均匀温度下多跨半刚接整体桥受力性能

Mechanical performance of multi-span semi-rigid integral bridge under uniform temperature

以某多跨空心板梁桥改造为半刚性节点整体桥为例,建立考虑桩-土相互作用的桥梁有限元实体模型,进行上、下部结构不同连接方式对温度变化作用下结构受力性能影响分析.结果表明:主梁与桥台连接方式对整体桥受力的影响大于主梁与桥墩处的连接方式;主梁与桥台刚接时,在温度变化作用下,结构内产生的附加轴力、弯矩远大于主梁与桥台采用半刚接的.对半刚性节点进行参数分析,结果表明,橡胶套壁厚是影响主梁弯矩的主要因素,橡胶垫及钢棒直径对主梁弯矩影响较小;橡胶套壁厚和钢棒直径对桥台处柱-桩基的影响较大,对桥墩处柱-桩基弯矩影响较小,可忽略不计.

Based on a semi-rigid integral retrofitted bridge,which is a hollow slab beam bridge with multi-spans,finite element solid model was established considering the interaction between pile and soil,and its mechanical performance under temperature changes was studied,taking the connection types between the superstructure and substructure as the key parameter.Analysis results show that the connection type between main beam and abutment has larger influence on internal forces of integral bridge than that of the connection type between main beam and pier.Addition axial forces and bending moments of structure with rigid connection between main beam and abutment are much larger than those with semi-rigid joint connection.Parameters analysis on semi-rigid joint show that the wall thickness of rubber sleeve is the main factor affecting the bending moment of main beam,while the thickness of rubber pad and diameter of steel bar have very small effect;the wall thickness of rubber sleeve and diameter of steel bar have very great effect on bending moment of pier-pile foundation at the abutment,while the thickness of rubber pad and diameter of steel bar have very small effect on bending moment of pier-pile foundation at the pier and are negligible.