Control Standard of Ground Surface Settlement Induced by Running Tunnel Construction in Beijing Subway

Abstract

Ground settlement, especially the ground surface settlement induced by subway tunneling is an important issue. However, there is no an agreed standard for controlling ground surface settlement during the subway construction at present. The control standard of ground surface settlement was studied using the methods of statistical analysis and numerical simulation based on the running tunnel in Beijing subway. According to the research results, a conclusion could be obtained that the ground surface settlement can be controlled within 40 mm using the general construction measures in Beijing subway running tunnel construction, and furthermore, the settlement of 40mm will not damage the existing nearby structures and utilities including neighboring buildings, bridges and pipelines, etc. So the control valve of 40 mm is rational, which can be adopted as the control standard of ground surface settlement induced by running tunnel construction in Beijing subway.

Study on the Effects of Artificial Trapezoidal Freezing Soil Mass on the Stability of Large-Diameter Shield Tunnel Portal

“…The results show that if the triaxial mixing pile's longitudinal length is 5 m, the maximum tunnel portal deformation is approximately 25 mm. The deformation value is above the allowable value of 15 mm [24,25]. To highlight the effect of the freezing soil mass, the triaxial mixing pile's longitudinal length was 5 m in this section.…”

“…The maximum y-direction displacement is −5.66 mm. The maximum displacement value is much less than the allowable value of 15 mm [24,25]. This means the optimized scheme can also meet the safety requirements of real engineering.…”