Concrete Mixture Designs for
O’Hare Modernization Plan
University of Illinois (Urbana-Champaign)
Department of Civil and
Environmental Engineering
Chicago O’Hare
January 12, 2006
Project Goal
Investigate cost-effective concrete properties and
pavement design features required to achieve longterm rigid pavement performance at Chicago
O’Hare International.
Project Team
Principal Investigators
Prof. Jeff Roesler
Prof. David Lange
Students
Cristian Gaedicke
Sal Villalobos
Zach Grasley
Rob Rodden
Project Objectives
Develop concrete material constituents and
proportions for airfield concrete mixes
Strength
volume stability
fracture properties
Develop / improve models to predict concrete
material behavior
Crack width and shrinkage
Evaluate material properties and structural design
interactions
joint type & joint spacing (curling and load transfer)
Saw-cut timing
Project Objectives
Material
constituents and
mix design
Laboratory tests
Test for material
properties
Analysis of existing
concrete mix designs
Concrete properties
Modeling
Optimal joint types
and spacing.
Long-term
performance at
ORD
FY2005 Accomplishments
Tech Notes (TN) -
www.cee.uiuc.edu/research/ceat
TN2: PCC Mix Design
TN3: Fiber Reinforced Concrete for Airfield Rigid
Pavements
TN4: Feasibility of Shrinkage Reducing Admixtures for
Concrete Runway Pavements
TN11: Measurement of Water Content in Fresh
Concrete Using the Microwave Method
TN12: Guiding Principles for the Optimization of the
OMP PCC Mix Design
TN15: Evaluation, testing and comparison between
crushed manufactured sand and natural sand
TN16: Concrete Mix Design Specification Evaluation
TN17: PCC Mix Design Phase 1
TN2: PCC Mix Design
Mix Id.
Water
Type I Cement
Type C Fly Ash
Coarse aggregate (# 57
Limestone, 1" max size. )
Fine aggregate
Steel Fibers
Air entrainment admixture
(Excel Air)
Water Reducer (Excel Redi
Set)
Properties
W/CM
fr7
fr28
Air
Slump
Proposed
Mix #1905
(2000)
280
541
135
Revised
Mix #1905
(2000)
262
588
100
Proposed
Mix #1933
Mix #1994
(2000)
(2000)
280
262
588
588
100
130
Mix K-5
003Units
00(2004)
258
lb/yd3
541
lb/yd3
135
lb/yd3
1850
1850
1850
1800
1840
lb/yd3
1125
0
1103
0
1115
0
1100
85
1117
0
lb/yd3
lb/yd3
N/A
7
N/A
N/A
6.8
oz/yd3
29
15
28
29
30.4
oz/yd3
Proposed
Mix #1905
0.41
N/A
N/A
5-8
2
Revised
Mix #1905
0.38
788
1030
5-8
3 +/- 1
Proposed
Mix #1933 Mix #1904
0.41
0.36
802
N/A
842
N/A
5-7
5-8
3 +/- 1
3 +/- 1
Mix K-5
003-00
0.38
770
855
6.2
1
Units
psi
psi
%
in
Survey of Existing Mixes
Airport
Capital
Airport
St. louis
Lambert
St. louis
Lambert
Mix Id.
N/A
Mix 1 F
Mix 4 F
Water
Cement
Type C Fly Ash
GGBS
Coarse aggregate #1
Coarse aggregate #2
Fine aggregate
Fibers
Air entrainment admixture
Water Reducer
233
490
150
1842
1156
N/A
19.6
250
510
80
1866
1225
5.6
14.2
258
535
80
1834
1220
5.6
14.2
St. louis
Lambert
Mix 4 F
w/ fibers
258
535
80
1834
1220
3
5.6
14.2
I
I
I
I
Materials Properties
Cement Type
Coarse aggregate # 1 max.
size. (in)
Coarse aggregate # 2 max.
