CONCRETE PIPE Single Circular Cage Reinforcing cages are produced on automated cage welding machines to ensure tight tolerances for our engineered products. The amount of steel reinforcement is specified by ASTM standards or special designs. The type of reinforcement used depends on production processes and local availability. Reinforcement is provided to the pipe producer by steel companies under certified testing procedures. Double Circular Cage Single Elliptical Cage Combination Elliptical and Circular Cages Steel Reinforcement Welded Wire Fabric Welded wire fabric is prefabricated from high-strength, cold drawn wires and consists of longitudinal wires welded to transverse wires to form rectangular grids. Each wire intersection is electric resistance-welded by automatic welders. Smooth wires, deformed wires, or a combination of both may be used. Welded wire fabric is manufactured to ASTM Standard A 185 or A 497. The positive mechanical anchorage at each wire intersection of welded smooth wire fabric provides the concrete to steel bond characteristics. Welded deformed wire fabric utilizes wire deformations in addition to the welded intersections to improve bond characteristics. Cross-sectional area is the basic measure used in specifying wire sizes. Smooth wire sizes are identified by the letter W followed by a number indicating the crosssectional area of the wire in hundredths of a square inch. For example, W16 denotes a smooth wire with cross-sectional area of 103 mm2 (0.16 square inches). Similarly, deformed wire sizes are identified by the letter D followed by a number which also indicates the cross-sectional area in hundredths of a square inch. For example, D 10 is a deformed wire with a cross-sectional area of 64.5 mm2 (0.10 square inches). PAGE 16 LAFARGE PIPE eMANUAL