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Roller Compacted Concrete
and the
Ready Mix Industry
Frank Lennox
Manager of Technical Services
Member of ACI 327-Roller Compacted Concrete Committee
Sub-committee chairman ASTM C9.45 Roller Compacted Concrete
What ready mix experience does
the speaker have???
Question #1
I have studied a manual and
have had practical experience.
Up until 15 years ago, all
Roller Compacted
Concrete Pavement
material was produced
using a standard pug mill.
Is the mix design procedure
different for the ready mix
industry?
NO!You use the same procedures
as set forth by the industry!
Adjusted for Specific
gravity differencesAggregate Gradation Analysis
Percent Passing Sieve Combine
d (by
Volume)
Retaine
d on
Sieve
Retained
Requirem
entSand
#1
Sand
2A B C
Sieve
Size
(%) (%) (%)
10.1
%
40.7
%
24.6
%
24.6
% 0.0% 100.0
1.5" 100 100 100 100 100 100.0 0.0 0-4
1" 100 100 100 100 100 100.0 0.0 8-18
3/4" 100 100 95.2 100 100 98.8 1.2 8-18
1/2" 100 100 44.8 100 100 86.4 12.4 8-18
3/8" 100 100 26.8 99.1 99 81.8 4.6 8-18
4 95 99.8 4.2 32.4 32 59.2 22.6 8-18/ 4-8*
8 81.9 88.9 1.3 6.9 6 46.5 12.7 8-18/ 4-8*
16 74.9 52.2 0 2.1 2 29.3 17.1 8-18/ 4-8*
30 67.4 30 0 0 1 19.0 10.3 8-18
50 28.4 17.3 0 0 0.4 9.9 9.1 8-18
100 2.8 8.3 0 0 0 3.7 6.3 1.5-5.0
*Lower range
acceptable (for any
single sieve) if
aggregates are
0
10
20
30
40
50
60
70
80
90
100
11/2"
1" 3/4" 1/2" 3/8" 4 8 16 30 50 100 200
Perc
en
t P
assin
g
Sieve Size
Aggregate Gradation
Step 2: Select a cementitious
content range
A good starting point may be between
11 and 13 % for cement without the
addition of SCM’s
Step 3: Develop moisture-
density plots
For a fix cementitious %, different
moisture contents are selected using
ASTM D1557 modified Proctor.
OR YOU CAN DO WHAT
WE DID!
TAKE A STANDARD 4000
PSI MIX, REMOVE SOME
WATER, ADJUST THE
SAND QUANTITY AND
PRAY!
Cement 400 lbs
Fly Ash 100 lbs
#67 Stone 1800 lbs
Concrete Sand 1300 lbs.
Water 18 – 20 gals
FIRST MIX DESIGN
Material found at most ready mix concrete operations!
0
20
40
60
80
100
120
1" 3/4" 1/2" 3/8" #4 #8 #16 #30 #50 #100 #200
RCC Gradation Curve
Original Mix
Upper Lower Combined
NEW MIX DESIGN
2005
Cement 400 lbs.
Fly Ash 100 lbs.
Coarse Agg. #67 1100 lbs.
Coarse Agg. #89 or #7 ‘s 1100 lbs.
Fine Aggregate 1330 lbs.
Water 180 lbs.
Admixture Standard Water Reducer
0
20
40
60
80
100
120
1" 3/4" 1/2" 3/8" #4 #8 #16 #30 #50 #100 #200
RCC Gradation Curve 3 Aggagates
Sequatchie Concrete Products
Upper Lower Combined
Gradation curve for 3 aggregates
EVEN NEWER MIX DESIGN
2012
Cement 375 lbs.
Fly Ash 125 lbs.
Coarse Agg. #67 850 lbs.
Coarse Agg. #89 or #7 ‘s 850 lbs.
Fine Aggregate - Mfg. 1415 lbs.
Fine Aggregate – Natural 350 lbs.
Water 180 lbs.
Admixture Standard Water Reducer
0
20
40
60
80
100
120
1" 3/4" 1/2" 3/8" #4 #8 #16 #30 #50 #100 #200
RCC Gradation Curve 4 Aggregates
Sequatchie Concrete Products
Upper Lower Combined
Gradation curve for 4 aggregates.
Adjusted for Specific
gravity differencesAggregate Gradation Analysis
Percent Passing Sieve Combine
d (by
Volume)
Retaine
d on
Sieve
Retained
Requirem
entSand
#1
Sand
2A B C
Sieve
Size
(%) (%) (%)
10.1
%
40.7
%
24.6
%
24.6
% 0.0% 100.0
1.5" 100 100 100 100 100 100.0 0.0 0-4
1" 100 100 100 100 100 100.0 0.0 8-18
3/4" 100 100 95.2 100 100 98.8 1.2 8-18
1/2" 100 100 44.8 100 100 86.4 12.4 8-18
3/8" 100 100 26.8 99.1 99 81.8 4.6 8-18
4 95 99.8 4.2 32.4 32 59.2 22.6 8-18/ 4-8*
8 81.9 88.9 1.3 6.9 6 46.5 12.7 8-18/ 4-8*
16 74.9 52.2 0 2.1 2 29.3 17.1 8-18/ 4-8*
30 67.4 30 0 0 1 19.0 10.3 8-18
50 28.4 17.3 0 0 0.4 9.9 9.1 8-18
100 2.8 8.3 0 0 0 3.7 6.3 1.5-5.0
*Lower range
acceptable (for any
single sieve) if
aggregates are
0
10
20
30
40
50
60
70
80
90
100
11/2"
1" 3/4" 1/2" 3/8" 4 8 16 30 50 100 200
Perc
en
t P
assin
g
Sieve Size
Aggregate Gradation
C 1040 In-Place density Nuclear Methods
C 1170 Consistency & Density Vibrating Table
C 1176 Cylinder Molds – Vibrating Table
C 1435 Cylinder Molds – Vibrating Hammer
ASTM Test Procedures for RCC
ASTM update for Roller Compacted
Concrete
Test Method for molding beams
Reason: A method for determining the
flexural strength of RCC mix design used
in pavements
Equipment: ASTM C 1435 vibrating
hammer with a square tamping plate,
rectangular steel beam molds as used in
ASTM C 31, and testing as per ASTM C
78.
ASTM update for Roller Compacted
Concrete
Test Method for Density and Air Content
Reason: There have been signs of freeze-
thaw damage to some RCC dams in
higher elevation.
Equipment: Standard pressure air meter
ASTM C 231 and standard vibrating
hammer as in C 1435.
ASTM update for Roller Compacted
Concrete
Test Method for preparation compaction
and density using Gyratory compactor.
Reason: To find a way to establish a
consistent method for producing RCC
specimens using gyratory compacting
technology.
Equipment: Gyratory Compactor as per
D 6925