独墩单支座混凝土连续箱梁超重车辆偏载工况分析

摘要

连续处采用独墩单支座支承的混凝土连续箱梁是高速公路立交区匝道桥、跨线桥和城市高架桥较为常用的一种结构形式，但该结构存在横向抗倾覆稳定性不足和扭矩内力累增集中的问题。近年来，公路运输违规超载的车辆屡屡出现，在极端情况下还会无意中形成重车车队且均靠桥面最外侧的慢车道行驶，这对易发生重车堵车现象的进出立交匝道桥出现的概率更大。本文按照某高速公路实际统计的超载车辆按几种极端的情况分别对其立交区典型的独墩单支座支承的混凝土连续箱梁桥进行梁体横向稳定性和强度的分析研究，以寻求其在超载作用下的薄弱环节，为今后该类桥梁的设计和运营管理提供参考和建议。%The concrete continuous box girder supported by the single-column pier and single bearing is often used as a structure of a priority for interchange ramp bridge, overpass bridge in expressway and viaduct in city. But the kind of structure itself has the characteris-tics of insufficient transverse overturning stability resistance and torque increasing intensively. Overloading road irregularities on highway of-ten appeared in recent years, as the certain extreme cases a heavy truck fleet inadvertently forms and drives on the most outer lane of the bridge deck, This kind of situation is more likely to occur on interchange ramp bridge for traffic jams. In this paper, under the load of sev-eral kinds of overloading vehicles fleet according to the statistics of an expressway, the type of the structure in interchange area is analyzed to seek the weak link under the action of a overload and to provide some reference and the suggestion for the design and operation manage-ment of this type of bridges in future.