SETTLEMENT OF BUILDINGS ON SATURATED SAND DURING EARTHQUAKES

Abstract

Shaking table tests were conducted on models of rigid structures placed on saturated sand in order to study the pore pressure development in the sand near the structure and to study the factors which influenced the settlement of the structure. The settlement records of reinforced concrete buildings during the Niigata earthquake of 1964 were reviewed for comparison with the model test results.The studies showed : (1) The excess pore pressure developed below the center of the model structure was smaller than that away from the structure. (2) The ratio of the excess pore pressure to the initial effective stress below the center of the model structure decreased as the structure became heavier. (3) For both the model and the prototype the settlement of the structure decreased as the width of the structure increased for a given depth of liquefaction. (4) A pair of rigid walls embedded on both sides of the model structure had a considerable effect on reducing the excess pore pressure below the structure and a marked effect on reducing the settlement of the structure.