Laserfiche WebLink
SEC"TION 02610 <br />RESTRAINED JOINTS, EXCAVATION AND BACKFILLING <br />GENERAL <br />Restrained Joints <br />Restrained joints shall be used on lines larger than 6 -inch diameter. Sections of piping having <br />restrained joints or those requiring restrained joints shall be constructed using pipe and fittings <br />with restrained "Locked -type" joints, and the joints shall be capable of holding against withdrawal <br />for line pressures up to 150 pounds per square inch (psi). The pipe fittings shall be as shown for <br />restrained push -on joints or restrained mechanical joints on 'age 416 in Section VI, in the <br />Handbook of Cast Iron Pipe, 4 l Edition. in all cases, restrained joints must be used per Section C <br />below, with thrust blocks, per contract drawings. <br />Restrained pipe joints that achieve restraint by incorporating cutout sections installed in the bell of <br />the pipe shall have a minimum wall thickness at the point of cutout that corresponds with the <br />minimum specified wall thickness for the rest of the pipe. <br />The minimum number of restrained joints required for resisting forces at fittings and changes in <br />direction of pipe shall be determined from the length of restrained pipe on each side of fittings and <br />changes in direction necessary to develop adequate resisting friction with the soil. Table M-513 is <br />provided for the Contractor as a guideline. <br />Table M -5B <br />1.5PA1-C- OS X) <br />fW <br />Where: L = Length of pipe on each side of fittings or change in direction <br />P = 150 psi, unless otherwise noted <br />A = Cross-sectional area in square inches based on outside diameter <br />(O.D.) of pipe <br />X = Angle of bend or change in direction in degrees <br />f = Coefficient of friction = 1.4 (maximum) <br />W = W (earth) + W (pipe) + W (water in pipe) W (earth) <br />= (density of soil*) (depth of cover in feet) (O.D. in feet) <br />Maximum 120-lbs/cubic ft above maximurn water table elevation <br />and 60-lbs/cubic ft below maximum water table elevation. <br />Bolts and nuts for restrained joints shall be hot dipped galvanized, low alloy, high strength steel. <br />The Contractor shall also provide restrained joints in accordance with the above criteria wherever <br />below ground fittings on lines 12 inches in diameter or less. <br />02610-1 <br />D:VVISION 2102810 Restrained Joints Excavation and Backfilling. doc <br />