
soft
slate limestone rhyolite
conglomerate
shale
IV
6.
of Parent Material
I
a
A
4.
limestone
glacial
silt
Superimposed on the plot are
from
driveability
were not
in and are derived
built
merely steepening
of tangency
dashed
The
their
coincide
T
line
spacing
L.
is
showing road grades
lines
considerations. These lines show
at
common
shown by
GA. The
grade
4 shows the dimensions
2T
S
L and
limit
spacing required
when
reached
shown on
is
needed for the
the dips
if
more closely by
be spaced
is
limit
indicate
grades achieved
that the dips can
fact
approach
the sustained
of reverse curvature. This
a point
Figure
from the
G which
the points
the graph
the
as
derivation.
9
since
_LGDG
G
8
LKGDGA
7
T
GA
2
-
and
then
K
S
Substituting
in
values for 20 m.p.h.
For instance
a sustained
and connected
10
-
foot freeboard and vertical
of 6 percent
grade
by a 10.5 percent
research to verify an acceptable
vertical
rill
1.0
GD G
GA G
of
acceleration
5
f.p.s.2
the values plotted.
gives
feet
GD GA
acceleration
depth
is
subject
erosion
type
in soil
grade. This
standard
brings out
to question. Ideally
the tolerable
impairment watershed damage and maintenance
above
criteria
are.
The door
the
125
maximum
allowable
basic assumption of a 1-inch
erosion
traffic
may be the best there
The
at
of additional
the importance
and to determine
safety of operation.
consistent with
requires dips to be spaced
III
criteria
should
Practically
costs.
be related to
however
the
open....
is
mini-mized
out-sloping
Design
water
of the Hydraulic Bottom of the dip requires additional study. In order to remove
from the road the hydraulic
road at 90 degrees then
and
hand
if
creation of a soft
a dip crossing
when
at
a
longer
skew
grades are low.
the comfort of passenger
bottom
or
outsloping
must slope to one
insloping
is
spot and the ensuing
will
acquire
From
chuckhole
some grade
truck
considerably
dips used to date.
The
is
is
to be avoided.
automatically
but
may
to be
On
also
the other
require
but tends to twist the frame of
occupants
trucks so that they favor square dips. This twisting
the typically abrupt
the dip crosses the
standpoint skewing a dip greatly increases
a driveability
car and pickup
side. If
required if sedimentation
dips designed
effect
by the
longer and the twisting problem may not be as
9
has been troublesome on
criteria
severe.
in this
paper
will
be
Acceleration
Vertical
is
AASHO
mentioned by
briefly
given as the upper limit for a comfortable
through
ride
Policy
Ref
1.
a sag vertical
A value
curve.
of
f.p.s.2
1
However
is
for
trade-off
both sag and
crest
curves other
value is therefore
to the vertical
seldom
acceleration
value of acceleration
is
be
as
such
criteria
attained.
Since
minimizing
as
the length
the length
designing
allowable
The example
design
The problem
6 percent
on
shown
in
Figure
illustrated
and
is
sacrificed
National
through
the practical
at
20 m.p.h. with a
---
-
40
5.
A
effectiveness.
for
trial basis
Forests. Results are
a workable value.
5 f.p.s.2
Figure
operation.
was selected on a
Manti-LaSal
5 will illustrate
39ýA
this
inversely related
to gain hydraulic
aspects of the foregoing
requires the design of a dip with 1.5 ft
road which can be driven
is
of the dip requires that the allowable
of 5 f.p.s.2
the Uinta
far but indicate that this
so
theory.
acceleration
vertical
dips into timber roads
very sketchy
of the drainage dip
high as possible consistent with safe vehicle
required wherein comfort but not safety is
A maximum
govern and
headlight sight distance
- Example
10
Design.
vertical
freeboard
for a
acceleration
of
It
is
desired to build
station
is
selected
undisturbed
angle dip with the hydraulic
a right
because
it
is
bottom
at
station
473.
and the water will therefore
section
a daylight
This
flow
onto
ground.
