Abstract:Abstract : Research purposes : Based on a practical example of No. 4 entrance of Wuhan Metro line 3, under the complex environmental conditions with dense first terrace of Yangtze River,pipelines and construction in Wuhan, the regulation of measured data of the settlement of the surface transverse and longitudinal section and the elevated highway pier is introduced and studied. Deformation control measures of rectangular pipe jacking construction in the process are put forward according to the specific characteristics of the surrounding environment of the project,which has important reference and reference value for similar projects.
Research conclusions: Through the analysis of settlement monitoring results of the surface longitudinal section and transverse section and surrounding structures, the following conclusions are drawn : ( 1 ) In the longitudinal uneven distribution of ground subsidence caused by rectangular pipe jacking construction, launching section settlement is larger, settlement control in central section is better,and the part close to the receiving well presents uplift. (2) Due to the constraints of boundary conditions, the transverse subsidence range caused by rectangular pipe jacking construction is larger,obvious settlement appears within 2 times of its width range. (3) When the pipe jacking machine passed monitoring section, ground subsidence continued stable development to the end of construction in this project, the settlement rate of pipe jacking was about 0. 5 mm/d. (4) Because of its resistance to pier deformation capacity, the construction process did not have a significant impact on the pier, and the environmental impact has been well controlled. (5) The research results can provide references for the design and construction of rectangular pipe jacking for subway underpass.