The Effect of Underground Short Piles with High Rigidity on Shear Stress and Displacement along Ground Failure Surface

Abstract

This paper presents an idea of a new method to improve stability of geo structures against shear failures due to service loads, seismic loads, heavy rainfalls, etc. In this method, a series of short piles, like steel bars or sheet piles, are pressed-in to the depth of the failure surface, which is considered to have the lowest safety factor in the design process And they are left underground by decoupling from the rod used for press-in process. As the piles are arranged only around the failure surface, the total amount of piles is much smaller resulting in cost effective improvement of stability of the geo structures. In this study, the effects of the underground short piles are examined by simple models of under ground section along the failure surface, using dry silica sand and rigid steel piles. The models were sheared under a direct shear condition with constant surcharge, and their shear stress and displacement, as well as the rotation of the short piles, were observed.