forward and reverse motion. The machine shall be equipped with at least two finishing devices. The first finishing device shall be a vibrating mechanism, such as a vibrating pan, for consolidating the deposited mix. The vibrating pan shall be metal and of sufficient dimensions to ensure proper consolidation. The second finishing device 510 shall be either a rotating cylindrical drum, at least 45 in. in length, or a vibrating oscillating metal faced screed of 4 in. minimum in width. The vertical position of the finishing devices shall be positively controlled and the devices shall be raised clear of the finished surface when the machine is operated in the reverse direction. The vibration frequency of any vibrating finishing device shall be variable, with positive control between 3,000 and 6,000 vibrations per minute. Alternate finishing machines may be considered for approval subject to a written request. Screed rails and construction dams shall be separated from the newly finished overlay by passing a pointing trowel along the rail-to-overlay and dam-to-overlay 520 interfaces after the overlay has sufficiently set such that it does not flow back. This trowel cut shall be made for the entire length and depth of the rail or dam. The rails may be removed any time after the overlay ha s initially set. Adequate precautions shall be taken during and after the rail removal to protect the edge of the new overlay from damage. Protection shall be provided to prevent rapid drying of concrete. The rate of water evaporation shall be determined both prior to placement based on forecasted conditions and during placement based on actual conditions in accordance with ACI 308, section 5.2.1 or the following equation: 530 E = (T c2.5 - rT a2.5)(1 + 0.4V) x 10-6 where: E = Evaporation rate, lb/sq ft/h T c = Concrete mix temperature, °F Ta = Ambient temperature, °F r = (Percent of Relative Humidity)/100 V = Wind velocity, mph. Measurement of T a, r, and V shall be obtained from readings made by the local weather bureau or the Contractor's measur ements made on site. Measurement of T c shall be determined from the concrete on site at the point of placement. Fog misting shall be performed after the finishing operation and prior to the wet cure, where the evaporation rate exceeds or is expected to exceed 0.05 lb/sq ft/h. Fog misting shall 540 keep the environment above the concrete su rface at high humidity to protect against plastic shrinkage cracks and shall not be used to apply water directly to the surface to facilitate finishing. Evaporation retardants shall not be substituted for fog misting where the evaporation rate exceeds 0.05 lb/sq ft/h. 722.10 784 An evaporation retardant shall be applie d in a fine mist immediately after the finishing is complete to ensure that the surface remains wet until covered. The evaporation retardant shall be used as such and not as a finishing aid. These products consist primarily of water and excessive amounts of evaporation retardant shall not be applied and the product shall not be worked into the overlay surface. Evaporation 550 retardant shall only be used on SFMC overlay s. Evaporation retardant shall not be used in any other applications.
722.11 Texturing
The overlay surface shall be textured with a double thickness burlap drag or a minimum 4 ft wide turf dr ag immediately following th e placement of the overlay material. Areas where the texture is disturbed by other finishing operations shall be immediately restored to a burlap drag finish. Grooving or tining in the plastic concrete of the concrete overlay will not be 560 allowed. Longitudinal grooving shall not commence until the curing requirements have been met in accordance with 722.12. Grooves shall be cut into the hardened concrete surfaces parallel to the centerlin e using a mechanical cutting device. For curved bridges, grooves shall be cut along the curve chord within the spans. Grooving shall be done before traffic is allowed on the surface except as follows. The Contractor shall have the option of cutting the longitudinal grooves at the end of each phase of construction or waiting until all phases have been completed. If the Contractor elects to delay the grooving process until completion of all phases, the concrete overlay surface for any phase opened to traffic shall receive an interim coarse 570 broom finish during placement. The completion of the grooving process shall be within 30 days of completion of the last phase of construction. Any additional maintenance of traffic operations required for the grooving process shall be included in the cost of Maintaining Traffic. The interim broom finish shall not be allo wed as a surface texture when opened to traffic over a winter season. If the coarse broom texture is present and the Contractor is not in a position to finish all phases of the project, longitudinal grooving shall be placed into the hardened concrete in order to establish an acceptable driving surface texture for the winter season. 