Device and method for testing slurry shield excavation surface mud film formation and mud film air tightness under high pressure

Abstract

The invention discloses a device and a method for testing slurry shield excavation surface mud film formation and mud film air tightness under a high pressure. The device comprises an air pressure source, a mud permeation chamber arranged in a constant temperature cabinet, a back pressure device and a water collection device, wherein the mud permeation chamber has a steel model tube structure and is fixed on a base by a bolt; a groove is formed in the base; a porous copper plate, a steel screen mesh and a piece of geotechnical cloth are sequentially laid in the groove from bottom to top; a drain valve is arranged on the side face of the base; a barrel top cover is connected with a peripheral wall by a bolt, and an air inlet and a grouting hole are formed in the barrel top cover; the mud permeation chamber is connected with an output end of the air pressure source by an air inlet pipe passing through the air inlet hole; the water collection device is a double-layer glass pipe, the bottom of the water collection device is provided with a drain valve and is connected with the drain valve arranged on the side face of the base by a drain pipe, and the top of the water collection device is connected with another output end of the air pressure source by the back pressure device. The method provided by the invention is simple and feasible; the device is capable of simulating a penetration process of mud of a slurry shield excavation surface in the stratum by means of a laboratory test so as to test the quality of a mud film; the device can bear the maximum pressure of 2.5MPa.

Description

Technical field: [0001] The invention relates to a mud film forming and mud film air tightness testing tester and a method thereof on the excavation surface of mud-water shield excavation under high pressure, belonging to the field of underground engineering. Background technique: [0002] With the development of underground space in my country, mud-water shield technology, oil drilling technology and bored pile technology have been widely used. One of the common characteristics of these technologies is that a layer of dense mud is required on the surface of the mud formation. Membrane to support the excavation surface to ensure the smooth and safe implementation of the project. As the depth of underground space development continues to increase, the requirements for the quality of mud film formation are also getting higher and higher. Due to the large buried depth of the project and complex geological conditions, it is not only uneconomical to test the film formation quality...

AI Technical Summary

Problems solved by technology

The maximum pressure environment that can be simulated by the existing test device is about 0.7MPa, which can no longer meet the needs of actual engineering

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