路堤下粉喷桩复合地基现场试验研究

针对粉喷桩复合地基性状进行了现场试验研究,包括地基的沉降、深层水平位移、孔隙水压力、桩-土应力比、桩身应变等。试验结果表明:(1)粉喷桩复合地基工后沉降能满足设计要求:(2)采用桩长渐变的方法可完成从桥台到一般路基的沉降平滑过渡;(3)地基深层水平位移小,有利于地基的稳定和减小地基对桥台基础的影响;(4)超静孔压消散慢,但孔压值不大,对沉降稳定影响不大;(5)桩-土应力比较大;(6)桩身应变与桩顶土压力具有较好的线性关系。

FIELD TESTING STUDY ON COMPOSITE FOUNDATION OF DJM PILE UNDER ROAD EMBANKMENT

The behaviors of composite foundation of DJM pile were studied through field test, including settlement, deep horizontal displacement, excess pore water pressure, stress ratio of pile to soil, and pile strain. The test results show that(1) the post-construction settlement can meet design requirements, (2) the settlement transits smoothly from the bridge pier to road embankments when the pile length is gradually changed, (3) the deep horizontal displacement of foundation is small enough to keep foundation stable and reduce the influence of foundation on bridge pier, (4) the excess pore water pressure dissipates slowly, but it's value is not large enough to have evident influence on stability of the settlement, (5)the stress ration of pile to soil is large in this case, and (6) there is linear relationship between soil pressure and DJM pile strain.