580 Each groove shall be 1/8 in. ±1/64 in. in width, 3/16 in. ±1/16 in. in depth. The grooves shall be uniformly spaced at 3/4 in. intervals measured from the center of groove to center of groove. Grooving shall not be within the area approximately 2 ft adjacent to the curbs or railings. The grooving shall not be cut closer than 3 in. nor further than 6 in. from any construction joint running parallel to the grooving. The grooving shall not be cut within 6 in. of deck drains, curbs, or expansion joints. If the bridge has a variable width traffic lane, the grooving shall remain parallel to the centerline of the main roadway. Any staggering of the groove terminations to accommodate the variable width shall be with in the shoulders. Stair stepped ends in 590 grooving will be allowed for skewed bridge decks. When a new reinforced concrete 722.11 785 approach slab is placed adjacent to the overlay, the grooving shall extend across the reinforced concrete approach slab. Grooving shall terminate approximately 6 in. from the interface with th e roadway pavement. The grooving machine shall contain diamond blades mounted on a multi-blade arbor on a self-propelled machine built for grooving hardened concrete surfaces. The grooving machine shall have a depth control device that detects variations in the deck surface and adjusts the cutting head height to maintain a specified depth of the grooves. The grooving machine shall have a guide device to control multi-pass alignment. 600 The Contractor shall submit a wastewater control and disposal plan for approval seven days prior to commencing grooving ac tivities. The wastewater control and disposal plan shall detail how all wastewater generated by the grooving activities shall be contained, tested for pH, stored and transported to a disposal facility in accordance with 202. Cleaning of the grooving debris and slurry shall be performed with a vacuum system equipped with fugitive dust control devices and be capable of removing wet debris and water in the same pass. The vacuum equipment shall be capable of washing 610 the deck with pressurized water during the vacuum operation to dislodge all debris and slurry from the bridge deck surface. Debris and slurry shall not be allowed to dry prior to vacuuming. 722.12 Curing When fly ash is used, the requirement for additional wet or dry curing time shall be determined based on the relative initial, and final time of set and a comparison of strength versus age using control concrete strengths at conventional cure period ages as the reference. The additional curing requirements shall be as approved by the Engineer. 620 For LMC overlays the minimum curing period shall be 48 h of wet cure followed by 48 h of dry cure. An LMC overlaid bridge deck may be opened to traffic during the dry curing duration when the compressive strength of cylinders is 4,000 psi or greater. For SFMC overlays the minimum curing period shall be seven calendar days consisting of 120 h of wet cure followed by 48 h dry cure. The deck shall remain completely covered during the dry cure period. An SFMC overlaid bridge deck may be opened to traffic after the dry cure period when the compressive strength of cylinders is 4,500 psi or greater. 630 For LMC-VE concrete overlays the minimum curing period shall be 3 h of wet cure. An LMC-VE overlaid bridge deck may be opened to traffic after the wet curing period when the compressive strength of cylinders is a minimum of 2,500 psi. The wet cure period for all overlay types is not controlled by strength and shall not be reduced. Membrane forming curing compound shall not be used to cure the 722.12 786 bridge deck overlay. All cylinders shall be 6 in. by 12 in. and compressive strength shall be determined from the average of a minimum of two cylinders. For LMC and SFMC, cylinders shall be cast and cured in accordance with 702.24. For LMC-VE 640 cylinders shall be cast and field cured at the jobsite under the same conditions as the LMC-VE overlay. The plastic film which forms on the surf ace of the overlay shall be protected from shrinkage cracking with a single layer of well drained wet burlap. This layer of wet burlap shall be placed as soon as the ove rlay surface will support it without deformation. The entire surface shall be covered with plastic sheeting and maintained in a saturated wet condition during the wet cure period. A network of soaker hoses shall be used under the plastic sheeting during the wet cure period for LMC and silica fume overlays. 