Mechanical properties and progressive failure characteristics of sandstone containing elliptical and square openings subjected to biaxial stress
Open Access
- 4 March 2021
- journal article
- research article
- Published by Public Library of Science (PLoS) in PLOS ONE
- Vol. 16 (3), e0246815
- https://doi.org/10.1371/journal.pone.0246815
Abstract
Two kinds of common tunnel shapes, i.e. elliptical opening and square opening were selected for biaxial compression tests, and the influences of two kinds of opening shapes on the mechanical properties, failure characteristics and failure modes of sandstone were compared and analyzed. The complex variable theory and mapping functions were used to obtain the analytical stress solution around elliptical and square openings. The results show that the stability of the specimen containing an elliptical opening was better than that of the specimen containing a square opening under the same lateral stress. Compared with the elliptical opening, the local damage was formed earlier in the square opening which might be caused by a higher stress concentration around the square opening. The stress distributions around openings were influenced by the opening shape and lateral stress coefficient. The top and bottom of square opening were more prone to tensile fracture, and the distribution range of tensile was larger than that of elliptical opening. When the opening failed, the intensity of square opening failure was weaker than that of elliptical opening. On the basis of the average frequency value and the rise angle value, the failure mode of specimen containing elliptical or square opening was distinguished. It was found that the mixed tension and shear failure dominated the failure of specimens with different opening shapes, and the number of shear cracks in the specimen containing a square opening was greater than that in the specimen containing an elliptical opening. The above method of judging failure mode by acoustic emission signals was well verified by the CT images of damaged specimens.Funding Information
- Graduate Research and Innovation Foundation of Chongqing (CYB19045)
This publication has 31 references indexed in Scilit:
- Modeling hard rock failure induced by structural planes around deep circular tunnelsEngineering Fracture Mechanics, 2018
- Experimental simulation investigation on rockburst induced by spalling failure in deep circular tunnelsTunnelling and Underground Space Technology, 2018
- Mechanical behavior of an opening in a jointed rock-like specimen under uniaxial loading: Experimental studies and particle mechanics approachArchives of Civil and Mechanical Engineering, 2017
- Experimental Study of Slabbing and Rockburst Induced by True-Triaxial Unloading and Local Dynamic DisturbanceRock Mechanics and Rock Engineering, 2016
- Numerical study on static and dynamic fracture evolution around rock cavitiesJournal of Rock Mechanics and Geotechnical Engineering, 2013
- Influence of Unloading Rate on the Strainburst Characteristics of Beishan Granite Under True-Triaxial Unloading ConditionsRock Mechanics and Rock Engineering, 2013
- Dynamic response of rock mass induced by the transient release of in-situ stressInternational Journal of Rock Mechanics and Mining Sciences, 2012
- Influence of intermediate principal stress on rock fracturing and strength near excavation boundaries—Insight from numerical modelingInternational Journal of Rock Mechanics and Mining Sciences, 2008
- The effect of crack tunneling on crack growth: experiments and CTOA analysesEngineering Fracture Mechanics, 2003
- Simulation of failure around a circular opening in rockInternational Journal of Rock Mechanics and Mining Sciences, 2002