大直径盾构隧道上层预制车道结构传力分析

Analysis on Force Transfer of Upper Prefabricated Lane Structure in Large-diameter Shield Tunnel

摘要:

随着盾构隧道技术以及装配式建筑的发展与成熟，大直径盾构隧道内部采用全预制双层结构逐步成为一种趋势。依托漕宝路快速路新建工程，采用MIDAS Civil软件建立考虑加载过程的上层预制车道结构模型，对上层预制车道结构传力特征进行分析。研究表明：分阶段加载对上层预制车道结构受力影响显著，进行预制车道板结构设计时，采用一次性加载计算结果将导致设计偏不安全；与车道板共同预制的纵梁受弯剪扭复合作用，纵梁中部约束弱，应力主要集中于柱端附近；车道板-板间后浇湿接头对于协调相邻车道板间的受力和变形效果明显。

Abstract:

With the development and maturity of shield tunneling and fabricated architecture technology, the full prefabricated double-layer structure in large-diameter shield tunnel gradually becomes a trend. Relying on the newly built Caobao Road Expressway Project, the upper prefabricated lane structure model considering the loading process is built by using the software Midas Civil to analyze the force transfer characteristics of the upper prefabricated lane structure. The research shows that the effect of stage loading on the stress of the prefabricated lane structure on the upper layer is significant. In the design of prefabricated lane slab structure, using one-time loading results will lead to unsafe design. The longitudinal beam prefabricated with the lane slab is subjected to the combined action of bending, shear and torsion, and the central constraint of the longitudinal beam is weak. And the stress is mainly concentrated near the column end. The post-poured wet joint between the lane slabs has obvious effect on coordinating the stress and deformation between the adjacent lane slabs.