Article
Engineering, Geological
Xu Chang, Xu Zhang, Faning Dang, Bafang Zhang, Fangqiang Chang
Summary: An experimental study was conducted to investigate the failure behavior of sandstone specimens containing a single flaw under true triaxial compression. The influences of the intermediate principal stress on cracking pattern, stress-strain response, and acoustic emission activities were analyzed. The results showed that the specimen strength increased with a higher intermediate principal stress. The crack initiation stress initially increased and then decreased with an increase in the intermediate principal stress. The flawed specimens typically failed due to anti-wing cracks, regardless of the flaw inclination angle and the intermediate principal stress. The proportion of shear cracks was higher than that of tensile cracks during the cracking process.
ROCK MECHANICS AND ROCK ENGINEERING
(2022)
Article
Materials Science, Ceramics
Xumei Zhao, Qinglong Fang, Caijuan Xia, You Xie, Di Wu, Xiaolian Chao, Zupei Yang
Summary: In this work, a simplified model based on Rayleigh's theory was developed to analyze the light scattering phenomenon caused by nanometric pores. The validity of this model was verified by experimental results, and it was found that the pore volume fraction is a more important parameter than pore size in determining the transparency of KNNB-xSm ceramics.
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
(2023)
Article
Geosciences, Multidisciplinary
Yongsong Lu, Peifeng Li, Wei Cai
Summary: This study examined the evolutionary characteristics of acoustic signals produced by granite under biaxial compression. The results showed distinct differences in precursors among different acoustic signals and a strong influence of intermediate principal stress on these precursors. The findings are significant for the prediction and warning of geological disasters in deep underground engineering.
FRONTIERS IN EARTH SCIENCE
(2023)
Article
Chemistry, Physical
Jia-Yu Liu, Wen-Jie Bao, Jia-Yu Zhao, Chang-Yu Zhou
Summary: In this paper, investigations on the fatigue crack growth behavior of commercial pure titanium were conducted with cruciform specimens. The modified solution of stress intensity factors for cruciform specimens containing mixed mode I-II crack was obtained based on finite element results. The experimental results showed that the maximum tangential stress criterion is suitable for predicting the crack initiation angles of mixed mode I-II crack. The biaxial load ratio was found to have an effect on the crack propagation angle and the fatigue crack growth rate.
Article
Engineering, Mechanical
Mael Zaid, Vincent Bonnand, Veronique Doquet, Vincent Chiaruttini, Didier Pacou, Pierre Depouhon
Summary: In this study, mode II fatigue crack growth under reversed shear and static biaxial compression was investigated in two bearing steels. The presence of aborted branches and the influence of compressive stress parallel to the main crack on crack growth were observed.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Chemistry, Multidisciplinary
Yuan Tian, Bangcheng Han, Xinyu Liu, Kai Shen, Jiangbo Li
Summary: Using experimental methods, the influence of hole and cracks on the mechanical properties and fracture characteristics of rock-like mortar materials under biaxial compression conditions was studied. Double crack specimens with hole depths ranging from 0-100 mm were prepared to investigate the strength and deformation characteristics under different lateral loads. The results showed that the depth of the holes greatly affected the strength and deformation of the specimens, with a significant decrease in peak stress observed at a hole depth of 60 mm.
APPLIED SCIENCES-BASEL
(2023)
Article
Construction & Building Technology
Vahab Sarfarazi, Kaveh Asgari, Shirin Jahanmiri, Mohammad Fatehi Marji, Alireza Mohammadi Khachakini
Summary: This study investigated the interaction between a notch and a micropore under uniaxial compression through computational and experimental methods. The results showed that the failure pattern affects the compressive strength, while the orientation of the notch and the condition of the pore impact the failure pattern formation. The numerical simulation and actual test results exhibited similar failure strengths.
ADVANCES IN CONCRETE CONSTRUCTION
(2022)
Article
Chemistry, Multidisciplinary
Kun Du, Minghui Liu, Chengzhi Yang, Ming Tao, Fukang Feng, Shaofeng Wang
Summary: This study investigates the mechanical characteristics and acoustic emission properties of granite, marble, and sandstone under biaxial compression tests. It shows that under biaxial confinement, the elastic moduli decrease, plasticity increases, and the biaxial compressive strength of rock initially increases then decreases with the increase of the intermediate principal stress. The study also found that the behavior of rocks under biaxial confinement is influenced by both the sigma(1) and sigma(2) stresses, and the failure modes of different rock types differ under such conditions.
