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Streets and Local Roads
Proper Design Details for PCC Pavement
Performance

Mike Byers
Indiana Chapter – American Concrete...
Streets & Local Roads
Chapter/States Associations of ACPA
North
Dakota

Northwest

Minnesota
Wisconsin

South
Dakota
Color...
SLR Pavement Markets
 New/Reconstruction of
Concrete Pavements
 Concrete Overlays
Unbonded
Whitetopping
Ultra-Thin Wh...
Thickness Design Procedures
Empirical Design
Procedures
 Based on observed
performance
AASHO Road Test

Mechanistic De...
New Design Tools for SLR
 MEPDG – MechanisticEmperical Design Guide
 StreetPave Software
Concrete Thickness
Asphalt In...
Equivalent Pavement Design
StreetPave Software
 Concrete pavement thickness
design based on revised criteria
 Asphalt equivalent section based
on c...
Different Pavement Types
Concrete Section

Asphalt Section
Asphalt Layer

Subbase
Subgrade

Base
Subbase
Subgrade
How Pavements Carry Loads
7000 lb.

7000 lb.

pressure < 1-3 psi
pressure
≈ 6-10 psi

Concrete’s Rigidness spreads the loa...
Comparison of Concrete vs. Asphalt
 It’s not the same old
Asphalt and
Concrete anymore!
 Just look at the Gas
Pumps!
 G...
Streets and Local Roads Thickness
Design Procedure
Longitudinal joint

Surface smoothness
or rideability

Thickness Design...
Concrete Pavement Types
 Jointed Plain
Undoweled
Doweled

 Jointed Reinforced
 Continuously
Reinforced
Jointed Plain
Plan

8 – 15 ft

Profile
or
Jointed Plain
Agencies Designing Jointed Plain
Concrete Highway Pavements

Use jointed plain designs
Do not use jointed plain designs
Concrete Pavement Design Requires
Selecting Appropriate Features
 Subgrade modification
 Drainage system
 Subbase
 Joi...
Optimize

Cost
Performance

Now Using Mechanistic-Empirical Design (MEPDG) to
Optimize
Principles of Design
Load stresses

Thickness

Curling/Warping stresses

Jointing

Volume change stresses
SLR Pavement Design
 Street classification and
traffic
 Geometric design
 Subgrades and subbases
 Concrete quality
 T...
Street Class Description

Two-way
Average Daily
Traffic
(ADT)

Two-way Average
Daily Truck
Traffic (ADTT)

Less than 200

...
Geometric Design
 Utilities
 Increase Edge Support
Integral Curb
Tied Curb & Gutter
Widened Lanes (2 feet no parking)...
Subbase vs. NO Subbase
For Concrete Pavements

Subbase
Subgrade
Subgrade and Subbases
For Concrete Pavements

Subbase
Subgrade
Subgrade and Subbases
Subgrade
Natural ground, graded, and
compacted on which the pavement is
built.

Subbase
Layer of...
UNIFORMITY:
The Key To

GOOD
PAVEMENT
PERFORMANCE
Design for Uniform Support
Three Major Causes for Non-Uniform Support
 Expansive Soils
 Differential Frost Heave
 Pumpi...
Subbase vs. NO Subbase
 Presence of fine-grained soil
 Presence of water
 Sufficient volume of trucks to
cause soil pum...
Subgrade Properties
Modulus of Subgrade
Reaction, k-value

Plate-Load Test
Reaction

Plate load on subgrade
k = Plate defl...
Subgrade Properties
Plate-load test is rarely performed
time consuming & expensive

Estimate k-value by correlation to ...
Subgrade Properties
Correlated k-values for Subgrade Support
Historical
k-values
(pci)

California
Bearing Ratio
(CBR), %
...
Subgrade and Subbases
Design Summary
Subgrade strength is not a critical element in the
thickness design.
Has little imp...
Subgrade and Subbases
Performance Summary
Proper design and construction are absolutely necessary
if the pavement is to p...
Subbase Effects
At the AASHO Road Test,
concrete pavements with
granular bases could carry
about 30% more traffic.
The cur...
Drainable Subbase??
 Aggregate Quality – marginal Dcracking?
 Traffic Level – high volume may
warrant drainable subbase
...
Concrete Quality
 Portland Cement

