454 In lieu of using hand chipping tools or handheld mechanically driven equipment, a milling machine may be used. If a milling machine is used it shall be one that does not damage the adjacent pavement. If reinforcing bars are encountered during the removal operation, the patch shall be changed to a full depth patch in ac cordance with 506.08(b). Wire mesh reinforcement exposed during the removal operations shall be removed. If concrete is exposed below 1/3 of the thickness of the existing pavement, the patch shall be changed to a full depth patch in accordance with 506.08(b). 390 Partial depth cavities shall be thoroughly sandblasted and, just prior to placing new concrete, cleaned of all dust, chips, a nd water. The air lines for sandblasting and air cleaning shall be equipped with oil trap s to prevent contamination of the surfaces.
b.Full Depth Removal After the full depth saw cut is completed, vehicle mounted removal equipment may be used to remove the concrete pr ovided this equipment does not damage the adjacent sound concrete. 400 Removal areas in the same lane which are closer than 10 ft shall require the PCCP between these areas to be removed and replaced. If a transverse joint is located within the removal area, the limits of removal shall be as shown on the plans. Full depth saw cutting and removal shall be extended at the direction of the Engineer until sound PCCP is encountered to allow the drilling and installation of dowel bars for load transfer. Removal operations shall not damage the existing PCCP that is sound and is to remain in place. Existing subbase shall be completely removed. Before removing any type of 410 asphalt treated, cement treated, or concrete subbase, the Contractor shall saw cut the outline of the removal area using a power -driven saw with a diamond blade. The Contractor shall cut the asphalt treated s ubbase at least 2 in. deep on a neat line perpendicular to the subbase surface. The Contractor shall cu t the cement treated subbase or concrete subbase full depth. 506.09 Concrete Mixing and Transportation
a.For Patches Less than or Equal to 15 ft in Length Concrete batching tolerances, mixing, and transportation shall be in accordance 420 with 502.10 and the following. Discharge from non-agitating equipment shall be completed within 30 minutes of mixing th e water, cement, aggregates, and calcium chloride solution. Discharge from a truck agitator or a truck mixer shall be completed within 90 minutes of mixing the water, cement, and aggregates or within 30 minutes of the addition of calcium chloride solution. If the location of the plant is such that this time limit cannot be met, the calcium chloride solution shall be added to the concrete 506.09 455 in a transit mixer at the site and the concrete shall then be mixed for an additional 40 revolutions prior to discharge.
1.Central Mixed Concrete 430 Central mixed concrete shall be in accordance with 502.10(a). 2. Shrink Mixed Concrete Shrink mixed concrete shall be in accordance with 502.10(b).
3.Transit Mixed Concrete Transit mixed concrete shall be in accordance with 502.10(c).
b.For Patches Greater than 15 ft in Length For patches containing portland cement, the mixing and transportation shall be in 440 accordance with 502.10. If concrete contai ning CSA cement is used, it may be batched and mixed in a mobile volumetric mixer meeting the requirements of 722.09, regardless of the patch length. Calibration of the mobile mixer shall be in accordance with 722.13. Alternatively, a mixer from a CSA cement supplier may be used, if approved by the Engineer.
506.10 Weather Limitations
PCCP patches shall not be placed on frozen subgrade, subbase, or PCCP. 506.11 Placing Concrete 450 The concrete shall be placed level to the adjacent PCCP and consolidated by internal vibration. The concrete shall be hand finished in accordance with 504. Texturing and tining are not required if the PCCP is to be resurfaced with HMA or diamond ground in accordance with 507.06. The PCCP patch shall be cured with liquid membrane forming curing compound in accordance with 504.04(a). In addition to applying liquid memb rane forming curing compound, if the ambient temperature is below 55°F at the time of placement, polyethylene film shall be placed over the pa tch and covered with a 4 in. layer of rigid or flexible insulation and firmly anchored. Otherwise, polyethylene film, insulation, 460 or any other covering shall not be used. Small dimension lumber weighted with sandbags may be used, but large objects such as rocks or concrete blocks shall not be used. Covering with polyethylene film or any other covering does not replace the requirement to use liquid membrane forming curing compound. The PCCP patch shall be inspected in accordance with 502.17. For patches which are not to be overlaid and have a length greater than 20 ft, 470 pavement smoothness will be in accordance with 501.25 except inertial profiler requirements will not apply. 506.11
a.Partial Depth A non-vapor barrier type bonding agent shall be applied to the vertical and horizontal surfaces prior to placing concrete. Coated surfaces shall be protected from contaminants such as dust and dirt. Cont aminated surfaces shall be recleaned and recoated. The bonding agent and concrete shall be placed in accordance with the bonding agent manufacturer’s recommendations. The recommended time limits will be strictly enforced. 480 Existing joint openings within the patch shall be maintained for the full depth of the patch by preformed joint fillers or forms. After the patch has cured, these joints shall be sawed and sealed in accordance with 503.
