Development of a 1-DoF Force Sensor with an Aluminum Cross-Beam Structure for Earth Pressure Measurement System

Abstract

This study focuses on development of a one degree of freedom force sensor with an earth pressure cell to identify the effective soil pressure and pore water pressure in a single degree of freedom sensor system. In order to detect earth pressure from 20 kN/m2–150 kN/m2, a strain gauge based four cross-beam metal structural element is used to match the civil engineering application. In order to achieve this requirement, novel pressure transferring mechanisms are developed which will transfer the earth loads to sensing elements via deformation of cross-beam structure as a total load and as an effective load. The optimum dimension for the sensor element was selected by using Finite element analysis and other dimensions and the shape of the sensor are selected by carrying out an in-depth literature survey. The sensor was developed using advanced precision machine tools which included CNC and EDM. Verification of the accuracy of the system will be done by using methods which are currently available for measuring soil pressure and pore water pressure under laboratory and field conditions.