自平衡测桩技术中“平衡点”位置确定  

Balance position determination in osterberg pile testing technique

作　　者：杨忠[1] 佴磊[1] 

机构地区：[1]吉林大学建设工程学院,长春130026

出　　处：《水文地质工程地质》2006年第3期117-120,共4页Hydrogeology & Engineering Geology

基　　金：吉林省交通厅科研项目(2003-1-13)

摘　　要：本文介绍了规范经验值法、相似模拟试验法及数值模拟分析法确定自平衡测试技术中平衡点的位置。实践表明规范经验值法确定的平衡点位置往往距离桩端过高;数值模拟分析法不能精确的选取计算参数致使结果存在一定的偏差;相似模拟试验法同时考虑了地层环境、成孔成桩工艺等因素的影响,所得结论较其他两种方法准确。文章以龙华松花江特大桥三根试桩为例,分别应用三种方法进行研究,结果表明应用相似模拟试验法确定平衡点的位置准确可靠,可直接应用于工程实践。The paper introduces three methods to determine the balance point position in Osterberg pile testing technique, the standard empirical value method, the simulation test method and the numerical value simulation analysis method. All of them hold the principle that the limit bearing capacity of the pile up the balance point equals to the part under the balance point. But it is found that the balance point position decided by the standard empirical value method is often too high to the bottom of the pile, while the numerical value simulation analysis method has certain deviation because of inaccurate selecting calculation parameters. The simulation test method bases on classical Mohr-Colum intensity theory and the friction simulation test between the pile and the ground, it considers simultaneously the influence from the factors such as strata environment, the pile-making technics and etc, the conclusion drawn from it is more accurate than the other two methods. The article separately uses three methods to test piles of the special large bridge of Songhuajiang River in Longhua and indicates that applying the simulation test method to the balance point position is accurate and reliable which can be applied to the engineering practice directly.

关 键 词：自平衡法 平衡点 模拟试验 有限元 

分 类 号：P624.8[天文地球—地质矿产勘探]