Subaqueous Concrete Pipe with Flexible Joints
One of the most expensive features of laying a subaqueous pipe line is the employment of divers to make the pipe joints tight. The work of the diver, it is claimed, is reduced to a minimum by the use of a new type of subaqueous concrete pipe with expansion and flexible joints, the invention of Coleman Meriwether, which is being developed by the Meriwether Pressure Pipe Company. A number of sections of this pipe can be joined together on the beach or bank. Bulkheads are then placed on each end. The joined sections are launched and towed to the proper location and lowered by scows on each side with windlass on the scows and cables under the pipe at proper points. As will be seen by the illustration, the pipe is provided with expansion and flexible joints, the concrete portion being 16 feet long and the joint one foot long, making total length of pipe of 17 feet. Iron angles 2 1/2 x 2 1/2 x 1 1/4 inches—1/4-inch larger inside diameter than the outer diameter of the pipes— are placed on each end of pipe. Hardwood wedges closely spaced make the angles tight and truly concentric with the outer diameter of the pipes. For effluent pipe with the end open, 3/4 x 3 1/4-inch standard machine bolts, spaced approximately with 8-inch centers, 13/16-inch holes punched in angles coincide with the holes in the flexible joints in which the bolts are placed. For pressure pipe for inverted siphons or other uses the bolts are the same and spaced the same as for standard flange pipe.
The joint can be expanded 1 1/2 inches one side and contracted one inch on the other, so that, as can be seen, if the foundation of an inverted siphon should be undermined by a freshet, the elasticity of the joints would allow a very great deflection which would be taken up in a number of joints. Consequently, the siphon would remain watertight.