Particle arching characteristic test device and test method thereof

Abstract

The invention provides a particle arching characteristic test device and a test method thereof. The test device comprises a height-adjustable platform institution, a perspective mold case mechanism used for accommodating particle samples, a loading mechanism capable of controlling frequency conversion and a levelling support mechanism, wherein the platform mechanism is positioned below the support mechanism; the mold case mechanism is arranged on the platform mechanism; the loading mechanism is arranged on the support mechanism and comprises a loading end; the loading end penetrates through the support mechanism and used for continuously applying dynamic loading to the particle samples; the bottom of the mold case mechanism is provided with dodge gates capable of adjusting opening or folding, and a particle feeding hole is formed between the opened dodge gates so as to ensure particle feeding and arching of the particle samples. The invention researches that under the effect of dynamic load, after a particle system is subjected to arching, a theoretical guide role can be achieved for the problems such as arch effect degradation, invalid microscomic evolution process, gradual change mechanism and degradation and even unavailability of soil arching effect, and furthermore particle displacement and particle contact force changes can be synchronously obtained.

Description

technical field [0001] The invention belongs to the technical field of underground engineering tests, and relates to a test device and a test method for particle arching characteristics. Background technique [0002] As is well known in the industry, the soil arch effect widely exists in underground structures, such as pipe shed maintenance structures in underground engineering, vaulted tunnels, anti-slide piles in geotechnical engineering, pile-supported roadbeds, etc. Under the action of static load, the soil arching effect is stable for a long time, and the academic and engineering circles have basically formed a consensus on its mechanism. However, existing engineering and experimental studies have shown that the soil arching effect is not stable when subjected to dynamic forces, especially under the conditions of small overlying soil thickness, long-term dynamic load cycles or large instantaneous dynamic loads, the arching effect may degrade or fail entirely. At prese...

AI Technical Summary

Problems solved by technology

[0004] At present, there are few studies on the evolution of soil arching effect under cyclic dynamic loads, and most of them are descriptions of the evolution phenomenon and characteristics of arching effects under laboratory test conditions, and few studies involve the evolution mechanism of soil arching effects under dynamic loads. It is also difficult to consider the influence of long-term cyclic loading on the soil arching effect, so that the relevant engineering design under dynamic loading is still limited to quasi-static correction or empirical design methods based on dynamic test laws

Images