Centrifugal model test device and method for influence of tunnel-foundation pit multiple excavation on existing pile foundation

Abstract

The invention relates to a centrifugal model test device for influence of tunnel-foundation pit multiple excavation on an existing pile foundation. The centrifugal model test device comprises a modelbox, a model pile, a model tunnel, a model foundation pit, model soil, heavy liquid, a pile head restraining device, a transverse support, a loading system, a control system and a measuring system, wherein the model box is divided into a main body test box and an auxiliary test box through a partition plate and a transverse support; the model pile comprises a pile body and a pile cap arranged at the top of the pile body, and located in a main influence area of the model tunnel and the model foundation pit; and the model tunnel comprises a lining and annular rubber bags arranged on the periphery of the lining in a sectioned mode, and the model foundation pit comprises a supporting structure and an open rubber bag. The centrifugal model test device for the influence of tunnel-foundation pitmultiple excavation on the existing pile foundation has the beneficial effects that the pile head restraining device adopts a telescopic vertical rod and a pile head clamp, so that lateral deformationof the pile head is effectively restrained, the restraining position of the pile head can be flexibly adjusted, and meanwhile various pile foundation types such as a high-low bearing platform and a piled raft foundation are simulated, and therefore the device has a wide application range.

Description

technical field [0001] The invention relates to the field of geotechnical centrifugal model tests, in particular to a centrifugal model test device and method in which multiple tunnel-foundation excavations affect existing pile foundations. Background technique [0002] The interaction between soil and structure has always been a complex subject in the field of geotechnical engineering research. Its complexity is mainly reflected in the fact that the rock and soil itself is a discontinuous medium composed of multiple phases, which has the characteristics of gravity dependence and stress path dependence. Therefore, the interaction between rock and soil mass and buildings (structures) is a complex nonlinear or dynamic structural mechanics problem. The excavation and unloading methods of tunnels and foundation pits are different, the factors causing soil deformation are different, and the soil deformation modes and sizes are also different, which in turn shows that the impact o...

AI Technical Summary

Problems solved by technology

Among them, the field test can reflect the real stress characteristics of the soil, but the test workload is large, the cost is expensive, and the influencing factors are complicated, which makes it difficult to analyze the internal mechanism of the test results.

Although the cost of the scaled model test is relatively low, it cannot or is difficult to reproduce the actual environmental conditions on site and cannot reflect the stress state of the prototype

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