Research Report
UKTRP-84-23
PAVEMENT THICKNESS DESIGNS UTILIZING
LOW-STRENGTH (POZZOLANIC) BASE AND SUBBASE MATERIALS
hy
Gary
w.
Sharpe
Rohert C. Deen
Herbert F. Southgate
and
Mark Anderson
Transportation Research Program
University of Kentucky
Lexington, Kentucky
PAVEMENT THICKNESS DESIGNS UTILIZING
LOW-STRENGTH (POZZOLANIC) BASE AND SUBBASE MATERIALS
by
Gary H. Sharpe
Robert C. Deen
Herbert F. Southgate
and
Mark 1\nnerson
Transportation Research Program
University of Kentucky
Lexington, Kentucky
ABSTRACT
This paper presents information whereby laboratory
data
for
pozzolanic
base
and
combinen with elastic layer
criterion
to
determine
subbase
theory
thickness
conventional asphaltic concrete and
A
structures.
also
is
summary
presenten.
of
is
comparison
alternative
crushed
example
presented
and
designs
a
limiting
designs
laboratory
An
determination
of
and
materials
test
may
strain
equivalent
stone
he
to
pavement
testing in Kentucky
thickness
includes
with
asphaltic - crushed stone thickness design.
the
an
design
economic
conventional
INTRODUCTION
NATURE OF POZZOLANIC MATERIALS
The use of pozzolans in
recoroed
history.
of calcined
calcined
cementing
materials
anteoates
Ancient F:gyptians used a cement composeo
impure
gypsum.
The
Greeks
and
Romans
usee
limestone and later developed pozzolanic cements hy
grinding together lime ann a volcanic ash.
The material added to hydraulic cements
to
improve
quality
was
a
loosely
by
the
consolidated
volcanic origin, consisting of various fragments
obsioian,
pyroxines,
"elospar,
pozzolana was first applied to that
term
has
of
material;
of
pumice,
The
nane
however,
the
been extendeo to incluoe not only natural volcanic
materials,
but
siliceous
rocks
diatomaceous
and
earths
artificial
and
themselves,
since
combine with lime
temperatures
they
products.
in
to
the
form
contain
presence
compounds
highly
other
Pozzolans
defined as siliceous materials, even though not
in
rock
etc.
quartz,
Romans
are
cementitious
constituents that will
of
that
water
at
oroinary
possess
cementing
properties.
Naturally occurring pozzolans incluoe clays and
opaline
materials,
and
volcanic
Pozzolans may or may not require
active.
Most
(and
natural
tuffs
calcination
arti fical)
and
to
wastes
and
pozzolans
include
come
fly
from
ash
industrial
(flue
pumicites.
make
pozzolans
grinding to a high degree of fineness to make them
Artifical
shales,
dust),
them
require
suitable.
byproducts
silica
powdered brick, burnt clays and shales, and some slags.
or
fume,
USE OF LOW-STRENGTH MATERIALS
With the escalating costs of materials ann
for
highways
ann
streets,
responsibility of designing
utilizing
byproduct
many
ann
construction
agencies charged with the
constructing
pozzolanic
highways
materials.
(pozzolanic) materials have been used fairly
are
Low-strength
extensively
in
well as abroad.
In
general, pozzolanic materials have been useo to stabilize
an
some
areas
aggregate
source
of
the
base
of
or
lime
Adoitionally,
Uni teo
States
subbase
to
by
adoition
develop
portlano
as
of
fly ash and a
cementitious
a
reaction.
cement or cement kiln dust have been
used to stabilize aggregate subbase and (or) base materials.
Until recently,
highway
ann
the
street
economically
use
construction
competitive
high-quality
of
aggregates.
with
pozzolanic
abunoant
However,
as
the
bases,
stabilized
pozzolanic base materials.
Kentucky
have
situations.
been
~1ixtures
To
used
date,
primarily
supplies
of
costs of proouction
have
of
in
in Kentucky was not often
ann processing aggregate materials
feasibility
materials
increased,
and
has
particularly
pozzolanic
in
so
bases
in
low-volume traffic
that have been considereo recently
anil
evaluateo to some oegree incluoe the following:
•
Lime kiln oust, fly ash, and dense-graded
•
Byproduct lime and oense-graded aggregate;
•
Lime kiln oust, fly ash, dense-graded aggregate,
sand;
•
Lime kiln oust, fly ash, ann limestone mine
screenings (waste material from limestone
2
aggregate;
ann
quarrying operations); and
•
''Scrubber sludge,'' quicklime, and dense-graded
aggregate or pond ash.
Pozzolanic base or subbase materials have been
on
experimental
an
basis
Kentucky, street projects.
Transportation
Cabinet
for
Two
also
a
number
projects
are
of
for
being
utilized
Lexington,
the
Kentucky
Thus,
evaluated.
performance experience currently is limited, but at the
time
evolutionary.
Therefore,
modifications
presented in this report may be required
reflect
additional
experience
and
in
in
the
same
designs
future
performance
of
to
field
projects.
ELASTIC LAYER THEORY OF PAVEMENT THICKNESS DESIGN
Current thickness design procedures for both
flexible
elastic
pavements
layer
histories.
supported
theory
Flexible
by
experience
data.
in
and
over
Kentucky
matched
have
with
rigid
been developed using
pavement
performance
thickness design procedures (1, 2) are
years
40
also
have
of
been
pavement
performance
related to AASHO Road Test
Rigid pavement design procedures (3, 4, 5)
related
to
performance
experience
procedures of the Portland Cement
AASHO Road
~est
have
embodied
Association
in
(~)
failure criterion for flexible
theoretically
determined from
design
the
(7, R).
based on limiting strain criteria.
matching
been
and
Thickness designs in Kentucky (both flexible and
are
and
historical
3
A strain-repetitions
pavements
computed
strains
pavement
rigid)
was
developed
with
performance
by
repetitions
data
and
previous empirical thickness design
pavements,
a
limiting
relaten to
the
mergen
strain
procenures.
criterion
fatigue
For
rigin
was developen and
criteria
of
the
Portlano
Cement Association and AASHTO thickness design procedures.
LOW-STRENGTH BASE AND SUBBASE MIXTURES
MATERIALS
Kentucky
pozzolanic
specifications
mixtures
usen
currently
( 9)
as
base
components
structures to have unconfinen compressive
than
require
of pavement
strengths
greater
600 psi at 7 days when specimens are preparen and curen
in accordance with ASTM
normally
have
(hydra teo
three
lime,
aggregate.
C
593.
Mixtures
components:
quicklime,
or
used
for
bases
fly ash, a source of lime
lime
kiln
oust),
and
an
Cement or cement kiln oust have been substituteo
for the lime source.
Pozzolanic mixtures useo as subbases are
required
to
have
strengths
as
great
There are no strength requirements in
applications.
Recent
not
generally
as those for bases.
Kentucky
for
subbase
experience on one project resulteo in
compressive strengths in the order of 300 psi at 7 days
cured
according
to
ASTM
c
potential as a subbase material
the
laboratory:
l) scrubber
593.
Two
have
mixtures that have
been
sluoge,
investigated
aggregate,
strengths
of
300
to
600
psi
lime.
at 7 days when
cured according to .1\.S'l'M C 593 have been obtained.
4
in
and some
form of lime and 2) aggregate stabilizeo with baghouse
Compressive
when
Fly Ash
The properties of
sources
and
facility
properties
under
properties
fly
of
ash
of
will
burned
coal
consideration.
dependent
vary
The
upon
at
the
specific
range
of
typical
fly ash are illustrated in Reference 10.
fly ash is silt-size spherical particles 0.015
to
0.050
The
mm
in diameter.
