introduCtion Jacking and Tunnel Pipe Lafarge can produce concrete pipe in a variety of sizes for trenchless installation with the jacking or tunneling methods.  The pipe sections are designed for the additional axial force encountered in these operations and can be produced with ports for grout or lubrication.   Trenchless installation of pipe is often used to minimize surface disruption, often under existing infrastructure such as railways and roadways. Concrete pipe is frequently installed by tunneling and jacking where deep installations are necessary or where conventional open excavation and backfill methods may not be feasible. Concrete pipelines were first jacked in place by the Northern Pacific Railroad between 1896 and 1900. In more recent years, this technique has been applied to sewer construction with intermediate shafts along the line of the sewer as jacking stations. The feasibility and planning of tunneling and jacking projects should be coordinated with local concrete pipe manufacturers and jacking contractors. Reinforced concrete pipe as small as 450 mm (18-inch) diameter and as large as 3300 mm (132-inch) diameter have been installed by jacking. Since conventional jacking procedures require access by workmen through the pipe to the heading, 900 mm (36-inch) diameter pipe is generally the smallest practical size for most jacking operations. When jacking smaller size pipe, earth removal is accomplished by mechanical means such as augers and boring equipment. Concrete pipe is ideally suited for tunneling and jacking. The pipe can be pushed forward immediately after the soil is excavated, providing a completed tunnel liner for protection of workers and equipment. Because of technological advances and increased experience, many pipelines are now being jacked. ConCrete pipe stormwater treatment teChnologies box seCtions manhole and CatCh basin material LAFARGE PIPE eMANUAL PAGE 41