Experimental Study on Influence of a Pile Penetration on Deformation of a Buried Pipe in Sand

Abstract

In this paper, influence of installation of new piles on an existing buried pipe was investigated through small-scale model tests. Close-ended aluminum pipes of 595 mm in length and 32.0 mm in outer diameter were used for the model piles in dry sand model ground. A close-ended PVC pipe of 700 mm in length and 18.0 mm in outer diameter was used as a buried pipe model. The PVC pipe was instrumented with axial strain gauges to obtain bending moments in vertical and horizontal directions. The PVC pipe was set in the model ground horizontally at a depth 230 mm. The model piles were pressed-in into the ground from the ground surface at locations near the buried pipe. The distributions of the buried pipe displacements in the vertical and horizontal directions were estimated using the measured bending moments. The experiments were carried out in dense (relative density Dr = 80%) and loose (Dr = 50%) sand grounds. The paper presents the experimental results, and discusses the influential factors, such as distance between the piles and the buried pipe, the pile tip level and soil density, on the deformation of the buried pipe.