Rev. 7-1-95
PREFORMED LOOP DETECTORS
805-T-038
The Standard Specifications are revised as follows:
SECTION 805, AFTER LINE 331, INSERT AS FOLLOWS:
805.09.1 Preformed Loop Detectors. Preformed loops shall be as shown on the plans, and shall be either commercially available or built by the Contractor. Three turns of 1c/14 loop wire, in accordance with 913.15(f)4f, shall be encased in a 19 mm (3/4 in.) diameter schedule 40 PVC pipe, with heavy wall construction. No splices will be permitted in the loop wire. One corner of the loop shall be terminated with a 19 mm (3/4 in.) diameter PVC tee fitting to provide an exit for the twisted lead-in cable. The preformed loops shall be sealed at all PVC pipe joints and at the tee with a rubber sealant to provide a watertight joint. The corners of the preformed loop excluding the tee shall consist of two 45E bends with 150 mm (6 in.) of straight 19 mm (3/4 in.) diameter PVC pipe between the bends. The bends shall have a smooth radius of 115 mm (42 in.) to the center of the PVC pipe. Standard PVC fittings and sleeves shall be used at all joints. No butt joints will be permitted. The preformed loops shall be placed in a 35 mm wide x 64 mm deep (1 3/8 in. wide x 22 in.) deep saw-cut trench as shown on the plans and backfilled with a sealer to the roadway surface. The sealer shall be in accordance with 913.15(f)4e(3). The PVC pipe shall continue all the way from the loop to the detector housing. SECTION 805, AFTER LINE 476, INSERT AS FOLLOWS:
Preformed Loop Detectors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .m (LFT)