Materials

 Supplementary
Cementitious Materials
 Aggregates
 Chemical Admixtures
...
Concrete Quality
Recommended Air Contents for Durable Concrete
Maximum size aggregate

Total target air content, percent *...
Concrete Quality
Maximum Permissible Water-Cement Ratio for Durable
Concrete Pavement
Type of exposure
Freezing/thawing
wi...
Basics of Thickness Design

C

T
The latest design and cost analysis tool from ACPA…
 Determine and compare thickness requirements and costs
for concrete ...
Thickness Design for Streets and Local Roads
StreetPave User Inputs & Outputs
 Global Settings
Region
Units (English or...
Design Example – Inputs
 Design life = 30 years
 k-value = 100 pci
 Concrete flexural strength = 600 psi
 Load transfe...
Thickness Design Procedure
Design controlled
by:

 Fatigue usually controls design of light-traffic
pavements
Single-axl...
Thickness Design Procedure
Concrete Properties
 Flexural Strength
(Modulus of Rupture,
ASTM C 78)

Third-point Loading

...
Thickness Design Procedure
Concrete Properties

Compressive Strength f’c

S’c = 8-10 √ f’c

Head of
Testing
Machine

Cylin...
Basics of Thickness Design
Stress / Fatigue

C

T

 Compressive strength: ~4000 psi
 Flexural strength: ~600 psi
Strength Correlations
MR = 7.5 x f'c^(0.5)

MR = 9 x f'c^(0.5)

MR = 10 x f'c^(0.5)

800
750

Flexural Strength, psi

700
...
Concrete Strength Properties
If specify minimum flexural strength
at 28-day of 550 psi & allow 10%
of beams to fall below ...
Thickness Design Procedure
Concrete Properties

Comparison of f’c, MR, and Required Thickness
Compressive
Strength (psi)

...
Design Period/Life
20 to 35 years is commonly used
Shorter or longer design period may be
economically justified in some...
Design Reliability
 Practically everything associated with pavement
design is variable
Variability in mean design inputs...
Reliability
Levels of Reliability for Pavement Design
Functional Classification of
Roadway

Recommended Reliability
Urban
...
Thickness Design

Combined Reliability & Slabs
Cracked Spreadsheet

Recommended Levels of Slab Cracking by Roadway Type
Ro...
Basics of Thickness Design
Deflection / Erosion

 Higher k-value will lower
deflections
 Load transfer will lower
deflec...
Concrete Pavement Design
For Municipal Streets

Load Transfer (slabs ability to share its load with neighboring slabs)
 D...
Dowels vs. NO Dowels
Load Transfer
L=

x
U=

0

The slabs ability to share its
load with its neighboring
slab
 Dowels

Po...
Load Transfer Efficiency
Load Transfer Mechanism LTE, %
aggregate interlock
stabilized base
dowel bars

30 - 80
50 - 90
80...
Aggregate Interlock

Shear between aggregate particles
below the initial saw cut
Aggregate Interlock
Design - Erosion
Conditions for Pumping
 Subgrade soil that will go into
Suspension
 Free water between slab and
subgrad...
Dowel bars
 Lengths from 15-18 in.
 6.0 in. min. embedment
length
 Diameter
1.00 - 1.25 in. for SLR

 Epoxy or other ...
Dowel Recommendations
 Dowels recommended when
ADTT is greater than or equal to
80:
If pavement thickness is 6” or less
...
Faulting Model
Faulting, in
0.20

Dense-graded base
No dowel

0.15

Permeable base
No dowel

0.10

Dense-graded base
1-in ...
Construction of Concrete Pavement










Plant Operations
Central Mixed Concrete
Plant Operations
Truck Mixed ...
Construction Specifications
 Smoothness
10-20 ft. Straightedge
Profilograph Index

 Texture
Speeds less than 40 mph
...
Curing and Protection
Curing
 Curing is one of the most
important steps in quality
concrete construction and
one of the most neglected.
 Effec...
Curing
Curing requires adequate —
 Moisture
 Temperature
 Time
If any of these factors are
neglected, the desired
prope...
Membrane Curing of
Concrete
Evaporation from water
surface