Sources of Lime
Commercial sources of lime
material
use
as
a
stabilizing
quicklime and hydrated lime.
Most highway
agencies specify that lime materials shall meet
requirements
of
include
for
ASTM C 207, Type N.
Typical properties of limes used for
stabilization are summarized in References 10 and 11.
The characteristics of lime and cement
dependent
significantly,
vary
producing
physical
Typical
location.
properties
of
cement
reported elsewhere (12).
for
laboratory
upon
kiln
dusts
may
for
each
composition
and
specifics
ranges
of
and
lime
Lime kiln dusts
kiln
used
dusts
in
are
Kentucky
and field analyses were within those typical
ranges.
Scrubber sludge is a waste material obtained
use
of
scrubbers
to
remove
fly
ash
and
coal-burning processes of electric generating
Scrubber
sludqe
(flue
with
residue
power
sulfite.
the
cake
is
a
from
plants.
gas desulfurization sludgel consists
of fly ash and a lime dust slurry filter cake material.
filter
the
compound
of calcium sulfate and calcium
Quicklime or hydrated lime
sludge for stabilization.
5
The
normally
is
added
to
Stabilization reactions begin
almost immecUately after the combination of fly ash and
lime
to the dewatered sludge.
Aggregates
for
Aggregates
mixtures
that
both
have
base
and
limestone
gravels.
quarrying
in
the
aggregate
for
a
Kentucky
has
ash
laboratory
subbase.
been
mine
screenings
operations\,
Additionally, pond
evaluated
pozzolanic
been investigated included dense-graded
limestone aggregates, limestone
of
subbase
and
The
dense-grac'!ed
(byoroduct
river sand, slag, and
waste
may
material
be
an
predominant
limestone.
has
been
appropriate
aggregate
Specifications
for dense-graded aggregates ann gravel bases in Kentucky
summarized in Table l
Two
aggregate
types
of
Cabinet.
(Kentucky
aggregate
dense-graded
limestone
and pond ash (also called bottom ash)
The
have been
dense-graded
meet specifications of the Kentucky Transportation
Gradation tests as well as a slake-durability
method)
for
specifications
dense-graded
aggregate
gradations and characteristics of a pond
facility
in
base)
ash
of
amount
plus
(outside
as
well
material
specifications
pond
ash
might
as
from
There
for
l-inch material for the pond ash.
The large size of the coarse particles is an indication
the
The
Gradation
Kentucky are presented in Figure 1.
was a disproportionate
compacted
test
(14) were performed on the pond ash.
slake-durability test resulted in 5 percent loss.
one
are
(13).
used to prepare sludge-aggreaate mixtures.
aggregate
in
that
be more suitable as a subbase material
than as a base material.
6
SPECIMEN PREPARATION
All specimens for this study were
accordance
with
4.6-inch molds.
use
ASTM
C
593(79)
Deviations from
prepared
in
that
in
4-inch
general
diameter
method
involved
by
the
of a 5.5-pound hammer and a 12-inch free fall instead of
the
specified
10-pounn
Moisture-density
hammer
Hi-inch
ann
relationships were determineil in accordance
with ASTM D 698(79) instean of A.STM D l'i57(79).
density
drop.
Maximum
dry
and optimum moisture content were determined using a
A
polynomial curve-fitting procedure.
smoothing
technique
was used to eliminate localized changes in concavity.
Initial mixtures
particles,
and
specified in
coarse
high
percentages
of
fine
compaction procedures were varien from those
AST~1
mixes.
containen
C 'i93(79), which
Even
though
are
more
subsequent
coarser mixes, compaction techniques were
applicable
to
specimens involved
kept
constant
so
direct comparisons of engineering properties could he made.
All specimens prepared for or obtained from base
mixtures
were
submerged in water for 4 hours before testing
for compressive strengths, as required
If
slaking
course
occurred,
then
the
proportions were eliminated from
by
ASTM
C
593(79).
materials and (or) mixture
consideration
as
pavement
components.
The only deviations from ASTM C 593 (79)
aggregate-scrubber
sludge
occurred
mixtures were tested.
It was not
possible to submerge sludge specimens, because some began
slake
immediately
upon submergence.
to
Slaking also prevented
vacuum saturation or freeze-thaw testing.
7
when
Strength
testing
of scrubber sludge was performed without
deficiency,
while
considered
submergence.
acceptable
for
material
proposed as a subbase where confinement is provided
and
pavement
construction.
at
curing
layers,
is
ASTM
~CJ3(79)
100 F
conditions
C
in
included
a
and
research
necessary
variations
ambient
also
container.
and
curing.
Other
curinq
combinations
of
additional
specifications
adequately
to
base
accelerated
Certainly,
develop
by
for base course
specifies
curing
to
thereof
appropriate
sealed
ambient
accelerated
is
not
This
reflect
and
needed
characterizations of materials for specific applications.
TESTING
Unconfined compressive strength tests (ASTM
splitting
compressive
strength
C
469(65))
tests,
A
computer
were
with
deflection
(see
axial load and axial deformation data.
computer
solution,
dial
program was developed to calculate and
plot the static-chord modulus of elasticity
from
oerformed.
additional information
was obtained by measuring deformation
gauges.
39(72)),
tensile strength tests (ASTt1 C 496(71)), and tests
for static-chord modulus (ASTM
During
C
the
modulus
was
Figure
2)
To facilitate a
calculated
by
a
four-point least-squares fitting technique.
Attempts
during
were
compressive
obtaining
estimated.
data
made
to
measure
lateral
deformation
strength
testing
for
purpose
of
could
be
from
Poisson's
which
Poisson's
stress-lateral
ratio
ratio was estimated from the ratio of
the slopes of the axial stress-axial
axial
the
strain
8
curves.
strain
curve
Techniques
and
used
the
to
measure lateral strains, however, nio not produce
ann
reliable
results.
Therefore,
searched to determine the
values
from
to
0.08
percentage of the
ratio
(16)
of
mixtures
of
literature
others
was
15);
(10,
0.3, dependent upon stress level as a
were
ultimate,
indicated.
A
Poisson's
was assumed for all pozzolanic base mixtures
0.15
until
experience
the
consistent
sufficient
couln
he
recent laboratory
reliable
test
data
A
summary
accumulateo.
analyses
in
Kentucky
for
Kentucky
of results of
are
presented
in
Table 2.
PAVEMENT THICKNESS DESIGN
DESIGN METHODOLOGIES
Structural Number
Other agencies have
pozzolanic
base
materials
Guide for flexible
considerable
layer
developed
for
pavement
layer
coefficients
for
use with the AASHTO Interim
(7 ) .
design
There
has
been
discussion regarding the use and reliability of
coefficients
comparen
with
more
rationally
haseo
design systems have been advocated by others.
A
review
variability
of
literature
among
has
suggesteo
layer
pozzolanic materials (10, 17, 18).
coefficients
varies
from
indicated
The
0.20
to
coefficients
range
are
mixtures.
recommenned
Lesser
for
values
lower
subbases.
9
of
0.44
recommendations in the order of 0.28 to 0.30
base
consioerable
for
for
suggested
with
most
pozzo1anic
for structural coefficients
strength
materials
used
as
Stress Ratio
Other thickness design procenures
criterion
of
use
a
failure
relating the ratio of flexural strength to modulus
rupture
Flexural
(19)
as
a
function
of
repetitions
failure.
to
strength and modulus of rupture are determine<'! from
laboratory tests and analyses.