size. (in)
Fine aggregate type
AEA type
WR type
Fiber type
Concrete Properties
W/CM
fr28
Air
Slump
N/A
-
3/4" (#67) 3/4" (#67)
-
River
Sand
Polychen
AEA Grace
AE VRC
Daracem
Polychen
Grace
MC 400
N/A
-
-
-
-
0.36
770
5.5
4 1/2"
0.42
1033
7.6
2"
0.42
850
7
3 3/4 "
Mix 3 F
Mix 5 F
248
354
88
148
1872
1228
3
17.7
258
310
93
217
1808
1232
3.1
18.6
St. louis
Lambert
Mix 5 F
w/fibers
258
310
93
217
1808
1232
3
3.1
18.6
I
I
I
St. louis
Lambert
St. louis
Lambert
Fort Californ Califor
Wayne
ia
nia
Mix 6 F
Mix P 5
Mix 1
Mix 1
Mix 2
258
372
93
155
1836
1206
3.1
18.6
250
680
1790
1280
N/A
N/A
218
288
192
1424
615
1198
N/A
N/A
300
489
122
1570
400
1165
N/A
N/A
258
479
85
1400
475
1310
1.7
16.92
I
I
I
I
II
1" (57)
1" (57)
3/4" (#67) 3/4" (#67) 3/4" (#67) 3/4" (#67) 3/4" (#67) 3/4" (#67) 1" (57)
-
River Sand River Sand
Polychen
AE VRC
Polychen
MC 400
St. louis St. louis
Lambert Lambert
Polychen
AE VRC
Polychen
MC 400
GRT
Polymesh
fibers
0.42
905
7
3 3/4 "
-
-
-
River
Sand
Polychen
AE VRC
Polychen
MC 400
River
Sand
Polychen
AE VRC
Polychen
MC 400
-
-
River
Sand
Polychen
AE VRC
Polychen
MC 400
GRT
Polymesh
fibers
0.42
700
5
1 1/4 "
0.42
675
5
3"
0.42
675
5
3"
-
-
River
River
Sand
Sand
Polychen
GRT AEA
AE VRC
Polychen GRT KB
MC 400 1000
lb/yd3
lb/yd3
lb/yd3
lb/yd3
lb/yd3
lb/yd3
lb/yd3
lb/yd3
oz/yd3
oz/yd3
1/2 x
#4"
N/A,FM N/A,FM Sechelt
= 2.68 = 2.96 Sand
3/8"
3/8"
N/A
N/A
MBAE
N/A
N/A
Pozz
200N
-
-
-
-
-
0.42
675
5
3"
0.37
1280
6
1 1/2"
0.45
N/A
N/A
N/A
0.49
N/A
N/A
N/A
0.46
767
3
3 1/4"
Units
psi
%
in
Tech Note 3
Fiber Reinforced Concrete for Airfield
Rigid Pavements
225
Plain
0.48% Synthetic Macro Fiber
200
0.32% Synthetic Macro Fiber
175
Load (kN)
150
125
100
75
50
25
0
0
1
2
3
4
5
6
7
8
9
10
11
12
Average Interior Maximum Surface Deflection (mm)
 Final cost: reduction of 6% to an increase of 11%
13
Tech Note 4
Feasibility of Shrinkage Reducing Admixtures
for Concrete Runway Pavements
Reduced Shrinkage and Cracking Potential ~ 50% reduction
Cost limitations (?)
Figure 1. Unrestrained shrinkage of mortar bars, w/c = 0.5 (Brooks et al. 2000)
Tech Note 11
Measurement of Water Content in Fresh
Concrete Using the Microwave Method
Strengths: quick, simple, and inexpensive
Limitations: need accurate information on
 cement content
 aggregate moisture and absorption capacity
TN 12: Guiding Principles for the
Optimization of the OMP PCC Mix Design
1st order:
Strength, workability
2nd Order:
Shrinkage, fracture properties
LTE & strength gain
Tech Note 15
Evaluation, testing and comparison between
crushed manufactured sand and natural sand
Gradation According to ASTM C-33
100
Manufactured Sand(ms)
Natural Sand(ns)
ASTM Fine
ASTM Coarse
80
PERCENTAGE PASSING.
Gradation
physical properties
Finness Modulus
ms = 3.12
ns = 2.64
60
40
20
0
200
100
50
30
16
8
4
0.375
ASTM SIEVE NUMBER
ASTM C-128
ASTM C-29
Material
BSG(ssd)
BSG(dry)
AC(%)
Manufactured sand
Natural sand
2.7
2.43
2.63
2.38
2.59
2.15
Bulk density Bulk density
dry(kg/m3) ssd(kg/m3)
1628
1703
1670
1740
% Voids
38.1
28.3
Manufactured vs Natural Sand
Visual evaluation
4mm
Material retained in
the #8 sieve shows
difference in the
particle shape
500mm
4mm
500mm
Sieve No. 8
Sieve No. 50
The Manufactured
sand shows a rough
surface and sharp
edges due to the
crushing action to
which it was
subjected.
