Results 21 to 30 of about 31,902 (254)

Deformation and damage properties of rock-like materials subjected to multi-level loading-unloading cycles

Journal of Rock Mechanics and Geotechnical Engineering, 2023
In the process of engineering construction such as tunnels and slopes, rock mass is frequently subjected to multiple levels of loading and unloading, while previous research ignores the impact of unloading rate on the stability of rock mass.
Zhizhen Liu, Ping Cao, Qingxiong Zhao, Rihong Cao, Fei Wang   +4 more
doaj   +1 more source

Experiment and particle flow simulation of unloading induced shearing properties for jointed sandstone materials

Case Studies in Construction Materials, 2023
Shear tests on sandstone containing non-connected joints under the unloading normal stress but fixed shear stress conditions were conducted with various initial normal stress and unloading rate.
Qian Yin, Saisai Wu, Jiangyu Wu, Hongwen Jing, Qiang Zhang, Yuanchao Zhang   +5 more
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Study on the evolutionary characteristics of coal burst proneness under the action of multiple mining disturbances

Energy Science & Engineering, 2023
Coal burst is a serious hazard in deep coal mining. To investigate the coal burst proneness evolution during multiple mining disturbances (MMD), this paper implemented a range of uniaxial cyclic loading–unloading tests coupled with acoustic emission (AE)
Yang Liu, Zhenhua Ouyang, Haiyang Yi, Hongyan Qin, Gen Li, Fengfei Ren, Jiajia Wang, Zheng Chen   +7 more
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Experimental Investigation of Unloading-Induced Red Sandstone Failure: Insight into Spalling Mechanism and Strength-Weakening Effect

Advances in Civil Engineering, 2020
To study the effect of excavation unloading on hard rock failure, a series of true-triaxial compression tests, biaxial compression tests, and true-triaxial unloading compression tests (two different unloading rates) at different confining pressures was ...
Yong Luo, Fengqiang Gong, Dongqiao Liu
doaj   +1 more source

Time-effect properties and mechanisms of marble failure under different unloading rates

Yantu gongcheng xuebao, 2017
In the process of tunnel excavation, the failure properties of rock mass are obviously affected by unloading rates, and the failure properties show a clear time effect.
LI Xi-bing 1, 2, CHEN Zheng-hong 1,2, CAO Wen-zhuo 1, 2, TAO Ming 1, 2, ZHOU Jian 1, 2
doaj   +1 more source

Investigation of the Shear Mechanical Behavior of Sandstone with Unloading Normal Stress after Freezing–Thawing Cycles

Machines, 2021
Freezing–thawing action has a great impact on the physical and mechanical deterioration processes of rock materials in cold areas where environmental changes are very complicated.
Shuailong Lian, Jiashen Li, Fei Gan, Jing Bi, Chaolin Wang, Kun Zheng   +5 more
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Effect of intermediate principal stress and minimum principal stress unloading stress path and rate on energy evolution of sandstone under true triaxial compression

Meitan xuebao
In the process of deep coal mining, the unloading stress path and unloading rate of deep rock are complicated and changeable due to the influence of excavation and unloading.
Zhixi LIU, Guangming ZHAO, Xiangrui MENG, Zhihong QIN   +3 more
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Rock strength and deformation characteristics under different unloading rates

Shuili Shuiyun Gongcheng Xuebao, 2020
The excavation of rock mass engineering is essentially the unloading process of rock mass, and different unloading rates will significantly affect the strength and deformation characteristics of rock mass, which is of great significance to the safety and
QIAN Yajun, WU Yingli, PEI Weiwei, ZHU Yueyan   +3 more
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Deformation and Failure Characteristics of Loading and Unloading Rock Based on Volume Crack Strain

Frontiers in Earth Science, 2022
In order to study the laws of crack evolution in rock and explain its fracture instability mechanism, a series of laboratory tests were carried out with Jinping Marbles.
Xiaohui Liu, Xiaohui Liu, Xiaohui Liu, Yu Zheng, Yu Zheng, Yu Zheng, Jinyun Guo, Qijun Hao, Yang Xue, Yang Xue   +9 more
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Numerical Experimental Investigations of the Effect of Confining Pressure Unloading Rate on Sandstone Mechanical Properties

Taiyuan Ligong Daxue xuebao, 2023
Purposes This work is conducted to exclude the superimposed effect of natural rock specimen discreteness and multiple stress path conversion in test process on results, and to further investigate the influence mechanism of the confining pressure ...
Jian ZHANG, Liangliang GUO
doaj   +1 more source