钻爆法双线铁路隧道预制拼装二次衬砌分块方式研究

Study on the Partition Mode of Prefabricated and Assembled Secondary Lining of Double-track Railway Tunnels by Drilling and Blasting Method

  • 摘要: 针对钻爆法施工隧道二次衬砌采用模筑混凝土衬砌时其施工速度慢且拱部衬砌质量难以达到设计要求等问题,提出适用于钻爆法施工的双线铁路隧道预制拼装二次衬砌结构分块方案。基于盾构法隧道管片接头的计算理论,计算得到预制二次衬砌横向和纵向接头的刚度值。利用梁-弹簧计算模型对不同分块方案进行对比和分析,研究不同厚度拼装衬砌的受力特性,提出较优的拼装二次衬砌厚度为500 mm。同时采用壳-弹簧计算模型对不同幅宽的通缝拼装二次衬砌内力分布进行了分析,结果表明,预制拼装二次衬砌内力分布具有明显三维特性,接头边缘部位弯矩较大,而中部弯矩较小,拼装二次衬砌的幅宽宜为2.0 m。

     

    Abstract: When the cast-in-situ concrete is used for the tunnel secondary lining constructed by the drilling and blasting method, the construction speed is slow and the arch lining quality is difficult to meet the design requirements. So a partition scheme of prefabricated and assembled secondary lining structure is proposed for the doubletrack railway tunnels constructed by the drilling and blasting method. The stiffness values of transverse and longitudinal joints of prefabricated and assembled secondary lining are calculated on the basis of the calculation theory on segment joints of shield tunnels. Then, the beam-spring calculation model is used to compare and analyze different lining partition schemes, study the stress characteristics of prefabricated and assembled lining with different thickness and determine that the optimal thickness of prefabricated and assembled secondary lining is 500 mm. Meanwhile, the shell-spring calculation model is adopted to analyze the internal force distribution of prefabricated and assembled secondary lining with straight joints and different widths. The results show that the internal force distribution of prefabricated and assembled secondary lining has obvious three-dimensional characteristics, the bending moment is large at the edge of the joint, but small in the middle, and the width of prefabricated and assembled secondary lining should be 2.0 m.

     

/

返回文章
返回