Tech Note 16
Concrete Mix Design Specification
Evaluation
Preliminary P-501 evaluation
Strength, shrinkage, and material constituent
contents
P-501 Guidelines
Our View
max w/cm = 0.50
Ok
3
Min cement content = 500 lb/yd
This could be lower
min flexural strength = 600 psi @ 28 d 700 ok, could be 90 d
fly ash content range = 10-20%
Ok
fly ash + slag range = 25-55%
Ok
max slag when temp < 55 F = 30%
Ok
air content = 5.5% for 1.5" topsize CA
Ok
air content = 6.0% for 0.75" topsize CA
Ok
2005 Accomplishments
Specification Assistance
On-site meetings at OMP headquarters
Brown bag seminars
Continued specification assistance (2006):
 Material constituents (aggregate type and size, SCM, etc.)
 Modulus of rupture and fracture properties of concrete
 Shrinkage (cement content, w/c ratio limits,etc.)
 Saw-cut timing, spacing and depth
 Pavement design
PCC Mix Evaluation – Phase II
Effect of aggregate size (0.75” vs. 1.5”)
Effect of 1.5” coarse aggregate:
Total cementitious content:
 688 lb/yd3, 571 lb/yd3, 555 lb/yd3 and 535 lb/yd3
Water / cementitious ratio:
 0.38 versus 0.44
Fly Ash / cementitious ratio:
 14.5% versus 0%
Effect of coarse aggregate cleaniness
PCC Mix Evaluation – Phase II
Testing
Fresh concrete properties
 Slump, Air Content, Unit Weight
Mechanical Testing
 Compressive strength (fc) at 7 and 28 days
 Modulus of Elasticity (E) at 7 and 28 days
 Split tensile strength (fsp) at 7 and 28 days
 Modulus of Rupture (MOR) at 7 and 28 days
Volume Stability Testing
 Drying and Autogenous Shrinkage trends for 28+ days
Fracture tests
 Early-ages (<48 hrs)
 Mature age (28 days)
Mixture design nomenclature
9 mixes were prepared:
555.44 – 555.44 st – 688.38 – 688.38 st
AAA.BB **
Cementitious
content (17%FA)
lbs/cy
**max aggregate size
w/cm
st = 0.75”
Otherwise 1.5”
Phase II Mix Design Results
ID
water (lb/yd3)
cement (lb/yd3)
fly ash (lb/yd3)
CA (lb/yd3)
FA (lb/yd3)
AEA (oz/yd3)
w/cm
CA/ FA
cm
w/c
Fl\y Ash/ CM
688.38 (1.5" 688.38
CA) CLEAN standard
688.44
688.38
571.44
571.38 571.44 Nof 535.44
555.44
AGG
(3/4 " CA) (1.5" CA) (1.5" CA) (1.5" CA) (1.5" CA) (1.5" CA) (1.5" CA) (1.5" CA)
261
262
303
261
251
217
251
235
244
588
588
588
588
488
488
571
535
455
100
100
100
100
83
83
0
0
100
1842
1850
1772
1842
1924
1982
1938
1984
1942
1083
1103
1042
1083
1132
1166
1140
1167
1142
19.4
12.7
19.4
19.4
16.1
16.1
16.1
15.1
15.6
0.38
0.38
0.44
0.38
0.44
0.38
0.44
0.44
0.44
1.7
1.68
1.7
1.7
1.7
1.7
1.7
1.7
1.7
688
688
688
688
570.96
570.96
571
535
555
0.44
0.45
0.51
0.44
0.51
0.44
0.44
0.44
0.54
0.15
0.15
0.15
0.15
0.15
0.15
0.00
0.00
0.18
Slump (in)
Air (%)
6.13
7.0
7.63
6.5
9.00
6.0
6.25
8.0
7.38
2.9
2.50
7.3
2.25
6.5
8.63
2.9
7.88
3.7
Density (pcf)
143.8
145.1
141.8
141.8
150.4
143.9
146.2
150.9
150.2
fs7 (psi)
362
526
275
440
412
416
505
390
480
570
423
454
513
429
524
415
490
4,045
3,267
3,241
3,608
3,369
3,329
2,338
3,327
4,217
4,131
3,785
4,344
3,744
5,366
3,369
4,212
3,476
4,177
4,031
3,879
4,224
3,326
3,426
3,692
#¡DIV/0!
