Apparatus for collecting and screening frozen soil fragments in Hopkinson test

Abstract

The invention relates to an apparatus for collecting and screening frozen soil fragments in a Hopkinson test. The apparatus comprises a protective cover which comprises an external layer semicircular protective cover and an internal layer semicircular protective cover by low temperature strong glue bonding; the protective cover is connected to a bracing frame and an internal layer slide plate by a loose-leaf hinge and a positioning pin; air vents are arranged at the lower part of the bracing frame, a channel section is arranged on the bracing frame, and a katathermometer is internally arranged in the bracing frame; a temperature control test box and a protective cover are respectively provided with a pole hole and a rotating wheel hole for a Hopkinson pressure bar and a soil scraping rotating wheel to pass through; the channel, a screw and a support bar are used for connecting the bracing frame and an electric vibrating screen; a control power supply is arranged outside a test box with controllable temperature; a temperature control system is used for controlling the temperature of the test box with controllable temperature. The apparatus can prevent secondary fragmentation of frozen soil fragments, and more frozen soil fragments are collected as possible. The frozen soil fragments are screened and treated at first time after the test, and accuracy of test data is improved.

Description

technical field [0001] The patent of the present invention relates to a device for collecting and screening frozen soil fragments in the Hopkinson experiment. Background technique [0002] Frozen soil is a heterogeneous material composed of four basic components: soil particles, ice, liquid water and gas. Due to the existence of ice inside the frozen soil, the frozen soil shows strong temperature sensitivity. The dynamic performance of frozen soil is an important part of frozen soil mechanics. It mainly studies the deformation and strength characteristics of frozen soil and the stability of soil under dynamic load. The Hopkinson compression bar test technique is an experimental method for studying the dynamic properties of materials under medium and high strain rate conditions. It has the advantages of convenient operation, simple structure, and easy control of loading waveforms. Many domestic and foreign scholars have applied it to frozen soil materials. Research. Frozen ...

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Problems solved by technology

[0003] In the above two kinds of debris collection and protection devices, because the objects considered are only brittle materials with high strength, such as rocks, concrete, etc., they do not deal with the damage characteristics of frozen soil materials after being subjected to impact loads. For example, when the frozen soil fragments collide with the protective cover when they splash, it will cause the frozen soil to be broken again; Cover; debris collection process due to environmental temperature changes lead to debris deformation and other issues

And it only simply collects the fragments after impact, and in the subsequent experimental analysis, it is usually necessary to sieve the collected fragments by particle size, if the frozen soil fragments cannot be sieved in the first time , the subsequent screening steps will inevitably cause data errors due to human factors

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