螺杆桩复合地基承载力计算及可靠性分析  

Calculation of Bearing Capacity and Reliability Analysis of Screw Pile Composite Foundation

作　　者：李强 LI Qiang(Lanzhou Railway Design Institute Co.,Ltd.,Lanzhou 730030,China)

机构地区：[1]兰州铁道设计院有限公司,甘肃兰州730030

出　　处：《甘肃科学学报》2023年第2期148-152,共5页Journal of Gansu Sciences

摘　　要：螺杆桩复合地基作为一种新型复合地基,具有承载力高、施工便捷等优势,被广泛应用在地基处理中,但对其可靠度的认识不足,需要进一步展开研究。基于Mohr-Coulomb强度理论,推导螺杆桩复合地基承载力公式,并建立对应的功能函数。依托某实际工程中的参数统计特征,利用JC法对螺杆桩复合地基可靠度的敏感性进行研究并分析其可靠性。研究结果表明:工程参数对螺杆桩复合地基承载力可靠度的影响存在明显的差异,其敏感性由强到弱依次为侧阻力>端阻力>内摩擦角>螺牙宽度>螺牙高度>螺牙净距>面积置换率;研究区螺杆桩复合地基失效概率最大约为5.04%,最小约为1.36%,均值约为3.11%。The screw pile composite foundation,as a new type of composite foundation,has such advantages as high bearing capacity and convenient construction,and is widely used in foundation treatment,however the understanding of its reliability is obviously insufficient,and a further relevant study is necessary.Based on the Mohr-Coulomb strength theory,the bearing capacity formula of screw pile composite foundation is derived and the corresponding functional function is established.Taking reliance on the statistical characteristics of parameters in an actual project,the sensitivity of the reliability of screw pile composite foundation is analyzed by JC method and its reliability is given.The study results show that there are significant differences in the influence of engineering parameters on the bearing capacity reliability of screw pile composite foundation,and their sensitivity from strong to weak in proper order are as followed pile lateral resistance,pile end resistance,internal friction angle,screw tooth width,screw tooth height,net distance of screw tooth,and area replacement rate.The maximum probability of failure of screw pile composite foundation in the study area is about 5.04%,the minimum is about 1.36%,and the mean is about 3.11%.

关 键 词：螺杆桩复合地基 功能函数 可靠性 JC法 敏感性 

分 类 号：TU473.1[建筑科学—结构工程]