Experiments on Material Proportions for Similar Materials with High Similarity Ratio and Low Strength in Multilayer Shale Deposits

Yaobin Shi,Nanyan Hu,Yicheng Ye,Xianhua Wang,Xu Huang

doi:10.3390/app11209620

Yaobin Shi, Nanyan Hu + Show 3 more

Open Access

https://doi.org/10.3390/app11209620

Copy DOI

Abstract

It is important to systematically investigate the similar materials with high similarity ratio and low strength in multilayer shale deposits, to provide a scientific basis and experimental basis for the research of underground mining of multilayer shale deposits. In this paper, using an orthogonal experimental method, the physical and mechanical parameters of different material proportions were analyzed with four control factors of mica powder/standard sand, filling material/bonding material, Portland cement/gypsum, silicone oil ratio. Twenty-five groups of material proportioning schemes were designed, and the density, porosity, compressive strength, and elastic modulus of each group of materials were measured. Through the range analysis and significance analysis, the influence of control factors on the material parameters was explored, and multivariate linear regression analysis of test results was carried to eliminate outliers. The result showed that the physical and mechanical parameters of similar materials prepared according to the proportioning scheme were widely distributed, which can meet the preparation requirements of similar materials with different lithologies. The density and compressive strength were most affected by the ratio of Portland cement/gypsum, the porosity was most affected by the ratio of filling material/bonding material, and the elastic modulus was mainly controlled by the silicone oil ratio. The proportioning scheme was applied to three similar prepared shale materials with large lithology differences. The error between actual similar constant and design similar constant of low strength similar material was less than 1.62%. The physical and mechanical parameters of similar materials were in good agreement with the original rock.

Highlights

In combination with with the needs of a later physical similarity simulation test, atest, mineral material density instrument was used to test the density, a porosity instrument was used to material density instrument was used to test the density, a porosity instrument was used test the porosity, and a rock uniaxial instrument was used to test the parameters such as to test the porosity, and a rock uniaxial instrument was used to test the parameters such compressive strength and Poisson’s ratio
Since the primary motivation for this study was a similar material with high similarity ratio and low strength, we focused our discussion principally on the mechanisms controlling the compressive behavior of this rock-type
The results of the similar material proportioning test showed that the physical and mechanical properties required by the prototype of the similar model were within its distribution range

Summary

Introduction

The physical similarity simulation test is an important, effective, and scientific research method to solve complex geotechnical engineering problems [1,2,3]. Similar material simulating geotechnical mechanical properties must have the basic characteristics of high gravity, low strength, low deformation modulus, and variable internal friction angle. Materials that meet these requirements do not exist in nature and must be combined manually [6,7]. Selection and proportioning of similar materials play a decisive role in the physical similarity simulation test [8,9]

Methods

Results

Discussion

Conclusion