K
V2
10 F_
GD ýK
K GD
Lo
PT
The approach
grade
473
PRS
will
be
1001.5
1.72
1.72
9.35
selected
arbitrarily
4
9.35%
6
use
8 percent
as
5
16.1 ft
489.1
16.1
/%
1.72 ft
460525
46.5a
489
thereby
making
the grade
change
A
GD
GA
AK
L
If
the
erosion
percent
selected
distance
approach
grade
from Figure
GA- G
of
is
2115
also
8.0
2
230
29.8 use 30
9.35
30
feet
17.35%
8.00
17.35 1.72
TL GDG
2
9.35
is
6.0
-
satisfactory
satisfactory.
8
115 ft
6.0
The approach
7
ft
then
grade
the arbitrarily
GA could
also
selected
3 if the soil type were known.
PC489-30459
PI
Elevations
can be calculated
as
follows
474
but
are
normally scaled from the
Station
Elevations
15PI
473
PRC
-6% 16
489
-9.35%
474
PC
459
3916.7
I
I
8% 15
11
3915.74
i
I
3914.34
3915.54
8
have been
profile.
Elevations
of several
points on the curve
reference. In practice
sufficient
accuracy
1
K
TABLE
are calculated
A
_
L
by
from the
scaling
profile.
3
17.35
_
0.578%/ft
30
- Example
3.
Table 3 below for future
in
normally obtained
is
Curve
Vertical
Calculations.
Chord Gradient
Station
Elevation
1-8.0%
459
PC
3915.54
1
1/2.578102.89%I
-5.11%10
469
I
.5781
479
5.78%
.5781
489
PT
-0.51
3915.03
3915.10
16.44%10
5.78%
2.89%
1/2.57810
0.07
10.67%10
0.64
3915.74
I
19.36%
of the
These are the calculations for the sag portion
the crest
portions
much
curve.
vertical
symmetrical
usual
though not mandatory
about the PRC.
miles per hour
Fifteen
simpler.
The
V2
K
Similar calculations are
dip.
The
is
152
46.5a
46.5
practice
is
5
tabulated
make
to
data given in Table
minimum
the
-
__
tabulated
speed
made
the
for
two
4 makes the design
since
4
0.97
Instruc-tions
if
the
maximum acceptable
0.9 was
shown
for use
earlier
vertical
When
minimum
to be the
of the table are
as
is
assumed to be
allowable
due to vehicle
acceleration
drainage
PRC
G
and
exit
GA
is
2 percent
grades are different
enter the table using the desired
GD
to connect the otherwise
for each curve
a distance
at
VPIs
point. Locate the
Note that the tabulated
entrance
A value
of
K
underclearance.
follows
G. Establish the middle of the dip
If
f.p.s.2
dips on a uniform grade enter the table with the uniform grade
designing
desired
5
using
GD
from the
greater than G.
GA
or if
approach
independently
is
grade
laid
and can be found by interpolation
12
Lo downgrade
and L. Lay out the taper T.
not
GA
2 percent
greater than
and use the adverse
out curves. Length L
for each approach
is
grade
different
grade
GA.
TABLE
Speed
4.
- Dip
5
Values for a
f.
p.
S.
2
Freeboard
Grade
G
Design
GA
15
0.5
1.0
LIT
GD7.2
Lo 7
L
GD
Lo
1.5
T
L
10.2
GD
Lo
10
T
12.4
12
2
4
11
25
14
42
16
58
4
6
13
36
16
55
18
73
6
8
15
48
18
71
20
91
8
10
17
63
20
89
22
111
10
12
19
80
22
108
24
133
12
14
20
98
23
130
26
156
14
16
22
119
25
153
28
182
GD5.4
20
Lo
9
GD
Lo
GD9.3
7.6
13
Lo
2
4
16
30
20
48
4
6
20
46
23
6
8
23
66
8
10
26
10
12
12
14
25
16
23
65
68
26
88
27
92
30
114
89
30
118
33
144
30
115
34
149
37
178
33
145
37
182
40
214
GD4.3
GD6.1
Lo
Lo
12
GD7.5
16
Lo
55
20
2
4
22
35
27
4
73
6
28
58
32
82
36
104
6
8
33
85
38
115
42
140
31
8
10
38
118
43
153
47
182
10
12
44
157
49
196
52
229
12
14
49
201
54
244
58
281
30
GD3.6
GD5.1
GD6.2
Lo
Lo
Lo
14
20
24
2
4
29
41
35
62
40
81
4
6
37
70
43
97
47
121
6
8
45
108
51
140
55
168
8
10
53
153
58
191
63
223
10
12
60
205
66
249
71
286
13
quan-tities.
