弹性地基上柱下条形基础计算的有限元法  

Strip Foundation Calculation Under Columns on Elastic Ground Based on Finite Element Method

作　　者：杨建晖 戴自航[1] YANG Jianhui;DAI Zihang(College of Civil Engineering,Fuzhou University,Fuzhou,Fujian 350108,China)

机构地区：[1]福州大学土木工程学院,福建福州350108

出　　处：《水利与建筑工程学报》2020年第6期95-100,共6页Journal of Water Resources and Architectural Engineering

摘　　要：以弹性地基上某典型T形截面基础梁为例,探讨了采用ABAQUS程序进行该问题计算的有限元方法(FEM)。考虑到有限元法单元类型和网格密度对计算结果的影响,对比了采用不同单元类型、不同网格密度的计算结果,给出了在采用一阶单元类型进行基础梁内力计算时应采用8节点砖形非协调单元C3D8I的建议。由于有限元法摒弃了现行文克尔地基梁法和链杆法的简化假设,因而其计算结果是最为准确的。对于现行柱下条形基础的设计计算方法,对比分析表明,应尽量避免采用倒梁法,优先采用链杆法,其次是文克尔地基梁法。通过有限元法不仅方便高效地获得了基础梁的内力和沉降等,还首次揭示了基底反力的三维分布特征,有助于人们深入认识基础与地基的相互作用。因此,有条件时,建议的有限元法应作为设计人员进行柱下条形基础计算的首选方法。This paper take a typical T-shaped cross-section foundation beam on elastic ground as an example,finite element method(FEM)software ABAQUS was adopted to carry out the computation of the problem.Considering the effects of the element type and mesh density of the finite element method on the computation results,the computation results by different element types and different mesh densities were compared,and the 8-node brick element with the incompatible features C3D8I should be employed when using first-order elements to compute the internal forces of a foundation beam.Since the finite element method abandons the simplified assumptions of the prevailing Winkler foundation beam method and the connection-link method,its calculation results are very accurate.For the current design calculation methods of strip foundations under columns,the comparison analysis shows that the inverted beam method should be avoided as much as possible,and the connection-link method is preferred,followed by the Winker foundation beam method.The finite element method not only obtained the internal forces and settlement of the foundation beam conveniently and efficiently,but also revealed the three-dimensional distribution characteristics of the foundation base resistance for the first time,which is helpful to deeply understand the interaction between the foundation and the ground.Therefore,when conditions are permitted,the proposed finite element method should be the applied to conduct the calculation of strip foundations under columns.

关 键 词：弹性地基 柱下条形基础 相互作用 有限元法 内力 

分 类 号：TU452[建筑科学—岩土工程]