650 When the ambient temperature falls below 50°F during either the wet or dry curing periods, the time that the temperature is below 50°F shall not be considered as part of the total curing period. When there is sufficient rain to wet the surface of the overlay for 1 h or more during the dry cure period, this number of hours shall not be considered as part of the dry cure period. Immediately upon the start of the dry cure period or opening to traffic, the surface shall be checked for cracks. Upon request, the Contractor shall flood the deck with water to facilitate inspectio n for cracks and distress. Where cracks exist, a thorough 660 investigation will be conducted prior to sealing cracks. Cores may be required to determine the actual crack depth. Surface crac ks not exceeding 3/8 in. in depth shall be sealed with a PCC Sealer/Healer followed by an application of an approved sand. Cracks exceeding 3/8 in. in depth shall not be sealed at this time. Corrective procedures for repairing cracks exceeding 3/8 in. in depth will be determined after further investigation which may include additional cores. The Department’s Division of Materials and Tests will be contacted and the Engineer will determine the method of repair including possible removal. Where the area of shallow cracking exceeds 5% of the deck area, then the method 670 of repair shall be the same as for cracks exceeding 3/8 in. The shallow crack area will be calculated by multiplying the total combined linear feet of all cracks less than 3/8 in. deep by a tributary width of 1 lft. The percentage of deck area will be the shallow crack area divided by the total deck area and multiplied by 100. Where it is determined by sounding or coring that adequate bonding between the overlay and the bridge deck has not been attained, the deficient areas shall be removed and replaced as directed.
722.13 Calibration of Continuous Mixers 680
a.Frequency A complete calibration shall be performed for each mixer prior to each pour unless 722.13 787 the initial calibration was made within the previous 10 calendar days. A mixer that has been calibrated within the previous 10 calendar days may be approved for use providing that the mixer operator is in possession of the completed, signed, certified, and dated Department calibration form for that mixer. A complete calibration of a mixer may be required at any time as dir ected. All mixers which are calibrated within the 10-day limit but are changing aggregate sources shall have an aggregate blend test performed. 690
b.Equipment All special equipment required for calibration shall be furnished. It shall include but not be limited to suitable material containers, buckets, stop watches, and a scale accurate to within 0.1 lb or 0.3% of the te st load, whichever is greater, at any point within the range of use. The minimum capacity of the scale shall be 150 lb. The scale shall be verified annually per ITM 910. The Contractor shall provide paperwork that shows the date the scale was verified by a company with NIST traceable class F weights. Samples shall be obtained and handled by the Contractor. Normal testing equipment such as aggregate sieves and containers shall also be furnished. 700
c.Pre-calibration The aggregate bin shall be clean and the bin vibrators shall be in good working order. The mixer shall be equipped with a grounding strap. The cement meter feeder, the fins, and all pockets shall be clean and free of any accumulated cement. The aeration system shall be equipped with a gauge or indicator to verify that the system is operating. The main belts and the latex strainer shall be clean and free of any accumulated material.
d.Calibration 710 1 . C e m e n t M e t e r The mixer manufacturer’s mix setting chart shall determine the specified operating revolutions per minute and the approximate number of counts required on the cement meter to deliver 94 lb of cement. At least 3,760 lb of cement shall be placed in the cement bin. The mixing unit shall rest on a level surface. The engine throttle shall be adjusted to obtain the required revolutions per minute. The unit discharging the cement shall be operated until the belt has made one complete revolution. The unit shall then be 720 stopped and the cement meter shall be reset to zero. A suitable container shall be positioned to catch the cement and at least 90 lb of cement shall be discharged. The time requi red to discharge the cement shall be measured with a stopwatch, the number of counts on the cement meter shall be recorded, and the weight of the discharged cement shall be determined. This process shall be repeated a total of three times. The cement counter shall be reset to zero before each repetition. 722.13 788 The following formulas shall be used to calculate the number of counts per 94 lb 730 of cement and the time required to discharge 94 lb of cement. Counts per 94 lb of cement = 94 ÷ A B Time in seconds per 94 lb of cement = 94 ÷ A C where: A = Total weight of cement in pounds for three trials B = Total number of counts on the cement meter for three trials C = Total time in seconds for three trials.
