The ageing disintegration, the damage, and failure mechanism of water-saturated soft rock are of significance to hazard prevention for deep mining. In this paper, indoor experiments, including disintegration behaviour tests in water, uniaxial compression failure tests of rock samples with different water contents, and variations in the microstructure of mudstone under saturated water contents, were conducted. The investigation results show that the saturated water content of mudstone is 16.96% and that the rock mass bursts completely after being immersed in water for 72 h. With increasing water content, the uniaxial strength and elastic modulus at the prepeak stage present significant attenuation. However, Poisson’s ratio varies little, which indicates that the swelling of cemented mudstone is not obvious when meeting water. In addition, the failure pattern of mudstone changes from overall splitting failure to block fragmentation failure. Due to ion-exchange adsorption and the wedging action of water molecules, the edge of contact between particles changes from staggered to smooth, which leads to the expansion of pores, the loosening of mudstone structures, and a decrease in mechanical strength. Therefore, the diffusion, migration, and particle expansion of illite and other clay minerals in mudstone are the main factors leading to the structural damage and strength reduction of weakly cemented rock under water-rock interactions.

中文翻译：

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深部软岩水岩相互作用损伤劣化行为试验研究

饱和水软岩的老化解体、破坏及破坏机制对深部开采的灾害防治具有重要意义。本文进行了室内试验，包括水中崩解行为试验、不同含水率岩样的单轴压缩破坏试验、饱和含水率下泥岩微观结构的变化等。调查结果表明，泥岩饱和含水率为16.96%，浸水72 h后岩体完全破裂。随着含水量的增加，峰前阶段的单轴强度和弹性模量呈现显着衰减。但泊松比变化不大，说明胶结泥岩遇水膨胀不明显。此外，泥岩破坏模式由整体分裂破坏转变为块体破碎破坏。由于离子交换吸附和水分子的楔入作用，颗粒之间的接触边缘由交错变光滑，导致孔隙扩大，泥岩结构松动，机械强度下降。因此，伊利石等黏土矿物在泥岩中的扩散、运移和颗粒膨胀是导致水岩相互作用下弱胶结岩结构破坏和强度降低的主要因素。导致孔隙扩大，泥岩结构松动，机械强度下降。因此，伊利石等黏土矿物在泥岩中的扩散、运移和颗粒膨胀是导致水岩相互作用下弱胶结岩结构破坏和强度降低的主要因素。导致孔隙扩大，泥岩结构松动，机械强度下降。因此，伊利石等黏土矿物在泥岩中的扩散、运移和颗粒膨胀是导致水岩相互作用下弱胶结岩结构破坏和强度降低的主要因素。