Comprehensive test system of shield tunnel construction model

Abstract

The invention provides a comprehensive testing system for a shield tunnel structural model, which comprises a soil horizon simulating and soil pressure loading device and a tunnel structural model; the soil horizon simulating and soil pressure loading device is a simulated soil body cavity enclosed by steel plates; a horizontal reaction frame is arranged outside the soil body cavity; a horizontal soil pressure jack is connected between each edge of the reaction frame and the soil body cavity; the tunnel structural model is attached with a uniform water pressure loading device and a non-uniform water pressure loading device, and is axially and vertically arranged in the center of the soil body cavity; simulation testing soil is filled between the tunnel structural model and the soil body cavity; the upper part of the soil body cavity is covered by a steel cover board; a vertical reaction portal frame is arranged above the soil body cavity; and a vertical soil pressure jack is connected between the lower part of a girder of the vertical reaction portal frame and the steel cover board. The system can simulate interactions between tunnel structures in different forms of fractures with the stratum under different stratigraphic and hydrologic conditions, and more truly simulate the environment conditions of the tunnel structures with more accurate and reliable test data, thereby providing more reliable safeguard for shield tunnel constructions.

Description

technical field [0001] The invention relates to a comprehensive test system for a shield tunnel structure model. Background technique [0002] In the construction process of shield tunneling, the force of the tunnel structure and the interaction with the surrounding strata are very complicated, so it is necessary to study the interaction relationship between the tunnel structure and the stratum Provide guarantee for safe and smooth construction. [0003] Existing research on the relationship between tunnel structure and soil, such as the simulation test of the shield tunnel-soil complex in the single-track subway section conducted by the Structural Laboratory of the Department of Civil Engineering, Waseda University, Japan, and the Japan Institute of Civil Engineering, this test will The ring-shaped shield tunnel model is placed vertically (the central axis of the model tunnel is parallel to the horizontal plane) in a sealed cabin, and the cabin is filled with model test so...

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Problems solved by technology

However, in this test, the test device did not and could not constrain the longitudinal (central axis) direction of the model tunnel. The model tunnel was not in a plane strain state when loaded, and could not reflect the plane strain characteristics of the tunnel.

In addition, since the model tunnel is placed vertically and the loading cabin is vertically flat, the top soil must be dug out before loading and unloading the model tunnel, which makes it inconvenient to replace the tunnel model; and the airtight cabin is expensive and limited in size, and the size of the model tunnel Restricted, only small-sized tunnel models can be tested; at the same time, it is troublesome to replace the model test soil due to the inconvenient access to the cabin; and because the pressurized water is mixed with the model test soil, the test materials can only be used once , causing waste

In addition, adding pressurized water will affect the ratio of model soil materials, making it difficult to guarantee the physical properties of soil materials, and it is difficult to accurately control the actual water pressure on the model segment

Due to the influence of underground hydrogeological conditions, some shield tunnels are greatly affected by groundwater, and the existing model test systems cannot accurately simulate the influence of water load

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