西南交通大学学报2017，Vol.52Issue(4)：705-714,10.DOI:10.3969/j.issn.0258-2724.2017.04.008
灌注桩套管振动贯入过程模型试验及数值模拟
Model Test and Numerical Simulation of Penetration Process of Sleeve for Cast-in-Place Piles Driven by Vibratory Hammers
摘要
Abstract
A model test was carried out to investigate the excess pore pressure, the radial extruding stresses, and the degree of soil plug of a vibratory driven sleeve for cast-in-place piles.A finite element model was also introduced by using the commercial code, ABAQUS.The results from the finite element analysis are in a strong agreement with the experimental observations.The results show that the excess pore pressure and radial extruding stresses increase to 1 kPa and 8 kPa, respectively;nevertheless, the extruding effect is mainly limited within a radial distance of about 6 times the sleeve diameter.The soil shear strength and granular cementation force decrease during vibratory sleeve driving, which is induced by cyclic shearing action in the shear interface.As a result, the inside sleeve of the soil plug is in an incompletely plugged mode.During vibratory sleeve driving, the soil plug in the sleeve end forms an annular soil arch, which gives rise to an obvious increase in internal friction resistance.The soil plug of this section withstands 80％ of the internal friction resistance.When the penetration depth is the same, the height of the soil plug in a saturated sand foundation is 1.2 times the height of the soil plug in a dry sand foundation.The vibration frequency, sleeve diameter, and saturation have significant effects on the soil plugging effect.关键词
灌注桩套管/振动贯入/模型试验/数值模拟/挤土/土塞Key words
sleeve for cast-in-place pile/vibratory driving/model test/numerical simulation/extruding effect/soil plugging effect分类
建筑与水利引用本文复制引用
肖勇杰,陈福全,董译之..灌注桩套管振动贯入过程模型试验及数值模拟[J].西南交通大学学报,2017,52(4):705-714,10.基金项目
国家自然科学基金资助项目(41272299) （41272299）
