Based on the deep foundation pit project at the entrance of Tianjin Airport Tunnel No.1 on the Beijing-Binhai Intercity Railway,an optimized scheme of traditional steel support replacement with a new type of lattice truss support was proposed.The differences in construction mechanical response between the two conditions were compared and analyzed through numerical research.The engineering application was carried out to verify the rationality of the optimized scheme.The results show that,compared with steel support,the lattice truss scheme does not require side wall embedded parts,which can avoid leakage problems caused by wall repair and preloading damage,and is more conducive to later demolition.Although the strength and stiffness of the lattice truss are weaker than those of the steel support,the lateral displacement,surface settlement and internal support force do not exceed the allowable limitation,and the safety factors are all above 2.0.Through engineering practice,it has been verified that using lattice truss is safe and feasible,which can not only significantly reduce the construction period but also save cost.
关键词
深基坑/钢换撑/格构桁架/数值模拟/现场实测
Key words
deep foundation pit/steel support replacement/lattice truss/numerical simulation/field monitoring
维普
万方数据