基于自平衡试桩法的灌注桩承载力检测应用研究

探讨采用自平衡试桩法对承载大吨位、大直径、超长的灌注桩进行单桩竖向承载力检测的可行性。以南水北调中线工程磁县段二标滏阳河渡槽3号墩台8号灌注桩的单桩承载力检测为例,结合相关规范规程与自平衡测桩法检测原理,根据读数绘出向上向下的Q-s曲线及相应的s-lgt、s-logQ曲线,分别求得荷载箱上段桩及下段桩的极限承载力,将上段桩极限承载力经一定处理后与下段桩极限承载力相加即为桩极限承载力。结果表明：采用自平衡法测试技术不仅可短时间内测出桩身的桩基侧阻力,而且此装置较简单,不占用场地,可多根同时检测,试桩准备工作省时、省力、安全,试验费用省,特别是在狭窄场地试桩、基坑底试桩等方面优势突出,是传统试桩法难以实现的。

Application and Research of Pile Bearing Capacity based on Self-balancing Test Piles

Discussion on the feasibility of large tonnage,large diameter,long pile of vertical bearing capacity test based on self-balanced load test piles.Taking the Fuyang river aqueduct piers 3,No.8 of Cixian＇sⅡbid section of the South-to-North Water Transfer Project middle line as an example.According to the related codes and detection of self-balancing principle of testing pile,reading down the Q-s curve and the corresponding s-lgt,s-logQ curve,ultimating load cases obtained of upper and lower pile.The upper pile ultimate bearing capacity by a certain treatment and add the following paragraph is the ultimate bearing capacity of pile ultimate bearing capacity of pile.The results showed that the self-balancing test piles can not only measure the short pile of the pile side resistance,and this device is relatively simple,do not take up space,can simultaneously detect multiple,test pile preparation time,effort,security,test cost province,especially in the narrow field test piles,test pile foundation at the end so obvious advantages,which is difficult to achieve by the traditional test pile.