Excavation transient unloading dynam-relaxing simulation system of jointed rock under different confining pressure

Abstract

The present invention discloses an excavation transient unloading dynam-relaxing simulation system of jointed rocks under different confining pressures. The system comprises a counter-force pier, a hydraulic pressure station, a loading system, a loading device support platform, a lever, a lever support, a transition block, a transition block cushion box, an experiment table with a round groove, a circular steel tube with one end being closed, an air compressor, a 120-degree arc-shaped concrete column provided with displacement scale marks, arc-shaped air sacs, a jointed rock model and a monitoring system, wherein the arc-shaped concrete column and the arc-shaped air sacs are used for applying a confining pressure to a joint rock body, the loading system is used for applying a horizontal pressure to the jointed rock body, an inner diameter of the arc-shaped concrete column is provided with the displacement scale marks, the arc-shaped concrete column is placed inside the circular steel tube and is used for placing the jointed rock model, and the monitoring system is used for monitoring a simulation process. With adoption of the system provided by the present invention, rapid unloading of the jointed rock module under different confining pressures can be realized, and the jointed rock model can generate large vibrations and a large strain rate, which accords with unloading conditions in practical engineering.

Description

technical field [0001] The invention belongs to the field of geotechnical engineering model experiment devices, and in particular relates to a transient unloading and loosening simulation system for jointed rock mass excavation under different confining pressures. Background technique [0002] Under the long-term geological tectonic movement and human disturbance, various intricate joints with different directions will be formed in the natural rock mass. However, during the blasting and excavation of deep underground engineering, the transient unloading and stress redistribution of the surrounding rock mass are caused by the excavation disturbance, especially when blasting and excavating in the rock mass containing joints, the jointed rock mass usually appears loosening effect. Blasting excavation will remove all or part of the initial stress on the excavation surface, thereby changing the geometry of the original jointed rock mass, resulting in changes in its boundary cond...

AI Technical Summary

Problems solved by technology

Blasting excavation will remove all or part of the initial stress on the excavation surface, thereby changing the geometry of the original jointed rock mass, resulting in changes in its boundary conditions and load conditions, which may cause serious stability or deformation of the jointed rock mass control puzzle

[0003] However, in the past, the problems related to the transient unloading and loosening of jointed rock mass excavation were studied through theoretical analysis and numerical simulation methods, and the strain during the transient unloading and loosening process of jointed rock mass excavation could not be intuitively understood. , displacement and vibration

However, the existing test system for simulating excavation and unloading has a slow unloading rate, and cannot quickly unload the load on the jointed rock mass model, so the strain rate of the jointed rock mass during unloading is low. Does not conform to the actual unloading situation in the project

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