Rock creep rupture measuring method after peak strength

Abstract

The invention belongs to the field of rock engineering, and specifically relates to a rock creep rupture measuring method after the peak strength. The measuring method comprises the following steps (1) manufacturing a rock sample; (2) installing a strain sensor; (3) applying an initial confining pressure; (4) applying an axial pressure until the axial pressure is near to the peak strength; (5) unloading the confining pressure so as to generate primary ruptures on the rock sample; (6) applying a secondary stronger confining pressure; (7) applying a secondary axial pressure; (8) maintain a constant axial pressure, and observing the secondary ruptures. The method can actually imitate the mechanics characteristics of an engineering rock, which is in a high stress region, is ruptured after digging, then is solidified by supports, continues to bear the stress after the solidification, and suffers a long-term deformation; the operation method is simple and convenient, and the method can be applied to researches of mechanical behavior after the peak strength of rocks in high stress areas in the fields of water power, traffic, energy, mines, and the like.

Description

technical field [0001] The invention belongs to the field of geotechnical engineering, and in particular relates to a test method for creep cracking after a rock peak. Background technique [0002] With the implementation of related strategies such as the development of the west, rock engineering has been continuously constructed, and the excavation scale of underground space has become larger and larger, and the buried depth is also increasing. For example, the four diversion tunnels of the Jinping II Hydropower Station have a maximum buried depth of 2525m, making them the largest hydraulic diversion tunnels in the world in both depth and scale. Mineral resources and oil extraction also extend to the deep, and the mining depth of many mines has reached more than 1200m. The high ground stress accompanied by high buried depth often increases the risk of rockburst, and the roadway (tunnel) deformation lasts for a long time. The distinctive feature of deep rock engineering th...

AI Technical Summary

Problems solved by technology

It does not take into account that the support and reinforcement measures in actual engineering are equivalent to the increase of confining pressure

[0006] 2. The article "Experimental Research and Countermeasure Analysis of Rock Post-Peak Mechanical Behavior Considering the Effect of Confining Pressure" conducts research on the post-peak mechanical behavior of rock considering the effect of confining pressure (see "Wuhan Survey and Design" Issue 3, 2013, author: Yin Juntao, et al. ), this method effectively analyzes the law of rock post-peak strength changing with confining pressure, without considering the long-term creep and re-rupture problem

[0007] 3. The article "Uniaxial Test Study on Mechanical Properties of Rocks Before and After Post-Peak Grouting Reinforcement" introduces a method for studying the uniaxial mechanical properties of rocks after post-peak grouting reinforcement (see "Journal of Underground Space and Engineering", No. 1, 2007 , author: Wang Hanpeng, etc.), this method effectively solves the effect of rock reinforcement after the peak, but cannot reflect the long-term creep effect

[0008] 4. The article "Experimental Research on Rock Creep Fracture Process and Its Response Ratio Change" introduces the experimental research on the rock creep rupture process and its response ratio change (see "Acta Seismological Sciences" 2010 No. 3, author: Shi Xingjue, etc.), this method studies the primary fracture of the rock under the action of creep, and does not involve the creep refracture of the deformation stage after the rock fracture peak

Images