ELASTIC MODULUS FOR POZZOLANS
Early thickness designs utilizing pozzolans in
were
restricte<'l
to low-volume city street applications (201
an<'l related well to other
evaluations
using
design
thickness
static-chord
modulus)
applications
resulted
in
applie<'l.
Comparisons
other
with
reasonable
correlations
variations
for
somewhat
to
and
same
(based
city
on
street
unrealistic
high-fatigue
thickness
design
levels.
design methodologies also indicated
at
low
field
fatigue
levels
applications.
elastic-laver
laboratory
The
procedures
low-fatigue
high-fatigue
was concern that
methodologies.
design
for
requirements when
some
Kentucky
parameters
analyses
but
However, there
determined
did
wide
not
from
completely
account for the characteristics of pozzolanic materials.
A literature review indicated a wide
moduli
of
elastic
for low-strength hase and subbase materials dependent
upon specific proce<'lures used to
All
range
determine
the
parameters.
studies reviewed indicated increasing elastic moduli for
pozzolanic
materials
compressive
strength
magnitudes
of
elastic
proportionate
and
(or)
moduli
similar compressive strengths.
10
to
increases
tensile strength.
did
vary
in
However,
considerably
for
Initial estimates of elastic moduli in this
determined
by
the
Figure
were
static-chord method (ASTM C 460(65)) and
generally were relatively low (30,000
(see
study
3).
Elastic
psi
to
300,000
psi'
moduli for lime-fly ash mixtures
reported in Reference 10 were on the order of 100,000 psi
500,000
psi
Figure
for similar levels of compressive stresses (see
Even
3) •
(1,600,000
to
psi
greater
to
magnitudes
3,300,000
psi)
of
have
elastic
been
moduli
reported by
others (12).
Least-squares regression analyses were used to
trends
of
modulus
of
elasticity
compressive strength and tensile
sources
the
of
data (Figure 3).
static-chord
developed
the
indicated
greatest
stress
a
FHj,~A
repeated
various
The Kentucky relationship (for
is
most
rate
conservative
and
was
while
data
from
the
report ( 12) are resilient
testing
(lime
and
for
cement
illustrate trends of
unconfined
a
range
of
of
dusts).
resilient
modulus
strength
determined
fly
ash
as
and
a
splitting
proportions
were
and
4
of
tensile
developed
components.
moduli presented in Table a of Reference 10
11
3
kiln
function
for
or
and
Figures
Additional plots have been
mixture
by
fly ash-kiln dust
strength for all data.
specific
report
Data presented
moduli
kiln
compressive
report
NCHRP
somewhat lesser rate of change.
load
FHWA
of change of modulus per unit_ of
ratios and also a variety of sources
dusts
the
Resilient moduli presented in the
compressive
in the
for
for a number of pozzolanic hase mixtures evaluated
in Kentucky.
showed
modulus)
unconfined
versus
strength
evaluate
Elastic
determined
from
plate
load
Median
tests.
moduli
compressive
and
strengths
were used to develop the relationship presented in
Figure 3.
The relationship of
modulus
of
elasticity
based
synthesis was selected as
to
determine
compressive
a
strength
versus
on data reported in the
"middle-of-the-road"
design elastic moduli.
~CHRP
criterion
Additional research is
necessary to verify and refine this design criterion.
Kentucky
469(65)
laboratory
and
analyses
based
on
ASTM
C
resultino values were essentially static moduli
of elasticity.
A Model 400 Road Rater
deflection
measurements
pavements.
Deflection
variability
and
detail.
were
are
However,
from
used
to
in-service
data
currently
was
pozzolanic
indicated
being
preliminary
obtain
considerable
evaluated
in
analyses
more
indicate
back-calculated moduli of 1,000,000 to 3,000,000 psi.
1\hlberg and Barenburg ( 15) reported flexural
elasticity
from 1,500,000 to 2,500,000 psi.
reported by Collins and Emery (12)
3,300,000
psi.
varied
of
of
Resilent moduli
from
370,000
to
Others (10) have reported ranges of modulus
from 100,000 psi at a compressive strength of 400
modulus
moduli
500,000
psi
psi
to
a
at a compressive strength of 1,000
psi.
The modulus of elasticity of asphaltic
as
a
function
concrete
varies
of temperature and frequency of loading (21,
22).
On the
have
relatively constant moduli for frequencies of 0.1 to SO
Hz (23).
linear
other
hand,
granular
cohesionless
For a soil that may be considered to
materials
behave
as
a
viscoelastic solid, the elastic modulus is a function
12
of
frequency
Hardin
(24).
demonstrated
and
Black
variations
dramatic
26)
( 2 5.
of
elastic
moduli
cohesive soils at low frequencies (less than 0.1 Hz)
of
creep
phenomena.
This
partially
explains
variations in elastic moduli from static and
Futhermore,
it
also
has
been
of
because
observed
dynamic
demonstrated
have
tests.
that
modulus
varies as a function of strain amplitude (23, 25, 26),
which
varies considerably among test procedures.
Static moduli were
actual
traffic
not
loading
considered
representative
Resilient
conditions.
moduli are
determined on the basis of repeated load tests at l to 2
Road
Rater
deflections
were
obtained
at
25
600-pound force dynamic load and a 1,670-pound
load.
Others
(15)
both
frequency
at
is apparent.
procedures,
Benkelman
deflections
beam
using a
static
strain
this
amplitude
time
of
for
actual
conservative
of
traffic
design
Additionally, Kentucky thickness design
while
strain-repetitions
force
Hz.
estimated elastic moduli from tests for
and
loadings, the need
moduli
Hz
In view of the significant variations
flexural strength.
for
predicated
criterion,
defelection
were
on
verified
behavior
limiting
a
initially
where
by
rebound
were obtained at low (creep) vehicle speeds (0.5
to 1.0 Hz) for an
18,000-pound
with
deflections
theoretical
axleload
calculated
were
matched
using the Chevron
N-layer program (27).
Thus, an
compressive
and modulus of elasticity is presented
strength
in Figure 3.
13
interim
and
criterion
relating
SUGGESTED DESIGN METHODOLOGY
Kentucky
Thickness design procedures in
rigid)
been
have
limits
the
on
criteria.
strain-repetitions
criterion
developed
basis
of
concrete
(l, 2, 28)
criterion
at
the
bottom
(Figures S and 6).
(3,
4,
in
5)
versus repetitions for various
elasticity
and
pavement
vertical compressive strains at the top of
pavement design criterion is an expression of a
fatigue
and
limiting
flexible
The
the subgrade and the tensile strain
asphaltic
(flexible
modulus
of
used to develop a tensile
terms
the
The rigid
stress-ratio
of tensile strain
combinations
rupture.
of
of
moc'lulus
of
The same approach was
strain-repetitions
criterion
for
pozzolanic base materials (Figure 7).
For the
stress
to
pozzolanic
material,
ratio
of
flexural
compressive stress at failure was estimated to be
0.2S at the ultimate compressive
current
the
Kentucky
specifications
strength
of
a
( 15) .
Based
minimum compressive
strength of 600 psi, the flexural stress for pozzolanic
materials
is
elasticity
from
Poisson's
ratio
150
psi.
Figure
of
The
minimum
desian
is
250,000
psi.
3
0.15
for
on
modulus
The
base
of
assumed
pozzolanic materials (16) is
near the value used to
develop
rigid
Kentucky.
of
fatigue envelope used by the
"'he
shape
the
pavement
designs
Portland Cement Association (6) for portlanc'l cement
pavements
was
applied
repetitions
of
an
of
allowable
18,000-pound
tensile
stress
to
single axleload (3, 4, 5).