3,752
3,695
3,438
4,204
3,881
3,958
3,311
4,209
#¡DIV/0!
802
668
639
688
651
794
619
663
fs28 (psi)
fc7 (psi)
fc28 (psi)
Ec7 (psi)
Ec28 (psi)
MOR28 (psi)
#¡DIV/0!
3,393
#¡DIV/0!
3,236
Strength Summary
Mixture ID
Coarse Aggregate Size (in)
Coarse Aggregate (lb/yd3)
Fine Aggregate (lb/yd3)
Water (lb/yd3)
Cement (lb/yd3)
Fly ash (lb/yd3)
Air (oz/yd3)
Slump (in.)
Air Content (%)
Unit Weight (lb/ft3)
Mixture ID
fsp28 (psi)
MOR28 (psi)
E28 (ksi)
688.38ST
0.75
1850
1103
262
588
100
12.7
7.5
6.5
145.1
688.38ST
570
802
3,752
688.38
1.5
1842
1083
261
588
100
19.4
6.25
8
141.8
688.38
454
639
3,438
571.44
1.5
1938
1140
251
571
0
16.1
2.25
6.5
146.2
555.44
1.5
1942
1142
244
455
100
15.6
8.0
3.7
150.2
571.44
524
794
3,958
555.44
490
663
4,209
Shrinkage Results Phase II
Total and Autogenous shrinkage
Experimental Shrinkage Data for all Mixes
0.6
0.5
688.38ST Total
688.44 Total
688.44 Autog.
688.38 Total
688.38 Autog.
571.44 Total
571.38 Total
571.38 Autog.
571.44 NF Total
535.44 Total
555.44 Total
Shrinkage (mm/m)
0.4
0.3
0.2
0.1
0
0
5
10
15
-0.1
Age of Concrete (days)
20
25
Drying Shrinkage – Phase II
Total Shrinkage vs. Age
Shrinkage (microstrain)..
500
400
300
\
200
688.38 st
688.38
100
571.44
555.44
0
0
5
10
15
20
25
30
Concrete Age (days)
Mixture ID
sh3 (microstrain)
sh7 (microstrain)
sh14 (microstrain)
sh28 (microstrain)
688.38 st
688.38
571.44
555.44
48
193
292
417
118
233
338
405
139
250
320
380
52
158
273
335
Fracture Energy – Phase II
GF = cracking resistance of material
GF = joint surface roughness indicator
Load vs Displacement
4000
Peak
Load
3500
3000
Load (N)
2500
2000
1500
1000
500
0
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
CMOD (mm)
GF = Area under the Curve
Cracking Area
0.8
0.9
1
WST Test
The WST Specimen
80mm
30mm
Notch detail
40mm 80mm
57mm
2mm
200 mm
b
t
a
205mm
200 mm
a = a/b
Testing Plan – 4 Mixtures
Wedge splitting specimens (7)
6, 8, 10, 12 and 24 hours
7 and 28 days
Cylinders for compression and split tensile
strength for 1,7 and 28 days and E values for 7
and 28 days
MOR for 28 days
Fracture Plots of PCC mixtures
688.38st
555.44st
2500
2000
6hrs
8hrs
10hrs
12 hrs
1 day
7 day
Force(N)
1000
1500
1000
500
500
0
0
0
0.2
0.4
0.6
0.8
0
1
0.2
0.4
0.6
0.8
1
COD(mm)
COD(mm)
688.38
555.44
2500
2500
8 hrs
10 hrs
12 hrs
24 hrs
7days
28 days
1500
1000
6hrs
8hrs
10hrs
12hrs
1 day
7 day
28 day
2000
FORCE(N)
2000
FORCE(N)
FORCE(N)
1500
6hrs
8 hrs
10 hrs
12 hrs
1 day
7 day
28 day
2000
1500
1000
500
500
0
0
0
0.2
0.4
0.6
COD(mm)
0.8
1
0
0.2
0.4
0.6
COD(mm)
0.8
1
Fracture Energy Results-Phase II
Age = 28-days
Load vs. CMOD curves for Wedge Splitting Samples
3000
688.38st
688.38
2500
555.44
Fv (N)
2000
1500
1000
500
0
0
0.5
1
1.5
CMOD(mm)
Mixture ID
GF (Nm)
688.38 st
156
688.38
166
571.44
N/A
555.44
161
2
Concrete Brittleness
Characteristic Length
Mixture ID
fsp28 (psi)
E28 (ksi)
GF (Nm) @ 28-day
lch (in)
688.38ST
570
3,752
156
10.3
EGF
lch 
2
fsp
688.38
454
3,438
166
15.8
571.44
524
3,958
N/A
N/A
555.44
490
4,209
161
16.1
Less brittle mixes
w/ larger MSA
GF vs Joint Performance
Chupanit & Roesler (2005)
Fracture Energy  Shear Stiffness
 Joint Performance
*need crack width!
