Subway Tunnel Shield Construction Surface Subsidence Mechanism And Control Measures

This paper, taking xi ’an subway line one TJSG- 9 standard as the background, in view of the xi ’an special collapsible loess strata subsidence control difficulty, project along the pipeline, built-up, interval through the national key protected cultural relics- xi ’an ancient city wall and moat important buildings, such as the settlement control requirements are very high unfavorable factors.Focuses on earth pressure balance shield machine in xi ’an typical construction of collapsible loess stratum, the tunnel buried depth, formation conditions, the excavation parameters of shield machine, construction measures on the occurrence of land subsidence, the influence of the law of development, as well as corresponding measures after the change rule of ground subsidence. Theoretical calculation and numerical analysis is adopted to establish the model of the moat old bridge and the settlement of xi ’an ancient city wall to make prediction and analysis, and through the actual construction process parameter setting and value in the acquisition, finally summarizes the subsidence regularity and construction experience, for the similar strata subsidence mechanism and control measures to provide reference and reference.