考虑拼装误差影响的轨道交通地下车站装配式轨顶风道力学特性研究

Assembly Error Influence on Mechanical Characteristics of Prefabricated Roof Air Duct of Interval Tunnel in Rail Transit Underground Station

为掌握拼装误差对轨道交通地下车站装配式轨顶风道力学特性的影响,采用有限元数值模拟,选取无拼装误差、2 mm误差、5 mm误差、10 mm误差4种情形,研究了存在拼装误差的装配式轨顶风道力学性能变化。结果表明:无拼装误差装配式轨顶风道应力呈对称分布,且混凝土拉应力较小,变形曲线与现浇轨顶风道相似,最大竖向变形出现于风道底板中部;存在拼装误差、无误差的轨顶风道应力分布一致,且较小拼装误差轨顶风道应力水平大于较大误差轨顶风道。此外,拼装误差对装配式轨顶风道变形与受力的影响均较小,可以满足使用安全要求。研究成果可为预制装配技术在地铁车站装配式二次结构建设中的应用提供参考。

In order to know the influence of assembly error on the mechanical characteristics of prefabricated roof air duct of interval tunnel in rail transit underground station, the mechanical performance of prefabricated roof air duct with assembly errors were studied by finite element numerical simulation. Four prefabricated roof air ducts were selected including the one without assembly error, the one with 2 mm error, the one with 5 mm error and the one with 10 mm error. The results showed that: the prefabricated roof air duct without assembly error is featured with the symmetrical stress distribution, and small concrete tensile stress;its deformation curve is similar to that of the cast-in-place roof air duct, and the maximum vertical deformation occurs in the middle of air duct slab. The stress distribution of the roof air duct with assembly error is in consistent with that of the roof air duct without assembly error. And the stress of roof air duct with small assembly error is greater than that of the air duct with large assembly error. In addition, all of the prefabricated roof air ducts can meet the safety requirements since the assembly error has little influence on the deformation and stress of the prefabricated roof air duct. The study results provide reference for the application of prefabricated assembly technology in the construction of prefabricated secondary structure of subway station.