Partially saturated

Curing
membrane

Saturated
Concrete
Curing
 The simplest, most economical and
widely used method is a liquid
membrane which is sprayed on the
surface of a sl...
Effect of Adequate Curing on
Hardened Concrete
Increased
 Strength
 Watertightness
 Abrasion resistance
 Freeze-thaw r...
Effect of Curing on Strength
Development
The latest design and cost analysis tool from ACPA…
 Determine and compare thickness requirements and costs
for concrete ...
SLR Publications

Information SheetMaturity Testing of ConcreteInformation Sheet- (IS
Concrete Pavement for
GA Business &C...
Indiana Concrete
Resources

Jerry Larson

Mike Byers
Pat Long

Chris Tull, P.E., LEED AP
Questions?
Contacts for further information
www.irmca.com

www.indianaconcretepavement.com
INDIANA CHAPTER
Thank You
S60 mb proper_20_pccp_20design_20details_20for_20performance_20__20road_20school_202011
S60 mb proper_20_pccp_20design_20details_20for_20performance_20__20road_20school_202011
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  1. 1. Streets and Local Roads Proper Design Details for PCC Pavement Performance Mike Byers Indiana Chapter – American Concrete Pavement Association
  2. 2. Streets & Local Roads Chapter/States Associations of ACPA North Dakota Northwest Minnesota Wisconsin South Dakota ColoradoWyoming Western States Utah Michigan Iowa Northeast Indiana Illinois Ohio Missouri-Kansas Kentucky Oklahoma-Arkansas Southeast Louisiana American Concrete Pavement Association
  3. 3. SLR Pavement Markets  New/Reconstruction of Concrete Pavements  Concrete Overlays Unbonded Whitetopping Ultra-Thin Whitetopping (UTW)  Concrete Inlays Intersections Roundabouts Bus Pads Alleys  Concrete Pavement Restoration
  4. 4. Thickness Design Procedures Empirical Design Procedures  Based on observed performance AASHO Road Test Mechanistic Design Procedures  Based on mathematically calculated pavement responses PCA Design Procedure (PCAPAV) StreetPave (ACPA Design Method) Ottawa, Illinois (approximately 80 miles southwest of Chicago) between 1956 and 1960
  5. 5. New Design Tools for SLR  MEPDG – MechanisticEmperical Design Guide  StreetPave Software Concrete Thickness Asphalt Institute Design Thickness Life Cycle Cost Analysis  Information Sheet IS184  Thickness Design Manual for Concrete Streets and Local Roads EB109  Equivalent Pavement Design Charts What’s Equivalent
  6. 6. Equivalent Pavement Design
  7. 7. StreetPave Software  Concrete pavement thickness design based on revised criteria  Asphalt equivalent section based on converted total carrying capacity  Life-Cycle cost analysis based on initial costs of equivalent pavements and predicted maintenance
  8. 8. Different Pavement Types Concrete Section Asphalt Section Asphalt Layer Subbase Subgrade Base Subbase Subgrade
  9. 9. How Pavements Carry Loads 7000 lb. 7000 lb. pressure < 1-3 psi pressure ≈ 6-10 psi Concrete’s Rigidness spreads the load over a large area and keeps pressures on the subgrade low.
  10. 10. Comparison of Concrete vs. Asphalt  It’s not the same old Asphalt and Concrete anymore!  Just look at the Gas Pumps!  Gasoline prices are a good indicator of what asphalt pavement cost!
  11. 11. Streets and Local Roads Thickness Design Procedure Longitudinal joint Surface smoothness or rideability Thickness Design Transverse joint Surface Texture Concrete materials Dowel bars Tiebars Subgrade Subbase or base
  12. 12. Concrete Pavement Types  Jointed Plain Undoweled Doweled  Jointed Reinforced  Continuously Reinforced
  13. 13. Jointed Plain Plan 8 – 15 ft Profile or
  14. 14. Jointed Plain
  15. 15. Agencies Designing Jointed Plain Concrete Highway Pavements Use jointed plain designs Do not use jointed plain designs