The allowable tensile stress versus repetitions
14
concrete
pozzolanic materials and defines
to
the relationship of ratio
in
relationship
for pozzolanic materials is the Portland
Cement
Association
curve shifted according to the following relationship:
= (Flexural Strength) x (Stress Ratio)
Tensile Strain
+(Modulus of Elasticity)
where the stress ratio value corresponds to a specific
for
repetitions
of
an
lR,OOO-pound
equivalent
value
axleloan.
More specifically, for pozzolanic base mixtures,
= (150 psi) x (Stress Ratio)
Tensile Strain
+
The above
stress
the
equations
ratio
to
pozzolanic
criterion,
convert
allowable
base
when
(250,000 psi).
in
(see
of
allowable
7).
Figure
The
resulting
to one proposed by Thompson (19),
compared
Kentucky
ratio
tensile strain at the bottom of
is slightly more conservative.
pavements
the
has
Experience
been
with
limited;
pozzolanic
the
proposed
criterion also may adjustment based on field performance.
Recent studies (3, 4, 51 have involved
of
work
and
energy
principles
to
components into a single resultant.
is
the
energy
at
a
point
to
combine
Strain
load
and
is
in
structure
pavement
must
by
the external force.
or work, at a given location
used
as
the
density
equal
and
basis
of
within
design
15
each
point
he summed (integrated) to
obtain the total strain energy, which would equal
caused
strain
the WORK at that point, as defined by classical
The strain energy density for
work
all
energy
physics (29, 30).
the
application
in a body to resist the energy
imposed on that body hy an outside
opposite
the
the
total
Strain energy density,
the
rather
structure
may
be
than using a single
strain, such as
criterion.
the
vertical
compressive
strain,
of thickness
utilizing
proce~ure
rigi~
the
bases
pozzolans
in
pavement structure, the elastic layer theory embodien in
the Chevron N-layer computer nrogram 127) was
c'letermine
thickness
requirements
(l/3 asphaltic concrete
tranitional
an~
2/3
for
asphaltic
use~
~irst
to
conventional designs
crushed
stone
using
basel
presentee'~
materials based on criteria
c; ann 6 ( 1, 2, 281 .
the
the
~esigns.
To develop a design
the
an~
Recent investigations of both flexible
pavements have utilizen concepts of equal work as
as
in Figures
1qork at critical locations -- bottom
of
concrete and (or1 top of the subgrade -- were
determined ann used as the controlling fatigue value for
the
respective materials at their critical locations.
Elastic layer theory then was usen to netermine
and
work
varying
strains
for a matrix of thicknesses of pozzolanic base (of
mor'!uli
thicknesses
of
of
elasticity)
asphaltic
those analyses were
user'!
combined
concrete
to
with
surfacino.
develop
a
series
several
Results of
of
oraphs
similar to Figures R ann q.
Determination
design
of
an
equivalent
structural
thickness
utilizing pozzolans may he determined by matching the
critical strains ann work for a conventional pavement
with
companion
work
and
strains
thicknesses of asphaltic concrete
base.
The
work
usen
in
some combination of
surfacing
and
pozzolanic
and the vertical compressive strain at the
top of the subgrade for the control
were
for
nesign
combination
16
with
(conventional)
pavement
Figures 8 and q (and other
similar graphs) to determine thicknesses of pozzolanic
corresponding
specific
to
elastic
moduli
thicknesses of asphaltic concrete surfacing.
pozzolanic
bases
will
criterion based on
strain.
work
slightly
compared
to
various
Thicknesses
increased
vertical
of
using
a
compressive
Resultant thicknesses of pozzolanic bases were used
to develop Figure 10.
base
be
and
bases
may
then
be
The specific thickness
determined
dependent
of
pozzolanic
upon
the desired
modulus of elasticity and the desired thickness of
concrete
surfacing.
asphaltic
Modulus of elasticity may be related to
compressive strength hy Figure 3.
Design thicknesses (based on the work at the top of
subgrade)
were
checked
criterion (Figure
asphaltic
6)
concrete
bottom of the pozzolanic
fatigue
of
the
2R)
2,
the
at
the
bottom
of
the
limiting tensile strain at the
base
(Figure
7)
to
verify
that
asphaltic concrete and pozzolanic base were
not controlling.
tensile
against the limiting tensile strain
( l.
and
the
Experience
in
Kentucky
has
shown
that
strain at the bottom of the asphaltic concrete layer
is normally not the controlling design criterion because
relatively
magnitude
"stiff"
of
moduli
tensile
of
strains
pozzolanic
at
the
bases
interface
the
limit the
between
asphaltic concrete and pozzolanic base.
EXAMPLE DESIGN
Phase
I
of
determination
of
asphaltic concrete
the
design
thickness
pavement.
following design conditions:
17
procedure
involves
the
requirements for a conventional
Consider,
for
example,
the
Design lR-Kip EAL's
=
5,000,000
nesiqn Suhgrade = CBP 9
Using
Kentucky
thickness
<'lesiqn
curves,
conventional
a
asphaltic concrete pavement woul<'l be as follows:
=
Asphaltic Concrete Surface and (or) Base
=
Dense-graded Aggregate Base
In
Phase
pozzolanic
base
14 inches
structurally
II,
equivalent
materials are determine<'!.
an<'! work for conventional <'lesigns are
Chevron
N-layer
Limiting
strains
structures
may
computer
be
to
Analyses
Critical strains
(Fiqures
those
design
obtained
from
is
an
3).
(Figure
Three
Table 3, which
using
the
and
91.
R
of
conventional
of
a
thickness
number
of
of
concrete
The
specific
based
on
estimated
analyses
of
compressive
alternative
illustrates
also
designs
the
asphaltic
asphaltic
thicknesses may be used to develop Figure 10.
thickness
using
used to determine thickness requirements
for pozzolanic bases for a constant
concrete.
designs
determined
program
corresponding
7 inches
elastic
mo<'lulus
strength
data
are summarized in
economic
comparisons
with conventional designs.
ECONOMICS OF THE USE OF POZZOLANIC MATERIALS
The
major
pozzolanic
base
benefit
is
the
associated
with
substitution
the
of
use
structure.
advantageous
asphaltic
as
Pozzolanic
alternatives
concrete
pavements
18
to
bases
very
a
a less expensive
material for a portion of a more expensive component
pavement
of
may
thick
be
of
the
especially
conventional
or thick full-depth asphaltic
concrete pavements where deep
Pozzolanic
problem.
bases
alternative for some rigid
rutting
also
may
may
be
be
potential
a cost effective
This,
pavements.
a
has
however,
not been considered in Kentucky.
Table
3
conventional
summarizes
an
economic
asphaltic
concrete
pavement
theoretically equivalent thickness designs
bases.
Thickness
designs
for
the
the
pozzolanic
material;
this
are
actual
three
pozzolanic
pozzolanic
bases were
of
350,000
psi
corresponds to a 7-day
compressive strength (ASn1 C 593 curing)
quantities
with
a
using
determined on the basis of a design modulus
for
of
comparison
of
800
psi.
The
quantities for a project for which a
pozzolanic base is being considered.
OTHER FACTORS
EFFECTS OF CURING
Effects
deflection
of
curing
were
detected
Table
measurements.
4
in
presents
the
a
field
summary of
deflection data obtained directly on a 6-inch layer
kiln
dust - fly
2
were
fly ash,
ann
proportions
for
percent fly
ash,
Field
for
deflection
all
Desicrn
the same:
84
sites:
of
lime
ash - dense-graded aggregate base for three
city street projects.
