TY - JOUR
T1 - Effects of the loading and unloading conditions on crack propagation in high composite slope of deep open-pit mine
AU - Chang, Zhiguo
AU - Cai, Qingxiang
AU - Zhou, Wei
AU - Jiskani, Izhar Mithal
AU - Wang, Rui
N1 - Funding Information:
-is research was funded by the National Key Research and Development Program of China (2016YFC0501100), the General Program of National Natural Science Foundation of China (51574222), and the Natural Science Foundation of Xinjiang Province of China (2018D01A42). -e authors are grateful to all the generous support.
Publisher Copyright:
© 2019 Zhiguo Chang et al.
PY - 2019
Y1 - 2019
N2 - In the process of open-pit excavation and stacking of dump along the side wall, the rock mass inside the composite slope undergoes complicated loading and unloading effect, which are manifested as triaxial stress → horizontal unloading → axial loading. In this study, a corresponding mechanical model of crack propagation in composite slope under loading and unloading effects was established. The stress-strain curves and deformation characteristics of rock under different stress paths were studied. A series of different tests under unloading pressure condition were carried out to study the behavior of the rock fracture under different confining pressure paths. The results showed that under the same initial stress conditions, the deviator stress required for rock unloading failure was less than that of the conventional triaxial compression. The axial deformation of rock samples was gradually increased with the increase of unloading, and the unloading easily led to rock failure. By analyzing the crack propagation mechanism under loading and unloading stress field, the analytic relation of the limit height of the composite slope with the crack morphology as the variation was determined when crack propagation occurred near the slope surface. This study provides a technical note on local damage and cracks propagation of a fractured rock mass under the loading-unloading effects in high composite slope.
AB - In the process of open-pit excavation and stacking of dump along the side wall, the rock mass inside the composite slope undergoes complicated loading and unloading effect, which are manifested as triaxial stress → horizontal unloading → axial loading. In this study, a corresponding mechanical model of crack propagation in composite slope under loading and unloading effects was established. The stress-strain curves and deformation characteristics of rock under different stress paths were studied. A series of different tests under unloading pressure condition were carried out to study the behavior of the rock fracture under different confining pressure paths. The results showed that under the same initial stress conditions, the deviator stress required for rock unloading failure was less than that of the conventional triaxial compression. The axial deformation of rock samples was gradually increased with the increase of unloading, and the unloading easily led to rock failure. By analyzing the crack propagation mechanism under loading and unloading stress field, the analytic relation of the limit height of the composite slope with the crack morphology as the variation was determined when crack propagation occurred near the slope surface. This study provides a technical note on local damage and cracks propagation of a fractured rock mass under the loading-unloading effects in high composite slope.
UR - http://www.scopus.com/inward/record.url?scp=85067127232&partnerID=8YFLogxK
U2 - 10.1155/2019/3168481
DO - 10.1155/2019/3168481
M3 - Journal article
AN - SCOPUS:85067127232
SN - 1687-8086
VL - 2019
JO - Advances in Civil Engineering
JF - Advances in Civil Engineering
M1 - 3168481
ER -