基于辅助轨道的多支点转体桥施工关键技术研究

Research on Key Techniques for Construction of Multi-fulcrum Turning Bridge Based on Auxiliary Track

为解决转体桥两端长度和自重差异大,难以采取常规配重平衡的问题,在梁底长臂端设置带有齿轮辅助支撑的环形滑道,在梁面设置索塔及临时拉索,形成基于辅助轨道的多支点转体桥施工技术.实施结果表明,转体梁段前支点截面处应力沿横截面大致均匀分布,腹板处应力最大(126.65 MPa),翼缘处应力较小;悬臂端最大挠度为12.76 cm,应力和挠度均与理论值接近,且在材料性能允许范围内.该类转体方法结构稳定、受力清晰,可为类似特殊梁段的转体提供参考.

In order to solve the problems that the length and weight of the two ends of the swivel bridge are large and it is difficult to adopt conventional counterweight balance,an annular slideway with gear auxiliary support is provided at the long arm end of the beam bottom,and a tower and temporary cables are provided on the beam surface.The construction technology of multi-fulcrum swivel bridge based on auxiliary track is formed.The implementation results show that the stress at the front fulcrum section of the swivel beam is distributed uniformly along the cross section,the stress at the weh is the largest(126.65 MPa),and the stress at the flange is relatively small.The maximum deflection of the cantilever end is 12.76 cm,both the stress and the deflection are the same as the theoretical value and within the allowable range of material properties.This type of swivel method has a stable structure and cleai-stress,and can provide reference for the swivel similar to a special beam section.