Effect of hydrothermal coupling on energy evolution, damage, and microscopic characteristics of sandstone

High Temperature Materials and Processes

Rongrong Zhang¹  Dongdong Ma¹  Qinyong Ma¹  Qi Ping¹ 

[1] State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mine, Anhui University of Science and Technology, Huainan 232001, Anhui, China;

关键词: split hopkinson pressure bar;    hydrothermal coupling;    energy evolution;    heat–cool cycles;    damage;   

DOI  :  10.1515/htmp-2020-0070

来源: DOAJ

【 摘 要 】

Heat–cool (H–C) cycle is a serious natural weathering mechanism for rock engineering in temperate desert climate; meanwhile, engineering rocks usually involve responses to impact loads arising from blasting operation, mechanized construction, and seismic oscillation. Considering the universality and destructiveness of rock failure caused by H–C cycle weathering coupled with dynamic loading, split Hopkinson pressure bar tests were conducted for sandstone with various H–C cycles. Additionally, hydrothermal coupled damage (D) was defined based on variation of total import strain energy. Energy evolution, damage, and microscopic characteristics of sandstone after diffierent H–C cycles were studied. Finally, the microcosmic structure changes of sandstone after various H–C cycles are compared by means of scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) technology. Results show that decreasing rate of total import strain energy in high temperature group is significantly larger compared with that in low temperature group and moderate temperature groups. Repeated H–C cycles produce the thermal stress at the mineral boundary constantly and fracture along the boundary of the mineral particle according to the SEM and EDS results.

【 授权许可】

Unknown