基于UHPC的内衬非开挖加固新方法及试验

New Method and Experiment for Trenchless Reinforcement of Inner Lining Based on UHPC

摘要:

为解决老旧砖砌排水拱涵非开挖结构性修复中施工效率低和耐久性不足的问题，以长沙市某渠修复工程为依托，提出一种基于超高性能混凝土（ultra-high performance concrete， UHPC）预制内衬的非开挖加固新方法。对比分析不同材料及节点连接方式的力学性能，并开展UHPC材料与拼装节点的模型试验及现场试验研究。UHPC 构件在抗裂性能和极限承载能力方面显著优于普通混凝土；曲螺栓连接在承载力、延性及节点安全储备方面表现最优；预制内衬结构随时间逐步参与受力，新旧结构可形成有效共同工作。该研究可为城市排水拱涵非开挖修复的工程设计与施工提供参考。

Abstract:

To address the issues of low construction efficiency and insufficient durability in the trenchless structural repair of old brick-built drainage arch culverts, relying on a restoration project of a certain canal in Changsha City, a new trenchless reinforcement method based on ultra-high performance concrete (UHPC) prefabricated linings is proposed. The mechanical performances of different materials and joint connection methods are comparatively analyzed, and the model tests and on-site experiments of UHPC materials and assembled joints are conducted for research. UHPC components are significantly superior to ordinary concrete in terms of crack resistance and ultimate load-bearing capacity. The curved bolt connection performs the best in terms of bearing capacity, ductility and safety reserve of the joint. The prefabricated inner lining structure gradually participates in the force over time, and the new and old structures can work effectively together. The research result can provide a reference for the engineering design and construction of trenchless renovation of urban drainage arch culverts.