The
are equally suited for hand or computer
procedures
Automatic
computer
earthwork
balanced
Dip Location
is
before
locations
When
dipping
a dip
undisturbed
is
or
alinement
is
be
factors.
of steep grades and at locations where
top
with horizontal
should
earthwork
preferably
The purpose of the dip is to divert
do an unacceptable
amount of damage. Therefore
can
it
are at the
minimum. Correlation
as
Therefore
the profile
in
the
since
earthwork
an important design function.
the road surface
such
the dips are introduced
be made by hand using unit mass
should
adjustments
effective
before
of earthwork
not be used however
disturb the necessary relationships of the dip.
will
essentially
computations
adjustment programs should
the
fill
from
water
the most
height
is
needed to avoid hazardous situations
the middle of a sharp curve.
to be constructed
material
in
since traffic
an existing road the
will
crest
soon displace the loose
fill
be
should
curve
built
from
material.
FIELD MEASUREMENTS
As previously mentioned
maximum safe
of the
this
value and also
Allowable
various
adapts the technique
will
be influenced
range
it
is
skew and
driver
as
above.
technique
for estimating
inspection.
Future
type
of vehicle
experience.
important to develop
for disseminating
a
limit
loaded
weight
issues
Because of the subjective nature
of these FIELD
obtained
which
suspension
a wide
a composite viewpoint representing
experience
at
for safe operation.
value requires a highly subjective judgment
acceleration
of the factors mentioned
an excellent forum
develops
upon knowledge
predicated
be determined by driving through a dip
can
by a variety of factors such
of the measurements
is
which seems to be the upper
the speed
road alinement dip
stiffness
section
to construction
accelerations
and recording
Determining this acceptable
to dip design
acceleration. This
maximum vertical
speeds
rational approach
this
vertical
by
NOTES
engineers
should
provide
Service-wide.
para-graphs.
The
equivalent
Once
radius
K
the vehicle
is
determined by
speed
profiling
and dip curvature
calculated.
14
K
the dip as outlined
are
known
in
the following
the acceleration
is
easily
The
derivation
following
once
means of calculating the
leads to a simple
the elevations of three equally spaced
points
on
y
px2
the curve
vertical
acceleration
and the vehicle
speed
have
con-stant
been determined.
form
In general
of
the equation
parabola
a
expresses the sharpness of curvature
of change of grade
rate
vertical
is
spaced
at
x
K
thus determined if the vertical
sharpness of curvature
distance
h
as
is
at
shown
the point
Y
in
Figure
Yi
px2
6.
V2
4a
46.5
curve
sharpness
K and
velocity
6.
-
Ya
Sharpness
of Curvature.
the general parabola
qx
YL
r is
evaluated
Y -h
YR
Y
ph2
Yo
Yi
Combining these equations
2p
Ref 4. This
are known.
found by measuring the elevations of three points equally
Figure
origin
Y
is
Y
Taking the
Meyer
derivative
K
L
I
The
The second
Al
determined from Equation 4
acceleration
r.
is
a
Acceleration
qx
of change of grade
or rate
2p
The
is
h
ph2
at
all
-
qh
- 2Yi
YR
15
r
r
qh
gives
YL
three points
2ph2
r
Finally
solve for 2p and multiply by 100 to express 2p in units of percent
2p
This
can be used
equation
lh0
YL
-
YR
2Yi
form by plugging
in this
in
per foot.
11
K
the elevations
or
rod readings of the
three points.
To
and that 20 m.p.h.
constructed
it
several
assume that the dip previously designed
the procedure
illustrate
times.
the following
The
next
step
rod readings
is
is
judged to be the
to profile
3.16
2.65
the dip.
maximum safe
in
Table 3
speed
Three points spaced
is
by driving through
10 feet
apart have
2.72.
Then
10
1
K
100
3.16-22.652.72
0.58
1
la
and
I
a
The
K
V2
0.58
46.5
202
mathematical agreement implies a precision which
conditions
since the
constructed
4a
5.0
46.5
will
not be obtainable
dips will not be perfect parabolas
as in this
under
field
contrived
example.
