单向或双向单层平面索网幕墙结构体系中竖索受力和变形较复杂,对其解析分析有重要意义,但缺乏深入研究。该文将其等效为双向均布荷载作用下的预应力竖索,以形成一种解析求解方法。针对其施工和结构特征,首次提出3阶段分析方案,并对主要的后2个阶段,分别建立考虑轴向荷载影响的平衡方程和变形协调方程。通过求解平衡方程得到竖索竖向位移方程和横向挠曲方程,并首次得到挠度极值位置与轴向荷载影响的关系公式。该文还给出了第3阶段的两种多项式近似挠曲方程,并在求解过程中,对3种不同挠曲线求解分别进行简化处理,给出迭代策略。算例表明该文解析方法得到的结果均与有限元法吻合良好,说明该文分析方案和结果正确,近似方程也能保证很好的精度。
Internal force and deformation of vertical cables in unidirectional or bidirectional single-layer plane cable net curtain wall structural system are always rather complex. Its analytic analysis is therefore an important theoretical basis for the analysis of the whole structure, but, corresponding research on this subject is very limited. This paper treats it as an equivalent pretensioned vertical cable under bidirectional uniform load, and tries to find an analytic method. According to the load and deformation characteristics, an analysis scheme are firstly brought forward, which includes three phases. And, for the latter two phases which are more important, the paper establishes equilibrium equations and deformation compatibility equations considering the axial load effects. By solving the equilibrium equations, the vertical displacement equation and horizontal deflection equation of vertical cables are obtained, and the formula that reflects the variation of extreme deflection position and axial load effects is found. This paper also gives the deflection equation at the third stage, which is expressed as two polynomial approximations respectively, and moreover, the simplified form and iteration solution. Calculation examples show that the analytic method has good agreement with finite element method, indicating that the analysis scheme and results are correct and the approximated deflection equations have good accuracy.