Fracture toughness analysis on cracked ring disks of anisotropic rock

Fracture Propagation in Brazilian Discs with Multiple Pre-existing Notches by Using a Phase Field Method

“…Under loading, cracks initiate, propagate, and coalesce with other cracks, thereby decreasing the strength of rocks. The initiation and propagation of multiple cracks significantly affect many rock engineering problems, such as rock cutting, hydraulic fracturing, and explosive fracturing [1]. In the past decades, crack propagation in rocks has received attentions from many researches [2][3][4][5], among which many novel tests were applied to investigate crack patterns under compressive loads, such as the notched semi-circular bending tests (NSCB) [6], the cracked chevron notched semi-circular bending method (CCNSCB) [7], and the Brazil splitting tests [8].…”

Numerical Investigation of Dynamic Rock Fracture Toughness Determination Using a Semi-Circular Bend Specimen in Split Hopkinson Pressure Bar Testing

“…As an inherent attribute representing the capability of rocks to resist fracturing under dynamic circumstances, rock dynamic fracture toughness has acquired extensive applications as diverse as rock classification, structure design, seismic events, rock bursts control and prevention, explosive storage, etc. (Chen et al 2008). In these cases, rocks often damage under a rather high loading rate, and, thus, the dynamic characteristics of rocks differ significantly from their static counterparts.…”

Three-dimensional numerical evaluation of the progressive fracture mechanism of cracked chevron notched semi-circular bend rock specimens

“…Myriads of methods with varying sample configurations have been adopted in rock fracture toughness measurements including Brazilian disc (BD) method [1], notched semi-circular bend (NSCB) method [2] and [3], cracked chevron notched semi-circular bend (CCNSCB) method [4][5][6], cracked straight through Brazilian disc (CSTBD) method [7][8][9][10][11], cracked chevron notched Brazilian disc (CCNBD) method [12][13][14][15][16], diametric compression (DC) test [17], double edge cracked Brazilian disc (DECBD) method [18], edge crack triangular test [19], flattened Brazilian disc (FBD) method [20], hollow center cracked disc (HCCD) method [21], holed-cracked flattened Brazilian disc (HCFBD) method [22], holed-flattened Brazilian disc (HFBD) method [23], modified ring (MR) test [24], radial cracked ring [25] and [26], straight edge cracked round bar bend (SECRBB) http angle of friction method [27] and straight notched disk bending (SNDB) method [28]. At present, there are no standard methods of measuring Mode-I fracture toughness of rocks; only four suggested methods are proposed by International Society of Rock Mechanics (ISRM), namely chevron bending (CB) method and short rod (SR) method [29], CCNBD method [13] and NSCB method [30] and [31].…”