Article
Thermodynamics
Huie Chen, Hua Du, Bin Shi, Wenchong Shan, Jiaqi Hou
Summary: This study investigated the changes in mechanical properties of hydrate bearing clayey sand reservoirs during the mining process and elucidated the microscopic mechanism. The experimental results demonstrated that the shear strengths of the samples decreased as the hydrate decomposed, and the effective cohesion was positively correlated with hydrate saturation degree. An expression for the linear growth of shear strength with effective confining pressure and hydrate saturation degree was established. Furthermore, the microstructures of the samples indicated that the hydrate and soil particles bore the external load together during the shear test, maintaining the pore morphology and enhancing the shear strength.
Article
Construction & Building Technology
Huihua Hu, Xing Zhang, Jianxin Qin, Hang Lin
Summary: This study investigates the influence of morphological characteristics on the shear mechanical properties of sawtooth joints through direct shear tests. The results show that the peak shear displacement of joints varies with increasing normal stress, and the shear strength of joints is positively correlated with normal stress. The study also establishes an empirical equation for the shear strength of joints considering the sawtooth angle. Furthermore, two modes of shear failure for serrated joints are identified. This research provides a theoretical reference for the prediction and prevention of geological disasters.
Article
Geochemistry & Geophysics
Samuel Webber, Timothy Little, Carolyn Boulton, James Biemiller, Marcel Mizera
Summary: This study investigates the behavior of low-angle normal faults (LANFs) and the influence of fault friction and cohesion on slip. The results show that LANFs with weak friction in the shallow crust favor slip localization onto a single fault, while slip at a site without a rider block can occur without a weak fault due to contrasting fault/crust cohesion and steepening of dip on the fault.
JOURNAL OF GEOPHYSICAL RESEARCH-SOLID EARTH
(2022)
Article
Engineering, Civil
Iago Da Silva Santos, Diego F. B. Sarzosa, Marcelo Paredes
Summary: This work presents a framework for modeling ductile fracture and successfully predicts the onset of fracture and tearing response in pressurized metallic components. The numerical predictions are in good agreement with measured data, and detailed analyses of the strain capacity of defected pipes are performed.
THIN-WALLED STRUCTURES
(2022)
Article
Environmental Sciences
Feng Gao, Jinxi Xie, Xin Xiong, Keping Zhou
Summary: This paper investigates the mechanical properties and strain softening model of rocks in cold regions after reaching peak strength. Freeze-thaw cycle tests and triaxial compression tests are conducted on green sandstone to obtain stress-strain curves. The deformation, strength, and post-peak characteristics of rocks are analyzed under freeze-thaw cycles and triaxial compression, and a constitutive model is established to accurately reflect the post-peak strain softening behavior.
ENVIRONMENTAL EARTH SCIENCES
(2023)
Article
Construction & Building Technology
Fan Yu, Daquan Sun, Guoqiang Sun, Senlin Ling, Mingjun Hu, Jianmin Ma
Summary: This study investigated the strength mechanism of pervious concrete and proposed a modified mix design method based on the Mohr-Coulomb failure criterion. It was found that the aggregate content coefficient (ACC) played a key role in balancing the permeability and strength of pervious concrete, without significantly affecting porosity, pore area, and fractal dimension. The strength of pervious concrete increased with the decrease of ACC, but the growth rate was gradually decreasing.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Engineering, Mechanical
Handong Liu, Jingjing Liu, Shiying Zhang, Lingyun Feng, Lei Qiu
Summary: To understand the impact of fracture on deformation and failure of soft rock, cement mortar specimens were used to simulate soft rock. Uniaxial and triaxial compression tests were conducted to study the stress-strain relationship and failure mode of fractured soft rock with different fracture angles and connectivity. A constitutive model and Mohr-Coulomb failure criterion for soft rock were established. The results showed that fractured soft rock had lower uniaxial compressive strength compared to intact soft rock. Fracture angles had significant effects on the failure mode, while the stress-strain curves remained similar.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Environmental Sciences
Hao Shi, Wenlong Chen, Houquan Zhang, Lei Song
Summary: This study proposes new concepts of pseudo-cohesion and pseudo-internal friction angle, which take into account both pre-peak and post-peak stage information. These parameters are derived as functions of maximum principal strain and are found to be related to the axial strain and confining pressure. The evolution of rock pseudo-shear strength parameters is closely related to the propagation of rock cracks.