Several refinements
rod readings are plotted with an exaggerated
shown
in
Figure
an accurate
Averaging
will
field irregularities
7.
profile
two
Equally
and then
spaced
scale
or three sets as
give better accuracy
suspension
are
shown
in
the following
from actual measurements.
example taken
The
needed to cope with
and do not
measurements
equally spaced
shown
because
significantly
will
vertical
and smoothed
are not necessary
yield improved accuracy.
the overall
16
- the
by eye
object
is
rod readings from the smoothed
minor undulations
affect
scale
are absorbed
vehicle
The smoothing
by
motion.
to
as
obtain
curve.
process
the wheels and
It
is
important to note that the value determined by
experienced
the vehicle
suspension to
downward
accelerations
the necessity
technique
this
is
not the true
by the occupants of the vehicle due to the damping
acceleration
are experienced
of treating the
skew and
of the dip
effects
Implicit in the foregoing
sequentially.
in
by
provided
that both upward
to the fact
and sag portions separately
crest
vertical
and
description
the measurements
is
and
Never-theless
factor
critical
the experience
Perhaps
calculations.
of change of acceleration
the rate
is
of the technique
Substantial modification
paper will hopefully provide
this
measurement
gained through
rather than
will
indicate that the
the acceleration
presented
here would undoubtedly
a rational
basis
itself.
result.
for further investigations of dip
design.
DIPICALCULATION
SHEET
ROAD
-DIP
O O
LOCATION
3
o-ACCEPT
. DY.
ý
-44/1
ýýCr1P
77
I-..._
O
_
1
O
I
VEHICLE
f
QS
j
PATE
BLE
ROAD
SPFD._-UP
DOWN
._17b$ýi
C ND/TIONI4__ALINMENT
tt1
y
RAM
D_
ROAD
GRADE____I
ROAD
X
iM4x
N
11L dp
Fr-
IC1y
MdH
BOTTOM
1
1.
2
SKEW
a
-fu
ooy
a
4PS
FALLS
LL--
L
C
OI
--Q
_LO.ý
OJI
0.
W
I.
O
ý
j
hC
V__
I
I
O QI
Figure
For Construction
Equation
11
yýv
ti
t
DESCRIPTION
_QP
n.
ýý
FUNCTION
c
RFMARKý.
%ý
O
ýý
O $
r
51ýeýD
I
HYvaA
O
U
-/
SLOPE
_ HYDRAULIC
7N _9109ý
S
WIDTH
IIi
ROAD
SOIL
F
9
Inspection
7.
it
-Field Measurement
is
merely necessary to
against the value used in the design.
17
and
Calculation.
profile
the dip and
checkK from
oIý
REFERENCES
1
AASHO. A
of State Highway
2.
Baerwald John E. Editor.
Haupt Harold
U.S.D.A.
4.
Meyer
D.C.
Officials Washington
Engineers Washington
3.
of Rural Highways. American Association
Policy for Geometric Design
A Method
F.
Intermountain
Carl F. Route
Engineering
Traffic
D.C.
1965.
Handbook.
of Traffic
Institute
1965.
for Controlling
and Range
Forest
Experiment
International
3rd Ed.
Surveying.
Sediment from Logging Roads.
Ogden Utah
Station
1959.
Co. Scranton Pa.
Textbook
1962.
5.
Packer
Paul E. Criteria for Designing
Sediment.
6.
Packer
Lester
Drainage
8.
Logging Roads.
Ogden Utah
Station
Pence
Science Vol.
13
and Locating
No.
1
Paul E. and George F. Christensen.
Secondary
7.
Forest
Salvadori
M.
Dip.
Jr.
Field
U.S.D.A.
Inc.
1967.
Guides
for Controlling
Intermountain
Sediment from
and Range
Forest
Experiment
1964.
A Method
Notes
Vol.
Mario G. and Melvin
Prentice-Hall
Logging Roads to Control
March
Englewood
L.
for Determining the Construction
3
No.
Baron.
3.
Forest
Service
Numerical Methods
Cliffs N.J.
18
U.S.D.A.
1961.
in
Grade
in
1971.
