饱和砂土地基液化特性振动台试验研究

饱和砂土地基试验是研究碎石桩复合地基抗液化性能振动台试验的先导和必要组成部分。本文采用自行研制的简易单向专用振动台和大型叠层剪切变形模型箱完成了两个饱和砂土地基模型的三次振动台试验,验证了模型箱的性能和模型地基内部的均匀性。通过量测振动过程中砂土的超静孔隙水压力,得到了饱和砂土地基液化规律以及振动加密对其抗液化能力的影响。同时,探索了饱和砂土地基液化大型振动台模型试验技术,如饱和砂土模型地基设计与制备、传感器布置、试验加载方案确定等,为今后开展此类试验提供一般的研究思路,并且为后续碎石桩复合地基振动台试验提供了必要的技术经验。

Shaking table tests on liquefaction properties of saturated sand ground

Saturated sand ground tests are the leading and essential constituent of shaking table tests to study the characteristics of stone columns composite foundation. Shaking table tests on two saturated sand ground models were carried out three times by using the simple unidirectional exclusive shaking table and the large-scale laminar shear box developed independently by the authors. The validity of the model box and uniformity of the saturated sand model ground were shown by the tests. The liquefaction rules of saturated sand ground as well as the influence of its anti-liquefied ability after dynamic densification were obtained. At the same time, the large-scale shaking table test techniques of saturated sand ground were discussed, such as the design and preparation of saturated sand model ground, the arrangement of sensors and the test load program, which could be used as common reference to the same kind tests as well as necessary technical experience for subsequent shaking table tests on stone columns composite foundation in future.