Liquefaction Behavior of Bushehr Coastal Carbonate Sand

Abstract

Over the past few years, liquefaction phenomena have always been one of the challenging issues in geotechnical engineering. The occurrence of liquefaction is due to cyclic tensions resulting from zero effective stress in the soil mass. Carbonate sands are significantly different in static and dynamic resistance than silicate sands. In this research, this phenomenon has been studied by studying the liquefaction behavior of Bushehr carbonate sand. In this paper, the liquefaction of Bushehr carbonate sand in multiple relative densities, different cyclic stress ratios (CSR), and different overburden stresses are studied and investigated. The liquefaction status of this sand is investigated in dry conditions and volume control situations in the simple shear apparatus. The results indicated that in the same conditions and a low cyclic stress ratio, by reducing overhead stress from 300 to 50 kPa, resistance to liquefaction in Bushehr carbonate sand will be 35 times more. This is not true in the higher cyclic stress ratio, in which liquefaction occurs in very low cycles (up to three cycles). The results also indicated that carbonate sand shows lower liquefaction resistance compared to silica sand.

Keywords

• carbonate sand
• liquefaction phenomena
• simple shear apparatus