Site
by
oense-gradeo
were
3
and
for
Site
l
and
8 percent lime kiln dust, R percent
percent
Site
proportions
88
6
percent
aggregate.
Design
percent lime kiln dust, 6
dense-graded
aggregate.
measurements were obtained at similar ages
7
to
q
19
days
after
placement.
Prior
laboratory and field data indicated subqrade conditions
were
similar for the three projects (CBR 4).
Site l was placed in mid August
were
curing
Site
2
was
placed
were much cooler
was
membrane
was
was
in
(40 F
in
cool
membrane,
locations.
condition.
in early November when air temperatures
to
60 F).
The
early
and
Hay.
Air
bituminous
curing
Site
temperatures
rainfall was recorn setting.
was drenched immediately after placement
curing
good
not placed immediately after compaction.
placed
unseasonably
was
conditions
very favorable -- temperatures ranged from 60 F to 80 F
and the bituminous curing membrane
3
and
of
the
were
Site 3
bituminous
and the membrane was "washed" away in some
In those areas, the surface of
unbounn or poorly hounc1.
the
base
course
The site also was subjected to
significant rainfall nuring the initial 7-day curing
period.
It
greater
is
apparent
from
the
strengths resulted
for
more
Deflection
also
data
deflection
favorable
indicated
bituminous curing membrane on proper
nata
that
curing
the
conditions.
influence
curing
and
of
the
associated
strength gains.
Both laboratory (Table
indicated
that
?)
and
field
data
(Table
high temperatures and moisture retention are
primary contributors to good curing and associated
strength.
Thus,
placement
gains
60 F
for
at
least 7 days.
20
greater
Placement of a bituminous
curing membrane is apparentlv essential for
of high early strengths.
in
of pozzolanic base materials is
recommended when air temperatures are expected to be
than
4)
the
development
AUTOGENOUS HEALING
Another aspect associated with
base
materials
the
is
overlying
anticipate!}
pozzolanic
the potential for reflective cracking of
asphaltic
that
low-strength
concrete
greater
amounts
surfacing.
of
It
cracking
is
will occur
during curing of hi9her-strength pozzolans.
Results of the deflection
sites
reported
above
testing
of
the
dust - fly
ash - dense-graded
room
temperature
A series of
for 2R days.
cylinders
B.
sand
Mixture
high
by
for 7 days).
psi
4.6-inch
Compressive
not
to
ASTM
C
cured to an age
subjected
to
of
240
Mixture
B.
were
in
those
days.
sealed
The
compressive testing.
that time were 870 psi
for
Significant
Mixture
strength
21
593
diameter cylinder cured at 100 F
strengths
but
of
That was considerably less than
cases
for Mixture A and 1,194 for Mixture B.
destroyed,
42
The
each
were
The 6- by
12-inch cylinders tested for compressive strengths at 7
were
for
contained
percent
for specimens compacted and cured according
1,501
psi
and 42 percent limestone mine screenings.
ash and lime kiln dust.
(4-inch
209
B
fine portions of both mixtures contained R
fly
curecl
The aggregate portion for Mixture A consisted of
84 percent dense-graded limestone;
percent
and
Compressive strengths of
those specimens were 231 psi for Mixture A and
Mixture
lime
aggregate mixtures were
prepared in fi-inch cliameter by 12-inch
at
test
stimulated additional interest in the
effects of curing and autogenous healing.
kiln
three
days
in plastic bags and
cylinders
were
again
Compressive strengths at
A
and
gains
1,367
may
psi
for
be partially
attributable to long-term strength
pozzolanic
materials
and
also
gain
characteristics
autogenous
healing
of
of the
initial failure locations.
Autogenous healing apparently occurs in pozzolanic
specimens
if
left
undisturbed and curing conditions remain
favorable.
However, conditions
duplicated
by laboratory conditions.
in
the
field
may
traffic
loadings.
not
he
Autogeneous healing of
cracks in field installations may he slowed by the
under
base
Field
curing
stressing
conditions
(temperature and moisture) also may vary considerably.
CLOSING COMMENTS
Experience in Kentucky relative to the
life-cycle
costs
nonexistent.
pavements
of
pozzolanic
Thickness
have
been
pavements
design
developed
which
represented
be
determined
paper represents
design
to
methodology
performance
laboratory
pozzolans.
herein
initial
may
efforts
pozzolanic
Kentucky
to
at
conditions
are
this time.
develop
a
This
thickness
for pozzolanic pavements that is related
histories
test
for
by other agencies for other
to
not
and
almost has been
procedures
regions, but the extent
could
performance
data
in
Kentucky
characterizing
It is anticipated that the
as
well
the
properties
procedures
as
to
of
presented
be the nucleus for the development of a complete
set of thickness design
curves
using
pozzolanic
or
other
low-strength base materials.
Additional
life-cycle
costs,
research
and
durability
22
experience
of
materials,
relative
to
fatigue-shear
strain
relationships,
necessary
to
refine
thickness design.
and
are
and
being
pavement
performance
procedures
and
will
he
methodologies
for
Pavement sections are currently
monitored
analyses
and
indicate
competitiveness
to
refinements.
provide
place
such data for future
Economic
with
in
analyses
other
apparently
materials for initial
construction.
A major criticism of
reflective
cracking
pozzolanic
pavements
are
significant
layers
to
of asphaltic concrete layers associated
with shrinkage cracking in the pozzolanic
evaluations
relates
currently
potential
ongoing.
involves
the
base.
One
use
Additional
technique
of
with
stress-relief
between the pozzolanic and asphaltic concrete layers.
Benefits are yet to be determined.
REFERENCES
Havens, ,J. H.; Deen, R. C.; and
''Design
Guide
Southgate,
Report
Research
Program,
UKTRP-81-l 7,
Kentucky
of
Transportation
University of Kentucky, Lexington, August
Southgate, H. F.; Deen, R. C.; and
a
Thickness
Concrete Pavements," Research
Transportation
F. ;
for Bituminous Concrete Pavement Structures,''
Research
"Development
H.
Research
Desiqn
Report
Program,
Havens,
,J.
H.;
System for bituminous
UKTRP-81-20,
University
of
Kentucky
Kentucky,
Lexington, November 1981.
3.
Newberry,
Southgate, H. F.; Havens, J. H.; Deen,
D.
c.
Jr~
"Development
23
of
a
R.
c. :
and
Thickness Design
System for
Report
Portlann
Cement
Concrete
Pavements,"
Research
UKTRP-83-5, Kentucky Transportation Research Program,
TJniversity of Kentucky, Lexington, February 1983.
4.
Design
Southgate,
Curves
H.
for
ano
F. ;
Portlano
Deen,
Cement
c.
R.
"Thickness
7
Concrete
Pavements,''
Research Report TJKTRP-84-3, Kentucky Transportation
Research
Program, University of Kentucky, Lexington, February 1984.
5.
Design
Southgate,
Proceoure
H.
for
ano
F. ;
Portland
Deen,
c. ;
R.
"Thickness
Cement Concrete Pavements,''
Research Report UKTRP-84-6, Kentucky Transportation
Research
Program, 1Jniversity of Kentucky, Lexington, March 1984.
6.
"Thickness Design for Concrete Pavements,"
PortlanCI
Cement Association, Skokie, Il, 1966.
7.
American
Interim Guide for
Association
of
Design
State
of
Pavement
Highway
Structures,
ano Transportation
Officials, Washington, DC, 1972 and 1981.
Fl.
Special
The AASHO Road Test
Report
Report
5,
Pavement
Research,
6lE, Highway Research Board, Washington, DC,
1962.