Engineering.
a
Road
NEW ENGINEERING ORIENTATION
PROGRAM
By
The new
in
Forest
Richard
Service Orientation
The new
January 1973.
comprehension. These
orientation
slide-tape
Office
Program for Engineers was sent to the Regional
program
programs are
will
in living
indicate the students
color short from
and interesting to both new and regular Forest
informative
the earlier engineering
program replaces
orientation
level
11-15
by
a
of
minutes.
Service employees.
system developed
Offices
accompanied
presentation
a slide-tape
is
mini-exam.The Mini-Exam
booklet
self-evaluation
G. Deleissegues
Engineer Washington
Civil
This
1969.
in
super-visors.
The 1969 programmedlearning system had many strong points such as
It was accepted
by management and well-received by both trainees
It
was
It
provided
effective
in
reducing
and
attrition
effective
as
an operating
and
and
live
program.
and denoted
It
trainees with large
engineering
specific
developed a professional
and showed the trainee
Forest
as
interest
of orientation
are utilized
and background
by the Forest
and knowledge
material
Service.
of available
a representative of the engineering
context some deficiencies
SS were
The
It
later as
Some of
noted.
failure
career alternatives
profession on the
use of too
and
for the trainees.
much programmedinstruction
up-to-date audiovisual
above
material which
could
not be used
with
their
techniques.
the program has been reanalyzed
the shortcomings
the need to revise
and to include
material due to its volume.
tool.
to the deficiencies noted
of communicating
were
at home
the first-line supervisor.
The
lacked
1969 programmed-learning subsystem
these deficiencies
material was not well-designed
changed to strengthen
employee
the
to complete SS-l and SS-2
did not involve
a reference
pinpointed
in
The
It
Due
his role
amounts
which
Service teams.
In the same
series
skills
supervisors.
and to
give
new
Past feedback
engineering
from
the first part of the system
an interface and communication
his supervisor.
19
between
field
the at
the two
and the format
employees the
evaluations
home
people
feeling
of the program
or office
involved
portion
- the
new
The revised version of old SS-1 -2 and
SS-5. These are available
through
-3
now
is
Regional
I
SS-1 through
Revised
1
ý
Phase
called
and
of SS-1 through
consists
Offices for your immediate use.
eliminating
the
programmedlearning which was
by
not applicable in this situation and
1
by
SS-5 are characterized
brief easy and informal
style
which
a
using
is
enhanced
en-The
by the use of a colorful character
Old
Old Timer
All Forest
in
-
personnel
well worth
they
reviewing.
employee we
to take the time to see
you
organization
program.
You may
are sure to learn something they
it.
concept
current
want to present
didnt know
this
about
of the following
consists
TT
10
7000
Supervisors
TT
11
7000
Part
TT
12
7000
Part II
TT
13
7000
Part III
-
TT
14
7000
Part
IV
-
TT
15
7000
Part
V Impact
TT
16
7000
Self-Evaluation
TT
17
7000
Orientation Booklet
list
I
Guide
The
-
The
-
Greatest
Great
Men
Tradition
our Mountains
the Action
Is
-
and a glossary of often-used
Orientation Booklet.
Good
to Match
Where
Sufficient
Mini-Exam
new
includes
an introduction
abbreviations
Self-Evaluation
quantities
Offices for distribution to
-
words
TT 16
trainee will need only booklets
Regional
you
the orientation
is
are a seasoned
Service.
The new system
The
orientation
Service employees will benefit from the history
program to all Forest
the Forest
if
courage
programs and challenges described
O.T.
Timer.
The new
Even
called
employees.
20
reading
Mini-Exam and TT 17
of these two training booklets
The
suggested
and acronyms.
remaining
booklets
were sent to
are kept
with
the slide-tape
programs.
the program
Additional
is
The
binder
copies of
all
training booklets
through Central Supply Washington
Previous
WO
A
orientation
Central Supply
limited supply
until
subsystems
- the
new
TT
is
returned
to the Regional
mission
Appropriation
10 through
TT 17
are no longer
All other subsystems are
the five
slide-tape
the
Old Timer
the Forest
still
in
the
new
tell
you
all
through the
system texts
Office.
is
them.
available
SS-l contains
the
Service and a Program and
for use.
available
Engineering
hearing your comments both good and
any ideas you have for improving
its a subject
programs
in
available
programs have replaced
training texts for the slide-tape
and organization of engineering
you have seen
we would appreciate
After
numbers
Office.
of the old programmedlearning orientation
Section.
