摘要
为研究桩基承载力高应变法和静载法的检测差异,收集工程现场76根PHC管桩的高应变法和静载法检测结果进行对比。以静载法的承载力检测结果为基准,对比分析引起高应变法承载力检测误差的主要原因,探讨以桩基高应变法检测结果推算桩基静载法检测结果的可行性。结果表明:约84.2%检测桩的高应变法承载力误差控制在±10%以内,且高应变法承载力结果大于或小于静载法承载力结果的概率相当,无明显偏向性;对于缓变型短桩,高应变法桩顶沉降主要分布在10~20mm范围内,对应的静载法桩顶沉降分布范围为10~40mm;采用线性函数模型拟合高应变法和静载法桩顶陡降型沉降曲线是合适的,相关系数达0.86以上。根据荷载-沉降曲线特点、桩长径比、桩端持力层条件进行桩基分类后,再采用高应变法结果预测静载法结果,预测准确度更好。
In order to study the detection difference between the high strain method and the static load method for the bearing capacity of the pile foundation, detection results of 76 PHC pipe piles at the project site with high strain method and static load method were collected for comparison. Based on the bearing capacity detection results of the static load method, the main causes of the bearing capacity detection errors by using the high strain method were compared and analyzed, and the feasibility of using the detection results of high strain method to estimate to the detection results of static load method for the pile foundation was discussed. The results show that high strain method bearing capacity detection error of PHC pipe piles about 84.2% is controlled within ±10%, the probability of the dynamic strain result being greater than or less than the static load result is equivalent, and there is no obvious bias. For short piles with slowly changing load-settlement curves, the pile top settlement with high strain method mainly changes within the range of 10 to 20 mm, and the corresponding the pile top settlement with static load method vary from 10 to 40 mm. The linear function model is suitable to fit the steep-declining settlement curve of pile top based on high strain method and static load method, and the correlation coefficient is above 0.86. before using the high strain results to estimate the static load results, pile foundations must be firstly classified according to the characteristics of the load-settlement curve, the length-to-diameter ratio of piles and the pile end bearing layer, which will result in higher prediction accuracy.
作者
刘春林
唐孟雄
胡贺松
陈航
刘陈希
侯振坤
LIU Chunlin;TANG Mengxiong;HU Hesong;CHEN Hang;LIU Chenxi;HOU Zhenkun(Guangzhou Institute of Building Science Co.,Ltd.,Guangzhou 510440,China;Guangzhou Testing Centre of Construction Quality and Safety Co.,Ltd.,Guangzhou 510440,China;School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,China)
出处
《建筑结构》
CSCD
北大核心
2022年第14期136-140,共5页
Building Structure
基金
国家自然科学基金项目(51908225)
广州市建筑集团科技计划项目(2020⁃KJ002、2020⁃KJ007、2021⁃KJ022)
广州市建筑科学研究院科技进步项目(2021Y⁃KJ04、2020Y⁃KJ05)。
关键词
PHC管桩
高应变法
静载法
承载力
桩顶沉降
PHC pipe pile
high strain method
static load method
bearing capacity
pile top settlement
