中文摘要：

波形钢腹板组合箱梁扭转刚度与混凝土箱梁相比更弱,因此针对波形钢腹板组合箱梁的扭转动力性能的研究非常必要。以自振状态下的波形钢腹板组合箱梁微段为研究对象,考虑了横隔板对截面纵向纤维变形的约束,建立了约束扭转条件下的动内力平衡方程,依据乌曼斯基扭转理论以及波形钢腹板的力学性质推导得出了波形钢腹板组合箱梁在约束扭转条件下的振动微分方程;并根据简支梁的约束条件,求得了扭转振动方程的理论解。通过分别采用理论抗扭刚度与规范抗扭刚度求解扭转频率发现：约束扭转产生的翘曲应力对自振扭转频率的影响随着跨度的增大而减小;计算结果与数值模型试验结果对比分析得出：频率计算公式在跨度10 m~40 m范围内是具有较高的精度,可以用于波形钢腹板组合箱梁的扭转分析。

英文摘要：

The corrugated steel web composite box girder, which the torsional stiffness is much smaller than the con- crete box-girder, so is necessary that getting a good understanding of the corrugated steel web composite box girder＇ s torsional dynamic performance. To build the dynamic internal forces equilibrium equation under restrained torsional vibration, the paper takes the infinitesimal element of composite beam with free vibration as a topic object in re- search, taking a full consideration of constrained lengthways deformation from the diaphragm girder. The differential equation of free vibration with the restrained torsion comes from the dynamic equation, according to the theory of Umansky. And then it will get the solution of the equation from the constraint condition of the simply supported beam. It is an observation getting from the comparison that the span of the bridge get longer and the effect of warp stress for the frequency get smaller. At last, it is found that the analysis in the paper is correct and more precise and can be used for the torsion analysis of corrugated steel web composite box girder in a certain span of 10 m -40 m.