Indoor model testing device and method for influences of ground loading on existing subway tunnel

Abstract

The invention relates to an indoor model testing device and method for influences of ground loading on an existing subway tunnel. The device comprises a loading device, a main body framework structure, a drawer type tank box structure and a tunnel model, wherein the main body framework structure comprises steel boards, rectangular connecting steel tubes and horizontal slide ways, the side surfaceand bottom of the main body framework are formed by the steel boards through surrounding, the rectangular connecting steel tubes are bridged on the front and rear surfaces of the steel boards on the left and right sides, a hollow compartment is formed between the upper and lower rectangular connecting steel tubes, and the horizontal slide ways are arranged on the bottom sides of two sides of the hollow compartment; and the loading device comprises a movable counter-force beam, a movable jack and a jacking force frame, the movable counter-force beam is arranged at the top of the steel boards inparallel, and the movable jack is arranged at the bottom of the movable counter-force beam; and the jacking force frame is mounted on the surface of a soil body. The indoor model testing device has the beneficial effects that the loading device is simple in structure and convenient to operate; by utilizing a drawer type design structure, the tunnel model can be rapidly replaced; multiple workingconditions can be simulated by virtue of one model tank; and the testing operation is rapid, and the testing schedule is accelerated.

Description

technical field [0001] The invention belongs to the technical field of tunnel engineering in geotechnical and underground engineering, and particularly relates to an indoor model test device and a test method for ground surcharges affecting existing subway tunnels. Background technique [0002] With the development of urban infrastructure construction and the further development of urban underground space, rail transit has become an important part of the public transport system in many big cities, and the subway shield tunnel is the main structural form of urban rail transit, which inevitably changes getting denser. However, in the actual excavation and operation of subway tunnels, various safety accidents often occur and cause a lot of losses. Therefore, the engineering community has also carried out a lot of research on the safety of tunnel structures. Among them, the physical model test based on the similarity theory is an important means to study and analyze tunnel safe...

AI Technical Summary

Problems solved by technology

However, the current indoor reduced-scale model test cannot complete the simulation of various conditions in a short period of time.

After the tunnel model is made, it is pre-embedded in the model box, which requires a lot of manpower and time to install the measuring equipment and load and unload the test soil

This also makes a single indoor model test take a long time, resulting in the extension of the entire test cycle, which limits the promotion and application of model tests

[0004] To sum up, there are still many deficiencies in the function of the existing reduced-scale model box for simulating the impact of ground load on shield tunnel segments.

That is, the simulated working conditions are single. Once the tunnel is buried, the buried depth, pipe diameter, and the relationship between the pipelines are determined, and even the action point of the surcharge has been determined. It is impossible to make temporary adjustments and adjustments in a short period of time during the test. Variety

Secondly, the huge model box is an integrated design. The installation of measuring equipment and the loading and unloading of soil materials require a lot of manpower and time, which slows down the progress of the test.

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