波形钢腹板曲线箱梁的空间力学行为及一维梁段分析方法研究

The curved box girder with corrugated steel webs is an innovative composite structure, and its spatial mechanical behavior analysis is neccessary. Theoretical, numerical and experimental studies are conduct to investigate the spatial mechanical behavior of curved box girder with corrugated steel webs, with establishing of one-dimensional beam segment analysis method. Firstly, the uncoupled behaviors of flexure, torsion and distortion of straight box girder with corrugated steel webs are explored to reveal their mechanism. Then, the unified theory model for bending analysis is presented based on comparison and analysis for the existing five kinds of bending theory with great difference. Meanwhile the unified theory models for torsion and distortion analysis are presented, by introducing the structure characters of straight box girder with corrugated steel webs into the unified theory models for the conventional thin-walled straight box girder, which is previously developed. Furthermore, based on the above three unified theory models, and sufficiently considering initial curvature, coupling effect and mechanical characteristics of curved box girder with corrugated steel webs, the spatial analysis theory is established by using the generalized coordinate principle and the mixed variational principle. An one-dimensional beam segment element is presented for analyzing the spatial mechanical behavior of curved box girder with corrugated steel webs, including tension, shear, torsion, distortion and their mutual couplings. The accuracy and validity of the proposed method will be verificated by comparing with the model tests. The achievement will contribute to the advancement of curved box girder with corrugated steel webs.

波形钢腹板曲线箱梁是一种新型组合结构，其空间力学行为的分析方法亟待解决。本课题拟通过理论研究、仿真分析和模型试验，探究其空间力学行为特性，建立其一维梁段分析方法。首先分别探明波形钢腹板直线箱梁的弯曲、扭转和畸变三种力学行为；然后，对其现存五种典型弯曲理论进行对比研究，综合提出其弯曲分析的统一理论模型；并基于前期研究得出的传统薄壁箱梁扭转和畸变分析的统一理论模型，引入波形钢腹板直线箱梁的结构特征，拓展建立其扭转和畸变分析的统一理论模型；最后，基于这三个统一理论模型，充分考虑波形钢腹板曲线箱梁的初始曲率、耦合效应及力学特征，采用广义坐标法和混合变分原理，建立波形钢腹板曲线箱梁空间力学行为的整体分析理论，提出能同时考虑拉压、弯曲、剪切、扭转、畸变及其耦合作用的一维有限梁段单元分析模型，并通过模型试验校验理论计算结果。研究成果可为波形钢腹板曲线箱梁的工程应用和发展提供重要理论依据。

波形钢腹板曲线箱梁应用广泛，其空间力学行为的分析方法制约其进一步推广。本课题通过理论研究、仿真分析和模型试验，探究其空间力学行为特性，建立其一维梁段分析方法。首先分别探明波形钢腹板直线箱梁的弯曲、扭转和畸变三种力学行为；然后，对其现存五种典型弯曲理论进行对比研究，提出基于三角级数的弯曲分析理论模型；并基于前期研究得出的传统薄壁箱梁扭转和畸变分析的统一理论模型，引入波形钢腹板直线箱梁的结构特征，拓展建立基于三角级数的扭转和畸变分析理论模型；最后，基于这三个理论模型，充分考虑波形钢腹板曲线箱梁的初始曲率、耦合效应及力学特征，建立波形钢腹板曲线箱梁空间力学行为的整体分析理论，提出一维有限梁段单元分析模型，并通过设计模型试验校验理论计算结果。研究成果可为波形钢腹板曲线箱梁的工程应用和发展提供重要理论依据。