ENVIRONMENTAL EARTH SCIENCES
(2023)
Article
Engineering, Civil
Mohatsim Mahetaji, Jwngsar Brahma, Rakesh Kumar Vij
Summary: The three-dimensional failure criterion is crucial for maintaining wellbore stability and addressing sand production issues. It proposes a new criterion with a linear relationship among the three in-situ principal stresses. Different failure criteria, such as the Mohr-Coulomb criterion, Hoek-Brown criterion, and Mogi-Coulomb criterion, have been used to understand rock failure under in-situ stresses. Among them, the extended Mohr-Coulomb failure criterion, considering the influence of intermediate principal stress, provides the best prediction of rock failure based on calibration and validation tests.
GEOMECHANICS AND ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Chunguang Li, Cuihua Li, Rong Zhao, Lei Zhou
Summary: The investigated strength criterion provides a more suitable approach for describing the ultimate stress capacity of rocks, considering the intermediate principal stress sigma(2). The nonlinear parabolic form of the criterion on the meridian plane makes it more applicable in rock mechanics compared to the linear Mohr-Coulomb failure criterion. In numerical analysis, the present criterion shows higher efficiency and reliability in solving corner problems than Mohr-Coulomb and Hoek-Brown criteria.
MECHANICS OF MATERIALS
(2021)
Article
Mechanics
Enkai Dai, Zhiqin Lv, Panpan Yuan, Guoqiang Liu, Ning Guo, Zhe Liu, Bingtao Tang
Summary: The modified isotropic Mohr-Coulomb fracture model and the anisotropic MMC fracture model were developed and calibrated to predict the ductile fracture behavior of QP980 steel sheet. The anisotropic fracture loci were obtained in various loading directions and the influence of plastic anisotropy on ductile fracture behavior was confirmed. The anisotropic MMC fracture model was validated through different tests, demonstrating its capability to predict ductile fracture behavior under different loading conditions.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Geological
Nan Yao, Xingmin Deng, Binyu Luo, Felix Oppong, Pengcheng Li
Summary: Traditional grouting technology is improved by adding an expansion agent to the grouting material, which provides compressive stress to stabilize the rock mass. The study reveals the mechanism of grouting reinforcement on rock mass strength and the failure mode after grouting. Experimental tests and numerical simulations show that expansive slurry grouting enhances the strength of the slurry-rock mass composite, and the failure primarily occurs in the weakest component.
ROCK MECHANICS AND ROCK ENGINEERING
(2023)
Article
Environmental Sciences
Yuan Li, Mingli Wei, Wei Wei, Wenwei Zhang, Lei Liu
Summary: This study investigates the role of oxidation-reduction potential (ORP) and pH in hydrocarbon-contaminated soils on shear characteristics. The results suggest that the concentration of hydrocarbons in contaminated soils can be linearly correlated with ORP/pH values, indicating the potential of ORP/pH as indicators for pollutant occurrence. The relationship between ORP/pH and shear strength shows a strong correlation, and a modified Mohr-Coulomb criterion using ORP/pH parameter improves the fitting effect of these relationships, verifying the reliability and feasibility of ORP/pH in assessing the shear strength of contaminated soil.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2023)
Article
Engineering, Mechanical
Yifan Chen, Hang Lin
Summary: The Hoek-Brown criterion is widely used in various fields. This study investigated the deterioration of Hoek-Brown parameters for freeze-thaw multi-fractured rock mass and proposed a new estimation method based on shear test. The values of GSI and mi were found to decrease with the increase of freeze-thaw cycles, following a negative exponential function model.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Geosciences, Multidisciplinary
Dian Kusumawati, David P. Sahara, Sri Widiyantoro, Andri Dian Nugraha, Muzli Muzli, Iswandi Imran, Nanang T. Puspito, Zulfakriza Zulfakriza
Summary: In this study, the fault instability criterion was applied to analyze the mechanism of the 2016 Mw 6.5 Pidie Jaya earthquake and its aftershock distribution, determining Panteraja as the causative fault. It was found that fault plane instability may play a role in seismic events in areas with high ΔCFS values, suggesting a potential influence on earthquake activity in different regions.
FRONTIERS IN EARTH SCIENCE
(2021)