Roadways fracture response under varying dominant blasting frequencies and lateral pressure coefficients

• Published in: International journal of impact engineering Vol. 181; p. 104761
• Main Authors: Si, Yingtao, Liu, Jianpo, Li, Fengtian, Wang, Yongxin, Song, Jiancun, Zhao, Fuquan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.11.2023
• Subjects: Acoustic emission; Discrete element methods; Lateral pressure coefficient; Microcracks; Roadways; Waveform frequency; Microcracks; Waveform frequency; Lateral pressure coefficient; Acoustic emission; Discrete element methods; Roadways
• ISSN: 0734-743X; 1879-3509
• DOI: 10.1016/j.ijimpeng.2023.104761

•Microcracks inside the rock mass induced by repeated blast loading were obtained by using acoustic emission and discrete element methods.•Microcracks behaviors in response to varying blast waveform frequencies and geo-stresses are investigated.•The difference in damage-prone regions induced by static loading and blast disturbance is analyzed. Dominant frequency of blasting waveform attenuates with increasing propagation distance, leading to diverse diffractive effects on a roadway located in different sublevels. To investigate the roadway fracture characteristics in response to varying blasting wave frequencies and geo-stresses. Numerical simulation and experiments were performed by using discrete element methods and acoustic emission (AE) techniques, respectively. Roadway response differences in terms of microcracks propagation regions were primarily investigated, to reveal the relationships between damage-prone regions and the lateral pressure coefficient and blast waveform frequencies. The results showed that the excavation damage zone (EDZ) and the types of microcracks developed are primarily influenced by the principal stress direction. Low-frequencies blast waves contribute significantly to the overall damage to the surrounding rock around the roadway, while high-frequencies blast waves mainly damage the sides of the facing blast. Under the coupling effect of principal stress and blast wave, microcracks are more prone to generate in regions coupling with high-stress concentration regions induced by principal stress and disturbed regions diffracted by blast waves. With the results from this study, the roadway support should consider the difference in damage-prone regions triggered by blasting waves with varying dominant frequencies under different lateral pressure coefficients.