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Recent Advances in the Design &
Construction of Roller Compacted
Concrete Pavements
Center for Environmentally Sustainable
Transportation in Cold Climates
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AGENDA
• Roller Compacted Concrete
• What is it? Where has it Been Used? and Why?
• Pavement Design
• RCC Construction Process
• Recent Advances / Changes
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ROLLER COMPACTED CONCRETE IS A ZERO SLUMP CONCRETE
With A Long History Of Good Performance On Heavy Duty Pavements
• Concrete Pavement, Placed more efficiently
• No Slump, low water content
• Consistency of cement treated base
• Placed by asphalt pavers
• Compacted with vibratory rollers
• No forms
• No reinforcing steel
• No finishing
• Normal concrete strength
• Low W/C ratio = limited shrinkage cracks
Roller
Compacted
Concrete
Pavements
• Intermodal Port/ Freight/ Manufacturing
• Ports of Houston, Long Beach, LA, Jacksonville
• Central Freight – Austin, TX
• Honda, Kia, BMW, Saturn – GA, TN, SC
• Jack Daniel’s– Lynchburg, TN
• Proctor & Gamble - PA
• Lowe’s– Rome, GA
• Kansas City Southern, CSX, Norfolk Southern
Historical RCC
Uses
Port of Houston – 2008
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PORTS & DISTRIBUTION CENTERS ARE USING RCC FOR LONG TERM DURABILITY, SPEED OF CONSTRUCTION, & COST SAVINGS
Port of Houston, TX – 3RD Phase > 120 acres total Lowe’s Distribution Center, Rome, GA
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S&B MODULAR
BAYTOWN, TX
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• Owner: Yuma Truck Driving School
• Use Type: Truck Parking
• Year Built: 2013
• Size: 6280 SY
• Volume: 1,215 CY
Project
Information
• Thickness: 7” RCC / Compacted Subgrade
• Traffic: 20 Trucks / day
• Paved 16 ft wide
• RCC paving completed in 3 days
• Used 90% passing ½” Sieve
• Owner knew that asphalt wouldn’t hold up to the turning movements of the trucks
Additional
Details
Yuma Truck Driving School Yuma, AZ - 2013
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USE OF RCC PAVEMENTS IN US
RCC utilization began growing in early 2000’s & is now growing at a faster rate
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2013
Yearly R
CC
SY
Mill
ion
s
Cu
mu
lati
ve R
CC
SY
M
illio
ns
RCC SY
Yearly Sq. Yds
Cumulative Sq. Yds
1975 - 1999 2000-2010 2011-2013
# of Projects 71 99 172
SY 2,999,771 8,933,250 4,993,296
PAVEMENT TYPES & OWNERS ARE CHANGING Industrial Still Remains Largest Application Type, But Roadway are Increasing
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Commercial Industrial Intermodal Port Roadway
# o
f P
roje
cts
Application Type
2011
2012
2013
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Private Public
# o
f P
roje
cts
Owner Type
2011
2012
2013
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• Owner: Yuma County Water Users
• Use Type: Roadway
• Year Built: 2014
• Size: 6280 SY
• Volume: 1,215 CY
Project
Information
• Thickness: 7” RCC / Compacted Subgrade
• Traffic: 20 Trucks / day
• Paved 16 ft wide
• RCC paving completed in 3 days
• Used 90% passing ½” Sieve
• Owner knew that asphalt wouldn’t hold up to the turning movements of the trucks
Additional
Details
YUMA COUNTY WATER USERS Yuma, AZ - 2014
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YUMA EAST WETLANDS HIKE TRAIL Yuma, AZ
• Owner: City of Yuma
• Use Type: Trail
• Year Built: 2013
• Thickness: 5” RCC / Compacted Subgrade
• Quantity: 1,700 CY
Pavement
Design
Information
• City Park, environmentally
sensitive area
• Did not want Asphalt due to
hydrocarbons
• Lacked funds for conventional
concrete
• RCC made it feasible
Additional
Details
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LAMESA DRIVE
MIDLAND, TX
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OVER THE PAST 10 YEARS, DOT’S HAVE PAVED SHOULDERS & SURFACE ROADS USING RCC
I-85 Interchange – Lagrange, GA SR 6 – Powder Springs, GA
US 78 – Aiken, SC
I 285 – Atlanta, GA
I 385 - Greenville, SC I 75 – Tift Cook, GA
South Carolina DOT Projects
US 21 Greystone
Blvd
US 25 SC 5
New State
Road
S. Beltline
Blvd
SC 9
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RICHLAND AV. (US 78) AIKEN, SC
Completed Project
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AGENDA
• Roller Compacted Concrete
• What is it? Where has it Been Used? and Why?