  16. 16. Concrete Pavement Design Requires Selecting Appropriate Features  Subgrade modification  Drainage system  Subbase  Joint Spacing  15 ft  18 ft  Dowels  Thickness  6 in  8 in  10 in  Reinforcement  Joint Sealant  None  Hot pour  Silicone  Preformed  Surface Texture  Transverse tine  Burlap drag  Shoulder  Asphalt  Concrete
  17. 17. Optimize Cost Performance Now Using Mechanistic-Empirical Design (MEPDG) to Optimize
  18. 18. Principles of Design Load stresses Thickness Curling/Warping stresses Jointing Volume change stresses
  19. 19. SLR Pavement Design  Street classification and traffic  Geometric design  Subgrades and subbases  Concrete quality  Thickness design  Jointing  Construction specifications
  20. 20. Street Class Description Two-way Average Daily Traffic (ADT) Two-way Average Daily Truck Traffic (ADTT) Less than 200 2-4 4.0 - 5.0 in. (100-125 mm) 200-1,000 10-50 5.0 - 7.0 in. (125-175 mm) Typical Range of Slab Thickness Light Residential Short streets in subdivisions and similar residential areas – often not throughstreets. Residential Through-streets in subdivisions and similar residential areas that occasionally carry a heavy vehicle (truck or bus). Collector Streets that collect traffic from several residential subdivisions, and that may serve buses and trucks. 1,000-8,000 50-500 5.5 - 9.0 in. (135-225 mm) Business Streets that provide access to shopping and urban central business districts. 11,000-17,000 400-700 6.0 - 9.0 in. (150-225 mm) Industrial Streets that provide access to industrial areas or parks, and typically carry heavier trucks than the business class. 2,000-4,000 300-800 7.0 - 10.5 in. (175-260 mm) Arterial Streets that serve traffic from major expressways and carry traffic through metropolitan areas. Truck and bus routes are primarily on these roads. 4,000-15,000 (minor) 4,000-30,000 (major) 300-600 6.0 - 9.0 in. (150-225 mm) 7.0 - 11.0 in. (175-275 mm) 700-1,500
  21. 21. Geometric Design  Utilities  Increase Edge Support Integral Curb Tied Curb & Gutter Widened Lanes (2 feet no parking) Parking Lanes Rural Areas – Tied Concrete Shoulders  Street Widths Minimum width of 25 ft. Maximum Cross Slope of 2 percent (¼” per ft.) Traffic Lanes 10-12 feet Parking Lanes 7-8 feet
  22. 22. Subbase vs. NO Subbase For Concrete Pavements Subbase Subgrade
  23. 23. Subgrade and Subbases For Concrete Pavements Subbase Subgrade
  24. 24. Subgrade and Subbases Subgrade Natural ground, graded, and compacted on which the pavement is built. Subbase Layer of material directly below the concrete pavement.
  25. 25. UNIFORMITY: The Key To GOOD PAVEMENT PERFORMANCE
  26. 26. Design for Uniform Support Three Major Causes for Non-Uniform Support  Expansive Soils  Differential Frost Heave  Pumping (loss of support)
  27. 27. Subbase vs. NO Subbase  Presence of fine-grained soil  Presence of water  Sufficient volume of trucks to cause soil pumping (> 100 trucks/day)  Pavements on > 15% grade
  28. 28. Subgrade Properties Modulus of Subgrade Reaction, k-value Plate-Load Test Reaction Plate load on subgrade k = Plate deflection on subgrade 5.0 psi k = 0.5 in = 100 psi / in. Stacked Plates Pressure Gauge Subgrade
  29. 29. Subgrade Properties Plate-load test is rarely performed time consuming & expensive Estimate k-value by correlation to other tests e.g. California Bearing Ratio (CBR) or R-value tests Lean concrete subbases increases k-value substantially
  30. 30. Subgrade Properties Correlated k-values for Subgrade Support Historical k-values (pci) California Bearing Ratio (CBR), % Resistance Value (R-value) (ASTM D 1183) (ASTM D 2844) Low 75 - 120 2.5 - 3.5 10 - 22 Sand and sand-gravel with moderate silt/clay Medium 130 - 170 4.5 - 7.5 29 - 41 Sand and sand-gravel with little or no silt/clay High 180 - 220 8.5 - 12 45 - 52 Type Fine-grained with high amounts of silt/clay Amount of Support
