2507Culvert Liner

2507.1DESCRIPTION

This Work consists of lining Culvert pipe by inserting a polyethylene (PE) liner inside an in-place Culvert.

2507.2MATERIALS

A Pipe Provide one of the following types of liner as shown on the Plans or specified in the Special provisions:

2507.3CONSTRUCTION REQUIREMENTS

A General The Department will specify the diameter or span of the in-place pipe to be lined in the Contract item. Follow liner dimensions as shown on the Plans and as specified by the Special Provisions. Use a liner and grout method that has adequate space between the in-place pipe and liner to grout the annular space. Use slings, boom-type trucks, or an equivalent approved by the Engineer to unload liners at the Project. Do not dump liners from the truck or use chains or wire rope for handling . The Contractor may use a winch truck or equivalent Equipment approved by the Engineer, to install the liner. The Department will consider any damaged liner to be unacceptable. Unacceptable liner includes but is not limited to liner that is damaged during handling or installation, or rejected because it does not meet Plan requirements. B Installing Liner B.1 General Inspect the interior of the in-place pipe to identify conditions which may prevent proper installation and to confirm that the liner and installation method proposed by the C ontractor are adequate for existing site conditions. Use jet rodding Equipment, hydro-mechanical methods or other methods approved by the Engineer to clean and dry the in-place pipe before inserting the liner. Remove or repair all obstructions that would prevent installation or damage the liner during installation. Remove debris or other Materials from the in-place pipe to prevent the inserted liner from resting on or against, or be irregularly supported by, these Materials. The Contractor may use a flange connector or a full encirclement with neoprene connects and stainless steel clamps to make final connection. Allow the liner to stabilize from 8 hours to 10 hours before tying the last joint or pressure grouting the annular space between the in-place Culvert and the inserted liner. Use fasteners, blocks, or multiple grout Layers to secure liners equal to or greater than 2 feet in diameter to the invert of the in-place pipe to prevent the liner from floating during the grouting operations. B.2 Inserting Liner The Contractor may pull or push pre-fused lengths of solid wall PE liner into place. The Contractor may combine the push and pull techniques to insert the liners.

B.2.a Pull Technique Use a cable or winch arrangement to pull the liner into place. Feed the cable from the winch through the in-place pipe. Fasten the cable to the liner to allow the liner to be pulled through the in-place pipe and into place. The Contractor may fabricate the pulling head out of a few extra feet of the liner by cutting out evenly spaced wedges from the leading edge, collapsing the fingers towards the center, and fastening the cable to the fingers. B.2.b Push Technique Place a choker strap around the liner outside the access point . Use a tractor mounted backhoe, backhoe, or an equivalent piece of Equipment approved by the Engineer to pull the choker, thus pushing the liner through the in- place pipe. Ensure that with each stroke of the backhoe, the choker grips the liner and pushes the leading edge of the liner further into the in-place Culvert. The Contractor may use a front-end loader or bulldozers to simultaneously push on the trailing end of the liner segment. B.3 Pipe Joints Use heat fusion or grooved press-on joints approved by the Engineer to join PE liner meeting requirements of ASTM F714 (DR 32.5), Standard Specification for Polyethylene (PE) Plastic Pipe (DR-PR) Based on Outside Diameter. Heat fuse liner joints as recommended by the liner manufacturer, using an experienced operator of the heat fusion E quipment. Use a threaded joint to join liner segments of closed-profile PE liner with an ASTM D3350, Standard Specification for Polyethylene Plastic Pipe and Fittings Material, cell classification of 345464C as approved by the Engineer. C Grout Block off Culvert ends before filling the annular space between the liner and the in- place pipe. Provide CLSM Low Density or CLSM High Density grout in accordance with 2519, “Cellular Concrete,” and as shown on the Plans or as required by the Contract. Use CLSM High Density grout if the Plans or the Contract do not specify the grout type. Do not allow grouting pressure to exceed the external hydrostatic collapse resistance of the liner. D Culvert Cleaning Clean sediment and debris from lined pipe before final acceptance.

2507.4METHOD OF MEASUREMENT

A Pipe Liner The Engineer will measure liner by length, as determined by summation of the N ominal laying lengths of the individual liner sections incorporated in each lined pipe . The Engineer will separately measure Culvert pipe liner by size, type, and kind in accordance with the Contract Items. The size is the diameter or span of the in-place pipe being lined. B Culvert Appurtenances The Engineer will separately measure aprons or other appurtenances required to the installation of the liner in accordance with 2501, “Pipe Culverts.” C Grout The Engineer will measure grout in accordance with 2519, “Cellular Concrete.”

2507.5BASIS OF PAYMENT

The Contract linear foot price for Lining culvert pipe will include the cost of excavating, cleaning, inserting the liner, backfilling, and providing liner, fittings, seals, and joint system . This cost includes cleaning and repair activities required to prepare the in-place pipe prior to inserting the liner and cleaning the lined pipe before final acceptance. The Department will pay for grouting with the Contract Unit Price for CLSM Low Density, or CLSM High Density, as shown on the Plans and in accordance with 2519 “Cellular Concrete.” The Department will pay for Culvert appurtenances in accordance with 2501, “Pipe Culverts.” The Department will pay for Lining Culvert pipe on the basis of the following schedule: Item No. Item Unit

2507.503 Lining Culvert Pipe ___” linear foot