外部约束失效对桥梁结构强健性影响分析

Analysis on the Influence of External Constraint Failure on the Robustness of Bridge Structure

目前桥梁设置的外部约束较少,多数桥梁仅考虑了挡块,而因缺少规范支撑,许多桥梁设置的挡块尺寸偏小,其防落梁能力难以评估,对于中间为单支座的连续梁桥已经多次出现桥梁倾覆的事故,本论文以某4 m×22 m钢筋混凝土连续梁桥为算例,利用利用ANSYS建模分析,以能量法分析“外部约束”失效对连续梁的影响,分析表明,若梁端处侧的竖向约束失效将导致桥梁出现倾覆,应采取有效的措施在连续梁中墩位置增设抗扭约束。

At present,there are few constraints set by bridges,and most bridges only consider blocks.Due to the lack of standardized supports,many bridges set blocks with small sizes,and their ability to prevent falling beams is difficult to evaluate.Continuous girder bridges have had many overturning accidents.This paper takes a 4 m×22 m reinforced concrete continuous girder bridge as an example,uses ANSYS modeling analysis,and uses energy method to analyze the influence of“external restraint”failure on continuous girder.The analysis shows that If the vertical restraint on the side of the beam end fails,the bridge will overturn,and effective measures should be taken to add torsional restraint at the pier position in the continuous beam.