2.Water Flow Meter The accuracy of the water flow meter shall be verified by adjusting the flow to 2 gal. per minute. With the equipment operating at the required revolutions per minute, the water discharged during a 1-minute interval shall be collected and weighed. The weight in pounds of the discharged water shall be divided by 8.33 to determine the number of gallons. This procedure shall be repeated with the flow meter adjusted to 3 gal. per minute. 3. Aggregate Bin Gates The aggregate gate openings shall be adjusted to provide the required amount of 750 aggregate to produce a cubic yard of the designated mix. The gate settings for the fine aggregate and coarse aggregate shall be de termined separately. Each aggregate shall be verified by stopping the cement discharge and collecting the aggregate discharged in a container. Calculations for all aggregates shall be based on SSD weights taken from the mix design. The calculations shall be adjusted for the tested moisture content. The final gate setting for each aggregate shall dispense material within a tolerance of ±2% of the target weights after adjustment for measured moisture content. 760
4.Latex Throttling Valve The latex strainer shall be unobstructe d. The latex throttling valve shall be adjusted to deliver the required amount of latex emulsion admixture for each 94 lb of cement. With the unit operating at the required revolutions per minute for the calculated time in seconds per 94 lb of cement, the latex shall be discharged into a container. The weight of the latex shall be determined and, when necessary, the valve shall be adjusted such that the amount of latex discharged is within 1/2 lb of the amount required for each 94 lb of cement. One ve rification shall be performed to check the accuracy of the valve setting. 770
5.Admixture Dispensers This equipment shall be calibrated in accordance with the manufacturer’s instructions for the specific materials and quantities involved. 722.13 789 722.14 Patching an Existing Bridge Deck Overlay
a.Materials Materials shall be in accordance with 722.03. (b) Storage and Handling of Materials 780 Storage and handling of materials sh all be in accordance with 722.04.
c.Proportioning Proportioning shall be in accordance with 722.05. (d) Preparation of the Bridge Floor Preparation of the bridge floor shall be in accordance with the applicable provisions of 722.06.
e.Patching 790 Patching shall be in accordance with 722. 07 except as modified herein. Areas repaired by full depth patching shall not be open to traffic until the test beams indicate a minimum modulus of rupture of 550 psi.
f.Mixing Mixing shall be in accordance with the applicable provisions of 722.09. (g) Placing and Finishing Placing and finishing shall be in accordan ce with the applicable provisions of
722.10 Machine finishing shall be required when directed. 800
h.Texturing The surface texturing shall match the pattern of the adjacent overlay and shall be in accordance with the following: Immediately after the finishing is co mplete and before the surface film has formed, the surface of the overlay patch shall be textured by grooving in the same direction as the existing overlay. The grooves may be formed by mechanized equipment using a vibrating beam roller, a series of discs, or other approved device. Manual tools such as fluted floats, spring steel tined rakes, or finned floats with a 810 single row of fins may be used. The grooves shall be relatively uniform, smooth, and shall be formed without tearing the surface or bringing coarse aggregate to the top. The grooves shall be in accordance with 504.03. The grooves shall be terminated the same distance from the vertical faces of railings as the existing grooves in the adjacent existing overlay surface. All areas of hardened grooved overlay patching which do not conform to these requirements, due to either a deficiency in the grooving or a rough open textured surface, shall be corrected with no additional payment. Corrections shall be made by cutting grooves in the hardened overlay with an approved cutting machine or by 820 722.14 790 sealing with an approved mixture and retexturing to a satisfactory finish as directed.
i.Curing Curing shall be in accordance with 722. 12 when patching has been performed using overlay concrete. Patches that have b een constructed using bridge deck patching concrete shall be wet cured until test beams indicate a minimum modulus of rupture of 550 psi. Patches that have been constructed using rapid setting patch materials shall be cured in accordance with the manufacturer’s recommendations.
