中风化花岗岩中嵌岩桩承载性能原位试验与极限承载力预测
In-Situ Test and Numerical Simulation on Bearing Characters of Rock-socketed Pile for Medium Weathered Granite
刘超 1白晓宇 1银吉超 1卫永辉 2谭永明 3孟德朝4
作者信息
- 1. 青岛理工大学 土木工程学院,山东 青岛 266520
- 2. 中建四局西北建设有限公司,陕西 西安 710117
- 3. 中铁二十二局集团有限公司,北京 100043
- 4. 中国建筑第五工程局有限公司,湖南 长沙 410004
- 折叠
摘要
为深入探究中风化花岗岩中嵌岩桩的竖向抗压承载特性,对 12 根嵌岩桩进行了单桩竖向抗压静载原位试验与ABAQUS有限元数值模拟,通过多种方法对嵌岩单桩极限承载力进行评价,明确中风化花岗岩中嵌岩桩竖向抗压承载性状.研究表明:12 根中风化花岗岩中嵌岩桩并非表现出完全端承桩,而是呈摩擦型桩或摩擦端承桩的性状;中风化花岗岩地基中的嵌岩桩竖向抗压极限承载力较高,桩顶沉降小,满足工程对基础的承载要求;有限元模拟荷载-沉降曲线与实测荷载-沉降曲线走势吻合度较高,桩顶沉降误差较小;本试验条件下,桩端阻力占桩顶荷载的 56.9%,桩侧摩阻力占比为43.1%,桩侧摩阻力在荷载传递过程中发挥较充分;有限元模拟得到的单桩极限承载力与指数函数模型的预测结果较为吻合,可用于嵌岩桩单桩竖向抗压极限承载力的预测,以及嵌岩桩承载性状和荷载传递规律的分析.
Abstract
To investigate the vertical compressive load bearing characteristics of rock-socketed piles in medium-weathered granite,this paper carried out in-situ tests and ABAQUS finite element numerical simulations on 12 rock-socketed piles to evaluate the ultimate bearing capacity of rock-socketed piles by various methods and to clarify the vertical compressive load bearing characteristics of rock-socketed piles in medium-weathered granite.The study shows that the 12 rock-socketed piles in medium-weathered granite do not exhibit fully end-bearing piles,but are friction piles or friction end-bearing piles;the ver-tical compressive ultimate bearing capacity of rock-socketed piles in medium-weathered granite founda-tion is high,and the settlement at the top of the piles is small,which meets the bearing requirements of the foundation.The finite element simulation load-settlement curve matches well with the measured load-settlement curve,and the pile top settlement error is small;under this test condition,the pile end resistance accounts for 56.9% of the pile top load,and the pile side friction resistance accounts for 43.1%,and the pile side friction resistance plays a sufficient role in the load transfer process.The ulti-mate pile load capacity obtained from finite element simulation is in good agreement with the prediction result of exponential function model,which can be used for the prediction of vertical compressive ulti-mate load capacity of rock-socketed pile and the analysis of bearing characteristics and load transfer law of rock-socketed pile.
关键词
嵌岩桩/中风化花岗岩/承载性能/原位试验/单桩极限承载力预测/数值模拟Key words
rock-socketed pile/medium weathered granite/bearing characters/in-situ test/predic-tion of ultimate bearing capacity of single pile/numerical simulation引用本文复制引用
基金项目
山东省自然科学基金重点项目(ZR2020KE009)
国家自然科学基金(51778312)
出版年
2024
NETL
NSTL
万方数据