基于ANSYS的单层索网幕墙结构几何非线性有限元分析

Geometric nonlinear finite element analysis of single-layer cable curtain wall structure based on ANSYS

单层平面索网幕墙结构是一种通过对拉索施加预应力,为幕墙结构自身提供刚度,抵抗平面外荷载的结构体系。由于索网结构质量轻,阻尼小,对风荷载及地震荷载所引起的振动作用不容小觑,所以设计时除考虑平面内玻璃自重外,风荷载和地震荷载也应加以考虑。本文基于北京中关村生命科学园项目单层索网幕墙结构设计和施工方案设计,初步拟定设计方案。计算作用于幕墙结构上的荷载,通过ANSYS14.0有限元软件采用更加先进的LINK180单元模拟不锈钢拉索,建立单层索网幕墙结构理论分析模型,充分考虑结构的初应力和几何非线性,对拉索的受力状态及拉索边界连接点的反力进行研究。计算幕墙自重和风荷载标准值作用下索网的挠度,确定产生最大挠度的位置及最大挠度值,依据规范要求,对索网最大挠度值进行验算;在组合荷载作用下,对索网结构中拉索承受的拉力进行计算,分别确定橫索和竖索产生最大拉力的位置和大小,依据规范对拉力值进行验算;计算索网结构与边界连接各点的反力,介绍过载保护器的工作原理及其在单层索网幕墙结构中的应用。通过模型计算结果验证了设计的可行性,分析幕墙结构在设计和施工中要把握的要点及需要注意的问题,对其它类似项目的设计和实施具有借鉴意义。

The single-layer cable curtain wall structure is some kind of structural system that applies prestress to the cable to provide rigidity for the curtain wall structure and resists out-of-plane loads. Due to the light weight and small damping of the cable structure, the vibration effects caused by wind and seismic must not be underestimated. Therefore, in addition to considering the weight of the glass in the plane, the wind load and seismic load should also be taken into account when designing. Based on the structure design and construction scheme design of Beijing Life Park Project, this paper initially drafted a design scheme. Calculate the load acting on the curtain wall structure.The theoretical analysis model of the single-layer cable curtain wall structure are established in this paper, the more advanced LINK180 element of ANSYS14.0 is used to simulate stainless steel cable, the initial stress and geometric nonlinearity of the structure are taken into account. The stress state of the cable and the reaction force at the connection point of the cable are studied.This paper calculated the deflection of the cable under the standard value of the curtain wall self-weight and wind load. Located the point where the maximum deflection occurs and calculated its value, check the maximumdeflection value of the cable according to the code. This paper calculated the pull force of the cable under the combined load, and the position and size of the maximum pulling force generated by the lateral cable and the vertical cable are calculated respectively. The pull value is checked according to the code. The reaction force of each point of boundary is calculated. The principle of the overload protection device and its application in singlelayer cable curtain wall structure is introduced. This paper verified the feasibility of the design by the results of the model calculation, and analyzed the points in the design and construction of the curtain wall structure. The design and implementation of other similar projects would be inspired by this paper.