The stability of piles adjacent to a slurry-supported trench

The use of diaphragm walls in many deep excavation projects has become increasingly popular during the past three decades. Diaphragm walls are frequently constructed close to existing structures, and yet the understanding of the interaction between diaphragm wall installation and adjacent structures is very limited. An investigation of the installation effects of diaphragm walls adjacent to piled foundations has been undertaken by means of a series of small-scale model tests in the geotechnical centrifuge at Cambridge University. The research focused on the stability of piles adjacent to a slurry-supported trench in dry dense fine sand. This paper presents a description of the centrifuge model and the observations from a parametric study of the influence of reduction in slurry level on the pile and soil responses. The results suggest that pile stability increases as the length of the trench decreases or when it is at a larger offset distance away from the trench.