Support Parameters Optimization and Test for Yichang-Xingshan High Speed Railway Tunnel Based on Total Safety Factor Method
The application of Total Safety Factor Method for tunnel support structure design can realize the transformation of tunnel support structure design from analogical design to quantitative design.Relying on the optimization test section of Yichang-Xingshan high speed railway,tunnel support parameters were optimized based on Total Safety Factor Method.The safety and economy were verified by comparing design values with measured values.The main conclusions are as follows:compared with original design,the economic indexes of optimized tunnel support structure are saved by 5.24%,23.85%and 22.61%respectively under the conditions of class Ⅲ,Ⅳ and Ⅴsurrounding rock,meanwhile,the construction progress indexes are improved by 29.6%and 40.0%respectively under the conditions of class Ⅲ and Ⅳ surrounding rock.Through field test,the design value of surrounding rock pressure is greater than measured value,and the design safety factor of spray shotcrete layer is less than measured value.The optimized support parameters based on Total Safety Factor Method can meet the safety requirements,which proves that Total Safety Factor Method is reliable.
Total Safety Factor Methodoptimization of support parameterssafety factorfield testsurrounding rock pressureeconomic indexconstruction progress index