Article
Engineering, Geological
Fei Xiong, Xinrong Liu, Xiaohan Zhou, Guangyi Lin, Dongshuang Liu, Yafeng Han, Bin Xu, Chunmei He, Zijuan Wang
Summary: The effects of intersecting angle and distribution orientation of fissures on the mechanical properties and failure characteristics of sandstone containing intersecting fissures were investigated. The crack initiation forms and failure modes were categorized and determined, and the crack evolution processes were studied. Approaches for quickly determining the crack initiation form and failure mode were proposed, and the crack evolution was predicted with acceptable precision.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2022)
Article
Engineering, Mechanical
Hao Zhou, Wanhong Guo, Yu Zhou
Summary: Static three-point bending tests and digital image correlation technique were used to investigate the strain and displacement fields on the surface of sandstone specimens containing a prefabricated semicircular bend crack. The distribution curve of stress intensity factor (SIF) and its change process with time were calculated. The results showed that the degree of stretching at the crack tip weakened and the shearing degree first increased and then decreased as the crack angle increased. In the I/II mixed fracture mode, the SIF fluctuated more in the early stage of loading, and the KI and KII distribution curves gradually stabilized and showed a crossover trend in the middle and late stages of loading.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Zhenyu Han, Diyuan Li, Tao Zhou, Jiarong Chen, Shijie Xie
Summary: This study investigates the effects of flaw inclination angle and pre-stress on the mechanical properties and fracture behavior of sandstone specimens under repetitive impact loadings. The results show that the repetitive impact counts and the cumulative absorbed energy peak at an axial pre-stress of 20-40 MPa. Digital image correlation (DIC) technique reveals high strain localizations around the flaw periphery. Wing and anti-wing cracks dominate in the cracking process during repetitive impact loadings.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Mechanics
Wenbo Wang, Haijian Su, Honghui Zhao, Liyuan Yu, Chen Wu
Summary: This study investigates the influence of grouting filling on the mechanical behavior and fracture characteristics of sandstones. The results show that increasing the filling rate and filling material strength can decrease the opening degree of the pre-notch and postpone the development of the fracture process zone. Moreover, the grouting filling effect has a pronounced impact on the crack propagation path and fracture surface morphology.
ENGINEERING FRACTURE MECHANICS
(2023)
Article
Engineering, Geological
Zhenyu Han, Jianchun Li, Diyuan Li, Jian Zhao
Summary: This study conducted a series of compression tests on sandstone specimens with surface flaws to investigate the effect of flaw depth on fracture behavior. The results showed that the strength and elastic modulus decreased with increasing flaw depth. The crack paths on the front and back surfaces were different, but became similar to specimens with penetrated flaws as the flaw depth increased.
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES
(2023)
Article
Engineering, Mechanical
Jiuzhou Huang, Lijuan Wang, Mao Zhou, Wen Hua, Yaozhong Xu, Dengsong Li, Shiming Dong
Summary: In this study, the fracture properties of sandstone under confining pressure and crack-filling environments were investigated. The results showed that the contribution of confining pressure to fracture toughness exhibited a linear increase trend, while the filling material weakened the fracture toughness to some extent.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Engineering, Mechanical
Zhenyu Han, Shijie Xie, Diyuan Li, Fan Feng, Wei Yuan
Summary: In this study, experimental tests were conducted to investigate the enhancing mechanism of inclusions in sandstone specimens containing flaws. The results showed that inclusions with a similar wave impedance to the sandstone matrix can significantly enhance the dynamic strength of flawed specimens, and the initiation and propagation behavior of cracks were also affected.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2022)
Article
Engineering, Mechanical
Fei Zhang, Liyun Yang, Peng Wei, Huanzhen Xie, Siyu Chen
Summary: This study investigates the spatial fracture behavior of red sandstone with non-unitary geometric weakly filled joints by conducting uniaxial compression experiments. The results show that the ductility of planar weak inclusions has a certain deterioration effect on the bearing capacity of the specimens. The three-dimensional spatial deformation and strain fields of the specimens are divided by the planar weak inclusions as the ductile length of the planar weak inclusions increases. The main failure mode of the specimens gradually evolves from shear failure to splitting failure.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Chemistry, Multidisciplinary
Changhao Xin, Yu Yang, Mengze Yang, Pengfei Liang, Yidan Sun, Huazhang Shen
Summary: This study investigates the stress-strain characteristics of compressed sandstone under different conditions and analyzes the evolution of the strain field using Digital Image Correlation technology. The relationship between the stress-strain curves and the strain field is preliminarily explained.
