钻孔灌注桩成孔卸荷时效性理论研究  

THE RESEARCH ABOUT MECHANISM ON UNLOADING TIME EFFECT CAST-IN-PLACE BORED PILES

作　　者：鲁嘉 赵春风[1] 刘福天[1] 李尚飞[1] 

机构地区：[1]同济大学岩土及地下工程教育部重点实验室地下建筑与工程系,上海200092

出　　处：《低温建筑技术》2009年第2期84-86,102,共4页Low Temperature Architecture Technology

基　　金：上海市重点学科建设项目资助(No.B308);上海城建(集团)公司计划项目

摘　　要：针对钻孔灌注桩钻孔的卸荷效应及孔周土体的粘弹性,分析了孔壁受力变化机理。另外,考虑钻孔卸荷时孔周土体松弛及蠕变特性,以标准线性固体模型中的推广Kelvin体为桩周土的流变模型,推导钻孔卸荷后,孔壁水平应力和位移随时间的变化的公式,对深入研究钻孔的流变特性及其卸荷效应影响具有重要意义。The paper analyzes the mechanism of the variation of load enforced on cavities based on the unloading effect of cast - in - place bored piles and property of viscoelastic of soil around piles. Otherwise, the formula of horizontal geostress and displacement of cavities with time is detruded based on H - K rheologi- cal model of soil around pile under unloading effect, considering the property of laxation and creep of soil, which has significant meaning to the further study of creep effect of cavities and influence of unloading effect to the bearing mechanism of cast - in - place bored piles.

关 键 词：卸荷 桩周土 流变模型 松弛 拉普拉斯变换 

分 类 号：TU473.1[建筑科学—结构工程]