APPLIED SCIENCES-BASEL
(2021)
Article
Metallurgy & Metallurgical Engineering
Wei Zhang, Wei-yao Guo, Zhi-qi Wang
Summary: This study investigates the influence of lateral pressure on the mechanical behavior of different rock types and analyzes the formation mechanism of macro-fracture surface. Results show that the brittleness and burst proneness of rock or coal material are stronger than that of gypsum material. The peak stress and elastic modulus increase with the increase of lateral pressure until a certain point, beyond which they decrease slightly or remain steady due to local failure.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2022)
Article
Construction & Building Technology
Md Jihad Miah, Francesco Lo Monte, Roberto Felicetti, Pierre Pimienta, Helene Carre, Christian La Borderie
Summary: Explosive spalling of concrete exposed to fire is the phenomenon of shards being expelled from the heated face during rapid heating. This can seriously compromise the integrity of reinforced concrete structures and expose reinforcing bars to flames. Factors such as heating rate, specimen geometry, concrete grade, and external loads influence the occurrence of fire spalling. This study focuses on the role of external loading combined with pore pressure and thermo-mechanical stresses in triggering spalling in normal-strength concrete.
CONSTRUCTION AND BUILDING MATERIALS
(2023)
Article
Engineering, Environmental
Mostafa Asadizadeh, Saeed Khosravi, Javad Karimi, Taghi Sherizadeh, Sanaz Vajedian, Mohammad Farouq Hossaini
Summary: In this paper, numerical investigations have been conducted on central-flawed cylindrical specimens to study their mechanical behavior and crack development. The results show that flaw angle, length, and aperture have an effect on the specimens' mechanical behavior. The cracking patterns resulting from the numerical simulations are consistent with those from experimental tests. It is concluded that flaw aperture scarcely affects failure patterns.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2022)
Article
Engineering, Geological
Ben-Guo He, Xiang-Rui Meng, Xia-Ting Feng, Sa Li, Yonghong Li
Summary: The failure modes of deep excavation are related to three-dimensional stresses. The effect of the intermediate principal stress (a2) on the failure of granite surrounding an underground powerhouse was examined. The stress a2 after excavation can help improve the failure brittleness and strength of the rock.
ENGINEERING GEOLOGY
(2022)
Article
Engineering, Geological
Fan Feng, Shaojie Chen, Yajun Wang, Wanpeng Huang, Zhenyu Han
Summary: Experimental tests on Miluo granite specimens reveal that as the intermediate principal stress σ2 increases, the failure mode shifts from shear to slabbing, exacerbating the extensional cracks. Analyzed through various methods, the peak unloading strength in true-triaxial conditions exhibits an initial increase followed by a decrease with increasing σ2.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Green & Sustainable Science & Technology
Baolin Xiong, Jia Sun, Yunmeng Zhao, Zhuangzhuang Wang, Zhiyuan Wang, Bo Chen
Summary: This study used digital image correlation method and acoustic emission equipment to observe the crack growth process in composite rock strata. The results showed that the strain field dispersion can be quantified using the covariance matrix parameter V, and the crack types can be identified based on the growth rate of V.
Article
Engineering, Geological
Qibin Lin, Ping Cao, Guanping Wen, Jingjing Meng, Rihong Cao, Zhiye Zhao
Summary: Research shows that the crack coalescence process in layered rock masses is influenced by joint angle and rock bridge angle, with seven types of crack coalescence identified that are not only related to angles but also influenced by rock layers.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2021)
Article
Chemistry, Physical
Miftah Hidayat, Mohammad Sarmadivaleh, Jos Derksen, David Vega-Maza, Stefan Iglauer, Jan Vinogradov
Summary: This study introduces a new methodology for measuring the zeta potential of silica in saturated CO2 solutions and reports the results. It shows that the pH of the solution is the only factor controlling the zeta potential, while temperature, CO2 pressure, and salt type affect the pH values.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2022)
Review
Engineering, Chemical
Adnan Aftab, Aliakbar Hassanpouryouzband, Quan Xie, Laura L. Machuca, Mohammad Sarmadivaleh
Summary: Geological H-2 storage plays a critical role in transitioning to a renewable hydrogen economy and achieving net-zero emissions. However, challenges such as H-2 leakage, microbial consumption, and storage capacity limitations exist.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Energy & Fuels
Zhiqi Zhong, Reza Rezaee, Matthew Josh, Lionel Esteban, Mohammad Sarmadivaleh
Summary: The study found that clays in shale formations provide additional conduction pathways, but their impact on water saturation is minimal. In contrast to conventional beliefs, it was shown that Archie's cementation exponent m does not monotonically increase with pore water conductivity, indicating that confining pressure and depth are the main causes of the non-Archie phenomenon.
JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING
(2022)
Article
Energy & Fuels
Shoaib Memon, Runhua Feng, Muhammad Ali, Masood Ahmed Bhatti, Ausama Giwelli, Alireza Keshavarz, Quan Xie, Mohammad Sarmadivaleh
Summary: It has been found that the interaction between supercritical CO2 and shale during hydraulic fracturing can alter the petrophysical properties of the rock and result in a reduction of fracture aperture, thereby decreasing the post-fracturing productivity of the rock.
Article
Geochemistry & Geophysics
Jimmy Xuekai Li, Reza Rezaee, Tobias M. Muller, Mahyar Madadi, Rupeng Ma, Mohammad Sarmadivaleh
Summary: Understanding seismic wave propagation in granular porous media is crucial for subsurface characterization. This study investigates the influence of wettability conditions on wave propagation in (partially) saturated granular porous media through laboratory experiments. The results reveal that the presence of liquid bridges in water-wetting conditions reinforces force chains and increases the P-wave velocity, leading to incoherent scattering. In contrast, gas-wetting conditions prevent the formation of liquid bridges, resulting in negligible incoherent scattering.
Article
Mathematics, Applied
Rui Xiang Wong, Elena Pasternak, Arcady Dyskin
Summary: Asymmetric friction refers to different magnitudes of friction resisting sliding in opposite directions. It has applications in geotechnical engineering and can be used in material design. Masses with asymmetric friction exhibit three types of oscillations. In cases of high degree of asymmetric friction, the spectra show peaks at both even and odd multiples of the driving frequency.
COMMUNICATIONS IN NONLINEAR SCIENCE AND NUMERICAL SIMULATION
(2023)
Article
Engineering, Multidisciplinary
Arcady Dyskin, Elena Pasternak
Summary: The examples presented in this passage demonstrate situations where the boundaries of frictional sliding or elastic shear propagate at the speed of the p-wave, potentially leading to confusion with instances of intersonic fracture propagation. The mechanism of intersonic sliding/shear zone propagation in these examples is controlled by the longitudinal wave velocity, resulting from the longitudinal elastic deformation of the surrounding material. Two simple models of intersonic sliding/shear zone propagation, involving frictional sliding and shearing of an elastic rod on a shear Winkler foundation, are discussed. The Winkler layer in these models can have either positive stiffness or apparent negative stiffness, with the sliding/shear zone propagating at the longitudinal wave velocity. In the case of negative stiffness, the deformation rapidly increases with time due to the influx of external energy required by the system to realize negative stiffness.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2023)
Review
Green & Sustainable Science & Technology
Yuxin Wang, Farhad Aslani, Arcady Dyskin, Elena Pasternak
Summary: The benefits of 3D concrete printing include reducing construction time and costs, providing design freedom, and being environmentally friendly. Combining this technology with Digital Twin technology can address the challenges and improve quality and sustainability.
Article
Mechanics
Rui Xiang Wong, Elena Pasternak, Arcady Dyskin
Summary: Asymmetric friction arises from material anisotropy and can cause intermittent tension and compression fractures. This study uses a model with multiple blocks to investigate the effects of asymmetric friction driven by harmonic oscillations. It is found that asymmetric friction produces velocity spectra with a frequency falloff of 1/f², distinguishing it from symmetric friction.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Environmental Sciences
Xiaolei Qu, Yunkai Zhang, Youran Chen, Youyang Chen, Chengzhi Qi, Elena Pasternak, Arcady Dyskin
Summary: This study proposes a coupled seepage-deformation model based on the numerical manifold method (NMM) to analyze the flow of groundwater in a fracture network considering the effects of seepage pressure and rock deformation. The global equilibrium equation of the system and the local factor of safety (FoS) of rock fractures are derived based on the principle of minimum energy. The simulation results verify the robustness and effectiveness of the proposed numerical model. Additionally, the method is applied to simulate a rock slope collapse caused by seepage effects, providing insights into the failure process of the slope.