APPLIED SCIENCES-BASEL
(2022)
Article
Construction & Building Technology
Kunpeng Zhang, Chaolin Wang, Yu Zhao, Jing Bi
Summary: Insufficient vibration during the casting process often leads to the formation of cavities in mass concrete, which can affect its strength and deformation properties. However, the study of internal flaws in concrete is limited due to the difficulty in cutting specimens and observing the cracking processes. In this study, a novel method using camphor volatilization is proposed to prepare concrete samples with embedded flaws, and acoustic emission (AE) and computed tomography (CT) techniques are used to investigate the internal damage behavior. The results show that the presence of internal hole defects reduces the strength and deformability of the concrete, and the size of the cavity affects the peak strength, crack initiation stress, and deformation properties. The initiation of tension cracks in intact specimens primarily occurs near the boundaries, while in hollowed specimens, cracks initiate at the cavity perimeter and propagate towards the boundaries.
JOURNAL OF BUILDING ENGINEERING
(2023)
Article
Engineering, Geological
Rayan Dabloul, Bo Cheng Jin, Birendra Jha
Summary: Injection of fluids during wastewater disposal and geologic carbon sequestration leads to changes in rock's elastic and failure properties. To understand these changes, core-scale mechanical loading tests are conducted. Experimental and simulation studies on water-exposed and supercritical CO2-exposed Berea sandstones reveal the effects of pore fluid on crack propagation and stress distribution. The results provide insights into the failure behavior of rocks under induced stress.
Article
Engineering, Mechanical
Xiao-Ping Zhou, Sen-Lin Peng, Jian-Zhi Zhang, Jian-Nan Zhou, Filippo Berto
Summary: This study analyzes the effects of materials and confining pressures on the mechanical properties of flawed coarse and fine sandstone. It investigates the spatiotemporal acoustic emission (AE) events and ultimate failure modes of sandstone specimens with two flaws under biaxial compression, and observes the main macro-fracture surfaces using Electron Probe Microscope Analysis (EPEI) technique. The distribution characteristics of two AE indexes are also used to reveal the failure mechanism. The experimental results provide insight into the behavior of flawed rocks under complex stress loading conditions.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Environmental
Liang Zhang, Guilin Wang, Bolong Liu, Fan Sun, Ruiqiu Wang
Summary: The damage and deterioration of jointed rock mass under dry-wet cycling significantly affect rock fracture characteristics, posing a threat to the safety of reservoir bank slopes. This study conducted a series of uniaxial compression tests on jointed sandstone subjected to dry-wet cycles, quantitatively studying the deformation and cracking process, and identifying four failure modes after the dry-wet cycles. Based on the results, a fracture criterion that considers the effect of dry-wet cycling was established.
BULLETIN OF ENGINEERING GEOLOGY AND THE ENVIRONMENT
(2023)
Article
Engineering, Geological
Zelin Yan, Feng Dai, Yi Liu
Summary: This study proposes a novel testing method to characterize the dynamic shear property and failure mechanism of rocks. The results show that the dynamic shear strength of sandstone is rate-dependent, and the failure envelope of sandstone expands with increasing loading rate. The energy partition and microscopic shear cracking mechanism of the short beam compression (SBC) specimen are also analyzed.
JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING
(2023)
Article
Engineering, Mechanical
Yujie Feng, Haijian Su, Liyuan Yu, Chen Wu, Hao Wang
Summary: The complex response of rocks to high temperatures and mixed stress is a significant challenge in deep rock engineering. This study investigates the effect of notch offset and temperature on the fracture mechanism of sandstone through thermal treatment and mixed mode I-II loading tests. Using digital image correlation (DIC) technology, the complete process of rock fracture was analyzed and quantitatively characterized. The results show that thermal treatment reduces the peak load, fracture toughness, and fracture energy of sandstone, and increasing notch offset leads to significant increases in fracture toughness and fracture energy. The study also reveals the impact of high temperature on the microstructure and mineral phase transition of the sandstone samples through thermal analysis.
