地下大跨度隧道结构截面受力特性及经济分析

Analysis on Mechanical Behavior and Economic Efficiency of Structural Cross-sections of Underground Long-span Tunnel

摘要:

随着大跨度隧道建设的增多，各结构形式的横截面是否适用、经济是否合理有待进一步研究分析。常见大跨度隧道横截面形式主要包括矩形框架结构、轻型框架结构、折板拱形结构。以某下穿晋江隧道为背景，研究隧道主线在10 m覆土，17.6 m净跨下，不同截面形式的受力特点，并进行经济性分析。研究发现：对比矩形框架结构，轻型框架及折板拱形结构的弯矩及偏心率整体呈现减小趋势；轻型框架混凝土用量可节省14%；折板拱形结构节省混凝土为21%，采用轻型框结构及折板拱形结构更为经济合理。

Abstract:

With the increase in the construction of long-span tunnels, it is necessary to further study and analyze the applicability and economic rationality of various structural cross-sectional forms. The traditional cross-sectional forms of long-span tunnels mainly include the rectangular frames, lightweight structures and folded-plate arched structures. With a tunnel crossing the Jinjiang River as the background, the mechanical behavior of different cross-sectional forms of the main line of the tunnel under 10 m of soil cover and 17.6 m of clear span is studied, and an economic analysis is conducted. The study finds that compared with rectangular frame structures, both lightweight frame and folded-plate arched structures show a decreasing trend in bending moments and eccentricity. The amount of the lightweight frame concrete can be saved by 14%, and the concrete of folded-plate arched structure can be saved by 21%. The use of the lightweight frame and folded-plate arched structures are more economically reasonable.