In all jointing operations, the trench must be dewatered when joints are made and kept dewatered until sufficient time has elapsed to assure efficient hardening of the jointing material. Bell and spigots or tongue and groove ends of the pipe shall first be wiped clean before actual jointing operations are started. The type of joint to be installed in each location of the several following types specified shall be as specifically designated in the project specifications.
(a) Cement, Mortar and Jute Joints. Joints between consecutive pipes shall be made with jute and Portland cement mortar composed of one part Portland cement and two parts of fine aggregate. Fine aggregate shall be clean, graded, torpedo sand, free from any foreign matter.
Where pipe is being laid in wet sand or in other locations where it is considered by the Engineer to be necessary, the contractor shall use one-third natural cement and two-thirds Portland cement in lieu of 100 percent Portland cement in preparing the joint mortar.
Jute shall be of the best quality tarred manilla yarn and of a size to fit the details of the pipe joint.
One bell and spigot pipe or variations thereof, plastic mortar shall be spread in the bottom one-third of the bell of the pipe previously laid. A closely twisted gasket of jute of proper thickness and of sufficient length to span around the pipe and lap at the top shall then be squeezed into the mortar. The spigot of the next pipe shall then be entered and shoved home. After the pipe has been thoroughly bedded to line and grade, the jute gasket shall be caulked into the annular space with a suitable caulking tool in such manner as to seal the joint against leakage. The remainder of the space shall be completely filled with plastic mortar beveled off with the outside of the pipe. The joint in pipes thirty inches or larger in diameter shall also be pointed and smoothed from the inside after the pipe has been laid.
On pipe sewers of the tongue and groove type, the jointing material, plastic, mortar and jute, shall be placed on the edges of the upper half of the tongue of the pipe to be laid and the lower half of the socket of the pipe previously laid, the pipe then aligned, forced home and graded. Sufficient mortar shall be placed on each pipe so that the space between the two pipes shall tend to become filled by the sliding action of the beveled surfaces of the adjacent tongue and socket when the pipe is forced into place. Jute shall then be caulked in both the entire inside and top three-quarters of the outside of the joint recesses, wherever sufficient space within the joint recesses permits. A thin edged caulking tool or trowel shall be used for this purpose. All voids in both the inside and outside shall be completely filled with mortar and the inside shall be troweled smoothly. The finished joint shall not be greater than one inch in width.
Where deemed advisable by the owner, calcium chloride, in an amount not to exceed ten percent of cement, shall be added to the mortar used for jointing purposes at no additional compensation.
(b) Bituminous Joints, Mastic Type. Joints between consecutive pipes shall be made with jute and a bituminous pipe joint compound. Jute shall be as hereinafter specified for cement joints. The bituminous joint filler shall be made from asphalt, liquefiers, mineral fillers and fibers and shall be free from moisture. The filler shall be such that it shall have positive adhesion to pipe surfaces and shall be water, acid, and alkali-resistant. It shall be plastic and workable with a trowel and of a composition which will not result in a plastic flow of the material at temperatures up to eighty degrees Fahrenheit.
The filler shall be applied with a trowel to the annular spaces of the bell of the socket and spigot of the pipes and the joints shall be made up in the manner hereinbefore specified for cement joints.
(c) Bituminous Joints, Poured Type. Joints between consecutive bell and spigot pipe shall be made with dry jute and a bituminous jointing compound, poured into place. The bituminous compound shall be such that it will flow freely at 250 degrees Fahrenheit, with a melting point of not less than 200 degrees Fahrenheit, and shall harden to a consistency that will not result in a plastic flow at eighty degrees Fahrenheit.
The bell and spigot of pipes to be jointed together shall first be painted with a bituminous prime coat to insure adherence of the poured filler to the sides of the pipe. With pipe at grade and butted, the dry jute shall be caulked into position in such a manner as to leave a uniform space all around. The joint shall be made in one pour.
(d) Die Cast Tapered Type. Joints shall be consecutive bell and spigot pipe and shall be made by fitting the sewer pipe with an approved die-cast tapered-type joint, which shall be made by fitting the spigot and socket of the pipe with collars of a bituminous compound having a melting point of 240-270 degrees Fahrenheit and a penetration of four to seven at seventy-seven degrees Fahrenheit.
A line or ring of the bituminous compound shall be die-cast into the socket of the pipe and around the spigot of the pipe, of such size and dimension that, when the spigot is shoved firmly into the socket portion of the pipe, care must be taken not to distort such bituminous linings and rings. All pipe shall be dry and clean when lining and collars are cast. No pipe shall be used if either the collar or lining shows any void or unfilled space.
When laying the pipes, the lining and collar shall first be painted with a bituminous solvent, which shall cause their surfaces to become plastic or sticky, and when the pipes are shoved firmly together, the joint material shall unite and, incidental to diffusion of the solvent, congeal and become one homogenous body.
(e) Rubber or Special Composition Joints. Rubber or neoprene or similar special composition joints may be used in tongue and groove-type and bell and spigot-type pipe joints. The gaskets shall consist of a special ring in the bell and/or on the spigot according to the manufacturer’s design, fabricated out of a special composition or rubber specifically designed to resist the hardening action of the sulphur compound in sewage and to prevent disintegration from sewage or water over long periods.
Bituminous and rubber gasket jointing material and joints shall be made up in strict conformance with the manufacturer’s recommendations and directions.
If the type of rubber joint material furnished requires an application of rubber cement, bituminous or other coating to insure a water-tight joint, this coating material shall be furnished and applied.
The type of joint and jointing materials proposed to be used by the contractor, together with reference on a similar installation, shall be submitted to the Engineer for approval. No sewer shall be laid or installed until approval of the joint and jointing materials has been received from the Engineer
(Ord. 352. Passed 10-22-62.)