j.Calibration of Continuous Mixers 830 Calibration shall be in accordance with 722.13. 722.15 Method of Measurement Removal of the existing overlay and the additional depth into the existing deck surface will be measured by the square yard of deck area regardless of the number of passes with the milling machine. Removal of the existing concrete deck surface will be measured by the square yard for the initial depth shown on the plans. Additional surface removal required below the initial depth will be measured by the square yard for each required 1/4 in. 840 depth. The areas of the bridge floor which are shown on the plans to be removed, except for undefined full depth patching areas, will not be measured for payment. Hydrodemolition of the bridge deck will be measured by the square yard. Additional surface preparation around reinforcing bars will be measured by the linear foot of exposed reinforcing bar. Reinforcing bar repair will not be measured for payment. When hydrodemolition is not shown on the plans, partial depth patching will be measured by the square foot. 850 The measurement of bridge deck patching concrete for partial depth cavities created by handchipping or hydrodemolition will be based on a theoretical quantity determined by multiplying the area of the appropriate partial depth cavities by an assumed average depth of 2 in. and converting the resulting volume into cubic yards. Overlay material used in a partial depth cavity will be measured by the cubic yard. The quantities of patching material used in a partial depth cavity will be included in the measurement of additional bridge deck overlay. The overlay and bridge deck patching concrete used to fill cavities as part of 860 patching an existing bridge deck overlay will not be measured for payment. Overlay material used to fill surface irregularities and partial depth cavities will be calculated by the cubic yard and will be included for payment for Bridge Deck Overlay Budget. 722.15 791 Full depth patching will be measured by the square foot. The patching material used in full depth patching will not be measured for payment. Bridge deck overlay will be measured by the square yard for the specified 870 thickness. Where there is no specified thickness shown on the plans, the specified thickness shall be 2 in. Overlay dams and patching an existing overlay will be measured by the square foot. Longitudinal grooving will be measured by the square yard. No deduction in measurement will be made for areas where grooving is terminated or not required. Epoxy resin adhesive and bond coat will not be measured for payment. Blasting, 880 cleaning, finishing, texturing other than the longitudinal grooving, and curing will not be measured for payment. 722.16 Basis of Payment Removal of the existing overlay and the additional depth into the existing deck surface will be paid for at the contract unit price per square yard of bridge deck, remove existing concrete overlay. Milling of the initial depth of surface will be paid for at the contract unit price per square yard of bridge deck, remove existing concrete surface. Additional surface 890 removal below the initial depth will be paid for at the contract unit price per square yard for bridge deck, remove existing concrete surface for each required 1/4 in. depth. Hydrodemolition of the bridge deck will be paid for at the contract unit price per square yard. When hydrodemolition is shown on the plans, additional surface preparation will be paid for at the established price shown per linear foot for bridge deck overlay, additional surface prep. When hydrodemolition is not shown on the plans, partia l depth patching will be paid for at the contract unit price per square foot for bridge deck patching, partial 900 depth. When partial depth cavities are subsequently directed to be made full depth, additional payment will be made at 80% of the contract unit price per square foot for bridge deck patching, full depth. Full depth patching will be paid for at the contract unit price per square foot for bridge deck patching, full depth. Bridge deck overlay will be paid for at the contract unit price per square yard, for 910 the type of overlay material specified. 722.16 792 Patching an existing bridge deck overlay will be paid for at the contract unit price per square foot for bridge deck overlay patching. Overlay dam will be paid for at the contract unit price per square foot, complete in place. Longitudinal grooving will be paid for at the contract unit price per square yard. 920 The Department will include the pay ite m Bridge Deck Overlay Budget, with an established dollar amount in the proposal to pay for additional surface preparation completed after hydrodemolition and bridge deck overlay additional quantity used to fill irregularities and partial depth cavities. The Bridge Deck Overlay Budget amount shown in the proposal is included in the to tal bid amount. The Depa rtment will pay for the additional quantity installed to fill irregularities and partial depth cavities as directed by the Engineer. Where the material exceeds the planned overlay quantity, payment will be at the invoice cost of the additional bridge deck overlay quantity installed. An amount equal to 10% of the in voice cost will also be paid for additional disposal and all other related costs in conn ection with the additional quantity installed. 