公路隧道装配式仰拱拼装设备与工艺初步研究

Preliminary Study on Equipment and Techniques for Installing Prefabricated Inverted Arches in Highway Tunnels

摘要: 本文针对钻爆法公路隧道现浇仰拱施工效率低、质量控制难的问题，设计了一种装配式仰拱拼装设备并提出了配套施工工艺。通过三行车梁与单行车梁方案的技术经济对比，确定采用单梁门式框架与轨道行走系统方案。建立设备力学模型开展多工况静力学有限元分析，明确了各关键构件的应力分布与变形特性。以安全系数不低于2.0、最大变形量不大于10 mm为设计准则，确定了构件尺寸与材料选型，其中框架下梁安全系数2.02，最大变形量9.99 mm。施工工艺涵盖基底垫层处理、预制块吊装就位、预应力张拉及拱底注浆等环节。该设备在拼装期间可保持隧道中部通行，对初期支护无额外要求，为钻爆法公路隧道装配式仰拱施工提供了技术参考。

Abstract: This paper dens a prefabricated invert assembly equipment and proposes a corresponding construction process to solve the low efficiency and difficult quality control of cast-in-place invert construction in drill-and-blast highway tunnels. The single-beam gantry frame with rail traveling system is selected after comparing the three-beam and single-beam schemes. A mechanical model is built and static finite element analysis under multiple working conditions is performed, showing the stress distribution and deformation characteristics of key components. With the design criteria of safety factor not less than 2.0 and maximum deformation not greater than 10 mm, the component dimensions and material types are determined. The safety factor of the lower frame beam is 2.02 and the maximum deformation is 9.99 mm. The construction process includes base cushion treatment, prefabricated block hoisting and positioning, prestressed tensioning, and invert grouting. The equipment maintains passage through the tunnel center during assembly and imposes no extra requirement on the primary support, providing a technical reference for prefabricated invert construction in drill-and-blast highway tunnels.