• Pavement Design
• RCC Construction Process
• Recent Advances / Changes
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TYPES OF JOINTS IN RCC PAVEMENTS & LOAD TRANSFER
Details For Use Typical Detail
Contraction (Control)
Joint
• Use at short joint spacing
• Made by saw cut, or tooled
• Early entry cuts = 1/4 depth
• Saw cut within 2 to 6 hours of
paving
Construction Joint
• Use at end of construction day
• Use thickened edge for heavy duty
applications
• Keyways not recommended
Isolation (Expansion)
Joint
• Isolate pavement features with
differential movements
• Do not use at regular spaced joints
in paving lane
• Full thickness, vertical joint, sealed
with compressible material
1) Jointing recommendations should be based on ACI 330
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WHAT SHOULD BE UNDERNEATH RCC?
• Purposes of the subbase are:
• To minimize or eliminate the potential for
pumping
• Provide construction platform
• Use aggregate base or stabilized subgrade if:
• Subgrade is erodible
• Free water is available
• Heavy Wheel load
• Non-uniform soil conditions
• For expansive clay soils, do not use base without
soil stabilization
• Exclude subbase if:
• Non-pumpable subgrade soil (< 45% passing
#200 sieve & PI <6 )
• Pumping is the forceful
displacement of soil
and water from
underneath a concrete
slab
For Port applications, Granular Base are usually required to mitigate pumping
1. Natural subgrade
2. Stabilized subgrade
3. Aggregate base
4. Stabilized aggregate base
5. Combinations of each
Concrete Support options
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RCC THICKNESS DESIGN Streetpave Works Well for Trucks on roadways or parking lots
• Car parking
• Entrance / Exit
• Truck access & parking
• Container stacking
• Crane, Toplifter, Straddle Carriers
Traffic Categories
• Loading characteristics
• # of applications per day
• Design period
• Soil support – K Value
Design Considerations
• Car, light duty vehicles
• Trucks
• Roadways
• Parking lots
• Distribution centers
• Loading characteristics
• # of applications per day
• Design period
• Soil support – K Value
• Designs for concrete & asphalt
• Allows for variable axle load spectrum
• Designs for fatigue and faulting
• Allows for design with/without dowels
• Calculates effective K value for all support
layers
• Multiple reliability levels
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AGENDA
• Roller Compacted Concrete
• What is it? Where has it Been Used? and Why?
• Pavement Design
• RCC Construction Process
• Recent Advances
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THE FINAL SURFACE TYPE WILL DICTATE THE NECESSARY TECHNIQUES & EQUIPMENT NEEDED TO BE SUCCESSFUL
Natural RCC Diamond Ground RCC Asphalt
• Speed Limit < 35 mph
• Ports
• Distribution centers
• Industrial yards
• Residential roads
• Parking lots
• Speed Limit > 35 mph
• Collector / Arterial local roads
• Highway Shoulders
• State routes
• Any pavement type
• Lowest Cost
• Most sensitive to contractor
skill level
• Least smooth
• “Asphalt” appearance
• Medium cost increase
• Increased construction time
• Improved smoothness, skid
resistance
• Reduced noise
• Highest cost
• Increased construction time
• Least sensitive to contractor
skill level
• Improved smoothness, skid
resistance
Ap
pli
ca
tio
ns
F
ac
tors
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THE FINAL SURFACE TYPE DICTATES THE NECESSARY TECHNIQUES & EQUIPMENT NEEDED TO BE SUCCESSFUL
Natural RCC Diamond Ground RCC Asphalt
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1
26
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Natural DG Asphalt
# o
f P
roje
cts
Surface Type
2011
2012
2013
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THE SURFACE TEXTURE OF RCC IS SIMILAR TO ASPHALT PAVEMENT WHILE THE COLOR IS SIMILAR TO CONCRETE
Asphalt RCC
RCC Conventional
Concrete
Diamond Ground
RCC
Diamond Ground
Conventional
Concrete
¾” Max Size ½” Max Size
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RCC MIX DESIGN USES SAME MATERIALS AS CONVENTIONAL CONCRETE, HOWEVER IN DIFFERENT COMBINATIONS
Achieves Similar or Better Engineering Properties Than Conventional Concrete
Typical Engineering
Properties
Conventional
(psi)
RCC
(psi)
Compressive Strength 3,000 - 5,000 4,000 -
10,000
Flexural Strength
(MOR)
500 – 700 500 - 1,000
Elastic Modulus 3.0 – 5.0
million
3.0 – 5.5
million
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47
30
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46
3
0
10
20
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50
60
Cement + FA Coarse Agg Fine Agg Water
% T
ota
l W
eig
ht
Typical Mix Design
Roller Compacted Concrete
Conventional Concrete
Conventional Concrete RCC
