Experimental investigation on the energy evolution of dry and water-saturated red sandstones  

作　　者：Zhang Zhizhen Gao Feng 

机构地区：[1]State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology [2]School of Mechanics and Civil Engineering,China University of Mining and Technology

出　　处：《International Journal of Mining Science and Technology》2015年第3期383-388,共6页矿业科学技术学报（英文版）

基　　金：provided by the Fundamental Research Funds for the Central Universities(No.2014QNA80);the Project funded by China Postdoctoral Science Foundation(No.2014M550315);a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions;the National Natural Science Foundation of China(No.11202108);the Natural Science Foundation of Jiangsu Province(No.BK20140189)

摘　　要：In order to investigate the effect of water content on the energy evolution of red sandstone, the axial loading–unloading experiments on dry and water-saturated sandstone samples were conducted, and the distribution and evolution of elastic energy and dissipated energy within the rock were measured.The results show that the saturation process from dry to fully-saturated states reduces the strength, rigidity and brittleness of the rock by 30.2%, 25.5% and 16.7%, respectively. The water-saturated sample has larger irreversible deformation in the pre-peak stage and smaller stress drop in the post-peak stage.The saturation process decreases the accumulation energy limit by 38.9%, but increases the dissipated energy and residual elastic energy density, thus greatly reducing the magnitude and rate of energy release. The water-saturated sample has lower conversion efficiency to elastic energy by 3% in the prepeak region; moreover, the elastic energy ratio falls with a smaller range in the post-peak stage.Therefore, saturation process can greatly reduce the risk of dynamic disaster, and heterogeneous water content can lead to dynamic disaster possibly on the other hand.In order to investigate the effect of water content on the energy evolution of red sandstone, the axial loading–unloading experiments on dry and water-saturated sandstone samples were conducted, and the distribution and evolution of elastic energy and dissipated energy within the rock were measured. The results show that the saturation process from dry to fully-saturated states reduces the strength, rigid-ity and brittleness of the rock by 30.2%, 25.5%and 16.7%, respectively. The water-saturated sample has larger irreversible deformation in the pre-peak stage and smaller stress drop in the post-peak stage. The saturation process decreases the accumulation energy limit by 38.9%, but increases the dissipated energy and residual elastic energy density, thus greatly reducing the magnitude and rate of energy release. The water-saturated sample has lower conversion efficiency to elastic energy by 3%in the pre-peak region; moreover, the elastic energy ratio falls with a smaller range in the post-peak stage. Therefore, saturation process can greatly reduce the risk of dynamic disaster, and heterogeneous water content can lead to dynamic disaster possibly on the other hand.

关 键 词：Rock mechanics Energy evolution Energy distribution Triaxial compression Saturation process 

分 类 号：TU45[建筑科学—岩土工程]