独柱支承梁式桥倾覆稳定性验算方法研究

Study of Checking Method for Overturning Stability of Beam Bridge Supported by Single-Column Pier

为减少独柱支撑匝道桥倾覆事故的发生,对该类桥梁倾覆稳定性验算方法进行研究。根据结构及受力特点,对独柱支承梁式桥进行分类,以北京市此类桥梁为背景,研究该类桥梁倾覆稳定性。研究结果表明,中墩固结独柱支承梁式桥倾覆破坏为构件强度破坏;中墩铰结独柱支承梁式桥倾覆破坏首先表现为边支座脱空,然后出现中墩支座转角超限,最终发生结构倾覆的本质特征,据此制定出了适用于验算独柱支承梁式桥倾覆稳定性的方法,可供同类桥梁的设计及维修加固参考。

In order to reduce the risk of the overturning of ramp bridge supported by single- column piers, the checking method for the overturning stability of the bridge of such type was studied. The beam bridge supported by single-column piers was classified according to its struc- tural feature and corresponding mechanical behavior, and the overturning stability was studied against the background of bridges of such type in Beijing. The results of the study indicate that the overturning damage to the beam bridge supported by single-column piers fixed to the beam be- longs to the failure of strength loss of the components; while the overturning damage to the beam bridge supported by single-column piers hinged to the beam undergoes three steps, first, the side bearing is hanging in the air, then the rotation degree of the bearing on the intermediate pier sur- pass the limited value, and finally the structure overturned. Based on the results of the study, the method suitable for checking the overturning stability of the beam bridge supported by singlecolumn piers is figured out, which can provide references for the design and maintenance of the bridge of the same type.