竖向荷载作用下曲线梁桥约束反力特性分析

Analysis of Restraint Reaction Force Characteristics of Curved Beam Bridges Under Action of Vertical Load

为分析竖向荷载作用下曲线梁桥约束反力的特性,以力法方程、三弯矩方程为基础,推演单跨曲线梁桥和连续曲线梁桥的约束反力(扭矩)表达式,并采用推导出的表达式和有限元程序PCBP分别对某六跨连续曲线梁桥的内力与约束反力进行计算分析。分析结果表明:在点支承抗扭约束条件下,受竖向荷载作用的单跨曲线梁桥,其曲线内侧的约束反力小于曲线外侧的;受竖向荷载作用的连续曲线梁桥,梁端曲线内侧的约束反力小于曲线外侧的,而在中间支承处会出现曲线内侧的约束反力大于曲线外侧的现象。

To analyze the restraint reaction force characteristics of curved beam bridges under the action of vertical load,the expressions for the restraint reaction forces（torsional moment） of the single-span curved beam bridge and continuous curved beam bridge are deduced on the basis of the force method equation and three-moment equation.The internal force and the restraint reaction force of a 6-span continuous curved beam bridge are respectively calculated and analyzed by the deduced expressions and finite element program PCBP.The results of the analysis show that under the point-supported torsional resistant conditions,for the single-span curved beam bridge subjected to vertical load,the restraint reaction force in the inner side of the curved beam is less than that in the outer side while for the continuous curved beam bridge subjected to vertical load,the restraint reaction force in the inner side of the curved beam at the beam end is less than that in the outer side,however,the restraint reaction force in the inner side of the curved beam at the intermediate support may be greater than that in the outer side.