群桩基础抗力系数和安全系数的可靠度设计  

Reliability design of resistance factor and safety factor for pile groups foundation

作　　者：边晓亚[1] 郑俊杰[1] 徐志军[2] 

机构地区：[1]华中科技大学土木工程与力学学院,湖北武汉430074 [2]河南工业大学土木建筑学院,河南郑州450052

出　　处：《华中科技大学学报（自然科学版）》2014年第3期87-91,共5页Journal of Huazhong University of Science and Technology(Natural Science Edition)

基　　金：国家自然科学基金资助项目(51278216);河南工业大学高层次人才基金资助项目(2013BS010)

摘　　要：针对由于群桩效应和系统效应的存在,群桩基础的可靠性分析与设计较为复杂这一问题,基于单桩可靠度分析与设计原理,考虑群桩效应和系统效应的影响,对抗力系数和安全系数进行修正,并结合桩基设计方法进行分析.研究结果表明:桩基设计方法、群桩效应和系统效应对抗力系数和安全系数影响很大.在满足目标可靠度水平条件下,当群桩效应系数和系统效应系数大于1时,可以提高抗力系数设计值,降低设计安全系数.忽视群桩效应和系统效应往往会导致设计方案过于保守,造成较大的浪费.Reliability design and analysis of pile groups foundation are more complex than those of single piles due to the pile group efficiency and system effect.Based on the principle of design and analysis of single piles,the pile group efficiency and system effect were carefully taken into account to calibrate resistance factor and safety factor for reliability-based design.In addition,the pile foundation design approach was treated as a key factor when conducting calibration of resistance factor and safety factor.The results through the case study indicate that pile foundation design approach,pile group efficiency,and system effect are three vital factors for the determination of resistance factor and safety factor.When pile group efficiency factor and system effect factor are greater than 1,a larger resistance factor and a smaller safety factor than those for single piles design can satisfy the requirements of reliability-based design of pile foundation under a given target reliability index.A conservative design scheme may be obtained due to ignoring pile group efficiency and system effect,which will cause tremendous economic consumption.

关 键 词：可靠度设计 群桩效应 系统效应 抗力系数 安全系数 

分 类 号：TU473[建筑科学—结构工程]