9.
Special
Provision
83(70),
"Fly
Ash
Stabilized
Bases," Kentucky Transportation Cabinet, Frankfort.
10.
National
Highway
Lime - Fly
Cooperative
Practice
No.
Ash - Stabilized
Highway
37,
Bases
and
Subbases,
Research Program Synthesis of
Transportation
Research
Board,
Washington, DC, 1976.
ll.
Chemical Lime Facts,
National Lime Association, 1973.
24
Bulletin
214,
3rd
Edition,
12.
Ash
Collins, R. J. r and Emery, J. J.; ''Kiln Dust
Systems
for
Highway
Bases
FHWA/RD-82/167, Federal Highway
and
Fly
Subbases," Report No.
Administration,
Washington,
DC, September 1983.
13.
Standard
Construction,
Specifications
Kentucky
for
Road
Transportation
and
Bridge
Frankfort,
Cabinet,
l 983.
14.
"Slake Durability Innex Test," Method KM-64-513-
76, Kentucky Transportation Cabinet, Frankfort, 1976.
15.
Ahlberg, H. L.; and Barenburg, E.
Pavements,''
Engineering
Experiment
11
Station
Pozzolanic
Bulletin
473,
University of Illinois, Urbana, 1965.
16.
Barenburg, E. J.; ''Lime-Fly Ash-Aggregate
Mixtures
in Pavement Construction,'' National Ash Association, 1974.
17.
Gomez,
Coefficients
and
M. i
and
Thompson,
Thickness
M.
"Structural
R. ;
Equivalency Ratios," University
of Illinois, Urbana, June 1983.
18.
of
Larson, T. D.; and Lindow, E.
s.
"An
i
Evaluation
Pennsylvania's Flexible Pavement Design Methonology," The
Pennsylvania
Transportation
Institute,
The
Pennsylvania
State University, State College, December 1974.
19.
Thompson,
Nondestructive
M.
R.
Testing
i
"Concepts
Rased
for
Asphalt
Developing
a
Concrete
Overlay
Thickness Design Procedure," University of Illinois,
Urbana,
June 1982.
20.
Sharpe, G. W.; Southgate, H. F.; and Deen,
"Development
Rase
of
Materials,"
R.
Pavement Thickness Designs Using Pozzolanic
Research
25
Report
UKTRP-83-25,
Kentucky
Transportation
Research
Program,
llniversity
of
Kentucky,
Lexington, October 1983.
21.
B.
Kallas,
Properties
of
F.;
Asphalt
and
Riley,
c. ;
J.
"Mechanical
~laterials,"
Pavement
Proceedings,
Second International Conference on the Structural
Design
of
Asphalt Pavements, University of Michigan, Ann Arbor, 1967.
22.
Shook,
J.
F.;
Influencing
Dynamic
Proceedings,
The
and
Kallas,
Modulus
of
Association
B.
"Factors
F. ;
Asphaltic
of
Concrete, ''
Asphalt
Paving
Technologists, Vol 38, 1969.
23.
Drnevich, V. P.; and
Saturated
Sands
to
Jent,
J.
P.;
"Response
of
Cyclic Shear at Earthquake Amplitudes,"
Water Resources Research Institute Report No. 87,
University
of Kentucky, Lexington, October 1975.
Richart, F. E., Jr.; Hall, J. R., Jr.;
24.
R.
D.;
Vibrations
and
Woods,
of Soils and Foundations, Prentice-Hall,
Inc, Englewood Cliffs, NJ, 1970.
25.
Modulus
Hardin,
of
Mechanics
B.
0.;
and
Black,
w.
L.;
Normally Consolidated Clay," Journal of the Soil
and
Foundation
Division,
Vol
94,
American Society of Civil Engineers, New York,
26.
"Vibration
Hardin, B.
Modulus
0.;
of
and
Black,
w.
)\To.
~1arch
L.;
SM2,
1968.
Closure
to
Normally Consolidated Clay," Journal
of the Soil Mechanics and Foundation Division,
SM6,
"'Vibration
Vol
95,
No.
American Society of Civil Engineers, New York, November
1969.
27.
Michelow,
Displacements
in
J.
an
"Analysis
i
N-layered
26
of
Stresses
and
Elastic System under a Load
Uniformily Distributed on a Circular Area," Chevron
Research
Corporation, Richmond, Ca, September 1963.
28.
Deen, R. C.; Southoate, H. F.; and Havens,
"Structural
Research
Analysis
Report
of
Bituminous
Division
305,
Concrete
of
J.
H. ;
Pavements,''
Research,
Kentucky
Department of Highways, Lexington, May 1971.
29.
Sokolnikoff,
Elasticity,
Second
s. ;
I.
Edition,
Mathematical
Theory
of
McGraw-Hill Book Co, New York,
1956.
30.
11
The
Deen, R. C.; Southgate, H. F.; and
Effect
Proceedings,
of
The
Truck
Design
Association
Technologists, Vol 49, l9RO.
27
on
Mayes,
Pavement
of
J.
G. ;
Performance,"
Asphalt
Pavinq
SIEVE SIZES
0
0
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LEGEND
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POND ASH
CHARACTER! STICS
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.. .
DIRMETER,
Gra~ation
~gu~~~~:~
•
t. 01 lOS!
UNIT Nf.JGHh 1!2, D I"Cf
NEAft "' 2t. !I LOSS
.
~-r-,, r-~~~~
!lAND,.
SAND
1 D"
1 D'
Figure 1.
...~
''
\
0
,fb '),.'!>
\
\
Zco
,t>
'
SILT
,.,
10"'
1 D·'
MM
Curves -- nense-Gra~e~ Limestone
an~ Pond Ash Material.
Aqqregate
SRMPLE NUMBER
84% DGR.
8% FL YRSH,
13
8% KILN DUST
PREPARED : 2-7-84
CURED
28 DA'!'S
0
0
HAXIHUM COMPRESSIVE STRESS • 2929 PSI
------------------.-+- ...,.._ __
0
..... ""
(/")
0....
I
/
,..
I
~'-~'
...."-/'
:?I
.,
"?"*;/
•I
..
"-/
/.
I
.....
/
/
t!l
z
w
/
.
I
/
•
,I# e
0£---~~--~~--~~--~~--~------.
D
Figure /.
D. 2 D. 4 D. 6 D. 8 !. D !. 2
ENGINEERING STRR IN, /.
Example Determination of
Moc1ulus.
Static-Chor~
LEGEND
FHWA DATA 1121,
TABLES 25 AND 31
C)= NCHRP DATA 11Dl,
TABLE 9, MIDRANGE
KTRP
DATA, TABLE 2
"" =
[!]=
0
0
....0
Figure 3.
Modulus of Elasticity versus Compressive
Strength for Various Data Sources.
[!]
=
LEGEND
FHWA DATA 1121,
TABLE 31
r.n
:::J
_J
:::J
0
m
oo
::t:O
0
o-N
z
w
_J
r.n
w
c: o¥----.---~-~~-~---.
D
D. 1 D. 2 D. 3 D. 4 D.S
TENSILE STRENGTH, KSI
Fiqure 4.
Resilient Modulus as a Function oF
Splitting Tensile Strength.
~a:~
u~
.-a:b
.~.
1-1.. ,.,o::c,;---1roo"•--1...,.,0,-;',-----1roo·'--.1' o•
18-KIP EQUIVALENT AXLELOAO
ffi ~ l+0~,--1_,.0__,1,-l
>
Fiqure S.
t
Limitinq Suhqrane Vertical Compressive Strain
versus Repetitions of an lR,OOO-pounn Axleload.
