THE OBSERVATIONAL SYSTEM OF THREE COMPONENTIAL EARTH PRESSURE USING BORE HOLE

Abstract

  In order to estimate three componential earth pressure, we have developed an earth pressure cell and a penetration device. These developments were undertaken as part of the project for the build-up of information-based construction management system. This observational system uses boreholes effectively, and enables us to estimate the overall behavior and distribution of stresses within foundation soils. This system consists of two processes. The penetration device is lowered down into the ground to certain depth firstly, and then the earth pressure cell is penetrated horizontally into the cylindrical wall of the borehole. Three componential earth pressure within the ground can be made by changing the directions of the face of the cell. Comparison of the results of labolatory experiment with those of theoretical and analytical estimations demonstrates the utility of the system. This paper also introduces the case history of the tunnel construction in soft ground at Tokyo bay area.