b.Full Depth Subgrade treatment and subbase shall be constructed as shown on the plans. Dowel bars shall be installed to provide load transfer from the adjoining PCCP to the patch. The diameter of the drilled holes shall be no more than 1/8 in. greater than 490 the diameter of the dowel bar. Dowel bars shall be placed parallel to the pavement surface and to the longitudinal joint. Dowel alignment tolerances shall be as shown on the plans. Dowel holes shall be drilled using hydraulic, electric, or pneumatic percussion drills without spalling or damaging the exis ting concrete. Drills shall be capable of independent adjustment of each drill shaft in the horizontal and vertical direction. The device used to drill dowel holes shall be slab-riding and be capable of drilling a minimum of three holes at a time. The drilled holes shall be free of dust, moisture, and grease prior to installation of the dowel bars. The chemical anchor system shall be 500 injected to the back of the hole to elimin ate air pockets prior to inserting the dowel bar. The quantity of material injected shall be sufficient to disperse the chemical anchor material along the entire length of the dowel bar and completely fill all voids around the bar. Application of the chemical anchor system by buttering it onto the dowel bar will not be allowed. After the anchor system has been injected, the dowel bar shall be fully inserted in the hole using a back-and-forth twisting motion, leaving the proper length exposed. If 510 it is necessary to use a hammer to seat the dowel bar, the exposed end shall be protected with a wood block. A lightweight plastic, clear or semi-transparent grout retention ring shall be installed after each dowel bar is inserted in to the hole. The grout retention ring shall be pushed flush to the vertical ly sawn concrete surface and shall be used to help retain the chemical anchor syst em in the dowel hole. 506.11 457 Retrofit tie bars shall be installed in accordance with 503 and as shown on the plans. The tolerance for horizontal and vertical translation shall be the same as for 520 dowel bars. Joint filler and grout retention rings shall be placed and installed at the pressure relief joint as shown on the plans. Oversized holes shall be drilled in the joint filler no more than 1/2 in. over the dowel bar diameter and at a spacing to match the installed dowel bars. The oversized holes are to allow a tolerance for ease of installation of the joint filler up against the sawed face without interference with the dowel bars. The joint filler shall be attach ed to the sawed face wit hout wrinkles or buckling. Joint filler material with vertical slits or cuts will be rejected. Grout retention discs 530 shall be installed to make the annular sp ace between the dowel and the oversized hole mortar-tight. The joint material may be spliced along vertical joints that are joined and sealed with tape. The joint material shall not be spliced in the horizontal direction. An alternate method of installing a joint filler that has a mortar tight seal around the dowel bar may be used if approved by the Engineer. All patches longer than 15 ft shall be placed in accordance with 502.12 and shall have joints in accordance with 503. Dowel bars shall be installed within the boundaries of the patch at a spacing as shown on the plans or as approved by the Engineer. Patches longer than 15 ft shall be finished in accordance with 504. Patches longer than 15 ft, constructed with concrete containing portland cement, shall be cured in accordance with 504.04(a) unless ambient air and concrete temperatures warrant following the requirements in 506.11. Patches constructed in accordance w ith 506.04(b) and containing CSA cement shall be water cured in accordance with 702. 22(a)1 except that soaker hoses will not be required. Water curing shall be initiated after finishing and as soon as the concrete patch can support the wet covering. Water curing shall be maintained for a minimum 550 of 1 1/2 h and shall be removed no sooner than 1 h before the patch is opened to traffic. Concrete shall be placed around manholes or similar structures in accordance with 720. Sawing and sealing of transverse joints may be omitted when the existing PCCP is to be overlaid as part of the contract. 506.12 Opening to Traffic For purposes of this section, traffic shall include construction vehicles, 560 construction equipment, and all non-construction vehicles. Any construction vehicle or equipment that may damage the PCCP shall not be used on the PCCP unless adequate protection is provided. Joint cutting saws may be operated on the PCCP as determined by the Contractor. 506.12
