半刚性钢框架优化设计研究

推导了考虑连接柔性和几何非线性的局部坐标下的单元刚度矩阵,并对半刚性连接单元的固端力进行了修正;其次,采用增量加载法,给出了考虑连接柔性、框架的几何非线性和单元内力与连接之间耦合效应的半刚性钢框架结构分析计算机流程;按照GB50017-2003《钢结构设计规范》和实际施工的要求,建立了考虑构件和连接最小费用问题的半刚性钢框架优化数学模型;然后,在遗传算法和半刚性钢框架结构分析流程的基础上,给出了半刚性钢框架优化设计步骤;根据算例,对半刚性钢框架优化设计做了初步的探讨。

Optimum design of semi-rigid steel frame

Element stiffness matrix in local coordinate system is derived firstly,which takes the effects of the flexibility of the connections and the geometric nonlinearity of the members into account,and fixed-end forces with semi-rigid connections are modified.And then,a computer-based procedure with incremental loading method is presented for the analysis of semi-rigid steel frames,which accounts for the effects of the nonlinear behavior of the connections and P-delta as well as the coupling effect of element forces and connections.Next,an optimization model for design of semi-rigid steel frames involving the minimization of combined member and connection costs is proposed,according to the Chinese code for design of steel structures(GB50017-2003).After that,a genetic algorithm based procedure in optimum design of semi-rigid steel frames is presented.Finally,one example is provided to demonstrate the validity and effectiveness of the optimum design procedure of semi-rigid steel frames.Some conclusions can be draw from the results of the example.