  31. 31. Subgrade and Subbases Design Summary Subgrade strength is not a critical element in the thickness design. Has little impact on thickness. Need to know if pavement is on: Subgrade (k ≈ 25 MPa/m (100 psi/in.)), Granular subbase (k ≈ 40 MPa/m (150 psi/in.)), Asphalt treated subbase (k ≈ 80 MPa/m (300 psi/in.)) Cement treated/lean concrete subbase (k ≈ 125 MPa/m (500 psi/in.)).
  32. 32. Subgrade and Subbases Performance Summary Proper design and construction are absolutely necessary if the pavement is to perform. Must be uniform throughout pavement’s life. Poor subgrade/subbase preparation can not be overcome with thickness. Any concrete pavement, built of any thickness, will have problems on a poorly designed and constructed subgrade or subbase.
  33. 33. Subbase Effects At the AASHO Road Test, concrete pavements with granular bases could carry about 30% more traffic. The current design procedures allows concrete pavements built with granular bases to carry about 5 - 8% more traffic.
  34. 34. Drainable Subbase??  Aggregate Quality – marginal Dcracking?  Traffic Level – high volume may warrant drainable subbase  Edge drains behind curb still good detail
  35. 35. Concrete Quality  Portland Cement Materials  Supplementary Cementitious Materials  Aggregates  Chemical Admixtures  Water Testing
  36. 36. Concrete Quality Recommended Air Contents for Durable Concrete Maximum size aggregate Total target air content, percent * Severe Exposure Moderate Exposure in. mm 3/8 9.5 7.5 6 1/2 12.5 7 5.5 3/4 19.0 6 1 25.0 6 4.5 1½ 37.5 5.5 4.5 2 50.0 5 4 Suggest 6.5 5
  37. 37. Concrete Quality Maximum Permissible Water-Cement Ratio for Durable Concrete Pavement Type of exposure Freezing/thawing with deicing chemicals Severe sulfate exposure [water-soluble sulfate (SO4) in soil > 0.20 % by weight] Moderate sulfate exposure [water-soluble sulfate (SO4) in soil of 0.10 to 0.20 % by weight] Maximum water-cementitious ratio by weight 0.45 INDOT max 0.42 0.45 0.50
  38. 38. Basics of Thickness Design C T
  39. 39. The latest design and cost analysis tool from ACPA…  Determine and compare thickness requirements and costs for concrete and asphalt pavements using StreetPave. Features:  Updated mechanistic design method for concrete pavement  Fatigue and erosion analysis  Jointing spacing & load transfer recommendations  Thickness rounding and reliability considerations  Analysis of existing concrete pavements  Asphalt design based on the Asphalt Institute method  Comparison to equivalent concrete pavement  Life cycle cost analysis module  Printable summary reports and charts  Design summary  Design factor sensitivity & life-cycle plots  User-friendly format and features  Walkthrough Wizard  Help information for all inputs  Compatible with Windows™ 95, 98, NT, 2000, XP
  40. 40. Thickness Design for Streets and Local Roads StreetPave User Inputs & Outputs  Global Settings Region Units (English or Metric) Terminal Serviceability Percent Slabs Cracked at end of design Life  Design Life  Reliability  Traffic  Pavement Properties  Thickness/Dowel/Jointing Recommendations
  41. 41. Design Example – Inputs  Design life = 30 years  k-value = 100 pci  Concrete flexural strength = 600 psi  Load transfer (dowels) = yes  Edge support = yes  Traffic category = Collector  2-way ADTT = 100  Reliability = 80%  Percent Slabs Cracked = 15%
  42. 42. Thickness Design Procedure Design controlled by:  Fatigue usually controls design of light-traffic pavements Single-axles usually cause more fatigue damage  Erosion usually controls design of undoweled medium- and heavy-traffic pavements Tandem-axles usually cause more erosion damage Tridem-axles usually cause more erosion damage
