Liquefaction Characteristics of Sandy Soil Distributed in Wind Power Farms, Soc Trang Province, Vietnam

Wind power has been widely utilized and has become a safe and renewable energy source in many countries. In Vietnam, many wind power farms have been built in coastal provinces such as Soc Trang, Bac Lieu, Ninh Thuan, Binh Thuan, Ca Mau, Vung Tau, and the Central Highlands. For onshore wind power farms, the dynamic loads generated from wind and the operation of the turbine will act on soil ground and affect the long-term strength and liquefaction potential of soil, especially for sandy soil. Thus, it is necessary to investigate the potential for liquefaction of the sandy soil layer in wind power farms. In this study, the liquefaction potential of sand distributed in onshore wind power farms in Soc Trang province, Vietnam was evaluated using the undrained cyclic triaxial test. The sand specimens were remolded using dry pluviation and moist tamping methods to simulate the field density. The analysis of test results showed that the very fine sand with a loose state distributed at the depth of less than or equal to 11.5 m could be liquefied under the testing conditions. While the fine sand specimens with a dense to very dense state distributed deeper than 30 m were not liquefied under testing conditions. However, for these specimens, the pore water ratio could be increased by 11.3 to 18.6% and this increase can lead to a decrease in soil strength.