930 No additional markup shall be applied for additional bridge deck overlay quantity installed. This amount will be paid using the Bridge Deck Overlay Budget pay item. Payment will be made under: Pay Item Pay Unit Symbol Bridge Deck Overlay Budget .................................................... DOL Bridge Deck Overlay, Latex Modified ...................................... SYS Bridge Deck Overlay, LMC-VE ................................................ SYS 940 Bridge Deck Overlay, Patching ................................................. SFT Bridge Deck Overlay, Silica Fume Modified ............................ SYS Bridge Deck, Remove Existing Concrete Overlay .................... SYS Bridge Deck, Remove Existing Concrete Surface ..................... SYS Bridge Deck Patching, Full Depth ............................................. SFT Bridge Deck Patching, Partial Depth ......................................... SFT Hydrodemolition ....................................................................... SYS Longitudinal Grooving .............................................................. SYS Overlay Dam ............................................................................. SFT Item shown with an established price will be paid at the price shown. Pay Item Pay Unit Established Symbol Price Bridge Deck Overlay, Addi tional Surface Prep...... LFT ............... $20 The cost of overlay removal by handchipping in areas adjacent to the curb or 722.16 793 otherwise inaccessible to the power-operat ed mechanical milling machine shall be included in the cost of bridge deck overlay, remove existing overlay. The cost of 960 disposing of overlay removal residue, includi ng water, dust, concrete and incidentals shall be included in the cost of bridge deck, remove existing overlay. The cost of deck surface preparation by ha ndchipping in areas ad jacent to the curb or otherwise inaccessible to the power-oper ated mechanical milling machine shall be included in the cost of bridge deck, remove existing concrete surface or bridge deck, remove existing overlay. The removal of surface milling residue, including water, dust, concrete, and incidentals shall be included in the cost of bridge deck, remove existing concrete surface or bridge deck, remove existing overlay. 970 The cost of the wastewater control and disposal plan, wastewater containment, testing, storing, transporting and disposal, and any incidentals related to the carrying out of the plan shall be included in the co st of hydrodemolition. If the wastewater is found to have a pH of 12.5 or higher and thereby classified as hazardous, the additional costs associated with this classification will be paid for in accordance with 109.05. The initial equipment calibration, any re-calibration, equipment shielding, handchipping curb areas, handchipping unsound concrete, cleaning of debris and slurry, compressed air cleaning, water blasting, and sandblasting shall be included in the cost of hydrodemolition. 980 When hydrodemolition is shown on the plans, the cost of removal of unsound concrete shall be included in the cost of hydrodemolition. Preparation of cavity surfaces, furnishing and applying bond coat or epoxy resin adhesive as required in handchipped locations, furnishing and pl acing patching material, and necessary incidentals shall be included in the cost of bridge deck overlay for the type of overlay material specified. Additional concrete re moval required around exposed bars shall be included in the cost of additional surface preparation. When hydrodemolition is not shown on the plans, the cost of removal of unsound 990 concrete, preparation of cavity surfaces, furnishing and applying bond coat or epoxy resin adhesive as required, furnishing and placing patchi ng material, and necessary incidentals shall be included in the cost of bridge deck patching, full depth, or bridge deck patching, partial depth. The cost of patching material used for full depth patching shall be included in the cost of bridge deck patching, full depth. The cost of texturing patched areas will not be paid for separately but shall be included in the cost of the patch. The cost of furnishing and placing patching material in partial depth cavities and 1000 necessary incidentals shall be included in the cost of bridge deck overlay, additional. When the project does not include the installation of a new bridge deck overlay, the cost of partial depth patching below the bottom of the overlay shall be included in 722.16 794 the cost of bridge deck overlay, patching. The cost of patching and overlay materials used to fill the cavities shall be included in the cost of bridge deck overlay, patching. The cost of removing existing concrete, furnishing, hauling, and placing all materials including the epoxy, preparing the surface, and all necessary incidentals shall be included in the cost of overlay dam. 1010 The cost of deck cleaning shall be included in the cost of other pay items. The cost of removing and disposing of the slurry created during the longitudinal grooving shall be included in the cost of longitudinal grooving. Coring of the bridge deck, patching core holes, and all corrective measures required in accordance with 722.12 shall be performed at no additional cost to the Department.
Source: Indiana Standard Specifications, 2024 Edition. Pages 797–809 of 1,248.