混凝土简支斜交箱型梁桥受力特性分析

为了深入分析简支斜交箱型梁桥的力学性质，研究其空间受力特点，以斜交角度为30°的简支斜交箱梁桥为背景，基于梁格法，建立了直桥有限元模型和斜桥有限元模型，对比分析了直桥与斜桥的支座反力、变形和主梁内力。研究结果表明：斜桥锐角处的支反力小于直桥，钝角处的支反力远大于直桥；斜桥出现明显的平面转动现象，表现为桥面整体在支承边处钝角方向往锐角方向转动；斜桥边梁的最大扭矩是直桥的2.06倍，增加斜桥箱梁腹板厚度和加密受扭箍筋对其抗扭能力有较大的提升作用。本文研究成果可为简支斜交箱型梁桥的受力性能研究和同类工程设计提供参考。

Analysis for Mechanical Characteristics of concrete simply supported skew box girder bridge

In order to analyze the mechanical properties of simply-supported skew box girder bridge and study its spatial force characteristics, a simply-supported skew box girder bridge was taken as the background, with skew angle 30°. Based on the grillage method, the finite element model of straight bridge and skew bridge were established. The reaction forces, deformations and internal forces of main girder of straight bridge and skewed bridge were compared and analyzed. The results show that: the reaction force at the acute angle of the skew bridge is smaller than that of the straight bridge, and the support reaction force at the obtuse angle is much larger than that of the straight bridge. Obvious plane rotation phenomenon which manifesting as the overall rotation of the bridge deck in the direction of the obtuse angle to the acute angle at the supporting edge was showed in the skew bridge. The maximum torque for side beam of the skew bridge is 2.06 times that of the straight bridge. The torsional capacity of the skew bridge box girder can be greatly improved by increasing the web thickness and encrypting the stirrups. The research results can provide reference for the study of the force performance of simply-supported skew box girder bridge and the design of similar engineering.