Static and Dynamic Effects of the Pipe Insertion Machine Technique

A new method of in place sewer reconstruction called the Pipe Insertion Machine was field tested by the U.S. Army Construction Engineering Research Laboratory. The technology uses an impact mole to break up the existing pipe and force it into the surrounding soil as the new pipe is pushed into the space created by the impact mole. The field test monitored stress induced in an adjacent pipe, soil displacement, and vibrations. The results indicate that, under the site conditions of this test, the reconstruction method was successful and induced very little stress on the surrounding utilities. Vibrations may be a problem for certain structures in the immediate vicinity of the impact mole, but vibrations damp out quickly a short distance away. Keywords: Sewers; Replacement; Pipe insertion machine.