~
zD
~a:
a:~
f-'
~
<f1
UJ
-
-I
-'·
<f1 0
AC
lK 5 I l
F==::::::::::::~~M~OOULUS
zw
f-~
uD~--.....-,-l
a:
1
Figure 6.
o'
t
150
270
600
1eoo
~~-~~-........,~-~-~
1 o•
1'o•
1'o•
1'o•
1'o'
1'o•
18-KIP EQUIVALENT AXLELOAO
Limitinq Tensile Strain at Bottom of the
Asphaltic Concrete versus Repetitions of
an lA,OOO-pound Axleloan.
-
z
·t
ow~
tnb
~g;~WT
r---------~~---
~-0
tnza:
--
LIJ...J
--'0~
-No
tr>N-
ZO
~
LIJ 0..
'
=) o•
t
1o•1'o•
I'o'
!'o•
1'o'
18-KIP EQUIVALENT AXLELOAO
Pigure 7.
Limiting ~ensile Strain at Rottom of the
Pozzolanic Rase versus Repetitions o~
an lR,OOO-pound Axleload.
'\'
0
LIJ
>LIJ
-o
tna:
"'~
LIJt!>
~a:>
0.. =>.
::L
0 "' 0'
wzo
--'
a:z
w-a:
375
550
720
~~
~~
LIJV'l
>
'I'
~~----r--r~-.~~.---~--,-,-~-r~
1o•
Figure R.
1o•
THICKNESS OF POZZOLANIC
BASE, INCHES
1o•
Vertical Compressive Strain at ~op of Suhgrade
versus Thickness of Pozzolanic Rase for Constant
Modulus of Elasticity of Pozzolanic Base and
Constant Thickness of .1\sphal tic Concrete
Surfacing.
':'
0
-
li..J
0
a:
a:
t!>
ID
=>
en
LL-•
-
ob
0...
0
.....
.....
a:
X:
375
0
550
a:
3:
720
'I'
~4-----r--r-r~rT~r----r--~~rT,~
I O'
Fioure q.
I O'
THICKNESS OF POZZOLANIC
BASE, INCHES
I 02
Hark at Top of Subgrane versus Thickness of
Pozzolanic ~ase for Constant Modulus of
Elasticity of Pozzolanic Rase ann Constant
Thickness of Asphaltic Concrete Surfacing.
LL0
>-en
1--0...
u
•
-w
l-en
en a:
a:ID~
...J
0
wu-
LL-Z
oa:
...J
eno
=:>N
3 INCHES RC
4 INCHES RC
...JN
5 INCHES RC
=:>O
00...
0
:t:
7 INCHES RC
~
~4---~--r-~~rn.----r~~-r~~
I~
10 1
I~
THICKNESS OF POZZOLANJC
BASE, INCHES
Figure 10. Equivalent Thickness Designs Tlsinq Pozzolanic
Base for Varying Thicknesses of Asphaltic
Concrete ann Moduli of Pozzolanic Rase
~laterials.
TABLE 1.
SPECIFICATIONS FOR
DENSE-GRADED AGGREGATE
BASES AND GRAVEL BASES
IN KENTUCKY (13)
==================================
PERCENTAGE FINER
(BY WEIGHT)
SIEVE
SIZE
(SQUARE
OPENING)
2"
1"
3/4"
3/8"
No. 4
No. 10
No. 40
No. 100
No. 200
DENSEGRADED
AGGREGATE
GRAVEL
AGGREGATE
100
70
50
35
25
12
5
-
-
100
100
80
65
'00
30
12
Wear -- 40* loss (maximum)
Soundness (Five Cycles) -12% loss (maximum)
Friable Particles -1.0% (maximum)
Shale -- 2.0% (maximum)
25
6
5
--
65
30
20
W
B
W
2
B
B
-
~
~
-
-
~
_________________________
~
g
g
m
R
W
B
B
-
W
2
~
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
STRENGTH PARAMETERS FOR VARIOUS POZZOLANIC MIXTURES AND FOR VARIOUS CURH:G CONDITIONS
-
-
-
-
-
-
-
-
-
TABLE 2.
___________________ DWRRR--REE
MIXTURE COMPONENTS (percent)
-----------------------------.-------------------"
,_
LIME
DENSE·
nY
ASH
KILN
DUST
PRODUCT
LIME
SCRUBBER
SLUDGE
RIVER
SANO
GRADED
AGGREGATE
POND
ASH
OPTlMUN
MOISTURE
CONTENT
(pt'rcent)
MAXIMUM
'"
DtNSITY
(pcf)
MIXTURE
SOI.ffiCE
(o)
UNCONFINED
CUR INC CQflPRESS!Vt
CotlDITIOll STRENGTII
(psi)
(>l
MODULUS
"
ELASTICITY
(psi)
SPLITTI
TDISIL
STRENG
(psi)
"- -------------------- "---- -------"- ----------------- ------------------------------------------------------- --------------"
"
90
90
10
15
15
20
20
85
85
80
80
70
70
30
30
100
100
100
100
100
11.8
11.8
9. 5
9. 5
1]. 7
11.7
12.4
12.4
43.7
43.7
43.7
43.7
43.7
126.2
126.2
ll\3 .6
ll\3 .6
133.5
133.5
128.3
128. 3
71.6
71.6
71.6
71.6
71 . 6
llo. 1
7
No. 1
No. 7
No. 1
No. 7
!lo. 1
No. 7
llo. 3
No. 1
llo. 6
No. 7
No. 11
field
fielrl
field
field
field
field
field
fie 1rl
field
field
field
field
field
186
557
No.
309
670
264
560
211
393
71
98
166
130
14 ,l\53
83,836
24 '185
37,526
18,067
29,029
14 ,302
58' 306
9 ,564
II ,430
21 '369
10,814
21 ,007
155
--------------"- ---------------------------.------.---- .. ". "-------.----- ----------.--.--.---.-.".------------------ -----10
90
10.3
150.5
99
8,870
13
10
90
10.3
150.5
lob
llo.
826
,471
62
'"'
10
90
9.9
133.7
lob
153
4
7 '159
No.
77
-"--------
90
10
15
15
15
15
20
20
20
20
100
100
9. 9
85
85
85
85
80
80
80
80
133.7
151 .4
11.2
151.4
11.2
10.9
10.9
11.0
11.0
11.8
11.8
50.4
50.4
No.
No.
No.
No.
No.
No.
No.
No.
No.
No.
No.
No.
l9b
lob
l9b
lob
lob
loo
lob
lob
lob
lob
lob
130.6
130.6
132.9
132.8
124.9
124.9
65.2
286
160
646
189
196
617
168
254
107
207
26 '124
10 ,21!5
59' 187
7 '782
17 '700
1.">,512
55,834
10,080
17 '576
9 '508
14 '955
738
636
515
315
232
44,431
23,295
25,157
ll '589
6 ,377
1,192
87,545
74,445
62,980
216,524
166,618
202 ,027
96,608
259,895
275
10
7
68
6
12
12
9
9
65.2
---.----.---"---- -----------.--------------------------.------------------------.---- --------------------------12
88
6. 5
ll\2 .1
lob
646
35,038
No.
12
16
16
20
20
BB
84
84
80
80
6. 5
7.3
7 .3
6.8
6.8
142 .1
140.6
140' 6
135.8
135' 8
lob
lob
lob
lob
lob
5.6
5.6
134.3
134.3
7.4
7.4
7.4
7.4
139.6
139.6
field
field
cores
cores
lab
lab
139.6
lab
lab
7 .5
139.2
139.2
139.6
139 .6
146.3
133 .I
142 ,J
150.8
lob
lob
lob
lob
lob
leb
lob
lob
141.0
141.0
8
8
84
84
8
84
8
8
8
St.
