Abstract:In order to achieve the intensive land use, the large-scale complex construction projects integrating subways, utility tunnels and underground space development are gradually increasing. The design of these projects is more difficult because of a complex structure, a wide range of involvement and many constraints. Consequently, it is necessary to explore the design approaches and engineering experience from the completed analogous projects so as to provide a reference for the similar project in the future. Taking the underground public corridor and supporting facility project in the central axis area of Wuhan Optics Valley as an example, the main characteristics of its structures and the design principle of pile foundation type selection are analyzed, and the feasibility of seismic design for reconstructed structures, the advantages of active anti-floating design and the methods for controlling cracks in super-long structures are expounded. The conclusion is that for cast-in-place piles with long empty pile sections and short effective pile lengths, and the use of double-sleeve test piles can improve the accuracy of test piles. It is feasible to conduct the seismic design for reconstructed structures by using a simplified analysis method superimposing the reaction spectrum method and the reaction displacement method. Compared with the traditional anti-uplift pile and load-bearing anti-floating design, the use of active anti-floating scheme can significantly shorten the construction duration and reduce the cost under the suitable geological conditions. The temperature stress of ultra-long structures is calculated. By configuring the reinforcing bars based on the calculation results and comprehensively considering the structural measures, the occurrence of cracks can be well controlled.
