Abstract

The objective of this study was to overcome the shortcomings of the current analysis and calculation methods of the spatial bar system model, plane beam grillage model and solid element model in the design of the box-girder bridge. For example, the spatial bar system model lacks refined analysis of spatial effects, such as the shear lag effect, effective distribution width problem, and eccentric load coefficient problem. The similarity of the plane beam grillage model on the principle of equivalence cannot accurately reflect the shear stress distribution of the box-shaped composite beam and the local force on the top and bottom plates. The solid element and shell element models cannot directly calculate the internal force of the cross section. The calculation efficiency is low, and it is difficult to combine with the overall calculation. This paper proposes a spatial grid element analysis model suitable for fine analysis of box-girder bridges, which has the completeness and reliability of the analysis results and makes up for the shortcomings of the current box-girder bridge analysis methods. Firstly, the stiffness matrix of the spatial grid element is deduced, and the analysis program of the combined box girder based on the spatial grid element is written using MATLAB software. Then an actual calculation example is analyzed, and the difference between the calculation result of the spatial grid element and the result of the literature is compared and analyzed. The correctness and applicability of the spatial grid element model is verified.

摘要

本研究的目的是克服目前箱梁桥设计中空间杆系模型、平面梁格架模型和实体单元模型分析计算方法的不足。例如，空间杆系统模型缺乏对空间效应的精细分析，如剪力滞效应、有效分布宽度问题、偏载系数问题等。平面梁格架模型基于等价原理的相似性不能准确反映箱形组合梁的剪应力分布和顶、底板的局部受力。实体单元和壳单元模型不能直接计算横截面的内力。计算效率低，难以与整体计算结合。本文提出了一种适用于箱梁桥精细分析的空间网格单元分析模型，具有分析结果的完整性和可靠性，弥补了现有箱梁桥分析方法的不足。首先推导了空间网格单元的刚度矩阵，并利用MATLAB软件编写了基于空间网格单元的组合箱梁分析程序。然后分析了一个实际计算实例，比较分析了空间网格单元的计算结果与文献结果的差异。验证了空间网格单元模型的正确性和适用性。具有分析结果的完整性和可靠性，弥补了现有箱梁桥分析方法的不足。首先推导了空间网格单元的刚度矩阵，并利用MATLAB软件编写了基于空间网格单元的组合箱梁分析程序。然后分析了一个实际计算实例，比较分析了空间网格单元的计算结果与文献结果的差异。验证了空间网格单元模型的正确性和适用性。具有分析结果的完整性和可靠性，弥补了现有箱梁桥分析方法的不足。首先推导了空间网格单元的刚度矩阵，并利用MATLAB软件编写了基于空间网格单元的组合箱梁分析程序。然后分析了一个实际计算实例，比较分析了空间网格单元的计算结果与文献结果的差异。验证了空间网格单元模型的正确性和适用性。利用MATLAB软件编写了基于空间网格单元的组合箱梁分析程序。然后分析了一个实际计算实例，比较分析了空间网格单元的计算结果与文献结果的差异。验证了空间网格单元模型的正确性和适用性。利用MATLAB软件编写了基于空间网格单元的组合箱梁分析程序。然后分析了一个实际计算实例，比较分析了空间网格单元的计算结果与文献结果的差异。验证了空间网格单元模型的正确性和适用性。