8
8
84
84
84
St.
139.!1
llo.
No.
No.
No.
No.
No, 1
No.4
No. 9
No, 10
Nu. 1
No. 2
tlo. 4
No. 6
922
585
1,570
1,987
2,403
897
3,222
No. 1
1 ,291
No. 2
1 '526
226
387
-- ~------ ---------------.--.-.-.------" ~~-.-------- ---- ~ ~~.-----~ ~~: ~--- -- ~~~.- ------ ~~:- ~.--- --- ~~~---- --------------.--5
5
5
5
6
5
5
5
5
4
10
10
s
90
90
90
90
90
80
88
86
8
7. 5
7. 5
7. 5
6.4
8.0
6. 9
No. 4
228
No.
280
tlo.
488
No.
tlo.
No.
296
1 '116
94,669
1 so' 962
18,314
37,634
17,619
8.\
1' 290
----------------------------------------------------------------.-.--------------------------------------.-.-.
s
8
10
74
7. 5
141.0
lob
tlo. 1
1 '25)
""-
8
8
8
8
8
8
8
8
8
8
8
8
8
S
8
8
8
8
8
8
8
8
10
10
10
10
10
25
25
25
25
74
74
74
59
59
59
59
50
50
50
50
80
34
34
34
8
8
8
8
8
8
8
8
8
32
42
42
42
135 .(,
lob
leo
leb
lob
lob
lob
lob
lob
lob
7 .1
135.6
lJS. 6
leb
7.1
10.1
110.9
~
leb
leb
i~b---
6.6
137.5
135.1
lab
lab
133.6
133.6
\33.6
lab
lab
lab
1"- I .0
138.7
138.7
138.7
138. 7
7 .6
7 .1
135.6
7 .1
34
--s---·a-------------·-------- ·;:z------ t.i
8
7. 5
7.5
7. 5
7.6
7.6
7.6
(~j------
52(d)
84(e)
42(e)
42(e)
42(e)
---- ·;: o·----- i ;s i · · --8.0
7.2
7.2
7.2
---------------- .. "- ---------"-- ·-. --------.---------------.--"Lab"
refer~
to samples mixed from tlry components in the
llo. 2
No. 3
No. 4
No,
No.
No,
tlo.
1
2
3
4
No. 1
---· ·
82
123
923
157
No. 3
tlo. 4
105
tlo.
No.
Uo.
;~o.
tlo.
----
134
1)6
1,272
356
No. 2
No. 1
;~ ~---
"-
200
79
89
139
------ ;;:9------- ·149'~956---- ·-- ·
157
1,317
1,194
69
l\39
4,237
127,193
tab~~~~~;;:-~fi:~id~-~~f~~~-~~-;~~~i:~~-~i~;d-1~-~;;;·i:~~;:~~~;
a.
b.
~~~~n~o~~~~~~~~n!rorn a field situation, "cores" refers to saotples obtai.ned by corine an existing vavement.
c.
d.
e.
Clo. 1
7 days at 100 F in a sealed contRiner (ASTM C 593·79)
tlo. 2
7 days at 100 F in a sealed container and then 7 days at room temperature ln Air
No. 3
7 days at room temperature ln a sealed container
No. 4
14 <.lays at room ter~~perature in air
No. 5
21 days at room temperature in a :~ealed container
No, 6
28 days at 100 F in a sealed contnlner
No. 7
7 days at 100 F in a sealed container and then 21 days at room temperature in 11 tr
No, 8
28 days at room temperature in air
No. 9
49 days ambient curin~; (field con<lltions) followed by a 14 day soaking period
No. 10 -· 132 days ambient curing (field ccmditions) followed by a 14 day soaking perLod
No. 11 -- 62 days at room temperature in air
No. 11 aggregate substituted for dense-graded aggregate.
Aggreeate substituted for dense-graded aggregate consists of 32t No. 11, 20:t aggregate meal.
Hines screenings substituted for dense-graded nggregate.
TABLE 3.
ECONOMIC COMPARISONS FOR PAVEMENT DESIGNS UTILIZING POZZOLANIC MATERIALS
======================================================================================
MA'T''I<:RIALS
THICKNF.SS
f!NCHF.S)
PAVING
TJN!'I'
COST
AREA
(SO!JARF. YARDS)
'I'Ot>JNAGE*
($/'T'Ol'l)
ALTP.RNATF: A -- Conventional nesiqn -- 7" asphaltic concrete
14" nense-qraneo aqqreqate
nense-GraOeO
S7.55
.1\gqreqate
14
lfll,?3l
131' 4fi<)
Asphaltic Concrete
7.fJ.f'iQ
l7.Q,767.
Rase
4 1/?.
32,llh
2(),?'>
l2A,7t:;Q
10,623
Binner
1 1/?
l2R,3fl2
7,057
?4.31
Surf'ace
1
Total for Alternate
TOTAL
COST
(S I
4.1, 3R"i
::1?.,116
10,623
7,057
fih4,4A:?
22fl,41CJ
171,546
U,7!!:
~96,544
1.A~
243,q52
:?.0.1'i9
664,4R2
2?.:0,41Q
171, 154F.i
?.:0.7"i
~4.31
1,Fiq6,943
Total for Alternate
AL'l''!\RNA'l'F. C - - 5" asphaltic concrete
R" pnzzolanic base
Pozzolanic Rase
A
111, 4Fi9
l?.:Q,762
Crack Relief Layer
Asphaltic Concrete
12Q,7f>?.
Base
?: 1/?.:
12R,75Q
Rin<'ler
1/2
Surface
1
l?:A,302
57,84fi
17,84?.
1fl,fi23
7,057
13.75
7q5,3~7
1.88
243,QS2
2f).6Q
?.0.75
24.31
36Q,l'>7
?:20,41Q
171,546
l;FH10,4Fi1
'l'otal f'or Alternate
(s I
$7fi4, 295
l,R2n,74:?
AL'l'F.RN"A'l':P. R -- 7" asphaltic concrete
fi" pozzolanic base
131,46Q
Pozzolanic Rase
fi
1/.Q, 7f'i2
Crack Relief Layer
Asphaltic Concrete
12Q,76?
Base
4 1/2
1?.:R,75Q
1 1/7.
Rin<'ler
1?.A, 302
Surface
1
SAVINGS
n
(76,201)
?:0,2Rl
AL'l'F.RNA'l'E n --
:!" asphaltic concrete
10" poz7.olanic hase
Hl
131, 46Q
Pozzolanic Rase
Crack Relief Layer
Asphaltic ~oncrete
l?.:R,7t;Q
Ain<ier
1?.R,302
Surface
1
'
~otal
for Alternate
7'2,3011
1],7<;
1. RR
9Q4,?.14
?4:l,QS?.
14, 1F;3
7,057
:W.7'i
24.:n
2q3,RQ2
171. l:i4fi
1,1"iQ4,624
*Tonnaqes estimaterl on the basis of 110 pounOs per square yarrl per inch
12fi,11R
TABLE 4.
ROAD RATER DEFLECTIONS
ON 6-INCH POZZOLANIC
BASES
=================================
DEFLECTIONS
(inches x 10- 5 '
SENSOR Nm1BER
PROJECT
NUMBER
No. 1
No. 2
No. 3
1
53.R
2
3
llR. 5
29.R
46.0
56,Q
15.1
24.R
24.3
147.2