【作者】 吴文明；

【导师】 余诗泉；

【作者基本信息】 东北林业大学 ， 道路与铁道工程， 2004， 硕士

【副题名】斜弯桥梁格结构有限元程序的编制

【摘要】 梁格分析法是用计算机分析桥梁上部结构比较实用有效的空间分析方法，它具有基本概念清晰、易于理解和使用等特点，因此在桥梁结构分析中得到了广泛的采用。它是将结构原型模拟成便于计算机分析的等效梁格，通过对等效梁格的分析，得到结构原型的力学性能和内力情况。梁格法的主要思路是将上部结构用一个等效梁格来模拟，将分散在板式或箱梁每一区段内的弯曲刚度和抗扭刚度集中于最邻近的等效梁格内，实际结构的纵向刚度集中于纵向梁格构件内，而横向刚度则集中于横向梁格构件内。 本文是利用梁格法对斜弯桥空间结构进行分析，文中探讨了斜弯桥上部结构的力学性能，板式、梁板式及箱梁截面上部结构的网格划分与相应截面特性的计算方法，以及考虑各种预应力损失，通过等效荷载计算预应力束的总效应。在分析过程中，作为一种新的尝试，本文采用MATLAB语言来实现梁格结构的有限元法分析、空间预应力效应的计算，由于该软件具有强大的矩阵计算功能，利用一般的符号和函数就可以对矩阵进行加、减、乘、除的运算以及转置和求逆运算，而且可以处理稀疏矩阵等特殊的矩阵，非常适合于有限元等大型数值算法的编程，因而极大地提高了编程效率与结果的准确性。更多还原

【Abstract】 The beam grid analysis method is more practical and more effective than others in space structure which uses computer means to analyze top structure of bridge. Because it has the feature that its basic conception is legible and is easy to understand and to use, used widely in bridge structure analysis. The method simulates the structure with equivalent beam grid that is easy for the analysis of computer, and by the analysis of the equivalent beam grid the mechanical characteristics and internal stress can be obtained. The main way of the method of beam grid is to simulate the top structure with a equivalent beam grid, and concentrates the scattered bending rigid and tension rigid in slab or box beam into the close equivalent beam grid, and the longitudinal rigid of the real structure is concentrated in longitudinal beam rigid, and the lateral rigid is concentrated in lateral beam rigid.The thesis probes into space structure of oblique and curved bridge with beam grid method. It is discussed in the thesis about mechanics capability of top structure of oblique and curved bridge and how to divide grid and calculate its section attribution of shell, beam-shell, box beam’s top structure, and calculates the total effect of pre-stressed bunch, considering all kinds of the lost of pre-stress. In the course of analysis, as a new attempt, the thesis uses MATLAB language to carry out finite element method of beam grid structure and calculate space pre-stress force. Because of the powerful function of matrix’s calculation, the procedure utilizes normal signs and functions to plus, subtract, multiply, divide, transpose and inverse matrix, and can handle special matrix such as the sparse matrix, and is suitable for the programming of the large-scale numerical algorithm of finite element. So it advances efficiency of programming and precise of result extremely.更多还原