透水与隔水夹层对粉质土液化影响试验研究

EXPERIMENTAL STUDY ON EFFECTS OF THE PERMEABLE AND IMPERMEABLE INTERLAYERS ON LIQUEFACATION OF THE SEABED OF ESTUARY OF THE YELLOW RIVER

黄河三角洲沉积物以粉质土为主,循环荷载作用下隔水夹层与透水夹层的存在对粉质土孔压累积、消散及液化的影响如何,目前尚不清楚。本文针对4种隔水夹层与透水夹层的组合情况,利用现场原位振动和室内土样振动试验,研究隔水夹层与透水夹层的存在对循环荷载作用下黄河口粉质海床土液化过程影响,发现循环荷载导致黄河三角洲粉质土孔隙水压力、粒度成分、密度、含水量及孔隙比等物性指标发生的变化,因夹层的不同有明显的差异,并且其液化性能因夹层结构的不同而不同,有透水夹层时,相对提高了粉土的抗液化性能,隔水夹层则相反。

The primary sediment in the Yellow River delta is silt. It is not clear how the permeable and impermeable interlayers impact on the accumulation of the pore water pressure,dissipation and liquefaction of sediments under the cyclic loading. This paper presents results of in - situ vibration test and lab tests for four kinds of interlayers. The resuhs show that physical and mechanical properties of the silt, such as the pore water pressure, grain size composition, density, water contents etc. vary with the type of interlayero A permeable layer improves its resistance against liquefaction, while an impermeable interlayer is opposite.