  43. 43. Thickness Design Procedure Concrete Properties  Flexural Strength (Modulus of Rupture, ASTM C 78) Third-point Loading Avg. 28-day strength in 3rd-point loading d=L/ 6  Other Factors Concrete Strength Gain with Age Fatigue Properties L/3 Span Length = L
  44. 44. Thickness Design Procedure Concrete Properties Compressive Strength f’c S’c = 8-10 √ f’c Head of Testing Machine Cylinder Depth f’c = Compressive Strength (psi) S’c = Flexural Strength (psi)
  45. 45. Basics of Thickness Design Stress / Fatigue C T  Compressive strength: ~4000 psi  Flexural strength: ~600 psi
  46. 46. Strength Correlations MR = 7.5 x f'c^(0.5) MR = 9 x f'c^(0.5) MR = 10 x f'c^(0.5) 800 750 Flexural Strength, psi 700 650 600 550 500 450 400 350 300 2000 2500 3000 3500 4000 4500 Compressive Strength, psi 5000 5500 6000
  47. 47. Concrete Strength Properties If specify minimum flexural strength at 28-day of 550 psi & allow 10% of beams to fall below minimum: Percentage of 28-day Strength 160 140 120 100 Type I (GU) Type III (HE) 80 60 40 3d 7d 28d 3m Age 1y 3y 5y 10y 20y STEP 1 Estimate SDEV: 9% for typical ready mix. SDEV = 550 * 0.09 = 50 psi STEP 2 S’c design = S’c minimum + z * SDEV S’c design = 550 + 1.282 * 50 S’c design = 614 psi
  48. 48. Thickness Design Procedure Concrete Properties Comparison of f’c, MR, and Required Thickness Compressive Strength (psi) Flexural Strength Design Thickness (psi) (inches) 3000 450 – 550 (500) 6.5 (6.43) PCA 7.0 4000 510 – 630 (600) 5.5 (5.25) PCA 6.5 5000 570 – 710 (700) 5.0 (4.86) PCA 6.0 Life 30 years, Collector (2), k-value 162, Reliability 80 %, plus C & G, 2 % annual growth
  49. 49. Design Period/Life 20 to 35 years is commonly used Shorter or longer design period may be economically justified in some cases High performance concrete pavements Long-life pavements A special haul road to be used for only a few years Cross-overs Temporary lanes
  50. 50. Design Reliability  Practically everything associated with pavement design is variable Variability in mean design inputs—traffic, materials, subgrade, climate, and so on Error in performance prediction models  In StreetPave design, the fatigue variability can be modeled and applied as an adjustment factor
  51. 51. Reliability Levels of Reliability for Pavement Design Functional Classification of Roadway Recommended Reliability Urban Rural Interstates, Freeways, and Tollways 85 - 99 80 – 99 Principal Arterials 80 - 99 75 – 95 Collectors 80 - 95 75 – 95 Residential & Local Roads 50 - 80 50 – 80
  52. 52. Thickness Design Combined Reliability & Slabs Cracked Spreadsheet Recommended Levels of Slab Cracking by Roadway Type Roadway Type Recommended Percent of Slabs Cracked at End of Design Life (Default) 15% Interstate Highways, Expressways, Tollways, Turnpikes 5% State Roads, Arterials 10% Collectors, County Roads 15% Residential Streets 25%
  53. 53. Basics of Thickness Design Deflection / Erosion  Higher k-value will lower deflections  Load transfer will lower deflections
  54. 54. Concrete Pavement Design For Municipal Streets Load Transfer (slabs ability to share its load with neighboring slabs)  Dowels  Aggregate Interlock  Edge Support Tied curb & gutter Integral curb & gutter Parking lane Tied concrete L= x U= 0 Poor Load Transfer = L x/2 Good Load Transfer U= x/2
  55. 55. Dowels vs. NO Dowels Load Transfer L= x U= 0 The slabs ability to share its load with its neighboring slab  Dowels Poor Load Transfer High Traffic Volumes (Pavements > 8 in.) (> 120 Trucks/day)  Aggregate Interlock L= x Good Load Transfer U= x Low Traffic Volumes (Pavements < 7 in.)
  56. 56. Load Transfer Efficiency Load Transfer Mechanism LTE, % aggregate interlock stabilized base dowel bars 30 - 80 50 - 90 80 - 95
