Study on Energy Evolution Process of Hard Brittle Rock under Uniaxial Compression

Abstract

In long term practice of rock engineering, the strength and failure rules based on classical elasticity and plasticity theory is always dominated in judging the safety and stability of practical engineering. However, stress-strain relationship is only a certain state of rock mass in loading process, and it is hard to give an accurate evaluation for the engineers especially due to the diversity and divergence of mechanical parameters. For actual loading process of rock mass is always companied with energy dissipation and releasing, in this paper, we put emphasis on the ratio of dissipated energy to overall absorbed energy in the cyclic loading process. From this point of view, three important sections are gained as follows: a) condensing section: the ratio is higher due to the closing effect of original cracks; b): elastic section: the value of ratio sharply goes down and is nearly a constant in the elastic section; c) approaching to failure section: this is a section closely to the failure because the newly cracks occurs ceaselessly and the ratio value becomes higher.