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MIXTURE DESIGN PROCEDURE
Step 1: Chose well – graded aggregates
• Selection based on gradation test results of available aggregates
• Multiple aggregates may be evaluated
• Quantity of aggregate sources depends on mixing equipment being utilized (Central mix, pugmill, etc)
• Avoid gaps in gradation
• Finer mixes (above the 45o line) are easier to achieve density at or slightly above optimum moisture
• When paved at or near optimum moisture, the ride is improved
• Can tolerate isolated increases in moisture content without loosing ride
• Coarse mixes are very sensitive to moisture increases
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MIXTURE DESIGN PROCEDURE
Step 2: Select a mid – range cementitious content
• Minimum 450 lbs cement / CY
• 12% Type I Portland cement is selected for the first trial batch
• Based % on weight, so make enough and do not worry about volumes yet
• Mix the cement dry, and then add water
(ASTM D1557)
• Step 3: Develop moisture – density relationship plots
• Perform a modified Proctor test at the selected cement content
• Construct moisture-density relationship curve (Use spreadsheet)
• Determine Maximum Dry Density (MDD) and Optimum Moisture Content (OMC)
Op
tim
um
Mo
istu
re
Maximum Dry Density
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MIXTURE DESIGN PROCEDURE
Step 4: Cast samples to measure compressive strength (ASTM C 1435)
• Calculate trial mix proportions
• Batch RCC materials
– Maintain percent Optimum Moisture Content as determined in step 3
– Use varying cementitious contents such as 10, 12 and 14 percent
• Make compressive strength test cylinders for each cement content
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Intended Goals of the Research
• Increase haul time while maintaining workability
• Retain moisture
• Improve surface finish
• Increase compressive strength
• Increase density behind paver
• Currently using Grace VSC500 @ 3 cwt
ADMIXTURES ARE BEING USED TO IMPROVE WORKABILITY AND INCREASE HAUL TIME
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35 37 45
30
33 32
35
0 50 100 150
Tim
e (s
eco
nd
s)
Elapsed Time (Mins)
Vebe Time
Control
VSC 500
8 7.9
7.8
7
7.5
7.1 7.1
7
0 50 100 150M
ois
ture
Co
nte
nt
(%)
Elapsed Time (mins)
Moisture Content
Control
VSC 500
3520 3100
3750 4040
0 120
Co
mp
ress
ive
Stre
ngt
h (
psi
)
Elapsed Time (Mins)
Compressive Strength (5 Day)
Control
VSC 500
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TECHNOLGIES ARE BEING USED TO IMPROVE SURFACE DURABILITY & APPEARANCE
• Colloidal Silica
• Reacts with cement to increase paste
• Improves surface appearance
• Reduces surface dusting
• Improves surface durability
RCC
Surface
Pro
Schmitz Hammer (Rebound Test Results) No Day1 Day1 @ 4:1 Day1 @ 8:1
Edge Center Edge Center Edge Center 30 24 28 26 26 30 24 14 28 31 23 30 22 25 31 30 28 33 26 26 34 30 25 33 16 34 29 26 26 23 21 30 25 35 23 26 20 25 32 40 19 24 34 26 24 30 33 25 18 30 34 28 34 28 24 31 31 38 29 21
AVERAGE 23.5 26.5 29.6 31.4 26.6 27.3 PSI 2800 3250 3800 4250 3250 3400
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Mixer Type Description Factors to Consider
Twin Shaft –
Horizontal
Mixer - Batch
Type
• High production rates: 50 to 220 CY / hr
• Excellent mixing efficiency for dry materials
• Mobile – 1 or 2 loads, easily set up in 1 day
• Batch setup may induce load to load moisture variability
• Mixing system only – requires a batching system
• Same capabilities & requirements as operating ready mix plant
• No permitting required
• Easy to incorporate admixtures, fibers, etc
Pugmill –
Continuous
Twin Shaft
• High production rates: 50 to 300+CY / hr
• Excellent mixing efficiency for dry materials
• Highly consistent mix properties, minimal
moisture fluctuation – easy adjustment
• Mobile – 1 load, easily erected on site &
calibrated in 1 day
• Need to find good location, obtain permits
• Self contained – Gen set, batch house
• 2 to 3 man operation
• Limited to 2 aggregate sizes
WE RECOMMEND USING A TWIN SHAFT OR PUGMILL MIXER FOR PRODUCING RCC
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RCC IS PLACED WITH HIGH DENSITY ASPHALT PAVERS Achieving Density & Smoothness is Critical
• High density screed (Vogele or ABG Titan)
• High initial density from paver (90% - 96%)
• Smoother surface due to higher initial density
• Less “roll down” to achieve final density
• High-production (6 to 8 ft/min)
• 10 to 30 ft width
• Lift thick range: 4” to 9”
High Density Paver
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ROLLERS ARE USED TO ACHIEVE DENSITY AND PROVIDE FINISH
• Initial: 10 - 12 ton static & vibratory roller
• Establish roll pattern (check density a lot!)
