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Deformation and failure behaviour of straight-wall arched tunnels: effect of minimum principal stress under static stress and low-frequency disturbances SCIE
期刊论文 | 2025 , 95 (4) | ARCHIVE OF APPLIED MECHANICS
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Abstract :

To comprehensively investigate the effect of different minimum principal stresses on the stability of straight-wall arched tunnels, the static stress and low-frequency disturbances are applied in true triaxial loading tests, accompanied by acoustic emissions (AE) and internal image monitoring for damage. The results show that (1) increasing the minimum principal stress (along the axial direction of the tunnel) will improve tunnel stability, and (2) during the damage process of straight-wall arched tunnels, whether caused by static stress or low-frequency disturbances, the dissipated energy and AE count had demonstrated identical increasing trends in their numerical values. (3) When the straight-wall arched roadway had been damaged by low-frequency disturbances, the dissipated energy and AE count had increased gradually at first and then surged rapidly upon macroscopic damage, following a trend similar to an exponential function.Please check and confirm that the authors and their respective affiliations have been correctly identified and amend if necessary.We have confirmed the correctness of the authors and their affiliations

Keyword :

Acoustic emission Acoustic emission Dissipated energy Dissipated energy Image monitoring Image monitoring Minimum principal stress Minimum principal stress Straight-wall arched tunnel Straight-wall arched tunnel

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GB/T 7714 Li, Jianing , Hu, Jianhua , Gao, Pengfei et al. Deformation and failure behaviour of straight-wall arched tunnels: effect of minimum principal stress under static stress and low-frequency disturbances [J]. | ARCHIVE OF APPLIED MECHANICS , 2025 , 95 (4) .
MLA Li, Jianing et al. "Deformation and failure behaviour of straight-wall arched tunnels: effect of minimum principal stress under static stress and low-frequency disturbances" . | ARCHIVE OF APPLIED MECHANICS 95 . 4 (2025) .
APA Li, Jianing , Hu, Jianhua , Gao, Pengfei , Li, Binglei . Deformation and failure behaviour of straight-wall arched tunnels: effect of minimum principal stress under static stress and low-frequency disturbances . | ARCHIVE OF APPLIED MECHANICS , 2025 , 95 (4) .
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Control of Dust Pollution in Roadway Excavation and Optimization of Dust Removal Ventilation Parameters SCIE
期刊论文 | 2025 , 151 (3) | JOURNAL OF ENVIRONMENTAL ENGINEERING
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Rock drilling of face 1703 of section 185 of the Ashele Copper Mine was used to study dust migration, control, and reduction during excavation. Fluent numerical simulation and theoretical analysis methods were used to study dust pollution during excavation. An orthogonal experiment was carried out to optimize the ventilation parameters of the excavation face and assess the effect of the main parameters (the cross-section size of the air inlet duct, the location of the end face of the roadway inlet duct and air inlet rate of the excavation face) on dust reduction and control. The experimental results show that the ventilation parameters that were most significant in reducing and controlling the dust pollution were the excavation face air inlet rate. A range analysis showed that the most reasonable ventilation parameters were an air inlet rate of the excavation face of 13 m/s, the location of the end face of the roadway inlet duct of 4 m, and the cross-section size of the air inlet was 0.9 m. A comparison of the original and optimized ventilation schemes showed that the dust pollution in the excavation face and the respiratory area decreased significantly. The effectiveness of the optimized parameters was further checked through field tests. Finally, by dividing the activity areas of underground workers in the roadway and further calculating and analyzing the dust concentration in the breathing area of underground workers based on Python deep data mining, providing theoretical assistance for dust control.

Keyword :

Computational fluid dynamics (CFD) simulation Computational fluid dynamics (CFD) simulation Dust pollution Dust pollution Metal mines Metal mines Orthogonal experimental design Orthogonal experimental design Python deep parsing Python deep parsing

