张弦梁结构张拉过程中的结构性能试验研究

Experimental study on structural performance during prestressing of beam string structure

基于正交试验设计思想,设计了11组考虑梁弦刚度比、矢跨比、撑杆数量、临时支架和施工顺序等参数影响的张弦梁模型并进行张拉试验。通过试验研究,探讨了张弦梁结构张拉过程中的整体变形性能、构件内力和几何位形的发展趋势,分析了参数对结构性能的影响。研究结果表明:当张拉引起的变形较大时,张拉力与结构变形并非简单的线性关系;临界张拉力标志结构获得整体刚度,其值约为结构自重的0.125/κ倍(κ为矢跨比);张弦梁结构设计中应考虑张拉阶段结构的最不利受力、不同施工工艺对结构受力和位形的影响。

Experimental study has been carried out to investigate comprehensively the behavior of BSS during prestressing. Based on the theory of orthogonal test, 11 BSS specimens were designed and tested. The deflection, inner force and configuration of BSS during prestressing were investigated. Furthermore, the sensitivity of the structural performance during prestressing to various parameters has been obtained from the analysis of the orthogonal test. Experimental results show that： when the displacement caused by the pre-tension force is large enough, the relationship between the pre-tension force and the structural displacement becomes non-linear; the critical pre-tension force is approximate 0.125/k of the structural weight, at which BSS gets its overall rigidity; the undesirable force in the member during prestressing and the influence of different construction methods on structural behaviour and geometric configuration, should be considered in the design of BSS.