既有预应力空间索杆系结构的安全性评价方法

Safety evaluation method of existing prestressed cable truss structure

为解决考虑拉索腐蚀程度的既有预应力空间索杆系结构安全评价技术难题,研究建立了基于结构自身特性和拉索腐蚀程度的安全性客观评价方法。首先,建立了空间索杆系在瞬间断索下的动力响应分析方法,并通过三索结构算例验证了该方法的合理性和可行性;其次,根据判断矩阵构建理论和断索分析结果,建立了考虑拉索腐蚀程度的索杆系中各拉索权重系数确定方法;在此基础上,建立了拉索腐蚀程度的隶属函数,构建拉索索系的安全评语集,根据权重系数和拉索腐蚀程度检测结果,建立了既有预应力空间索系安全性的模糊综合评价体系。依托于某基于空间索杆系结构,对所构建的权重确定方法、隶属度函数和模糊综合评价模型进行了初步的应用和合理性验证。

In order to solve the safety evaluation problem of existing prestressed cable truss structures considering the corrosion degree of cables,an objective evaluation system is established based on the characteristics of the structure and the corrosion degree of the cables.Firstly,the dynamic response analysis method of cable-strut system under the instantaneous break is established,and the rationality and feasibility of proposed method are verified by three cable structures.According to the construction theory of judgment matrix and the result of the cable breaking analysis,the method for determining the weight coefficient of each cable in the cable-strut system is established considering the corrosion degree of the cable.On this basis,the membership function of the corrosion degree of the cable is established,and the safety evaluation set of the cable system is built.At last,based on the weight coefficient and the corrosion degree of the cable,the fuzzy comprehensive evaluation system is established for the safety of existing prestressed spatial cable system.Furthermore,the weight coefficient determination method,the membership function and the fuzzy comprehensive evaluation model are applied and verified by a practical spatial cable-strut structure.