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GB/T 7714 Li, Binglei , Huang, Yixiong , Hu, Hongyuan et al. Control of Dust Pollution in Roadway Excavation and Optimization of Dust Removal Ventilation Parameters [J]. | JOURNAL OF ENVIRONMENTAL ENGINEERING , 2025 , 151 (3) .
MLA Li, Binglei et al. "Control of Dust Pollution in Roadway Excavation and Optimization of Dust Removal Ventilation Parameters" . | JOURNAL OF ENVIRONMENTAL ENGINEERING 151 . 3 (2025) .
APA Li, Binglei , Huang, Yixiong , Hu, Hongyuan , Long, Yi , Lv, Changlin , Wang, Zicheng . Control of Dust Pollution in Roadway Excavation and Optimization of Dust Removal Ventilation Parameters . | JOURNAL OF ENVIRONMENTAL ENGINEERING , 2025 , 151 (3) .
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Experimental investigations on the strength, acoustic emission and failure characteristics of thermally cycled flawed granite under biaxial compression EI
期刊论文 | 2025 , 215 | International Journal of Thermal Sciences
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In deep underground engineering projects, such as tunnel excavation and geothermal resource development, flawed rock masses frequently experience high-temperature (HT) and high-pressure environments. Understanding how intermediate principal stress (σ2) affects the mechanical behaviors and failure characteristics of thermally cycled flawed granite is intrinsically crucial. This study explores the correlations among the strength, acoustic emission and failure characteristics in thermally cycled flawed granite under biaxial compression with varying σ2. Results show that for a given temperature, the rock strength gradually increases as σ2 increases, but the σ2-dependency of strength approaches a critical state when σ2 attains a threshold. Notably, flawed granite subjected to 600 °C cyclic high temperature (CHT) shows the greatest sensitivity to σ2. Moreover, CHT and σ2 have a significant impact on the rock energy release efficiency. This study documents the breakage of rock bridges by thermally induced macrocracks at the flaw tips, which link with the pre-existing flaws to collectively dominate the cracking paths and failure mechanisms. Additionally, increased σ2 enhances shear mechanisms under room temperature (RT) and CHT400 °C conditions, while it diminishes shear mechanisms under CHT600 °C conditions. © 2025

Keyword :

Brittle fracture Brittle fracture Cracks Cracks Fracture mechanics Fracture mechanics High pressure engineering High pressure engineering High temperature applications High temperature applications High temperature engineering High temperature engineering Thermal Engineering Thermal Engineering Tunneling (excavation) Tunneling (excavation)

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GB/T 7714 Li, Bing-Lei , Sun, Tian , Zhang, Jian-Zhi et al. Experimental investigations on the strength, acoustic emission and failure characteristics of thermally cycled flawed granite under biaxial compression [J]. | International Journal of Thermal Sciences , 2025 , 215 .
MLA Li, Bing-Lei et al. "Experimental investigations on the strength, acoustic emission and failure characteristics of thermally cycled flawed granite under biaxial compression" . | International Journal of Thermal Sciences 215 (2025) .
APA Li, Bing-Lei , Sun, Tian , Zhang, Jian-Zhi , Long, Yi , Fu, Liang , Wang, Fei . Experimental investigations on the strength, acoustic emission and failure characteristics of thermally cycled flawed granite under biaxial compression . | International Journal of Thermal Sciences , 2025 , 215 .
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Influences of initial damage on the saturated granite failure characteristics under true triaxial stress with a free face: Insights into the rockburst prevention and control EI
期刊论文 | 2025 , 324 | Engineering Fracture Mechanics
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The moisture content and damage conditions significantly influenced the mechanical properties of hard rock, which are closely associated with rockburst tendency. However, there was limited prior knowledge of this issue due to the scarcity of physical experiments. In this study, a true triaxial experiment with a free face was conducted on granite specimens to investigate the influence of the initial damage and moisture content on rockburst control, utilizing AE monitoring, rock NMR imaging, and photography techniques. Experimental results showed that with the increase of the initial damage factor k and moisture content ω, the rock strength and AE activity decreased. The static crack extension concentrated around the initial damage zone, and the dynamic ejection decreased, leading to an increase in the fracture surface fracture index. When k and ω increased to a certain extent, the tensile mechanism was significantly reduced, and then the rockburst was efficiently prevented. The failure mechanism lay the initial damage zone weakened the strength of the granite matrix, inducing the FPZ nucleation and crack extension. Furthermore, the rockburst envelope of the granite was altered, with the reduced envelope area indicating a decrease in stored energy, resulting in the granite having insufficient energy to trigger a rockburst upon failure. In addition, due to the 'water wedge' effect, the moisture content further enhanced the weakening effect of the initial damage factor on rockburst tendency. © 2025

Keyword :

Brittle fracture Brittle fracture Cracks Cracks Ductile fracture Ductile fracture Fracture mechanics Fracture mechanics Moisture control Moisture control Tensile strength Tensile strength Triangulation Triangulation