Offices.
for this program are available in limited
July 1974 from the Division of Engineering Washington
history
Let
it
when
stay with the program set slides and tapes
should
and when
sent to Forests
bad on
Orientation
the package
System
including
it.
about the Forest Service
about which we should
be well informed.
21
-
its interesting informative
and
REGIONAL
OF ENGINEERING NEWS
DIVISION
5
Region
Wins Award
Slide-Tape
I
The
Forest
I
Planning
Services
Transportation
Project located
Berkeley
in
Engi-neering
R-5
and assigned to the Division of
.ýýý
has received
ý
F
National
Ann
produced
ETr
show
Film
Educational
Award
Corneille
slide
Festival
for a recently
presentation.
The
is entitled
1973
the
The
What-if
and was developed
Analysis
for
manage-711
Oakexplaining transportation
to Forest
tools
ment and
The
positions.
won
presentation
Slide-Tape
tF
staff
Trophy
in
the
land in April.
200 film and
It
Best of
the Film
Festival which was held
Y
r
analysis
Officers in
in
was one of over
slide
entries
entered
internationally.
develop-the
The
Leader of the Transportation
plan-slide
V.
M.
Dekalb
Planning
Project
Project
Ann
Corneille Past President
of
Project
Oakland Board of Education and sponsor
of
the film strip award and James Halverson
of the
Lawrence Berkeley
Laboratory who produced
tape show receive the award.
meat
the
is
Berkeley
Stanford
the Project in the
The
R-5
What-if
developed
University
in
ning and managing
cooperation
Analysis
show
is
Forest
available
for use in
road systems on
Forests. These techniques
from network
with the University
and San Jose State University.
field and widespread
computerized
techniques
analysis
ranging
are being
completing the
of various
National
data collection
System Planning
Transporation
analysis
to
of California
Implementation has begun on
Service use should
occur
within
a few years.
upon request from the Division of Engineering
RO.
Editors Note
4 6 8
9
and
We
will
month preceding
happy
be
10 Please
to publish
news items from
submit your news item to reach
the next
months
publication.
22
the
all
Regions.
Whats
Washington Office
the
news in Regions
on the
first
1 2 3
day of the
WASHINGTON OFFICE DIVISION OF ENGINEERING NEWS
AND STANDARDS
CONSULTATION
C. R. Weller
shore-line
fish-ing
North-ern
gen-erated
Assistant Director
Chippewa
Chippewa
Flowage.
Flowage
and land. Ninety-two percent
National
in
significance due to
the world.
States Power
tribe
owns
of near-pristine
expanse
wild atmosphere and reputation
acres within
Company owns approximately 25000
acres
of the dam with
This
the first project
is
Because of the resource values
of the project lands
as
the best muskellunge
the project
LacCourte
the focal point
recommended
the U.
by
is
for recapture
Government
the Federal
is
now
by the Forest
is
before
the
in
Service.
1968 recommended
and that the lands be integrated
Chequamegon National Forest. In March 1972
recommended recapture and return of Indian lands to
the remainder to be a part of the National
Indian
of a major natural resource
into the contiguous
Interior also
boundary
Oreilles
Forest. All power
Department of Agriculture
S.
area has
undeveloped.
from the dam. The project
releases
Power Commission for relicensing and
water
The
is
approximately 1800 acres and 110 acres are National
controversy.
recapture
a 17000-acre
There are approximately 27000
downstream
Federal
its
is
of the 205 miles of shoreline
U.
S.
Department of the
the LacCourte tribe
-
oppo-nents
Conservation
environmental
groups have alleged that present management
values.
Petitions to intervene
to the relicensing.
public involvement
Hearings
Forest.
Several State agencies
appears
D.C.
have
filed
also
threatens
the ecological and
by both supporters
and
been involved. On-the-ground
to favor recapture.
on the relicensing have already
started in Washington
have been
September
been held
13.
23
in
Sawyer County Wisconsin they
TECHNOLOGICAL IMPROVEMENTS
Heyward
Taylor
T.