• Adjust roll pattern based on moisture content
• Compact to 98% density - wet
• Adjust moisture content if needed – impacts
smoothness & compaction
• Finer mixes achieve density easier
• Combination, dual steel or rubber tired
• Maximum weight - 6 short ton
• Remove roller marks
• Once completed, keep roller off of the area
Initial Compaction Finish Rolling
Fairforest Way
Greenville, SC Grape Creek Road – San Angelo, TX
Fairforest Way
Greenville, SC
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• Need high density paver
• Attach shoe to screed
• Maximum angle 15o
• Use plate tamper to improve edge durability
• No saw cutting required
• Pave adjacent lane next day
• Lowest cost
• Pave for 50 minutes then move back to
beginning and match original lane
• Do not compact original lane within 2 ft
of edge until adjacent lane is paved
• Recommend a longitudinal saw cut
• Use small loader to create fresh vertical
transverse joint
• Move quickly – keep moist!
• Coordination is key, avoid breakdowns
Angular Cold Joint Fresh (Hot) Joints
• Pave width of lane
• Saw cut full depth early next morning
• Remove with blade & loader
• Expect waste
• Reduce waste with paver shoe & plate tamper
• Pave adjacent lane and match thickness of existing lane
• Good performance, limited load transfer
Vertical Cold Joint
LONGITUDINAL JOINTS CAN BE BUILT 3 DIFFERENT WAYS
2 ft
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MANHOLES & CURBS ARE EASILY INCORPORATED INTO STREETS
• Traditional curb & gutter placed before RCC
• Serves as compaction aid
• Joint may need to be sealed
• Alternatively, ribbon curb can be placed
• Drill & grout rebar into cold RCC
• Place ribbon curb afterwards
• Plywood plate is placed on top of hole before RCC is placed
• After paving, two methods are available:
• Dig RCC immediately while fresh, place manhole and re - compact material with hand tampers
• Saw cut hardened RCC, place manhole, tie in with conventional concrete
Curb & Gutter Manholes, Inlets
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QC / QA PROCESS INCLUDES TESTING FOR DENSITY, MOISTURE CONTENT & COMPRESSIVE STRENGTH
• Tested with nuclear gage in direct mode
• Test density behind paver & after roller to establish rolling patterns to achieve density
• Achieve 98% of modified proctor wet density
• Nuclear gage gives general moisture fluctuation indication - Calibrate with oven dried moisture
• Oven dried is most accurate
• Cylinders prepared with vibratory hammer according to ASTM C1435
• 3 to 4 cylinders per set
• Strength timing often depends on traffic opening (1, 3, 7, 28 days)
• Cores can be obtained where density is not being achieved
Compressive Strength Moisture & Density
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WHEN CURED & SAW CUT RCC PERFORMANCE IMPROVES
• Applied at same rate or slightly higher than conventional concrete
• Ensure uniformity with application process
• Apply as soon as possible behind roller operation
• Recommend WR Meadows 1200 to 1600
• Ensures durable surface
Curing Saw Cut & Fill Joints
• More aesthetically pleasing
• Early entry saw very effective, shortly following placement
• Recommend sawing within 2 - 6 hours to avoid uncontrolled cracking
• Depth: 1” to 2”
• Spacing: Maximum 36 times thickness
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SOME FACTORS TO CONSIDER WHEN BIDDING PROJECTS
• Volume of RCC paving on the project
• Site geometry
• Project phasing
• Pavement thickness
• Pavement width
• Final surface characteristics
• Traffic control
• Opening to traffic
• Daily working schedule
![19874619 RCC Design Sheets[1]](https://img.pdfslide.net/doc/110x75/577d397a1a28ab3a6b99d487/19874619-rcc-design-sheets1.jpg)