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GB/T 7714 Li, Bing-Lei , Jiang, Jia-Yao , Zhang, Jian-Zhi et al. Influences of initial damage on the saturated granite failure characteristics under true triaxial stress with a free face: Insights into the rockburst prevention and control [J]. | Engineering Fracture Mechanics , 2025 , 324 .
MLA Li, Bing-Lei et al. "Influences of initial damage on the saturated granite failure characteristics under true triaxial stress with a free face: Insights into the rockburst prevention and control" . | Engineering Fracture Mechanics 324 (2025) .
APA Li, Bing-Lei , Jiang, Jia-Yao , Zhang, Jian-Zhi , Zheng, Lu , Long, Yi . Influences of initial damage on the saturated granite failure characteristics under true triaxial stress with a free face: Insights into the rockburst prevention and control . | Engineering Fracture Mechanics , 2025 , 324 .
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Failure characteristics of tunnel under the true triaxial condition: Role of a prefabricated flaw SCIE
期刊论文 | 2024 , 130 | THEORETICAL AND APPLIED FRACTURE MECHANICS
WoS CC Cited Count: 2
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Flaws such as faults, joints, and bedding planes often exist in natural rock masses, which pose significant safety hazards for tunnel excavation. We conducted a series of experimental tests to analyse the effect of the different flaw occurrences (intact, open-flaw, and filled-flaw) on the rockburst mode around a horseshoe-shaped tunnel. The destruction was monitored by continuous photo imaging (captured inside the tunnel) and acoustic emission (AE) monitoring. Test results show that: 1) Under different flaw occurrences, the rockburst mode is different. mainly for strain rockburst and fault slip rockburst 2) Strain rockburst produces more tensile cracks in the initial stage (I and II) and more shear cracks in the later stage (III, IV and V). However, the fault slip rockburst produces shear cracks from the beginning to the end. 3) The filled material inside the flaws can significantly enhance the stability of the surrounding rock and also inhibit the development of fault slip rockburst. The rockburst modes and mechanisms under different surrounding rock conditions have been verified by PFC.

Keyword :

Acoustic emission Acoustic emission Flaw occurrences Flaw occurrences PFC PFC Rockburst mode Rockburst mode Tunnel excavation Tunnel excavation

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GB/T 7714 Li, Jianing , Hu, Jianhua , Zhao, Yusong et al. Failure characteristics of tunnel under the true triaxial condition: Role of a prefabricated flaw [J]. | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 130 .
MLA Li, Jianing et al. "Failure characteristics of tunnel under the true triaxial condition: Role of a prefabricated flaw" . | THEORETICAL AND APPLIED FRACTURE MECHANICS 130 (2024) .
APA Li, Jianing , Hu, Jianhua , Zhao, Yusong , Zhao, Zhou , Chen, Yanliang , Li, Binglei . Failure characteristics of tunnel under the true triaxial condition: Role of a prefabricated flaw . | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 130 .
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Failure behaviors and acoustic emission characteristics of flawed granite of different grain sizes: Insights from true triaxial experiments with a free face SCIE
期刊论文 | 2024 , 131 | THEORETICAL AND APPLIED FRACTURE MECHANICS
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In this study, a group of experiments using true triaxial stress conditions with free face loading are performed on granite specimens with non-penetrating double flaws. The crack development and failure characteristics of these specimens are explored by integrating video of the free face and acoustic emission technology, with the combination of the four different intermediate principal stresses and three different grain sizes of the granite chosen as variables. First, surface flaws with a depth of 50 mm are found to have limited influence on the specimen's failure mode. The intermediate principal stress has a greater effect as it inhibits the development of surface cracks; however, surface cracks develop much more readily in coarse-grained specimens than in other specimens. Second, when the intermediate principal stress exceeds 10 MPa, the rock burst failure phenomenon occurs in the specimen. Third, irrespective of changes in the intermediate principal stress and granite specimen grain size, the specimens primarily fail by tensile-shear failure and shear failure. Extending inward from the free face in the sigma 3 direction, according to the failure types, the failure types can be classified into tensile failure, shear failure, and tensile-shear failure. Finally, using the stress state synthesis method, the specimen's stress state and crack distribution mechanism on the sigma 2 loading plane are analyzed.

Keyword :

Acoustic emission Acoustic emission Crack damage Crack damage Granite grain size Granite grain size Intermediate principal stress effect Intermediate principal stress effect Non -penetrating flaw Non -penetrating flaw

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GB/T 7714 Li, Binglei , Shi, Wenhao , Zhang, Huajin et al. Failure behaviors and acoustic emission characteristics of flawed granite of different grain sizes: Insights from true triaxial experiments with a free face [J]. | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 131 .
MLA Li, Binglei et al. "Failure behaviors and acoustic emission characteristics of flawed granite of different grain sizes: Insights from true triaxial experiments with a free face" . | THEORETICAL AND APPLIED FRACTURE MECHANICS 131 (2024) .
APA Li, Binglei , Shi, Wenhao , Zhang, Huajin , Long, Yi . Failure behaviors and acoustic emission characteristics of flawed granite of different grain sizes: Insights from true triaxial experiments with a free face . | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 131 .
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Spalling failure and fracturing of brittle sandstone containing rectangular cavity based on biaxial compression test and discrete element method SCIE
期刊论文 | 2024 , 158 | ENGINEERING FAILURE ANALYSIS
WoS CC Cited Count: 4
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Abstract :