  57. 57. Aggregate Interlock Shear between aggregate particles below the initial saw cut
  58. 58. Aggregate Interlock
  59. 59. Design - Erosion Conditions for Pumping  Subgrade soil that will go into Suspension  Free water between slab and subgrade  Frequent heavy wheel loads / large deflections
  60. 60. Dowel bars  Lengths from 15-18 in.  6.0 in. min. embedment length  Diameter 1.00 - 1.25 in. for SLR  Epoxy or other coating used in harsher climates for corrosion protection
  61. 61. Dowel Recommendations  Dowels recommended when ADTT is greater than or equal to 80: If pavement thickness is 6” or less dowels not recommended If pavement thickness is 6.5” to 7.5” use 1” dowels If pavement thickness is 8” or greater use 1¼“ dowels
  62. 62. Faulting Model Faulting, in 0.20 Dense-graded base No dowel 0.15 Permeable base No dowel 0.10 Dense-graded base 1-in dowel 0.05 0.00 0 Dense-graded base 1.25-in dowel 5 10 15 Traffic, million ESALs 20
  63. 63. Construction of Concrete Pavement          Plant Operations Central Mixed Concrete Plant Operations Truck Mixed Concrete Paving Operations Slipform Paving Paving Operations Fixed Form Paving Saw & Seal Central Mix Concrete Batch Plant
  64. 64. Construction Specifications  Smoothness 10-20 ft. Straightedge Profilograph Index  Texture Speeds less than 40 mph Burlap Drag Astroturf Drag
  65. 65. Curing and Protection
  66. 66. Curing  Curing is one of the most important steps in quality concrete construction and one of the most neglected.  Effective curing is absolutely essential for surface durability.  Durability = resistance to
  67. 67. Curing Curing requires adequate —  Moisture  Temperature  Time If any of these factors are neglected, the desired properties will not develop
  68. 68. Membrane Curing of Concrete Evaporation from water surface Partially saturated Curing membrane Saturated Concrete
  69. 69. Curing  The simplest, most economical and widely used method is a liquid membrane which is sprayed on the surface of a slab as soon as possible after finishing.  Apply at manufacture’s rate of coverage.  Perform field check to verify application rate.
  70. 70. Effect of Adequate Curing on Hardened Concrete Increased  Strength  Watertightness  Abrasion resistance  Freeze-thaw resistance  Volume stability
  71. 71. Effect of Curing on Strength Development
  72. 72. The latest design and cost analysis tool from ACPA…  Determine and compare thickness requirements and costs for concrete and asphalt pavements using StreetPave. Features:  Updated mechanistic design method for concrete pavement  Fatigue and erosion analysis  Jointing spacing & load transfer recommendations  Thickness rounding and reliability considerations  Analysis of existing concrete pavements  Asphalt design based on the Asphalt Institute method  Comparison to equivalent concrete pavement  Life cycle cost analysis module  Printable summary reports and charts  Design summary  Design factor sensitivity & life-cycle plots  User-friendly format and features  Walkthrough Wizard  Help information for all inputs  Compatible with Windows™ 95, 98, NT, 2000, XP
  73. 73. SLR Publications Information SheetMaturity Testing of ConcreteInformation Sheet- (IS Concrete Pavement for GA Business &Commuter Aircraft Information SheetLongevity and Performance of DG Pavements Information SheetSpecification Guideline for Dowel Bar Retrofit www.pavement.com Engineering Bulletin- (EB Early Cracking Causes/Solutions Engineering Bulletin-(EB
  74. 74. Indiana Concrete Resources Jerry Larson Mike Byers Pat Long Chris Tull, P.E., LEED AP
  75. 75. Questions? Contacts for further information www.irmca.com www.indianaconcretepavement.com INDIANA CHAPTER
  76. 76. Thank You

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