拱桥拱轴线的优化与选形

根据拱轴线优化的基本原理,以一条初始的拱轴线形及某种特定的荷载工况为基础,建立有限元模型,分析拱轴线各节点、单元间力学关系,通过有限元程序的迭代计算,求得在特定荷载下拱圈上的各个离散点接近于压力线的坐标;再利用曲线拟合的方法得到可应用于实际工程的各次抛物线形,并通过比较确定出结构的最合理拱轴线。最后,给出了两个详细的工程算例,算例结果表明文中所提出算法较好的减少了拱轴线与压力线的偏差,改善了拱圈的受力状态。

Optimization and Selection of Arch Bridge Axis

The mechanics relationship of the nodes and elements on the arch bridge axis are analyzed by estimating a finite element(model) which is based on a primal arch bridge axis and a given load condition.Then in the light of the rationale of the optimization of arch bridge axis,particular attention is paid to the application of the iterative calculations of finite element method program to gain the(coordinates) of the scattered spots in arch rib that are close to the pressure line. Then by using the method of curve fitting,several(polynomials) of each degree that can be obtained and applied in engineering,and a most appropriate arch bridge axis is identified through comparison.At last,tow instances of practical engineering work are given,and the results show that the arithmetic brought forward in this paper reduces the biased error between arch bridge axis and pressure line,and improves the state of bending of arch rib.