Experimental study on effect of pre-crack on creep behavior of brittle rocks

Document Type : Original Article

Authors

Rock Mechanics Group, Department of Mining Engineering, School of Engineering, Tarbiat Modares University, Tehran, Iran

Abstract

Long-term rock deformation is one of the critical problems in rock engineering design. This study presents results of some laboratory creep tests for assessment of time-dependent behavior of two rocks with different brittleness: Sandstone as a semi-brittle and Marble as a brittle rock. Brazilian disk specimens are used to plan some indirect tension creep loading tests. Also, Single Edge Crack Brazilian Disk (SECBD) is employed to evaluate the effect of pre-crack on the creep behavior of rocks. Totally, 12 creep loading tests are performed on the two rock types with three loading severity. Result of experimental tests indicates that failure time reduction percent due to existence of pre-crack in Marble specimen is more than Sandstone. In other words, the effect of pre-crack on the reduction of failure time and strain is more noticeable in more brittle rock.   

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