Large model test device simulating deep vertical shaft freezing

Abstract

The invention discloses a large model test device simulating deep vertical shaft freezing. The large model test device comprises a model test barrel, a slurry loading system, a hydraulic system, an excavation simulation system, a refrigerating system, a monitoring system and a data collection and control system, wherein the excavation simulation system is located in a soil sample, the soil sample is located in the model test barrel, the slurry loading system, the hydraulic system and the data collection and control system are all located outside the model test barrel, one part of the monitoring end of the monitoring system is buried into the soil sample, the other part of the monitoring end of the monitoring system is located in the excavation simulation system, the output end of the monitoring system is connected with the input end of the data collection and control system, the hydraulic system provides hydraulic driving force for the excavation simulation system, a slurry output opening of the slurry loading system is communicated with cavity fluid between the inner wall of the model test barrel and the soil sample, and the refrigerating system provides circulation low temperature liquid for soil sample freezing. By means of the large model test device simulating deep vertical shaft freezing, when a test is carried out, formation of a freezing wall in the deep vertical shaft freezing process and displacement change conditions of well side during shaft excavation can be really reflected.

Description

technical field [0001] The invention relates to a deep shaft freezing simulation device, in particular to a large-scale model test device for simulating deep shaft freezing. Background technique [0002] The freezing method is to drill holes from the ground along the concentric circle with a certain distance outside the proposed vertical shaft before the wellbore is excavated. Refrigeration equipment, using a circulating pump to input refrigerant into the freezing tube, the refrigerant continuously absorbs the heat outside the tube for a long time to freeze the surrounding stratum, so that it can withstand water and soil pressure and block groundwater, and excavation under its protection Strata and building linings. [0003] Therefore, the freezing method is mainly suitable for shaft engineering in loose and unstable alluvium, water-bearing rock formations with developed fractures, silt, soft mudstone, and formations with saturated water content and high water head; it is a...

AI Technical Summary

Problems solved by technology

However, the simulation devices in the prior art have the following technical defects: (1) The effective test space of the test device is generally insufficient, and boundary effects and scale effects often have adverse effects on test results

(2) It is difficult to take into account the structural force and the convenience of test operation. Some test benches are easy to operate but the structural force is not good, so it is difficult to achieve high pressure loading

(3) It is difficult to simulate the ground pressure loading on large rock and soil specimens, and the diaphragm is fragile, which leads to the failure of the test

(4) It is difficult to simulate the excavation of the wellbore, and it is difficult to monitor the displacement and deformation of the side of the well after excavation

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