Method for determining minimum burial depth of complex stratum shield tunnel

Abstract

The invention relates to the technical field of tunnel construction and discloses a method for determining a minimum burial depth of a complex stratum shield tunnel. The method includes construction steps: determining a bearable maximum shear force of the shield tunnel according to a joint structure of the shield tunnel; according to a relation between the maximum shear force and a synchronous grouting pressure, determining a reasonable grouting pressure standard as a tunnel grouting control pressure; calculating according to the synchronous grouting pressure to obtain a tunnel dynamic buoyancy force, wherein the sum of the dynamic buoyancy force and a static buoyancy force is an extreme buoyancy force in a tunnel construction process; according to a shear destructive force of overlaying soil, determining a stratum limit buoyancy force which limits tunnel uplifting, wherein the sum of the limit buoyancy force and the dead weight of the tunnel is an anti-buoyancy force of the tunnel structure; comparing the extreme buoyancy force with the anti-buoyancy force to obtain the thickness of the overlaying soil, namely the minimum burial depth of the tunnel. The method is suitable for complex strata and non-silt strata such as clay and weathered strata, high flexibility in tunnel wiring is achieved, tunnel length is further reduced, and accordingly engineering cost is saved.

Description

technical field [0001] The invention relates to the technical field of tunnel construction, in particular to a method for determining the minimum buried depth of a shield tunnel in a complex stratum. Background technique [0002] With the development of my country's economy and society, more and more tunnels are used as important means of transportation construction, and the shield tunnel with the highest degree of mechanization in the tunnel has also been vigorously developed. In recent years, the shield tunnels built (under construction) in my country The total mileage has reached thousands of kilometers. For shield tunnels, the determination of the minimum buried depth is the core issue of tunnel design, which is directly related to the realization of engineering traffic functions, construction cost savings and construction safety. At present, the method commonly used in China is based on the principle of mud splitting, that is, the minimum buried depth is obtained by bac...

AI Technical Summary

Problems solved by technology

This method has good applicability in soft strata such as silt or silty soil, but it is not suitable for non-silt strata and composite strata such as clay and weathered rock strata, and a suitable method for determining the minimum buried depth of such strata is urgently needed , in order to make the wiring of the tunnel more superior, the cost more economical and the construction safer

Images