THE SIZE EFFECTS OF EARTH PRESSURE CELLS ON MEASUREMENT IN GRANULAR MATERIALS

KINYA MIURA, NATSUHIKO OTSUKA, EEIJI KOHAMA, CHAIRAT SUPACHAWAROTE and GOH HIRABAYASHI

ABSTRACT: This paper aims to reveal the size effect of earth pressure cells on measurements in sand and gravels and propose a guideline for the selection of an appropriate size. In the case of gravel containing large particles, point loadings at several contact points in the cell make it difficult to measure the earth pressure with sufficient accuracy and reliability. Four types of earth pressure cells were used in this study with different sizes of sensitive panels and principles of measurements. A series of loading tests were conducted with sand and four types of gravels. The reliability of the test results was first examined; the influence of parameters such as the stiffness of the earth pressure cell, and the sidewall friction of the test container were investigated. From a comparative study of the measured data, the appropriate size of the earth pressure cell was determined as a function of the grain size of the gravel and accuracy needed in the measurements.

Key words: earth pressure cell, grain size, granular materials, laboratory test, loading test, size effect (IGC: D0/C7/C8)