XU Hao-chun, JIN Ai-bing, ZHAO Yi-qing, et al. Numerical study on Brazilian splitting of heat-treated sandstone
under different contact angles[J]. 2022, 43(S2): 588-597.
XU Hao-chun, JIN Ai-bing, ZHAO Yi-qing, et al. Numerical study on Brazilian splitting of heat-treated sandstone
under different contact angles[J]. 2022, 43(S2): 588-597.DOI: 10.16285/j.rsm.2021.1778.
the Brazilian splitting of sandstone treated at 25−1 000℃ under different contact angles (2= 6º−30º) was carried out to study the stress distribution and fracture mode
and the Brazilian splitting was compared withthe direct tensile test. The results show that: 1) The surface contact loadingcan reduce the end effect in Brazilian splitting.During the loading process
tensile cracks appear in the middle of the discfirstly. With the increase of the load
the tensile cracks converge and connectat the central part of the disc
and then extend to the end of the disc. 2) Thetensile strength measured by Brazilian splittingat point contact of flat plate is less than that of direct tensile strength.The correction coefficient of the tensile strength calculation formuladecreases linearly with the increase of temperature
satisfying = −3.303×10+1.468. With the increase ofthe contact angle
the tensile strength of the Brazilian disc increases afterheat treatment of different temperatures. 3) When 2≥18º
the Brazilian disc can guarantee to have a central crack initiation. When 2= 18º−24º
the fracture mode of the disk keeps unchanged at different temperatures. The disk willdevelop an inclined crack at a lower temperature (≤600 ℃) when the contact angle is too large (2= 30º). 4) Combined with the correction coefficient and the fracture modeanalysis
the contact angle is recommended to be 18º−24º and the correction coefficient is between 0.802 6 and 0.856 0. It canensure the center crack initiation and the stability of the fracture mode atdifferent temperatures.