非均质地基土条件下的钻孔灌注长桩竖向承载性状分析研究  

Study on bearing behaviors of long bored piles in the heterogeneous strata

作　　者：周宏磊[1,2] 陶连金[1] 王法[2] 

机构地区：[1]北京工业大学,北京100044 [2]北京市勘察设计研究院有限公司,北京100038

出　　处：《工程勘察》2009年第12期26-30,39,共6页Geotechnical Investigation & Surveying

基　　金：北京市自然科学基金(8062007);科技部"十一五"科技支撑项目(2006BAJ06B02)

摘　　要：本文以北京地区典型第四纪冲洪积交互地层条件下的钻孔灌注桩为研究对象,基于单桩竖向抗压静载试验结果,对长桩荷载传递特征、荷载-变形性状进行了分析。在研究对比本地区多个场地现场桩基试验结果和统计与分析的基础上,提出了基桩荷载-变形数值分析中的地基土模量修正方法。按本文提出的方法,数值计算分析得到的单桩荷载-沉降曲线、桩身内力和变形结果,与现场实测结果基本相符,从而为在非均质互层地基条件下估算基桩承载力、合理确定有效桩长及深入分析桩的侧阻力、端阻力的发挥提供可靠的研究分析方法。Taking the projects with long bored piles in the typical alluvial-proluvial inter-bedded strata of the Quaternary Period in Beijing area as the research objects, the load transfer mechanism and the load-settlement behaviors of long bored piles are studied based on the vertical loading test results. Through comparing and statistically analyzing the vertical loading test results from several projects with long bored piles in Beijing area, an empirical formula is put forward to calculate the soil modulus with the numerical simulation. The numerical simulation results show that the load-settlement curves, the distribution of the shaft axial force and the deformation simulated by using this method basically accord with the field testing results. It could provide a reliable analytical method for estimating the ultimate load-bearing capacity, determining the effective length and analyzing the lateral friction and end bearing behavior of long single pile in the heterogeneous strata.

关 键 词：非均质地层 长桩 承载性状 变形特性 数值分析 

分 类 号：TU473.1[建筑科学—结构工程]