Time Effect of Chloride Erosion on Physical and Mechanical Properties of High‐Water‐Content Materials

Abstract

In order to study the characteristics of high water-content materials (HWC) undergoing chloride erosion, we analyzed and summarized changes in strength, elastic modulus, and mass of HWC materials during chloride erosion using specific experimental research, and we also described the compression failure morphologies of HWC materials after erosion. e cuboid specimens developed a horizontal crack between the top and bottom, and the cylindrical specimens developed irregular encryption cracks at the top during increasing pressure. e erosion of HWC materials exposed to calcium chloride (CaCl 2 ) solutions was relatively serious, and the erosion of the cuboid specimens was lower than that of the cylindrical specimens. e strength of HWC materials increased during prolonged erosion, and the strength of the cylindrical specimens in water was the highest, followed by the CaCl 2 and sodium chloride (NaCl) solutions. However, the strength change of the cuboid specimens after 28 d was contrary to the above order. In late erosion stages, the HWC materials had better compactness and experienced smaller compressive deformation in water than the other two solutions. In the NaCl solution, the high-water filling material had more pores and a larger deformation than the other solutions.

Stability analysis and control technology of gob-side entry retaining with double roadways by filling with high-water material in gently inclined coal seam

“…However, because of the shortcomings of traditional roadside supports, such as resistance and shrinkage and their inability to adapt to the large deformation of the surrounding rock and to effectively isolate the goaf, their use has been gradually eliminated. New high-water materials offer several advantages (Batugin et al 2021;Chang et al 2021;Orsborn and Zantos 1988;Tomlinson and Caroline 1990;Quesada-Kimzey et al 2016;Li and Liu 2018;Park et al 2019;Wang et al 2021;Wu et al 2020;Zhou et al 2020): They exhibit obvious plastic characteristics, undergo quick solidification, provide a rapid increase in resistance, have high strength, offer quick support of the roof, produce a specific compression rate after curing, are low cost, and are adaptable to the large deformation of surrounding rock of GER. Therefore, studying the engineering application of high-water material in GER roadside filling is essential for safe mining, improving coal recovery rate, and increasing economic benefits.…”

Stability Analysis and Control Technology of Gob-Side Entry Retaining with Double Roadways by Filling with High-Water Material in Gently inclined Coal Seam

“…However, due to the shortcomings of traditional roadside supports such as resistance and shrinkage cannot adapt to the large deformation of surrounding rock, supports cannot effectively isolate the goaf and difficult to achieve high mechanization, it has been gradually eliminated. The new high-water material has several characteristics (Li and Liu 2018;Wu et al 2020;Zhou et al 2020) such as obvious plastic characteristic, quick solidification, fast increase of the resistance, high strength, a certain compression rate after curing, low cost and well adapt to the large deformation of surrounding rock of GER. In recent years, it has been gradually applied in roadside filling of GER in China.…”