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specified. Cast iron manhole covers and assemblies shall be cast <br /> into slab tops for access into manholes. <br /> 2. Minimum compressive strength of concrete shall be 4000 psi and the <br /> maximum permissible absorption shall be 6.5%. Risers shall be <br /> reinforced with a single cage of steel placed within the center third of <br /> the wall. The tongue or the groove of the joint shall contain one line <br /> of circumferential reinforcement equal in area to that in the barrel of <br /> the manhole riser. The minimum cross-sectional area of steel per <br /> linear foot shall be 0.12 square inches for larger sizes. Precast <br /> manhole sections shall fit together readily and shall have a <br /> self-contained "O"-ring rubber gasket conforming to ASTM C443. <br /> 3. The quality of materials, the process of manufacture, and the <br /> finished manhole sections shall be subject to inspection and <br /> approval by the Engineer and his inspector. The manhole sections <br /> shall be perpendicular to their longitudinal axis, within the limits listed <br /> in ASTM C478. <br /> 4. Castings for manhole frames and covers shall be tough, even <br /> grained soft gray iron, free from burnt on sand and other injurious <br /> defects and conform to the requirements of ASTM A48, latest <br /> revision, Class 30, with "WATER" cast into the cover. <br /> 5. Brick for manholes and other structures shall conform to applicable <br /> requirements of ASTM C62, latest revision, Grade SW. <br /> F. Tapping Sleeve and Valve: <br /> 1. Tapping sleeves shall consist of two piece split ductile iron, jointed <br /> by bolts manufactured of high strength cast iron and incorporating a <br /> longitudinal compound rubber gasket. The sleeves shall include split <br /> end gasket and two piece mechanical joint glands suitable for the <br /> class of pipe around which sleeves are to be placed. Glands will be <br /> joined by steel bolts and fastened to the bell openings of the sleeves <br /> to form totally enclosed rubber water tight seals around the periphery <br /> of the pipe and along the longitudinal joints. <br /> 2. The sleeves shall have flanged outlets which will accommodate the <br /> tapping valves. Valves will be identical to resilient wedge gate <br /> valves elsewhere specified with inlet and outlet ends adaptable to <br /> the tapping machine and to provide mechanical joint connections to <br /> discharge pipes. <br /> Rev. 10/22/01 PROJECT#13.01126 02640-Page 6 <br />