709.01 Description. This item shall consist of furnishing and
installing hot dipped galvanized steel conduit of t he size and at the locations shown on the plans and according to these specifications, or as directed. This item covers galvanized steel conduit installed above and below ground. This item shall also inclu de any flexible runs to light supports; straps and bolts for attach ment to poles, bridges, or other structures; fittings for connecti on to junction boxes, controller cabinets, and other elements of the comp lete installation, as required; and expansion devices.
709.02 Materials. All conduit, expansion joints, and fittings
shall be hot dipped galvanized, inside and outside, according to AASHTO M 111. Conduit shall be free of all imperfe ctions that might injure the cable. Conduit fittings and acces sories shall be suitable for underground, encased, and exposed appl ications according to Underwriters Laboratories and the late st National Electric Code. All conduit shall comply with UL Sp ecification UL-
6.Conduit straps shall be galvanized stock, sized according to size conduit shown on plans. Nuts on conduit strap anch or studs shall be galvanized and shall be of a locking type. Where a flexible conduit connection is required, al l metal flexible galvanized steel tubing with a liquid tight neopren e jacket extruded over the flexible metal core shall be used. The fi ttings required for connection between the flexible conduit and rigid c onduit or connection boxes shall be liquid tight and as recom mended by the manufacturer of the flexible conduit. Factory fabr icated flexible conduit assemblies having liquid tight characterist ics are acceptable. Non-watertight conduit is not acceptable. A flexib le conduit connection is required at the location of all bridg e expansion joints.
709.03 Construction Requirements. Underground conduit shall
be installed in trenches or predrilled tunnels not less than 12" (300 mm) below final grade except where otherwise i ndicated on the plans or directed. Trench excavation, backfill, co mpaction, and disposal of surplus material shall be performed to the satisfaction of the Engineer. Compaction shall be accomplished to the extent necessary to prevent future settlement of the trenc h. Disturbed surfaces shall be returned to their original condit ion. Conduit with fittings and appurtenances may be atta ched to bottoms of slabs on bridges; faces of wingwalls, co lumns, or bent caps; or flanges and webs of steel beams. Such att achment shall be achieved by use of conduit straps spaced at interva ls of 5' (1.5 m) and held in place by self-drilling anchors, expansi on shield anchors, or clamps on steel flanges. All conduit shall be reamed after threading to remo ve all burrs. Conduit shall be brushed thoroughly with a bristle brush before installation to remove all dirt from the inside sur face. At the time of installation, each threaded end of conduit shall be coated with an acceptable sealant to form watertight joints. All coupling connections shall be made so that the reamed ends o f conduit butt squarely against each other inside the coupling. C onduit ends at boxes shall be fitted with threadless bushings. Standard bends shall be used wherever possible, but when a conduit bend is formed, the largest possible bendin g radius shall be used and shall not be less than 6 times the nominal diameter of the conduit. Upon completion of each conduit run, a device havin g a diameter of at least 85% of the nominal diameter of the cond uit shall be pulled through the conduit run. If the device does not pull through, the cause of the obstruction shall be determined an d corrected. A ¼" (6 mm) nylon pull rope shall be pulled through e ach conduit and left in place for later use if the conduit is to be left empty.
709.04 Method of Measurement. Galvanized Steel Conduit will
be measured by the linear foot (meter) measured alo ng the axis of the conduit in its final position. It will not be considered complete until backfill and compaction have been satisfactor ily performed. All necessary conduit fittings will be included as part of the conduit run and will not be measured separately.
709.05 Basis of Payment. Work completed and accepted and
measured as provided above will be paid for at the contract unit price bid per linear foot (meter) for Galvanized St eel Conduit of the size specified, which price shall be full compensat ion for furnishing and installing conduit, fittings, and drag rope; fo r jacking, drilling, excavation, backfill, compaction, removal of surplu s material, and replacement of existing surfaces; and for all mater ials, labor, equipment, tools, and incidentals necessary to comp lete the work. Payment will be made under: Pay Item Pay Unit Galvanized Steel Conduit (__") (___mm) Linear Foot (Meter)
Source: , Edition.