Published by department of transportation
-3.06–60-3.10 RESERVED 60-4 MODIFYING STRUCTURES 60-4.01 GENERAL
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- 60-4.02 REFINISHING BRIDGE DECKS
- 60-4.02C(2) Placing Portland Cement Concrete
- 60-4.02C(3) Placing Rapid Setting Concrete
- 60-4.03B Materials Rapid-setting concrete must comply with section 60-3.02B(2). 60-4.03C Construction
- 60-4.03C(2) Deck Access Openings
- 60-4.03C(4) Soffit Access Opening Extensions
- 60-4.03C(5) Close Deck Access Openings
60-3.06–60-3.10 RESERVED60-4 MODIFYING STRUCTURES 60-4.01 GENERAL60-4.01A GeneralSection 60-4 includes specifications for modifying structures. 60-4.01B MaterialsNot Used 60-4.01C ConstructionNot Used 60-4.01D PaymentNot Used 60-4.02 REFINISHING BRIDGE DECKS60-4.02A GeneralSection 60-4.02 includes specifications for refinishing bridge decks. The Engineer determines the exact area to be refinished. 60-4.02B MaterialsConcrete for refinishing bridge decks must be either portland cement concrete or rapid setting concrete. Portland cement concrete must comply with section 90-1 and the following: 1. Concrete must contain at least 675 pounds of cementitious material per cubic yard. 2. Free water must not exceed 280 lb/cu yd. 3. Aggregate must contain from 50 to 55 percent fine aggregate. The remaining portion must be pea gravel. Grade pea gravel such that 100 percent passes the 1/2-inch sieve and at most 5 percent passes the no. 16 sieve. 4. Engineer may request that admixtures be used. Rapid setting concrete must comply with section 60-3.02. Epoxy adhesive must comply with the specifications for epoxy adhesive for bonding freshly mixed concrete to hardened concrete. 60-4.02C Construction60-4.02C(1) GeneralFor removal work performed within 10 feet of a traffic lane or over a traffic lane, remove the dust and residue using an authorized vacuum, a water spray, or a shield method. Make a 3/4-inch-deep saw cut around the perimeter of the deck to be refinished. Remove concrete in areas to be refinished to a depth of approximately 3/4 inch. Do not damage concrete to remain in place. Prepare existing deck areas more than 3/4 inch below adjoining deck surfaces by removing at least 1/4 inch of surface material to expose sound aggregate. Remove concrete by abrasive blast cutting, abrasive sawing, impact tool cutting, machine rotary abrading, or other methods. Removal methods must be authorized. Clean prepared areas of dust and loose and deleterious materials by brooming, abrasive blast cleaning, and using high-pressure air. Re-blast contaminated areas before starting concrete placement activities. Protect existing reinforcement exposed during concrete removal. Cut off dowels 1 inch below the existing deck surface or at the bottom of concrete removal, whichever is lower. Where refinishing is not required, cut dowels off 1 inch below the finished surface. Patch holes with rapid setting concrete complying with section 60-3.02. You may refinish isolated high areas by cutting the concrete down flush with adjoining deck surfaces. Use abrasive sawing, grinding, impact tool cutting, or other authorized methods. Fill prepared areas flush with the plane of the adjoining deck using concrete. Transversely score fresh concrete surfaces. Use a stiff-bristled broom or other suitable device. Completed surfaces must have a uniform texture with a coefficient of friction of at least 0.35 when tested under California Test 342. Grind or groove surfaces having a coefficient of friction less than 0.35 under section 42. Refinished surfaces must (1) be flush with the adjoining surface and (2) not vary more than 0.02 foot from the lower edge of a 12-foot straightedge placed in the longitudinal direction.
Apply an epoxy adhesive to cleaned surfaces immediately after cleaning. Surfaces must be dry and have a temperature of at least 40 degrees F when applying the adhesive. The Engineer determines the application rate. Place concrete on fresh epoxy adhesive. Consolidate concrete immediately after placement until voids are filled and free mortar appears on the surface. Strike off concrete to the required grade. Cure concrete under section 51-1.03H. Do not apply loads of any type to the concrete until at least 7 days after placement.
Do not allow traffic on concrete until 24 hours after final set unless authorized. 60-4.02D PaymentThe payment quantity for refinish bridge deck is the sum of (1) the area measured along the surface and (2) 0.2 square foot for patching around each dowel. The Department does not adjust the unit price for an increase or decrease in the refinish bridge deck quantity. 60-4.03 ACCESS OPENINGS60-4.03A GeneralSection 60-4.03 includes specifications for constructing access openings and closing access openings when access is no longer required. Reinforcement must comply with section 52. Steel plates, hardware, and thread-locking compound must comply with section 75-3.
60-4.03B MaterialsRapid-setting concrete must comply with section 60-3.02B(2). 60-4.03C Construction60-4.03C(1) GeneralRemoving portions of bridges must comply with section 60-2. Limits of removal shown are approximate. The Engineer must authorize removal limits before you start removal activities. Paint exposed ends of the remaining reinforcement with 2 coats of organic zinc-rich coating as specified for exposed ends of prestressing steel in section 50-1.03B(3)(a). Within cells where work activities are performed, remove existing formwork and concrete that interfere with the work. In cells that adjoin hinges, bent caps, or abutments, remove existing forms and sharp projections in the cell between the adjoined element and 5 feet past the access opening.
60-4.03C(3) Soffit Access OpeningsRemove portions of the existing soffit, including the bar reinforcing steel, at the locations shown. Seal the access openings with access doors when cell access is no longer required. 60-4.03C(4) Soffit Access Opening ExtensionsFor bridge soffit access opening extensions, remove and replace concrete to the limits shown. You may reduce removal limits if authorized. Reconstruct and seal soffit access openings to the original dimensions when cell access is no longer required. Use concrete or rapid-setting concrete to reconstruct the access openings. Placing concrete must comply with section 51. Placing rapid-setting concrete must comply with section 60-3.02C(6).
Use water to flush dust from areas to be filled with concrete. Remove all water by air blasting before placing concrete. Do not allow traffic on the new concrete until at least 1 hour after final set unless authorized. If the close deck access opening work has not been completed, use temporary deck cover plates to temporarily close the deck access openings before opening the lane to traffic. Temporary deck cover plates must remain in place until the deck access opening is permanently closed.
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