768 When finally accepted, all structures shall be free from any accumulation of silt, debris, or other foreign matter. 140 The Contractor may precast inlets, catch basins, or manholes, subject to approval. If precast concrete inlets, catch basins, or manholes are used, a layer of structure backfill of minimum thickness of 4 in. shall be used under each unit for ease in positioning. If holes are formed or field cut in precast inlets or catch basins to receive the pipe structures, the pipes shall be conn ected directly to the precast unit, by means of a class A concrete collar of a minimum longitudinal and radial thickness of 6 in. Holes formed or cut in the wrong place shall be plugged satisfactorily with a class A concrete mixture. 150 Horizontal joints may be used in the construction of precast catch basins. A sketch of the type, location, and sealing material planned for each joint shall be submitted for approval. No joints shall be closer than 3 in. above standing water for those catch basins requiring hoods. Grade and location adjustments to precast inlets and catch basins caused by unforeseen conditions shall be handled as if the units were being cast-in-place. All additional adjustments required due to precasti ng will not be paid for directly, but the cost thereof shall be included in the cost of the inlet or catch basin.
720.04 Grade Adjustment of Existing Structures
When grade adjustment of existing structures is specified, the frames, covers, and gratings shall be removed and the walls rec onstructed as required. The cleaned frames shall be reset at the required elevation. If so specified or if it is determined that the existing casting and supporting walls are in good condition, an approved device may be used to adjust the manhole casting cover to the correct grade without reconstructing the walls or resetting the frame. Upon completion, each structure shall be cleaned of any accumulations of silt, debris, or foreign matter of any kind and shall be kept clear of such accumulation until 170 final acceptance of the work. Excavation and backfill shall be done in accordance with 720.03. If an existing casting is unfit for further use, a new casting shall be furnished with payment at the contract unit price per each for castings of the type specified, furnished, and adjusted to grade. This payment sh all include and be full compensation for furnishing the new casting, placing and adju sting it to grade, including any necessary removal, construction, or reconstruction of not to exceed 12 in. average height of the upper portion of the masonry. 180 When manholes, catch basins and inlets are adjusted to grade and are to abut existing concrete construction, the castings shall be entirely separated from the adjacent concrete by a preformed expansion jo int no less than 3/8 in. in thickness. The 720.04 769 cost of furnishing and placing the preformed expansion joint material will not be paid for directly, but shall be included in the payment for reconstructed catch basin, or reconstructed inlet, or castings furnished and adjusted to grade. The preformed expansion joint material shall be in accordance with 906.01. On resurface contracts the castings shall, unless otherwise directed, be adjusted to 190 grade after the last binder course has been laid and before placing the surface course.
720.05 Capping Existing Structures
All structures directed to be capped shall be as shown on the plans or by filling the structure with class A concrete after the existing drainage has been maintained. The flow of water through pipes or underdrains in structures shall be perpetuated. Alternate methods for capping shall be submitted for approval before they may be used.
720.06 Method of Measurement 200
Manholes, inlets, spring boxes, and catch basins, both new and reconstructed as applicable, will be measured per each unit, complete in place. Castings adjusted to grade and castings furnished and adjusted to grade will be measured per each unit complete in place, if the average adjustment height does not exceed 12 in. If corrections to the stru cture involve portions exceeding an average adjustment height of 12 in., the additional work will be measured by the linear foot for the type of structure involved. The capping of existing structures will be measured by the number of structures 210 capped. 720.07 Basis of Payment The accepted quantities of manholes, inlets , spring boxes, catch basins, castings adjusted to grade not exceeding 12 in., and castings furnished and adjusted to grade not exceeding 12 in. will be paid for at the contract unit price per each, complete in place. That portion of a reconstructed structur e which exceeds 12 in. in average height will be paid for at the contract unit price per linear foot, for structure, of the type 220 specified, reconstruct, complete in place. The capping of inlets and other structures will be paid for at the contract unit price per each for cap inlet. Payment will be made under: Pay Item Pay Unit Symbol Casting, ____, Adjust to Grade ................................................. EACH 230 type 720.07 770 Casting, ____, Furnish and Adjust to Grade .............................. EACH type Catch Basin, ____ ...................................................................... EACH type Inlet, ____ .................................................................................. EACH type Inlet, Cap ................................................................................... EACH Inlet, type H, with Slotted Drains .............................................. EACH Inlet, type HA, with Slotted Drains ........................................... EACH 240 Manhole, ____ ........................................................................... EACH type Pipe Catch Basin, ____ in. ........................................................ EACH size Spring Box ................................................................................. EACH Structure, ____, Reconstructed .................................................. LFT type The cost of both inlets, the 12 in. pipe connecting the two inlets, the Type 5 castings, the concrete filler between the barrier wall and the inlet, and other 250 miscellaneous materials shall be included in the cost of the inlet, Type H. The cost of the inlet, the Type 5 casting, the concrete filler between the barrier wall and the inlet, and other miscellaneous materials shall be included in the cost of the inlet, Type HA. The cost of both inlets, the 12 in. pipe connecting the two inlets, the Type 5 castings, the concrete filler between the barrier wall and the inlets, the slotted drain pipe, the concrete collar around the slo tted drain pipe, and other miscellaneous materials shall be included in the cost of the inlet, Type H, with slotted drains. The cost of the inlet, the Type 5 casting, the concrete filler between the barrier wall and the inlet, the slotted drain pipe, the concrete collar around the slotted drain pipe, and other 260 miscellaneous materials shall be included in the cost of the inlet, Type HA, with slotted drains. The cost of excavation, backfill, reinforcing bars, structure backfill, concrete collar required for pipe connection to structures, removal, disposal and replacement of pavement, or surface material, casting removal, installation of concrete cap, HMA wedge, damage repair to pavement and shoul ders, and necessary incidentals shall be included in the cost of the pay items. 270 720.07