Assistant Director
Name Products
Evaluation
of Trade
evaluation
of highway trade
name
Engineers
by memorandum dated
categories
were evaluated.
Used
Highway
in
Construction
products
24
1973.
An
or Maintenance.
has been distributed to
1000
all
Materials
Regional
different products
in
23
depart-ments.
Subcommittee
The
along with
in
was made
available
AASHO
the
or rejection
which the products
1.
2.
to the
a brief
Materials.
7.
8.
Bituminous materials
12.
Testing
various
concrete
13.
materials
trade
Structural
categories
systems
components
14.
Structural
concrete
admixtures
15.
Bituminous
membranes
paints
rejuvenators
and preservatives
and materials
16.
Concrete
finishing
Reflective crack
control
17.
Soil stabilizers
products
18.
Traffic marking materials
Concrete patching
19.
Mulch
materials
20.
Miscellaneous
21.
Rust passivators
22.
Joint fillers seals and
and roadside
Culverts and drainage
name
in
materials and
cement
Deicing
by name
with respect
and construction
Portland
and erosion
controls.
materials
23.
Adhesives
chemicals
Materials Engineers
be consulted
The
listed
equipment
cement
structures
Regional
status
of the evaluation.
explanation
structures
10.
is
and use
Skid control
Barriers
9.
product
11.
Waterproofing
6.
Each
membership and
its
Aggregates
curing
5.
State highway
various
a description
AASHO
are
were evaluated
Portland
4.
by
Service through
Forest
and additives
3.
was compiled by the
supplied
name and address
and
Nearly
of products
Subcommittee on
the manufacturers
to acceptance
80-page
list
on Materials from information
list
participation
The
August
products
are in the best position
with
respect
for further information
to
their
in this area.
24
use
to decide
in
on
a forest
the usefulness
environment.
of the
They
should
OPERATIONS
func-tions
Harold
Strickland
L.
Assistant Director
The Washington
Management.
Engineering
of Engineering and the Deputy
the Director
The Sections
on matters
principal functions
dealing with Forest
The
Programs.
section
Aiken
are handling
working
Management
Systems.
with Congress
and Pollution
Trails
Messrs. Frank
Mrs. Aileene
titles
Forest
mail and liaison
Congressional
Roads and
Development
Frost Management Engineers
and Mrs.
Chiefs Office for National
Section
and Management
for Engineering Operations
staffed with four people
is
Management
Office Engineering
to the Assistant Director
support
as staff
Abatement
Hammond
and Dale
O.
McVay Management Assistant
appropri-ation
Phyllis
coordinate
NFS
all
material concerning
and other
Service.
and/or
The
sources for this information
are
adjustments
projections
of needs
for information
made
cycle takes
you
until
Federal
two
how
provided
things change
to
you
survey
Act for
and
legislation
for in the
at
FY
in
Act and
1974
now
review.
The
impacts
possible in the
FY
are
which
available
final
Chiefs Program and Work
pressures
reports which direct
the
for $140 million each
provide
2
Number
6 June
levels.
before
and
Congress
of funds for preparing
sales
its
supporting
specifying purchase
design.
of these actions
1974
time new
time are
will set
drinking water standards
monitoring and regulation of our water systems and
Copies of these actions
that
supporting
its
program
affects
this
go out from Washington
see Field Notes Vol.
1974-1976
reports which prohibit the use
Pending
you
of the Forest
services
the field submit. Projections
years from the time requests
authorization
Appropriations
location
and
in
in
on
data from your reports and from multilevel
historical
Aid Highway Act of 1973 and
year for roads and trails
The
and/or
materials for hearings
activities
the reports
are
interest
specific
use of authorizations
1970 on
backup
engineering
receive an allocation
As examples and of
The
on
based
prepare
sent in by you.
The complete budget
develop.
affecting
legislation
personnel
budget requests for the above programs participate
the
and prepare and coordinate
budget analyses
bills
Engineering
secretary.
and can be secured
will
allotments
Planning
their
by your
Operations
be analyzed and reflected
FY
and provide
for state
use.
to
you
1975 tentative allotments
section
as fully
and
FY
for your
as
1976
Advice.
25
GPO
870-667