Mixture ID
MOR28 (psi)
GF (Nm) @ 1-day
GF (Nm) @ 28-day
688.38ST
802
111
156
688.38
639
155
166
571.44
794
N/A
N/A
555.44
663
126
161
PCC Mix Design – Phase II
Summary*
Larger aggregates reduce strength by 20%
28-day GF similar  similar cracking resistance
Larger aggregates reduce concrete brittleness
1-day fracture energy  with larger MSA
 greater joint stiffness / performance
No significant shrinkage difference
TNXX – February 2006
*Roesler, J., Gaedicke, C., Lange, Villalobos, S., Rodden, R., and Grasley, Z. (2006),
“Mechanical Properties of Concrete Pavement Mixtures with Larger Size Coarse
Aggregate,” accepted for publication in ASCE 2006 Airfield and Highway Pavement
Conference, Atlanta, GA.
Saw-cut timing and depth
Stress analysis of slab (temp & shrink)
Size Effect (fracture) Model
Concrete Material Fracture Parameters
Wedge Splitting Test @ early ages
No method to obtain Critical Stress Intensity
Factor (KIC) and Critical Crack Tip Opening
Displacement (CTOCC) for WST
FEM MODEL FOR THE WST SPECIMEN
Saw-cut timing and depth
Fracture Parameters
WST specimen
80mm
40mm 80mm
Notch detail
30mm
200 mm
57mm
2mm
a
200 mm
b
t
205mm
a = a/b
Saw-cut timing and depth
FEM Model
200 mm
Special Mesh
around crack
tip
Q8 elements
Symmetry and
BC considerations
100 mm
Saw-cut timing and depth
FEM Model
Stress around crack tip
Calculation of KI
Quarter
point
nodes
FEM ANALISYS
FEM MODELING OF THE WST
K IC
Psmax = peak splitting load
KIC = critical SIF
P
 smax1/2 * f1 (a )
t *b
CTOD  f 3 (a ) * CMOD
CMOD 
Psp
t *E
* f 2 (a )
CTODc= critical CTOD
cf 
  CTODC * E 

32 
K IC


2
CMODc= critical CMOD
f1(a) = geometrical factor 1
f2(a) = geometrical factor 2
f3(a) = geometrical factor 3
E = modulus of elasticity
Gf = initial fracture energy
2
K IC
Gf 
E
Evolution of GF vs Age
Fracture energy Vs Age
1.5” max aggregate size
175
555.44
555.44st
688.38
688.38st
150
Gf(N-m)
125
100
75
50
25
0
0
5
10
15
20
25
Age(hours)
Fracture energy Vs Age
200
180
555.44
555.44st
688.38
688.38st
160
Gf(N-m)
140
120
Large increase in GF between 8 and
24 hrs (saw-cutting operations).
100
80
60
40
20
0
1
10
100
Age(hrs)
1000
Saw-Cut Timing Model
Concrete E and fracture properties(cf ,KIC) at early ages.
Using Bazant’s Size Effect Model to analyze finite size slabs.
Develop curves of nominal strength vs notch depth for timing.
Nominal strength vs ao/d for the 300mm slab
1.20
ls@6hr
Nominal strength
1.00
ls@12hr
rg@6hr
0.80
rg@12hr
0.60
0.40
0.20
0.00
0.000
0.100
0.200
0.300
ao/d
•After Soares (1997)
0.400
0.500
0.600
Joint Type Analysis
How can we rationally choose dowel vs.
aggregate interlock joint type & joint
spacing?