Excavation of tunnel in hard brittle rock commonly induces disasters like spalling failure and rock burst, and numerous relevant theoretical, experimental and numerical studies are finished to detect the specific destruction mechanism. However, only a small number of researches focused on the excavation of underground mining stope, and the largest feature is the rectangular cavity and the gradient height of the cavity. Therefore, to mimic the failure procedure of the surrounding rock of the mining stope, six groups of rock samples containing various cavity heights are applied in the biaxial compression test (two types of confining pressures), and the PFC method is utilized to explain the failure mechanism in microscopic scale. The main results and conclusions are as follows: (1) The confining pressure directly affects the time relationship between the visible spalling failure and the typical AE burst incident. (2) As the cavity height increases, the spalling failure cannot cover the whole sidewall at once and transforms into localized destruction, which advances the corresponding initial appearance time. (3) The striped tensile failures distribute in the roof and bottom surrounding rock of rectangular cavity; tensile failures cover the whole spalling regions in sidewalls, while the shear failures are mainly concentrated in the lower part of the spalling areas. (4) When the cavity height is relatively large, the spalling failure in both sidewalls exhibits asymmetric distribution during the majority period of the test, and the final failure surface only shows an approximate symmetrical distribution.

Keyword :

Biaxial compression Biaxial compression PFC2D PFC2D Rectangular cavity Rectangular cavity Spalling failure Spalling failure

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GB/T 7714 Qi, Qi , Zhao, Yusong , Li, Binglei et al. Spalling failure and fracturing of brittle sandstone containing rectangular cavity based on biaxial compression test and discrete element method [J]. | ENGINEERING FAILURE ANALYSIS , 2024 , 158 .
MLA Qi, Qi et al. "Spalling failure and fracturing of brittle sandstone containing rectangular cavity based on biaxial compression test and discrete element method" . | ENGINEERING FAILURE ANALYSIS 158 (2024) .
APA Qi, Qi , Zhao, Yusong , Li, Binglei , Chen, Long . Spalling failure and fracturing of brittle sandstone containing rectangular cavity based on biaxial compression test and discrete element method . | ENGINEERING FAILURE ANALYSIS , 2024 , 158 .
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冷水循环下含孔洞页岩力学特征与破坏行为研究
期刊论文 | 2024 , 44 (10) , 125-132 | 矿业研究与开发
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冷水循环是岩石自然风化和损害的关键因素。为了探究层状页岩在冷水循环作用下的力学特性与损伤特性之间的复杂关系,开展了双轴压缩试验,研究了层状结构和冷水循环对含圆形孔洞的页岩力学性能的影响,分析了页岩的破坏模式。试验结果表明:冷水循环后,随着层理角度的增大,页岩的峰值强度曲线呈“V”形,层理角度为60°时峰值强度最低,折损率为38.55%;未经冷水循环的预处理条件下,岩样在破坏时均表现出拉伸和剪切复合型破坏的形态,冷水循环处理后,随着层理角度的增加,试样的破坏由贯穿层理的剪裂转变为沿层理面的剪切滑移;在冷水循环和层理角度的耦合作用下,页岩岩体的各向异性机制加强,导致岩石峰值强度降低。研究成果对岩土工程和地质工程生产具有重要意义。

Keyword :

