Section 2310. Portland Cement Concrete Overlay
2310.01 description.
Overlay an existing pavement with a PCC overlay. Existing pavements may include any of the following:
B. Composite pavement (flexible pavement over PCC).
C. Pavement with a stress relief layer placed over the top.
D. Full depth flexible pavement.
2310.02 materials.
Meet the requirements of Article 2301.02.
1. Use Class C concrete for PCC Overlays as specified in Materials I.M. 529, except use a C-3WR or C-4WR mix design for Bonded Overlays. Allowable substitutions shall comply with Article 2301.02, B.
2. For coarse aggregate, meet the requirements of Section 4109.02, Aggregate Gradation Table, Gradation No. 3 or 5. Ensure the nominal maximum coarse aggregate size is no greater than one-third the overlay thickness.
3. Unless otherwise specified, use coarse aggregate for overlays over existing PCC pavement that is the same type of aggregate as the existing pavement. If existing pavement aggregate type cannot be determined or is not available, use limestone or dolomite coarse aggregate.
B. Hot Mix Asphalt Stress Relief Course.
1. When required by the contract documents, use an HMA stress relief course consisting of a nominal 1 inch course of HMA meeting the requirements of Section 2303.
2. Use PG 58-28S asphalt binder.
3. Use a mixture meeting the following:
a. Standard Traffic (ST), 3/8 inch HMA mix requirements.
b. Target air voids of 3.0%.
c. No maximum film thickness restriction and no minimum filler/bitumen ratio restriction.
d. Type B Aggregate (or better) with no percent crushed particle requirements and gradation falling below the restricted zone.
e. Apply Article 2303.05, A, 3, a, 2 for AAD Acceptance of lab voids.
1. Use white pigmented liquid curing compound meeting the requirements of Article 4105.05.
2. Use pavement interlayer geotextile meeting the requirements of Article 4196.01, B, 7.
D. Fiber Reinforcement.
1. When fiber reinforcement is specified in the contract documents, use product approved in accordance with Materials I.M. 491.27, Appendix B.
2. Dose fiber reinforcement at the rate of 4 pounds per cubic yard of concrete unless stated otherwise in the contract documents.
2310.03 construction.
Apply the requirements of Section 2301 to this work with the modifications identified below.
A. Scarifying, Shotblasting, or Waterblasting Equipment.
Use power operated equipment capable of uniformly scarifying or removing the existing surface in a satisfactory manner and to depths required. Other types of removal devices may be used if their operation is suitable and if they can be demonstrated to the satisfaction of the Engineer. The contract documents will include a pay item for such work.
1. General.
a. If full depth base repair is included in the project, complete it prior to preparation of the existing pavement surface.
b. When required, include the entire area to be resurfaced in preparation of the existing pavement surface. Materials removed in the preparation operation may be placed in the shoulder area unless specified otherwise in the contract documents.
2. Surface Preparation.
a. When required for overlays over existing PCC pavement, prepare the surface by shot blasting, waterblasting, or scarifying. Scarify to a nominal depth of 1/4 inch.
b. Ensure preparation removes all dirt, oil, foreign materials, laitance, or loose material from the surface and edges against which new concrete will be placed.
3. Pavement Scarification.
a. When required, prepare surface by scarifying per Section 2214.
b. At the direction of the Engineer, trim high spots found in the existing flexible pavement. This work will be accomplished during the scarification operation, only at isolated locations, and will be considered incidental to the pavement scarification.
c. Bond Breaker for PCC Patches.
For all existing PCC patches that have been scarified and all new PCC patches not previously coated with curing compound apply a bond breaker prior to placing the PCC overlay using one of the two methods below:
1) Prior to placement of
the PCC overlay, pPlace
two applications of liquid curing compound on
all scarified PCC patches or other PCC surfaces to be overlain.
Apply each coat evenly on the full area at a rate of 1 gallon per 200 square
feet. If drying to the touch occurs within 10 minutes or rapid absorption into
the scarified PCC surface is noted, then apply a third coat at a rate of 1
gallon per 200 square feet.
2) Place pavement interlayer geotextile in accordance with Article 2310.03, B, 5.
4. Hot Mix Asphalt Stress Relief Course.
Construct in accordance with Article 2303.03. Use Class II Compaction, except use only static steel wheeled rollers. Article 2303.04 shall also apply.
5. Pavement Interlayer Geotextile.
a. Sweep pavement to remove loose debris before applying pavement interlayer geotextile.
b. Place geotextile tight without excessive wrinkles or folds.
c. Use one of the following methods to secure the geotextile:
1) Secure geotextile with pins or nails punched through 2 to 2.75 inch galvanized washers or disks every 6 feet along the edges and at least every 6 feet across the width of the pavement in a grid pattern. Place additional fasteners as needed to ensure geotextile does not shift or fold during concrete placement.
2) Secure geotextile with 3M HoldFast 70 Cylinder Spray Adhesive or approved alternate. Apply to all edges of the fabric and as needed to prevent shifting or folding of the fabric during concrete placement.
3) Other anchoring methods approved the Engineer.
d. If geotextile fails to remain secured in place, resecure geotextile and limit placement length in advance of the paving machine such that proper securement can be maintained. Keep driving on geotextile to a minimum. Delay installation on areas subject to excess traffic, such as crossovers, until immediately before concrete placement.
e. Do not allow more than three layers of the geotextile to overlap in any location. Overlap edges of geotextile 8 inches ± 2 inches. Sequence rolling out geotextile to ensure good lapping practice and prevent folding or tearing by construction traffic.
f. Extend free edge of geotextile interlayer a minimum of 4 inches beyond edge of pavement. Terminate interlayer in a drainable layer. Do not impair free drainage within the geotextile.
g. Keep geotextile clean and free of loose debris before concrete placement.