Need to predict crack width & LTE
Shrinkage, zero-stress temperature, creep
Aggregate size and type (GF)
Slab length & base friction
Reduced aggregate interlock with
small max. size CA
Dowels deemed necessary
Crack width, w
Larger max. size CA
Larger aggregate top size increases aggregate
interlock and improves load transfer
Crack width, w
Crack Width Model Approach
Step 1: Predict
crack opening, w
Step 2: Predict
differential
deflection, δdiff
Step 3:
Determine
LTE
Step 4:
Acceptable
LTE?
Inputs:
RH, T, L, E, , C
Inputs:
w, CA topsize, 
Inputs:
δfree, δdiff, 
Inputs:
FAA
recommendation
c2i f i 


CWi  CC  L    SHRi  a PCC T 


E
PCC
i


*after DG2002
Crack spacing
Drying shrinkage
Temperature drop
Restraints
f
i

L U m  P
 2  L
 C 0 1    f
c1i  d b
h  2

Base friction
Curling (thermal and moisture)
Steel reinforcement
Step 1: Predicting crack width
opening, w
Average
increase
with age
due to
shrinkage
Future Joint Analysis Questions
What is an acceptable LTE?
What is LTE when dowels are removed?
Can joint spacing be increase from 18.75 to 25 ft?
How much can LTE be changed by concrete
property changes?
Project Tasks and Progress
Literature Review
Survey of existing mix designs
Review of mix design strategies
Volume Stability Tests
Drying and Autogenous shrinkage
Optimization of concrete mixes to
reduce volumetric changes
Strength Testing
Modulus of rupture, splitting and
compressive strength
Fracture energy and fracture surface
roughness
Status
Done,
TN2, 3, 4, 15
Done, TN 12
Done
Done,
TN 12 and TN 17.
Done, TN 12,
TN 17, conf.
paper
Fracture Tests
Done
Project Tasks and Progress
Joint Type Design
Slab size and jointing plans:
productivity, cost, performance.
Optimization of concrete
aggregate interlock to ensure
shear transfer.
Joint (crack) width prediction
model for concrete materials.
In progress, TN 3.
Analysis pending,
fracture and
shrinkage tests
done.
In progress,
TN 12.
Fracture tests
In progress
Project Tasks and Progress
Saw-cut timing and depth
Saw-cut timing criteria for
the expected materials
Analytical model / Validation
FEM model
developed to obtain
fracture results from
WST samples,
currently applying
results to determine
saw-cut timing and
depth.
Fiber Reinforced Concrete
Materials
Overview of structural fibers
for rigid pavement
Literature
Review done,
TN 3.
New Work for FY2006
Functionally-layered concrete pavements
Multi-functional rigid pavement
Cost saving
GREEN-CRETE
Recycled concrete aggregate
Effect of recycled aggregate on mechanical and
volumetric properties of concrete
Current work:
Recycled Concrete as Aggregates (RCA)
for new Concrete
Recycled Concrete Aggregate
Use of RCA for OMP
RCA may lead to cost savings
Disposal costs
Trucking costs
Natural aggregate costs
RCA may increase shrinkage?
RCA less stiff than natural aggregate
RCA can shrink more than natural aggregate
Shrinkage may be same or reduced if RCA is
presoaked to provide internal curing
UIUC First Trial
RCA from Champaign recycling plant
Concrete came from pavements, parking garages, etc.
Mix of materials with unknown properties
Material washed, dried, and sieved to match natural
fine aggregate
Soaked for 24 hrs, surface dried, and then 100%
replacement of natural fine aggregate
Saturated RCA vs Lab Aggregates
20
Shrinkage strain x 10-6
0
lab stock
lab ssd
RCA SSD
-20
-40
-60
-80
-100
0
5
10
Age (d)
•Similar autogenous shrinkage curves
15
20
RCA Summary to Date
Optimization of RCA gradation may lead to
reduction in overall shrinkage
Other concerns:
Reduced concrete strength and modulus
Potential for ASR from RCA?
Source of chlorides to cause corrosion of dowels?
