深厚土层中长径比相近灌注桩承载性状  

Bearing behavior of cast-in-place piles with similar slenderness ratios in deep soil layer

作　　者：王学知[1,2] 赵春风[1] 赵洪平 

机构地区：[1]同济大学地下建筑与工程系,上海200092 [2]上海市建筑科学研究院(集团)有限公司上海建科建设监理咨询有限公司,上海200032 [3]常州市建设局市政管理处,江苏常州213003

出　　处：《辽宁工程技术大学学报（自然科学版）》2009年第6期957-960,共4页Journal of Liaoning Technical University (Natural Science)

基　　金：上海市重点学科建设基金资助项目(B308)

摘　　要：为了研究长径比相近灌注桩的承载性状,在常州高架道路工程城北干道一承台中设有两根桩径分别为1200mm、600mm长径比分别为42.5、45的钻孔灌注桩,分别对其进行静载荷试验和桩身应力测试结果分析。研究结果表明:桩端承载力低,两桩的载荷-沉降关系均表现为陡降型,且存在明显拐点;两桩桩身轴力分布曲线形态相似,小直径试桩的竖向载荷沿深度衰减规律相对于大直径试桩更接近于线性,载荷传递率更高;同一土层中直径较小试桩侧摩阻力略大于较大直径试桩,并且在其桩端附近出现明显大于同深度大直径试桩侧摩阻力的现象。该结论对深厚土层中灌注桩的设计、施工具有一定参考价值。To study the bearing behavior of cast-in-place piles with similar slenderness ratios in deep soil layer,a static load test and a pile stress measurement test are conducted on two piles,one with a diameter of 1200mm and an aspect ratio of 42.5,the other with a diameter of 600mm and an aspect ratio of 45.The piles are located in a pile cap at Chengbei Road,Changzhou.The study shows that the bearing capability of pile bottom is low,and the Q-S curves of both piles appear having a steep drop respectively with a significant inflection point.Although the curve shapes of both piles are similar,the load transfer ratio of later one is higher than that of former one.This is due to the fact that the load attenuation type of later one is much more close to linear than that of former one; the side friction of small pile is slightly larger than that of large pile.The study results provide a good example for designing and constructing cast-in-place pile.

关 键 词：钻孔灌注桩 载荷传递 承载性状 静载试验 

分 类 号：TU473.1[建筑科学—结构工程]