单桩静载试验的桩顶沉降稳定收敛特征研究  

The Stabilized Convergent Characteristics of Pile Top Settlement in Single Pile Static Loading Test

作　　者：谢鹏 董天文[1] 郑颖人 何嘉峰 张成 Xie Peng;Dong Tianwen;Zheng Yingren;He Jiafeng;Zhang Cheng(Civil Engineering College,Liaoning Technical University,Fuxin,Liaoning 123000,P.R.China;Department of Construction Engineering,Army Logistics University,Chongqing 401311,P.R.China;Zhejiang Hongyu Survey and Design Co.Ltd.,Zhoushan,Zhejiang 31600,P.R.China)

机构地区：[1]辽宁工程技术大学土木工程学院,辽宁阜新123000 [2]陆军勤务学院建筑工程系,重庆400041 [3]浙江宏宇勘察设计有限公司,浙江舟山316100

出　　处：《地下空间与工程学报》2022年第4期1276-1283,共8页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金项目(51178457);辽宁省自然科学基金项目(20180551140);舟山科技局项目(2020C11038)。

摘　　要：采用单桩静载试验,系统地对36根工程桩的324个荷载级进行沉降稳定分析和荷载稳定时间分析,并通过中等直径灌注桩和超长大直径嵌岩桩两种桩型的15根单桩进行了对比分析。研究表明:不论是嵌岩桩还是非嵌岩桩,各级荷载总体都在1小时内稳定且占比高达96.3%;桩顶的沉降速率、加速度均表现出随时间衰减的特征,证明了桩顶位移具有基于时间、位移的收敛的性特征,且试验耗时降低40%以上。采用P-s曲线法、LogP-s曲线法、E-Δs/ΔQ法判定了单桩的极限荷载,验证了桩顶沉降值在合理的范围之内,同时也表明对桩顶沉降收敛特征的研究可以有效的缩短桩基础检测的时间并提高检测效率。The settlement stability analysis and load stability time analysis were carried out systematically for 36 engineering piles with 324 load levels using single pile static load test, a comparative analysis of 15 engineering piles of medium-diameter cast-in-place piles and super-long large-diameter rock-stocked piles was carried out. The study shows that: whether rock-socketed piles or non-rock-socketed piles, all levels are generally stable within 1 hour and the proportion is as high as 96.3%;the settlement rate and acceleration of pile top show the characteristics of decay with time, which proves that the pile top displacement has the characteristics of displacement convergence, the static load test time might reasonably reduce 40% or more. The P-s curve method, LogP-s curve method and E-Δs/ΔQ method were used to determine the ultimate load of the single pile, which verified that the settlement value of the pile top was within a reasonable range, and also showed that the study of the convergence characteristics of the pile top settlement could effectively shorten the time and improve the efficiency of the pile foundation inspection.

关 键 词：单桩静载试验 荷载稳定时间 试验耗时 极限荷载 

分 类 号：TU44[建筑科学—岩土工程]