Concrete Pavement:

Selection of Concrete Materials

Jerry L. Larson IRMCA Indiana LTAP Basics of a Good Road INDIANA CHAPTER

Basic Components of a Concrete Pavement

Longitudinal joint Surface smoothness or rideability Transverse joint Thickness Design Surface Texture Concrete materials Dowel bars Tiebars Subgrade Base

How Pavements Carry Loads

6600 LBS.

6600 LBS.

Flexible Pavement pressure < 0.2 MPa pressure

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2.0 MPa Concrete’s rigid panels spread the load over a large area reducing pressure on the sub grade.

Conventional Concrete Pavement Types Full Depth – New Construction – Reconstruction Overlays Thin Overlays

Concrete Design “Optimize” Cost Performance

Subbase vs. NO Subbase Heavy Traffic?? > 120 Trucks/day = subbase Fine grain soils prone to erosion Presence of moisture/water – Potential pumping Presence of all or most above conditions suggests need for subbase

Successful Concrete Pavement Design Requires Selecting Appropriate Features       Subgrade modification Drainage system Subbase Joint Spacing   18 ft 15 ft Dowels Thickness    8 in 10 in 12 in     Reinforcement Joint Sealant     None Hot pour Silicone Preformed Surface Texture   Transverse tine Burlap drag Shoulder   Asphalt Concrete

* ** Concrete Mix Design Material INDOT Class A INDOT Class C Fast Track (per cubic yard) Cement (Type I) Cement (Type III) 564 lbs.

Fly Ash Coarse Aggregate Fine Aggregate Water:Cement Ratio * Water Reducer Air Entrainer ** 1750 lbs.

1250 lbs.

0.45 max.

yes yes 708 lbs.

(658 lbs.) (50 lbs.) 1425 lbs.

1350 lbs.

0.42

yes yes Maximum top size coarse aggregate 0.75 - 1.0 in.

Air content 6% + 1.5%

Durability = Performance Quality Materials – Aggregate – AP Approved, uniform gradation – Minimum Cement Content – Approved Admixtures Proper Mix Design – Control to Design Moisture/Water Control Air Entrainment – 6% + 1.5% Proper Curing – Liquid membrane applied @ manufacturer’s suggested rate

Plan Panel Design

12 – 20 FT

Profile or

Jointing Spacing based on thickness – 6” thick – 12’ joint spacing – > 12” thick – 18’ joint spacing > 12” thick - saw 1/3 the depth If not specifying dowels – can skew joints 1’ in 12’ across pavement High volume traffic – seal joints with silicone or neoprene Low volume traffic – seal joints with hot pour rubberized asphalt

Dowels or NO Dowels The slabs ability to share its load with its neighboring slab – Dowels High Traffic Volumes (Pavements > 8 in.) – Aggregate Interlock Low Traffic Volumes (Pavements < 7 in.) L = x Poor Load Transfer U = 0 L = x Good Load Transfer U = x

Surface Texture Tineing

Surface Texture Light Broom

Surface Texture Drag Finish

Construction - Reconstruction

Construction - Reconstruction

Overlays Expected Performance – UTW (2” – 4”) – 15 to 20 years – Thicker overlays (4” – 6”) 20 to 25 years Condition of existing sub-grade/pavement Clearance issues – if none, can build on top of old PCCP or HMA pavement

Concrete Resurfacing Applications Concrete overlays for concrete pavements: – Bonded Concrete Overlays – Unbonded Concrete Overlays Concrete overlays for asphalt pavements: – Conventional Whitetopping – Ultra-Thin Whitetopping

Unbonded Overlay Consists of thick concrete layer (4” or greater) on top of existing concrete pavement.

Uses a “separation interlayer” to separate new overlay and existing concrete.

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Unbonded Overlays Separation Interlayer: “Key” Overlay Old Pavement Smooth Slip Plane Overlay Old Pavement Interlayer (1 in)

I-69 UNBONDED PCC OVERLAY PCCP over old Concrete Pavement

Conventional Whitetopping Consists of thick concrete layer (4 in or greater) on top of an existing asphalt pavement. Behaves as a new pavement on a strong base.

Typical Whitetopping Thickness Depends on expected traffic load. – City streets, county roads, and small airports 4 to 7 in. – Primary roads and interstate highways 7 to 11 in. – Large airports 8 to 18 in.

Harding Street - Indianapolis Built in 1985 6” Overlay on old HMA pavement 8” thick on stone where widened Skewed Joints

PCCP over old Chip & seal road 121 st St., Fishers

Allisonville Road PCCP over 2 lane HMA street

Allisonville Road Cross Section

UTW Schematic Short Square Slabs (2 to 6 ft.) Thin Slabs (2 to 4 inches) Milled Surface

Market & Columbia Streets - Warsaw 3.5” PCCP over HMA, Gravel, & Brick

Demonstration in 2002

Photo by Indiana Public Works.com Magazine

Warsaw Whitetop October 2002 July 2005

Concrete Roads and Streets

Concrete Intersections & Roundabouts US 31 & SR 32 US 6 & US 421 Pontiac Ave. & Wayne Trace, Ft. Wayne Gray Rd. & 96 th St.

96 th St. approaching Keystone Ave.

Pervious Concrete

Summary KNOW YOUR OPTIONS

Questions?

Contact: Jerry L. Larson (317) 634-8989 [email protected]

Indiana Ready Mixed Concrete Association (317) 872-6302 www.irmca.com

INDIANA CHAPTER