Test method for simulating erosion loss of sandy soil layer surrounding shield tunnel segment seam

Abstract

The invention relates to a test method for simulating the erosion loss of a sandy soil layer surrounding a shield tunnel segment seam. An apparatus used in the invention comprises an air pump, a main test system, a pressure water tank system and a data acquisition system, and the main test system comprises a main test box with the bottom being opened; the upper portion of the main test box is provided with a sealing top cover, and the top cover is connected with a detachable pressurization airbag and is fixedly provided with a precise pressure regulating valve and a digital display pressure gauge; the lower portion of the main test box is provided with a miniature vibrating wire piezometer and a miniature earth pressure gauge; and the bottom of the main test box is in sealing connection with two L-shaped adjustable baseboards through an elastic sealing gasket and an L-shaped baseboard elastic sealing gasket which are arranged at the lower portion of the main test portion, the two L-shaped adjustable baseboards are connected through screws, and the two L-shaped adjustable baseboards are provided with grooves used for fixing the L-shaped baseboard elastic sealing gasket. The screws are adjusted in the test process to make the seam width be consistent with the open amount of a shield tunnel segment. The method can be used to assess the erosion condition of different types of soil surrounding the seam.

Description

technical field [0001] The invention relates to a test method for simulating the erosion and loss of the sand layer around the joints of the shield tunnel segment, which is mainly suitable for evaluating and predicting the erosion and loss of the soil around the segment of the shield tunnel. Background technique [0002] Shield tunnels are generally assembled from many impermeable concrete segments. Due to the uneven settlement of the tunnel, local leakage is prone to occur during the construction and operation of the tunnel, and the leakage is easy to carry fine particles in the soil. out, forming erosion. Local erosion will cause the shield segment to lose its soil support, and if it is not handled properly, it will cause disasters, causing huge environmental impact and economic losses. Monitoring and evaluating the erosion and loss of soil around the joints of shield tunnels can not only reflect the degree of disease of shield segments, but also predict the development o...

AI Technical Summary

Problems solved by technology

[0003] The traditional test method is limited to testing the waterproof performance of the segment elastic gasket, as described in "Polymer Waterproof Materials Part 4: Rubber Gasket for Shield Tunnel Segment" (GB 18173.4-2010) The test methods carried out by the water pressure test device that simulates the "T" type and "I" type assembled joints of the segments do not take the soil into consideration, but simply conduct the watertightness test of the elastic gasket

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