地铁车站抗拔桩侧摩阻力试验研究

Experimental Study on Shaft Resistance of Uplift Pile of Metro Station

采用自平衡法和滑动测微计法对地铁车站的嵌岩抗拔桩进行了侧摩阻力试验,采用自平衡法进行了嵌岩桩的抗拔试验,同时在桩身埋设滑动测微管,研究桩侧摩阻力的分布规律。研究表明,桩侧摩阻力随深度自下而上递减,且受桩身弹性模量的影响。试验测试得到的摩阻力分布曲线需进行断面修正和回归处理方能得到合理的试验结果。自平衡试验方法可与传统的抗拔试验做对比,验证桩基抗拔承载力,试验结果可为相关抗拔桩测试提供参考。

Based on self-balanced method and sliding micrometer method, the experiments to study the uplift ca- pacity of the piles socketed in rock is conducted in this paper, where the uplift test of the piles is carried out by self- balanced method and sliding micro tubes are embedded in the pile body to measure the distribution of shaft friction- al resistance. The results show that the shaft frictional resistance increases with the depth and is mainly affected by the elastic modulus of the piles. Reasonable prediction of the frictional resistance distribution can be obtained after modifications based on cross section correction and regression processing. The uplift bearing capacity of pile foun- dations captured by self-balanced method is verified by comparing with traditional uplift test. The methods em- ployed in this paper and their results can provide references for further tests of uplift piles.