a.For Patches Less than or Equal to 15 ft in Length A patch may be opened to traffic in acco rdance with the following when calcium chloride is used in accordance with 506.04(a). T H HT T H HT 40 - 42°F 30 26 61 - 63°F 14 9 43 - 45°F 27 23 64 - 66°F 14 9 46 - 48°F 24 21 67 - 69°F 14 8 49 - 51°F 21 19 70 - 72°F 14 7 52 - 54°F 19 16 73 - 75°F 14 6 55 - 57°F 16 14 above 75°F 14 5 58 - 60°F 16 11 T = Lowest ambient temperature during placement, or the temperature of concrete at time of delivery, whichever is lower. H = Time in hours to open to traffic. HT = Time in hours to open to traffic when the average daily traffic is less than 10,000. PCCP patches with calcium chloride ma y be opened to traffic sooner than specified in the above table if test beams indicate a modulus of rupture of 300 psi or greater. ITM 402 may be used as an altern ative method to determine the flexural strength. When other admixtures or admixture systems are used, the PCCP patches may be opened to traffic when flexural strength tests indicate a modulus of rupture of 300 psi or greater. ITM 402 may be used as an alternate method to determine the flexural strength. 580
b.For Patches Greater than 15 ft in Length Traffic shall not be allowed on the PCCP until a modulus of rupture of 425 psi from flexural strength testi ng is achieved. The modulus of rupture will be determined by averaging two beams.
506.13 Method of Measurement
Partial depth patching and full depth patching will be measured by the square yard. D-1 contraction joints and retrofitted tie bars used in PCCP patching will be 590 measured in accordance with 503.07. When subgrade treatment is specified, it will be measured in accordance with
207.05 New subbase will be measured in accordance with 302.08. PCCP removal, subbase removal, conc rete, finishing, curing, and sawing and
sealing of joints will not be measured for payment. 506.13 Retrofit pressure relief joints, retrofit contraction joints, non-vapor barrier bonding agent, anchored dowel bars installed at the beginning and end of the patch, 600 individual dowel bars, joint fillers, joint materials, drilling holes for dowel bars, grout retention rings, and chemical anchor systems will not be measured for payment. 506.14 Basis of Payment PCCP patching will be paid for at the contract unit price per square yard for the type of patching required. D-1 contraction joints and retrofitted tie bars used in PCCP patching will be paid for in accordance with 503.08. 610 Subgrade treatment will be paid for in accordance with 207.06. New subbase will be paid for in accordance with 302.09. Partial depth patches which have been directed to be full depth will be paid for at the contract unit price per square yard for PCCP patching, partial depth, plus 80% of the contract unit price per square yard for PCCP patching, full depth. Payment will be made under: Pay Item Pay Unit Symbol 620 PCCP Patching, Full Depth ....................................................... SYS PCCP Patching, Partial Depth ................................................... SYS The cost of PCCP removal, subbase removal, concrete, finishing, curing, and sawing and sealing of joints shall be included in the cost of PCCP patching. The cost of retrofit pressure relief joints, retrofit contraction joints, non-vapor barrier bonding agent, anchored dowel bars installed at the beginning and end of the patch, individual dowel bars, joint fillers, joint materials, drilling holes for dowel bars, 630 grout retention rings, and chemical anchoring system shall be included in the cost of PCCP patching. The cost of corrections for pavement sm oothness and retexturing shall be included in the cost of PCCP patching. Repair or replacement of adjacent PC CP or shoulder damaged by the Contractor shall be made at no addition al cost to the Department. 640 506.14
Source: Indiana Standard Specifications, 2024 Edition. Pages 452–458 of 1,248.