Calculation method of permeability coefficient of shield tunnel lining structure

Abstract

Disclosed is a calculation method of permeability coefficient of a shield tunnel lining structure. The calculation method includes the steps of 1), determining geometrical features of a tunnel; 2), determining the permeability coefficient ks of surrounding strata of the tunnel; 2), determining leaking water amount of the tunnel, wherein underground water is leaked into the tunnel through a tunnel connector and is collected through a water-collecting well, and the leaking water amount V1 of the groundwater collected through the water-collecting well is measured; 3), determining exterior surface are S and water collecting time t of the tunnel in water-collecting sections of the tunnel; 4), calculating leakage Ql of the tunnel per unit area per unit time; 5), calculating height of water head HR of the interface of the tunnel and the strata; 6), calculating the average permeability coefficient kl of the tunnel. On the basis of the basic features of leakage water of the shield tunnel, the average permeability coefficient determination method capable of considering the permeability features of the shield tunnel connector is established, and force and deformation effects of tunnel leakage on surrounding environment and the shield tunnel can be analyzed more accurately according to the average shield tunnel permeability coefficient acquired in calculation.

Description

technical field [0001] The invention relates to the field of tunnel structure parameter calculation, in particular to a method for determining the average permeability coefficient of a shield tunnel lining structure. Background technique [0002] Shield tunnels are assembled from segments, and the joints between segments are called joints. Water seepage is one of the main problems of operating tunnels, and joints are the main part of shield tunnel water seepage, and the water seepage of concrete segments is less than that of joints. However, in the practice of design and construction, in order not to make the calculation too complicated, the tunnel lining is usually simplified as a mean ring, and the permeability coefficient of the lining is considered to be equal, which is called the average permeability coefficient of the lining. Therefore, it is of great significance to accurately determine the average permeability coefficient of tunnel lining to obtain correct calculati...

AI Technical Summary

Problems solved by technology

This method can determine a numerical solution that is not much different from the real value of the average permeability coefficient of the lining, but the process is complicated, and empirical support is needed to estimate the range of the permeability coefficient, and it is not easy to find the optimal solution

[0009] The existing calculation methods mainly have the following two problems: 1. Relying on empirical support, it is necessary to roughly judge the range of the average permeability coefficient of the lining before calculation, and there is a certain error between the calculation results and the actual situation

2. It is highly subjective, and the parameters need to be given artificially, and the parameters will change with the difference between the structure of the joint and the hydrogeological conditions of the stratum around the tunnel, which is not conducive to software calculation and cannot be used for commercial software development

The average permeability coefficient of the lining obtained by these two methods has a certain error from its true value, which will have a certain impact on the calculation of the internal force and deformation of the tunnel in the design stage, as well as the durability and settlement of the tunnel in the operation stage.

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