C. Placing and Finishing Overlay.
1. General.
b. Ensure existing pavement surface is free of standing water during PCC placement.
c. Ensure temperature of existing pavement surface does not exceed 120ºF during PCC placement. Water may be applied to cool existing pavement surface provided standing water is not present during PCC placement.
d. Introduce fiber reinforcement into the mix in accordance with the fiber manufacturer’s recommendations, unless otherwise approved by the Engineer. Ensure uniform distribution and random orientation of fibers throughout the concrete.
2. Joints.
a. Saw joints as shown in the contract documents. Seal all joints unless directed otherwise.
b. For overlays over existing PCC pavements:
1) Place joints directly over joints and cracks in the existing pavement.
2) Saw joints to the full depth of the overlay.
3) Ensure joints are at least as wide as the joint or crack in the existing pavement.
D. Limitation of Operations.
1. At forecasted air temperatures below 55°F use the maturity method to determine the opening time. Do not place resurfacing concrete when the air or pavement temperature is below 40°F.
2. The Contractor may use the shoulders for construction activities. It will be the Contractor's responsibility to repair the shoulders, as the Engineer deems necessary, to restore the shoulders to a condition acceptable for shoulder work. This work shall be done at no additional cost to the Contracting Authority. The Contractor may elect to limit the use and vehicle loadings to minimize this work and its cost.
3. Place concrete overlays over existing PCC pavements between June 1 and September 30.
E. Time for Opening Pavement for Use.
1. The time for opening pavement for use shall be in accordance with Article 2301.03, U.
2. When the maturity method for opening is utilized, the Engineer may allow an opening strength requirement of 350 psi, for overlays 6 inches or greater.
F. Smoothness.
Apply Section 2317.
2310.04 method of measurement.
A. Portland Cement Concrete Overlay, Furnish Only.
Cubic yards using a count of batches incorporated. Includes concrete placed in widening sections and partial depth patches.
B. Portland Cement Concrete Overlay, Placement Only.
Square yards shown in the contract documents. Area will be determined from the longitudinal surface and the nominal pavement width, including widening sections.
Square yards shown in the contract documents. Area will be determined from the longitudinal surface and the nominal width of existing pavement.
1. Measurement by Weight.
The quantity of Pavement Scarification will be determined in accordance with Article 2214.04, A, 1.
2. Measurement by Area.
The quantity of Pavement Scarification will be determined in accordance with Article 2214.04, A, 2.
E. Hot Mix Asphalt Stress Relief Course.
1. Measurement by Weight.
a. HMA will be measured according to Article 2303.04, A.
b. Asphalt binder will be measured according to Article 2303.04, B.
2. Measurement by Area.
a. HMA will be measured according to Article 2303,04, A, 2.
b. Asphalt binder used will not be measured separately for payment.
F.
Seal Coat Bond Breaker for PCC Patches.
The quantity of bond breaker for PCC patches will be the quantity in square yards shown in the contract documents.
1.
Aggregate.
Cover aggregate will be measured according to Article 2307.04, A.
2.
Binder
Bitumen.
Binder Bitumen will be measured according to Article 2307.04, B.
G. Pavement Interlayer Geotextile.
The quantity of Pavement Interlayer Geotextile will be the quantity in square yards shown in the contract documents.
H.
G. Fiber Reinforcement.
Fiber reinforcement will be measured in pounds of fiber incorporated
into the concrete mix.
2310.05 basis of payment.
A. Portland Cement Concrete Overlay, Furnish Only.
1. Per cubic yard.
2. Payment is full compensation for furnishing raw materials, proportioning, mixing, and delivery of concrete to the paving machine.
B. Portland Cement Concrete Overlay, Placement Only.
1. Per square yard.
2. Payment is full compensation for:
a. Furnishing all materials, labor, and equipment necessary to place, finish, texture, and cure the concrete.
b. Placement of tie bars for widening, if required.
c. Sawing, cleaning, and sealing the joints, if required.
d. Surface cleaning.
1. Per square yard.
2. Payment is full compensation for preparation of the existing pavement, scarifying or shot blasting, and for removal of the existing pavement surface material according to Article 1104.08.
1. Measurement by Weight.
The Contractor will be paid the contract unit price for Pavement Scarification in accordance with Article 2214.05, A, 1.
2. Measurement by Area.
The Contractor will be paid the contract unit price for Pavement Scarification in accordance with Article 2214.05, A, 2.
E. Hot Mix Asphalt Stress Relief Course.
1. Measurement by Weight.
a. Article 2303.05 applies.
b. Payment is full compensation for furnishing and placing the HMA stress relief course.
c. Asphalt binder will be paid for separately according to Article 2303.05, B.
2. Measurement by Area.
a. Article 2303.05 applies.
b. Payment is full compensation for furnishing and placing the HMA stress relief course, including the cost of the asphalt binder.
F.
Seal Coat Bond Breaker for PCC Patches.
Payment for bond breaker for PCC patches will be at the contract unit price per square yard. Payment is full compensation for furnishing materials, labor and equipment necessary to install the bond breaker for PCC patches.
1. Aggregate.
Payment for cover aggregate will
be in accordance with Article 2307.05, A.
2. Binder Bitumen.
Payment for binder bitumen will be
in accordance with Article 2307.05, B.
G. Pavement Interlayer Geotextile.
Payment for Pavement Interlayer Geotextile will be at the contract unit price per square yard. Payment is full compensation for furnishing materials, labor and equipment necessary to install the pavement interlayer geotextile.
H.
G. Fiber Reinforcement.
Per pound of fiber reinforcing. Payment shall will
be full compensation for supplying all materials, equipment, and labor for
incorporating fiber reinforcement into the concrete mix.