Future work - use RCA with known properties
Try different gradations
Measure strength/fracture properties also
Functionally Layered
Concrete Pavement
T, RH
P
Functions
Wear Resistant
E(z), υ(z), α(z), k(z), ρ(z), D(z)
h
Shrinkage Resistant
Fatigue Resistant
z
Support Layers
h1, E1, υ1, α1, k1, ρ1, D1
No fibers
h2, E2, υ2, α2, k2, ρ2, D2
fB = 0.1%
h3, E3, υ3, α3, k3, ρ3, D3
fA = 0.25%
Porous Concrete Friction/Noise Layer
Shrinkage Resistant Layer
Fatigue Resistant Layers
h4, E4, υ4, α4, k4, ρ4, D4
fA = 0.5%
Support Layers
Functionally Layered
Concrete Pavement
Experimental Program:
P
(a)
Top layer
(b)
h1
h
Bottom layer
Top layer
h2
ao
CMOD
Bottom layer
Configuration ID
PCC/PCC
PCC/FRCPP
FRCPP/PCC
FRCPP/FRCPP
Top layer (h1)
Bottom layer (h2)
Type of specimen
# of specimens
PCC
PCC
TPB WST
3/3
2
PCC
FRCPP
TPB WST
3
2
FRCPP
PCC
TPB WST
3
2
FRCPP
FRCPP
TPB WST
3
2
PCC / FRCCS
FRCCS / PCC
PCC
FRCPP
FRCPP PCC
TPB
TPB
3
3
FRCCS /
FRCCS
FRCPP
FRCPP
TPB
3
Functionally Layered
Concrete Pavement
Structural Synthetic Fibers in Beams
P
Top layer
h1
h
Bottom layer
ao
CMOD
h2
Functionally Layered
Concrete Pavement
Steel Fibers in Beams
P
Top layer
h1
h
Bottom layer
ao
CMOD
h2
Functionally Layered
Concrete Pavement
Synthetic Fibers in WST Specimen
Project Tasks and Progress
Recycled Concrete Aggregate
(RCA)
Review of previous experiences
with RCA
Experimental program, and test
to determine effect of RCA on
relevant mix properties
In progress
In progress
Project Tasks and Progress
Functionally Layered Concrete
Pavement
Overview of structural fibers for
rigid pavement
Layered pavement systemspreliminary study
Fracture resistance of two layer
concrete pavement systems
Literature
Review done,
TN 3.
Done,
preliminary
results show
potential
In progress
2006 First Quarter Deliverables
TN - Phase II concrete mix evaluation
Large aggregate mixtures paper (ASCE)
TN – Fracture Properties of Concrete
Mixtures (WST)
Saw-cut timing and depth
FEM Model
Determination of Fracture parameters
K IC  Psmax *
f1 (a )
t * b1/2
K IC 
f1 vs a/b
5.0
4.5
Psmax
* f1 (a )
t * b1/2
y = 9.8214x - 1.4584
R2 = 0.9779
f1
4.0
3.5
y = 25.598x 2 - 15.757x + 4.8066
R2 = 0.9996
3.0
2.5
2.0
0.40
0.42
0.44
0.46
0.48
0.50
a/w
0.52
0.54
0.56
0.58
0.60
Saw-cut timing and depth
FEM Model
Determination of Fracture parameters
CMOD  Psp *
f 2 (a )
CMOD 
t *E
Psp
t *E
* f 2 (a )
CTOD  f 3 (a ) * CMOD
f2 vs a/b
80.0
y = 207.07x - 58.121
R2 = 0.9736
0.35
60.0
0.3
50.0
0.25
f3
f2
70.0
40.0
30.0
y = 1.2088x - 0.3456
R2 = 0.9847
0.2
y = -3.3883x 2 + 4.7542x - 1.2625
R2 = 0.9991
0.15
20.0
y = 590.13x 2 - 382.59x + 86.31
R2 = 0.9995
0.1
10.0
0.0
0.40
f3 vs a/b
0.4
0.05
0.42
0.44
0.46
0.48
0.50
a/w
0.52
0.54
0.56
0.58
0.60
0
0.40
0.42
0.44
0.46
0.48
0.50
a/w
0.52
0.54
0.56
0.58
0.60
Recycled Concrete Aggregate
Some findings from literature
When used with a very low w/cm, RCAC
compressive strength can exceed 9000psi at 28 d
Autogenous shrinkage can be lowered by 60% by
adding saturated RCA
While there are no reports in the literature, it is likely that RCA
increases tensile creep, which would reduce propensity for
shrinkage cracking or curling
I. Maruyama, R. Sato, “A trial of reducing autogenous shrinkage by recycled aggregate”, in Proceedings
of self-desiccation and its importance in concrete technology, Gaithersburg, MD, June 2005.