斜交梁桥受力特性及设计研究

Mechanical Characteristics and Design Research of Skew Bridge

支承方式对桥梁结构的受力性能具有重要影响。与常规的正交支承桥梁结构不同,斜交支承条件下,桥梁结构表现出许多特殊的受力规律:由于弯扭耦合作用,在两端附近梁端内有较大负弯矩产生,支座反力不均匀,甚至会出现负拉力现象;在竖向荷载作用下,作为下部结构的桥台,也会表现出特有的受力特点,影响荷载较上部结构更加复杂。在分析了上部结构受力特性后,整体建模,分析了主梁和桥台的受力效应。研究了整体斜交角影响下的正交与斜交作用效应对比和桥台斜交角影响下的斜交梁桥作用效应对比。依据上述两种情况的对比分析结果,为斜交梁桥的上部结构设计以及桥台、桥墩设计提供科学的技术指导。

Supporting scheme has important influence on mechanical properties of bridge structure. Thebridge structure performance has many special bearing law at oblique supporting conditions and is different with conventional orthogonal supporting way： because of bending-torsion coupling effect, the larger negative moment appears at the ends of the girders, and support reaction is not uniform, even negative tension appears; as the sub structure, the abutment can exhibit unique mechanical characteristics under the vertical load, its influence on load is more complex than the superstructure. After analyzing the mechanical behavior of superstructure, the stress effect of main girder and the abutment is analyzed by modeling. Then the paper contrasts the orthogonal and oblique influence effect under overall oblique angle and the influence effect of skew bridge under oblique angle of the abutment. Based on the contrast analysis result of the above two situation, it provides scientific and technical guidance for superstructure design the abutment pier, and pier design of the skew girder bridge.