随着无支架缆索吊装斜拉扣挂法在钢管混凝土拱桥中的应用,为合理、简便地确定钢管混凝土拱桥扣索张拉力,提出了基于响应面法的钢管混凝土拱桥扣索张拉力的确定方法.该方法包括试验设计、有限元模型计算、响应面模型回归及扣索张拉力确定.以实桥工程为例,采用Box-BehnkenDesign进行试验设计,通过二次多项式回归的响应面模型将扣索张拉力与结构响应间的隐式关系显示化.以回归的响应面模型为目标函数,扣索张拉力取值为约束条件,采用非线性规划方法求解扣索张拉力.研究表明:该方法可以合理、简便地确定钢管混凝土拱桥扣索张拉力,对工程实践有较强的借鉴意义.
With the application of cable erection and strayed knotting method without support used in the concrete filled steel tubular(CFST) arch bridges, the approach which is used to conveniently determine the supporting cables' tensioning force based on response surface was proposed, which included the experi ment design, finite element analysis, response surface model and tensioning forces' determination. Taking the practical engineering for example, the method of Box-Behnken was used to design the sample; and the implicit relationship between tensioning force and structural response was altered to quadratic polynomial explicitly. According to the objective function required from the response surface model and the con straints, the nonlinear programming method was used to get the result of tensioning force. The results in- dicate that the method can be used to determine the reasonable tensioning force conveniently,so as to pro vide a meaning reference for engineering practice.