作　　者： ;

机构地区： 广东交通职业技术学院

出　　处： 《土木工程与管理学报》 2020年第1期112-119,125,共9页

摘　　要： 土性参数空间变异性是土性不确定性的一个主要来源,对岩土结构稳定性影响非常大,但目前多数研究采用间接近似的隐式模型模拟,采用直接明确的显式模型模拟的研究较少。本文将基于蒙特卡洛模拟的可靠度方法与随机场理论相结合,建立基于随机场理论的桩基可靠度分析方法,采用随机场法直接明确地模拟土性参数空间变异性,并基于钻孔桩实例分析土性参数空间变异性对钻孔桩可靠度设计的影响。结果表明,土性参数空间变异性对桩基设计结果影响很大,忽略空间变异性将导致设计结果更保守,土性参数空间变异性对小直径钻孔桩的设计结果影响更突出。另外,文章还采用等效方差折减法间接近似地模拟空间变异性,结果表明,采用方差折减函数简化形式的等效方差折减法模拟设计结果偏保守。 The inherent spatial variability has been considered as a major source of uncertainties in soil properties.It significantly affects the performance of geotechnical structures.However,most of the current studies use the implicit model of indirect approximation to simulate it,and there are few studies using a direct explicit method to model.This paper integrates a Monte Carlo simulation-based Reliability-Based Design(RBD)approach with the random field theory to establish a reliability analysis method for pile foundation based on random field theory and simulate the spatial variability by random field method directly and explicitly.Then,the effect of spatial variability of soil on the RBD of pile foundations is analyzed based on a drilled shaft example.The results show that the spatial variability of soil affects feasible designs of drilled shafts significantly.Ignoring spatial variability leads to conservative designs.The spatial variability has a greater impact on the design of small diameter drilled shafts.In addition,the paper also uses the equivalent variance reduction method to model,indirectly and approximately,the spatial variability of soil parameters.It is found that the indirect modeling using the equivalent variance reduction method with the simplified form of variance reduction function in RBD might lead to relatively conservative designs.

关 键 词： 随机场 空间变异性 桩基础 可靠度设计 等效方差折减法

领　　域： []