Design of the Rigid Dowel Pile for Landslide Control

Abstract

A cast-in-place pile of a diameter of 1.0m to 3. 5m is used as a rigid dowel pile for landslide control, but the method of design of such a pile is not yet established.The paper discusses the behavior of the rigid dowel pile used in the landslide area for increasing the shearing resistance at the sliding surface by the dowel force and also the method of design of such a pile .The basic concept of design is that when a soil mass slides over a sliding surface, the pile tilts to produce subgrade reaction in the soil mass above and below the sliding surface and thus a dowel force at the sliding surface. And it is intended to resolve the equilibrium conditions of the forces loaded on the pile, to calculate the bending moment, shearing force, tilt and subgrade reaction acting on the pile and thus to obtain the basic conditions for design of the pile. This method of analysis is applicable to multi-layered soils . From the result of measurement of the earth pressure on a large diameter pile constructed actually in a landslide area, said me thod of design of the pile is adequate. It is also shown that a method of determining the pile casting position at which the pile will exhibits the dowel force fully from a diagram of distribution of the horizontal internal force obtainable by slope stability analysis.