节点刚度对四边支承单层柱面网壳稳定性的影响  

Influence of joint stiffness on the stability of single-layer cylindrical reticulated shells supported along four edges

作　　者：康菊[1] 杨文伟[1] 

机构地区：[1]宁夏大学土木与水利工程学院,宁夏银川750021

出　　处：《空间结构》2012年第4期39-43,54,共6页Spatial Structures

基　　金：国家自然科学基金资助项目(50968014);宁夏区自然科学基金资助项目(NZ12164);宁夏大学自然科学基金资助项目(ZR1117);宁夏节水灌溉与水资源调控工程技术研究中心资助项目

摘　　要：利用ANSYS有限元软件建立了半刚性节点单元模型,对四边支承单层柱面网壳进行了几何非线性全过程分析,主要考察考虑初始几何缺陷和荷载不对称分布情况下,节点刚度变化对柱面网壳稳定性的影响规律.研究结果表明,四边支承单层柱面网壳当缺陷相同时,刚度减弱,极限荷载下降,且抗弯刚度的影响较强;缺陷增大,扭转刚度对四边支承柱面网壳的影响增强;同一刚度下,随着缺陷的扩大,极限荷载呈下降趋势,随着刚度的减小,缺陷对网壳极限荷载的影响程度减弱;荷载不对称分布导致四边支承柱面网壳结构极限荷载降低至对称荷载作用情况的80%左右,缺陷变化使得节点刚度对极限荷载的影响程度有所改变,但对承载力终值影响不大.On the basis of the finite element analysis software ANSYS,the semi-rigid node model is presented and then the examples of single-layer cylindrical reticulated shells supported along four edges are analyzed using a complete-process method with geometric nonlinearity.The effect laws of the joint stiffness on its stability is investigated and the initial imperfection and unsymmetrical distribution of loads are taken into consideration.The result show that with the same imperfection,the critical loads go down when the stiffness weakens,The effect of the bending stiffness is great.The rotation stiffness has a stronger effect on the single-layer cylindrical reticulated shells supported along four edges when the imperfection grows.With the same stiffness,the critical loads go down when the imperfection grows.The imperfection＇s effect on critical loads weakens when the stiffness decrease.The unsymmetrical distribution of loads results in the decrease of critical loads of cylindrical reticulated shells supported along four edges to a level of 80% of that in symmetrical distribution of loads.The variations of the imperfection bring changes in joint stiffness＇ effect on the critical loads and have little effect on the terminal bearing capability.

关 键 词：单层柱面网壳 节点刚度 初始缺陷 稳定性 

分 类 号：TU393.3[建筑科学—结构工程]