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2023)
Article
Materials Science, Characterization & Testing
Hao Wu, Guoyan Zhao, Pinnaduwa H. S. W. Kulatilake, Weizhang Liang, Enjie Wang
Article
Engineering, Mechanical
Hao Wu, Guoyan Zhao, Weizhang Liang
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2019)
Article
Computer Science, Interdisciplinary Applications
Hao Wu, Pinnaduwa H. S. W. Kulatilake, Guoyan Zhao, Weizhang Liang, Enjie Wang
COMPUTERS AND GEOTECHNICS
(2019)
Article
Engineering, Mechanical
Hao Wu, Pinnaduwa H. S. W. Kulatilake, Guoyan Zhao, Weizhang Liang
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2019)
Article
Engineering, Mechanical
Hao Wu, Guoyan Zhao, Weizhang Liang
THEORETICAL AND APPLIED FRACTURE MECHANICS
(2020)
Review
Geochemistry & Geophysics
Weizhang Liang, Bing Dai, Guoyan Zhao, Hao Wu
Article
Chemistry, Multidisciplinary
Hao Wu, Bing Dai, Guoyan Zhao, Ying Chen, Yakun Tian
APPLIED SCIENCES-BASEL
(2020)
Article
Mathematics
Weizhang Liang, Suizhi Luo, Guoyan Zhao, Hao Wu
Article
Geosciences, Multidisciplinary
Weizhang Liang, Asli Sari, Guoyan Zhao, Stephen D. McKinnon, Hao Wu
Article
Engineering, Geological
Weizhang Liang, Yuksel Asli Sari, Guoyan Zhao, Stephen D. McKinnon, Hao Wu
Summary: This study proposes five ensemble classifiers to estimate the probability of short-term rockburst risk, which were verified using 91 rockburst samples. The effects of different indicator combinations on prediction results were analyzed, and the proposed ensemble classifiers outperformed individual learners in overall performance, with accuracy-based and F-1-based classifiers being preferred for predicting short-term rockburst risk.
ROCK MECHANICS AND ROCK ENGINEERING
(2021)
Article
Metallurgy & Metallurgical Engineering
Hao Wu, Bing Dai, Li Cheng, Rong Lu, Guoyan Zhao, Weizhang Liang
Summary: This study investigated the mechanical properties and energy evolution of sandstone samples with and without circular cavities under impact loading tests. The presence of a cavity weakened the dynamic compressive strength and affected crack initiation and rock fragmentation.
MINING METALLURGY & EXPLORATION
(2021)
Article
Geochemistry & Geophysics
Qingliang Chang, Xingjie Yao, Chongliang Yuan, Qiang Leng, Hao Wu
Summary: When the coal seam floor contains a confined aquifer, water inrush disasters are highly likely to occur. The failure behavior of the coal seam floor in the paste filling working face can be assessed through a theoretical model and numerical analysis, with the filling interval and long-term strength of the filling body having significant impacts on the floor failure depth, stress and displacement distributions, and plastic zone.
Article
Engineering, Civil
Hao Wu, Dan Ma, A. J. S. Spearing, Guoyan Zhao
Summary: Understanding the failure phenomena and mechanisms of stress regime on tunnels is critical, as hazardous failure phenomena frequently occur in deep hardrock tunnels. This study systematically investigated the mechanical behavior of rock specimens with different numbers of openings under uniaxial compression, revealing the significant impact of the number of openings on the weakening effect of rock mechanical properties. The crack evolution process in specimens with openings includes tensile cracks, spalling cracks, and shear cracks, and the crack initiation mechanism can be fully explained based on the stress distribution law around the opening.
GEOMECHANICS AND ENGINEERING
(2021)
Article
Computer Science, Information Systems
Shaowei Ma, Zhouquan Luo, Hao Wu, Yaguang Qin