基于累积耗损能量的饱和粉土液化特性试验研究

Experimental Study of Liquefaction Characteristics of Saturated Silt Based on the Cumulative Dissipated Energy

摘要:

饱和粉土场地在强地震作用下易发生液化现象。开展饱和粉土的循环三轴试验,以循环加载的累积耗损能量为指标,探讨黏粒含量、密实度、有效围压和循环应力比等因素对粉土液化特性的影响,试验结果表明:粉土液化所需的耗损能量随黏粒含量的增加呈先减小后增大的趋势,当黏粒含量约为8%时粉土的液化耗损能量最低;液化耗损能量随粉土密实程度的增大而逐渐增加,并随初始有效围压的增长而增加,但粉土的液化耗损能量与循环应力比之间的关系不明显。

Abstract:

Liquefaction of saturated silty soil can easily occur during strong earthquakes.To investigate the liquefaction of a saturated silt mixture, a series of cyclic triaxial tests is conducted.Some factors such as clay particle content, relative density, effective confining stress, and cyclic stress ratio are examined by analyzing the cumulative dissipated energy for triggering liquefaction.The results show that for low (high)values of clay particle content, an increase in clay particle content with the same relative density leads to a decrease (increase) in cumulative dissipated energy.The effective confining pressure and relative density have strong effects on the cumulative dissipated energy.However, the cumulative dissipated energy is independent of the cyclic stress ratio for the specimens with constant relative density and confining pressure.