冷水循环 冷水循环 各向异性 各向异性 层状结构 层状结构 破坏特征 破坏特征

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GB/T 7714 李兵磊 , 赵周 . 冷水循环下含孔洞页岩力学特征与破坏行为研究 [J]. | 矿业研究与开发 , 2024 , 44 (10) : 125-132 .
MLA 李兵磊 et al. "冷水循环下含孔洞页岩力学特征与破坏行为研究" . | 矿业研究与开发 44 . 10 (2024) : 125-132 .
APA 李兵磊 , 赵周 . 冷水循环下含孔洞页岩力学特征与破坏行为研究 . | 矿业研究与开发 , 2024 , 44 (10) , 125-132 .
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Uncertainty estimation of rock shear strength parameters based on Gaussian process regression EI
期刊论文 | 2024 , 45 , 415-423 | Rock and Soil Mechanics
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To address the issue of previous methods for estimating rock shear strength parameters lacking the ability to reflect and quantify uncertainties, a rock shear strength parameter uncertainty estimation method based on Gaussian process regression (GPR) is proposed for conducting probabilistic uncertainty analysis. Utilizing the rock strength parameter dataset, Gaussian process theory is employed to establish the mapping relationship between rock uniaxial compressive strength (UCS) and tensile strength (UTS) with shear strength parameters using various kernel functions. Through maximizing the logarithmic marginal likelihood function, the hyperparameter of the GPR model is optimized, and then the appropriate kernel function and GPR model are determined according to the prediction effect and uncertainty degree. The results indicate that under given UCS and UTS data, it is advisable to utilize the Matérn kernel function for developing the cohesion GPR model and the rational quadratic kernel function for constructing the internal friction angle GPR model. Compared with conventional machine learning methods, the GPR method not only provides accurate predictions of rock shear strength parameters but also offers insights into the degree of prediction uncertainty, demonstrating strong scientific validity and interpretability, thereby validating the feasibility and efficacy of the GPR model. © 2024 Biodiversity Research Center Academia Sinica. All rights reserved.

Keyword :

Gaussian distribution Gaussian distribution Jurassic Jurassic Maximum likelihood Maximum likelihood Rational functions Rational functions Regression analysis Regression analysis Shear flow Shear flow Shear strength Shear strength

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GB/T 7714 Zhang, Hua-Jin , Wu, Shun-Chuan , Li, Bing-Lei et al. Uncertainty estimation of rock shear strength parameters based on Gaussian process regression [J]. | Rock and Soil Mechanics , 2024 , 45 : 415-423 .
MLA Zhang, Hua-Jin et al. "Uncertainty estimation of rock shear strength parameters based on Gaussian process regression" . | Rock and Soil Mechanics 45 (2024) : 415-423 .
APA Zhang, Hua-Jin , Wu, Shun-Chuan , Li, Bing-Lei , Zhao, Yu-Song . Uncertainty estimation of rock shear strength parameters based on Gaussian process regression . | Rock and Soil Mechanics , 2024 , 45 , 415-423 .
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Mechanical and failure characteristics of flawed granite after high-temperature cycling: An experimental study using biaxial compression SCIE
期刊论文 | 2024 , 133 | THEORETICAL AND APPLIED FRACTURE MECHANICS
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Unveiling the mechanical and failure characteristics of flawed granite subjected to high-temperature (HT) cycles is essential for assessing the stability of underground engineering. There is limited advanced knowledge of the rock performance under HT cycles even today. To that end, biaxial compression experiments with the simultaneous acoustic emission (AE)-digital image correlation (DIC) monitoring are conducted on flawed granite containing the flaw pairs, with the emphasis on the influences of HT cycles on the mechanical and failure characteristics of flawed granite. Experimental results suggest that the rock strength is increased at 400 degrees C, regardless of the cycle number, while it is weakened at 600 degrees C, especially under the thermal cycles. By the coupling analysis of acoustic-optical-mechanical data, the levels of cracking in flawed granite are revealed as the process zone nucleation and quasi-static growth, along with the macrocrack initiation, propagation, and coalescence until the eventual failure, dictated by the stress shielding effect and stress amplification effect. The splitting crack, hook crack, and far-field network crack are reported for the first time. Moreover, the flawed granite at different temperatures transitions from tensile-dominated cracks to mixed tensile-shear (T-S) cracks. Besides, thermal cycling causes rock fatigue damage, and the alternating thermal stress generated by HT cycling promotes the initiation and propagation of microcracks, leading to the development and further intensification of thermally induced fracture.

Keyword :

Biaxial compression Biaxial compression Crack propagation Crack propagation Flawed granite Flawed granite High-temperature cycle High-temperature cycle Mechanical properties Mechanical properties

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GB/T 7714 Li, Bing-Lei , Sun, Tian , Zhang, Jian-Zhi et al. Mechanical and failure characteristics of flawed granite after high-temperature cycling: An experimental study using biaxial compression [J]. | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 133 .
MLA Li, Bing-Lei et al. "Mechanical and failure characteristics of flawed granite after high-temperature cycling: An experimental study using biaxial compression" . | THEORETICAL AND APPLIED FRACTURE MECHANICS 133 (2024) .
APA Li, Bing-Lei , Sun, Tian , Zhang, Jian-Zhi , Liu, Qian-Yu , Long, Yi . Mechanical and failure characteristics of flawed granite after high-temperature cycling: An experimental study using biaxial compression . | THEORETICAL AND APPLIED FRACTURE MECHANICS , 2024 , 133 .
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