基于 UHPC 的隧道节点改造结构体系方案研究

Research on Structural System Scheme of Tunnel Node Reconstruction Based on UHPC

摘要:

超高性能混凝土（Ultra High Performance Concrete,UHPC）是一种高强度、高耐久性的新型建筑材料，具有优异的力学性能和耐久性，在隧道及桥梁工程中得到广泛应用。在隧道工程领域，其已成功应用于盾构隧道管片加固、隧道衬砌、防火涂料和隧道门洞等部位，采用UHPC结构将隧道U形槽改造为闭口断面还鲜有案例。以白鹅潭大道隧道节点改造为依托，受隧道净空限制，通过对常规混凝土、工字钢、UHPC结构比较分析，提出无筋UHPC连续梁加现浇板体系结构，满足了结构附加自重小、抗疲劳性能强、耐久性好等需求。UHPC改造U形槽具有很好的轻型化、高承载力、经济性优和景观效果好的优点。

Abstract:

Ultra-high performance concrete (UHPC) is a new type of building material with high strength and durability, which has excellent mechanical properties and durability, and is widely used in tunnel and bridge engineering. In the field of tunnel engineering, it has been successfully applied to the reinforcement of shield tunnel segments, tunnel lining, fireproof coatings, and tunnel openings. There are few cases of using UHPC structures to reconstruct U-shaped grooves into closed sections of tunnels. Based on the node reconstruction of the Baietan Avenue Tunnel, limited by the tunnel clearance, through comparative analysis of conventional concrete, I-steel, and UHPC structures, a non-reinforced UHPC continuous beam plus cast-in-place slab system structure is proposed to ensure the requirements of small additional dead weight, strong fatigue resistance and good durability of the structure. The U-shaped groove reconstructed by UHPC has the good lightness, high bearing capacity, economy and landscape effects.