A sleeve-type multi-stage sand rain device and sand sample preparation method

Abstract

The invention provides a sleeve-type multi-stage sand rain device, comprising a bracket, and a first-stage sieve drum, a second-stage sieve drum and a third-stage sieve drum which are sequentially arranged on the bracket from top to bottom. The cylinder includes a first steel cylinder and a first screen. The first steel cylinder is fixed above the first screen. The outer ring of the first screen is provided with a number of arc-shaped chutes. On the threaded support rod, a screen baffle and an annular load-bearing seat ring are arranged below the first screen, and the upper and lower surfaces of the screen baffle are respectively close to the lower surface of the first screen and the upper surface of the load-bearing seat. The screen drum includes a second steel drum and a second screen, the second steel drum is fixed above the second screen, the third-stage screen drum includes a third steel drum and a third screen, and the third steel drum is fixed on the third screen online. The beneficial effects of the present invention are as follows: by adopting fully distributed rain sand, the influence of the moving path and the moving speed on the sand sample is avoided, and the overall uniformity of the sand sample and the repeatability of the test are enhanced.

Description

technical field [0001] The invention relates to the technical field of sand sample preparation, in particular to a sleeve-type multi-stage sand rain device and a sand sample preparation method. Background technique [0002] Model test is an important way to analyze geotechnical engineering problems, among which, the preparation of model base samples is a prerequisite for carrying out model tests. Taking the foundation preparation of sand samples as an example, the traditional methods mostly use heavy hammer ramming or direct dumping. Although these methods are convenient and quick, they have relatively large subjective influence factors and cannot guarantee the uniformity and repeatability of sand samples, thus affecting the subsequent tests. Analysis of results. The sand rain method is one of the commonly used sample preparation methods in the field of geotechnical engineering for the preparation of cohesionless soil. Its basic principle is to use the conversion of gravita...

AI Technical Summary

Problems solved by technology

However, the above-mentioned device inevitably introduces the influence of moving speed and path, and the moving speed is not easy to control, making it difficult to guarantee the overall uniformity and repeatability of the sand sample;

[0005] 2) Existing static devices such as: sand rain device for geotechnical engineering model test (CN201310151463), a sand rain device for preparing geotechnical centrifugal model test and its preparation method (CN201710103081). The sand mouth cannot guarantee sufficient impact and collision between sand particles, and the sand sample distribution uniformity is not enough;

[0006] 3) The existing static device controls the flow rate of the sand outlet too roughly, resulting in the inability to well control the falling energy of the sand sample, and it is difficult to realize the preparation of sand samples with different densities

Images