Cracking Processes and Failure Modes of Rock-Like Specimens with a Set of Non-persistent Joints
- PDF / 3,318,252 Bytes
- 21 Pages / 547.087 x 737.008 pts Page_size
- 12 Downloads / 142 Views
(0123456789().,-volV) ( 01234567 89().,-volV)
ORIGINAL PAPER
Cracking Processes and Failure Modes of Rock-Like Specimens with a Set of Non-persistent Joints Jiaqi Guo
. Pengfei Liu . Shanxiu Huang . Yuan Qian . Guangjun Liu
Received: 20 July 2020 / Accepted: 3 September 2020 Springer Nature Switzerland AG 2020
Abstract To gain a better understanding of the cracking process and failure mode of rock mass with a set of coplanar non-persistent joints, the uniaxial compression tests were carried out for 15 cylindrical rock-like specimens with different joint inclination angles (a) and rock bridge lengths (Lr) prepared through a self-developed method. Results obtained from the laboratory experiments are as follows, (1) five types of failure modes of specimens are observed: tensile failure mode (T-mode), tensile dominated tensile/shear complex failure mode (TDM-mode), tensile/shear equally complex failure mode (TSEMmode), shear dominated tensile/shear complex failure mode (SDM-mode) and shear failure mode (S-mode); (2) The failure mode of specimen is T-mode or TDMmode at a = 15, and that of specimen is S-mode and SDM-mode at a = 60; and the transitional failure modes occur as a increases from 15 to 60 and from 60 to 75; (3) a greater Lr will strengthen the tension
J. Guo P. Liu Y. Qian School of Civil Engineering, Henan Polytechnic University, Jiaozuo 454000, China S. Huang (&) College of Chemistry and Chemical Engineering, Henan Polytechnic University, Jiaozuo 454000, China e-mail: [email protected] G. Liu CCCC-SHEC Fourth Highway Engineering Co., Ltd, Luoyang 471013, China
effect and mitigate the shear effect on the failure of specimen; in general, the representative value of failure mode increases as Lr increases from 10 to 30 mm. Numerical modeling by the discrete element method efficiently simulates the cracking process and fracturing behavior of the five types of failure modes in laboratory experiments. Keywords Cylindrical rock-like specimen Coplanar non-persistent joints Uniaxial compression Failure mode Cracking process
1 Introduction The rock mass in nature is subject to various objective conditions during the diagenesis process, and different types of joints are formed in the long-term geological process. According to the continuity degree of joints, rock mass with joints can be divided into persistent jointed rock mass and rock mass with non-persistent joints. The outcrop survey of rock mass shows that large-scale and persistent joints in natural rock mass only account for a small part of the total number of joints, and most joints are short and non-persistent joints (Jamil 1992). In addition, many rock engineering projects are constructed onto rockmass foundations or in surrounding rockmass with good quality as much as possible, so as to avoid the adverse effects
123
Geotech Geol Eng
caused by large-scale persistent joints. Therefore, based on the above two points, the joints that dominate the mechanical properties of the engineering rock mass are mostly non-persistent joints. Th
Data Loading...
