Liquefaction Potensial Evaluation Based on Critical State Parameter Concept and Piezocone Test Of Sandy Sediments Padang Indonesia

Liquefaction is a process of change in the condition of a water-saturated sandy soil into a liquid, due to increased pore water pressure (pore water pressure) caused by dynamic loads that are generally associated with earthquake. Research activity is intended to find the relationship between variations in soil density sand with the possibility of liquefaction. The more dense sand soil liquefaction potential, the possibility of getting smaller. This study uses varying density to determine the potential for liquefaction with Triaxial Test and Test Piezocone. This modeling using sand Padang with varying density and the test performed of Triaxial CU to obtain a graph of the effective stress vs void ratio, the graph obtained from a critical state conditions in order to obtain potential areas of liquefaction. And the results of modeling sand soil samples with multiple density test Piezocone then analyzed using the method of Shibata Teparaksa Based with the value of the maximum seismic acceleration at the surface of 0,25g and 7.9 Richter scale earthquake. This method can determine the liquefaction potential or not. Modeling results obtained from the relationship that the sandy soil density is proportional to the value of the tip resistance and security factors.