基于边界面模型的砂土中板锚循环承载力数值分析  

Numerical analysis of cyclic bearing capacity of plate anchors in sand based on boundary surface model

作　　者：王强 刘海笑[1] 李洲[1] WANG Qiang;LIU Haixiao;LI Zhou(School of Civil Engineering,Tianjin University,Tianjin 300072,China)

机构地区：[1]天津大学建筑工程学院,天津300072

出　　处：《海洋工程》2021年第3期83-94,共12页The Ocean Engineering

基　　金：国家自然科学基金重点项目(51539008)。

摘　　要：利用带误差控制的显式积分算法,将一种适用于饱和砂土排水循环动力分析的边界面塑性模型编写成可供有限元软件调用的用户自定义材料子程序。建立土体单元有限元数值模型对Toyoura砂的静、动排水三轴试验进行模拟,验证了模型具备合理描述砂土在不同荷载条件下力学响应的能力。建立饱和砂土中板锚循环承载分析的数值模型,针对板锚在砂土中的单调抗拔特性和循环承载特性进行数值分析,得到了与模型试验一致的荷载—位移响应规律。考察循环荷载要素对板锚循环承载特性的影响,结果发现,随着循环荷载的施加,板锚永久位移逐渐累积,循环荷载会导致板锚持续移动,循环幅值越大,初始位移和位移变化率越大;循环均值越大,初始位移越大,但位移变化率越小。Using an explicit integral algorithm with error control,a bounding⁃surface plasticity model for cyclic loading analysis of sand is programmed into a user⁃defined material subroutine which can be called by a finite element software.A finite element model of soil element is developed to simulate triaxial tests of Toyoura sand under monotonic and cyclic loading.The simulation results agree well with the model tests,proving that the built model can reasonably describe the mechanical response of sand under different loading conditions.A finite element model of a plate anchor is established to simulate the anchor response under monotonic loading and cyclic loading.The obtained load⁃displacement response law is in good agreement with of the model test results.By investigating the influence of cyclic loading factors on the cyclic bearing characteristics of plate anchor,it is found that with the application of the cyclic load,the permanent displacement of the plate anchor gradually accumulates,and the cyclic load will cause the plate anchor to move continuously.Furthermore the larger the cyclic amplitude is,the larger the initial displacement and displacement change rate are.Larger cyclic mean produces larger initial displacement,but smaller displacement accumulating rate.

关 键 词：边界面塑性模型 显式积分算法 数值分析模型 循环承载力 板锚 

分 类 号：P754[天文地球—海洋科学] TU435[建筑科学—岩土工程]