您的检索：
学者姓名：范立峰
精炼检索结果：
年份
成果类型
收录类型
来源
综合
合作者
语言
清除所有精炼条件
摘要 ：
This study presents an investigation of joint stiffness determination by the frequency characteristics of transmitted wave in rock mass. First, the frequency characteristics of transmitted waves were investigated, and a method for determining joint stiffness based on frequency characteristics was proposed. Subsequently, the method was applied in a pendulum impact test to determine the joint stiffness of different joints. The stiffnesses of non -filled, sand -filled and clay-filled joints were determined. Finally, the effects of the amplitude and frequency of the incident wave on the accuracy of the joint stiffness determination method were discussed by comparing the predicted transmitted wave amplitude and energy with the measured transmitted wave amplitude and energy. The results show that the joint stiffness determination method can predict the transmitted wave amplitude and energy through a non -filled joint with more accuracy than a filled joint. In addition, for sand or clay-filled joints, the present method could satisfactorily predict the transmitted wave amplitude at a lower incident amplitude and a higher incident frequency. In contrast, when predicting the transmitted wave energy, a lower incident amplitude and frequency were more suitable.
关键词 ：
Transmitted wave Transmitted wave Joint stiffness determination Joint stiffness determination Rock mass Rock mass Frequency characteristics Frequency characteristics
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Fan, Lifeng , Wei, Xiuwen , Wang, Meng et al. The investigation of joint stiffness determination based on the frequency characteristics of transmitted wave in rock mass [J]. | JOURNAL OF APPLIED GEOPHYSICS , 2024 , 222 . |
| MLA | Fan, Lifeng et al. "The investigation of joint stiffness determination based on the frequency characteristics of transmitted wave in rock mass" . | JOURNAL OF APPLIED GEOPHYSICS 222 (2024) . |
| APA | Fan, Lifeng , Wei, Xiuwen , Wang, Meng , Yang, Qihao . The investigation of joint stiffness determination based on the frequency characteristics of transmitted wave in rock mass . | JOURNAL OF APPLIED GEOPHYSICS , 2024 , 222 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
The dynamic spalling characteristics of rock are important for stability analysis in rock engineering. This paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates. A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different temperatures. The dynamic spalling strengths of granite with different temperatures and strain rates were determined. A model was proposed to correlate the dynamic spalling strength of granite, high temperature and strain rate. The results show that the spalling strength of granite decreases with increasing temperature. Moreover, the spalling strength of granite with a higher strain rate is larger than that with a lower strain rate. The proposed model can describe the relationship among dynamic spalling strength of granite, high temperature and strain rate. (c) 2024 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ licenses/by-nc-nd/4.0/).
关键词 ：
Dynamic spalling characteristics Dynamic spalling characteristics High temperature High temperature Granite Granite Dynamic loading Dynamic loading Strain rate Strain rate
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Fan, L. F. , Yang, Q. H. , Du, X. L. . Spalling characteristics of high-temperature treated granitic rock at different strain rates [J]. | JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING , 2024 , 16 (4) : 1280-1288 . |
| MLA | Fan, L. F. et al. "Spalling characteristics of high-temperature treated granitic rock at different strain rates" . | JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING 16 . 4 (2024) : 1280-1288 . |
| APA | Fan, L. F. , Yang, Q. H. , Du, X. L. . Spalling characteristics of high-temperature treated granitic rock at different strain rates . | JOURNAL OF ROCK MECHANICS AND GEOTECHNICAL ENGINEERING , 2024 , 16 (4) , 1280-1288 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
This study investigates wave propagation of layered composite rock mass composed of multiple joints and assorted rock materials. Firstly, the effect of multiple-reflection between joints on wave transmission was explored by modifying the method of characteristics. Secondly, the superposition of direct and indirect transmission induced by multiple-reflection was analyzed. Waveform variations in wave transmission were compared across three different layered composite rock mass. Finally, the effects of wave parameters (frequency), joint parameters (stiffness and number), and rock parameters (wave impedance ratio) on both direct and indirect transmission induced by multiple-reflection were considered. The results indicate that the effect of indirect transmission induced by multiple-reflection on both particle velocity and stress transmission of waves cannot be ignored in many cases. The results further indicate that effect of indirect transmission induced by multiplereflection on both particle velocity and stress transmission coefficients decreases with increasing incident wave frequency, while it increases with increasing joint numbers. The effect initially increases and subsequently decreases with increasing joint stiffness. Furthermore, the effect of indirect transmission induced by multiplereflection on the particle velocity transmission coefficient increases while its effect on the stress transmission coefficient decreases with increasing wave impedance ratio.
关键词 ：
Transmission coefficient Transmission coefficient Multiple parallel joints Multiple parallel joints Wave transmission Wave transmission Layer composite rock mass Layer composite rock mass Modified method of characteristics Modified method of characteristics
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Fan, L. F. , Shi, X. Y. , Wang, M. et al. Wave transmission in layered composite rock mass comprising parallel joints and different rock materials [J]. | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES , 2024 , 181 . |
| MLA | Fan, L. F. et al. "Wave transmission in layered composite rock mass comprising parallel joints and different rock materials" . | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 181 (2024) . |
| APA | Fan, L. F. , Shi, X. Y. , Wang, M. , Jiang, F. . Wave transmission in layered composite rock mass comprising parallel joints and different rock materials . | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES , 2024 , 181 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
The present study investigated the dynamic fatigue damage of thermally shocked granite with cyclic impact load. Firstly, cyclic impact tests were performed with a split Hopkinson pressure bar (SHPB) device to study the dynamic stress-strain relationship of water-cooled granite at various temperatures and cyclic numbers. Subsequently, the dynamic stress, elastic modulus, maximum strain and strain rate affected by temperature and cyclic number were further discussed, the energy evolution and cumulative damage during cyclic impact were revealed. Finally, the crack propagation, failure mode and fatigue life (the maximum impact number) of granite were analyzed, a fatigue life prediction model was proposed. The results show that the dynamic stress, elastic modulus and transmitted energy of granite exponentially decrease, while the maximum strain, strain rate, reflection energy, absorption energy and cumulative damage exponentially increase as the cycle number increases with a fixed thermal treatment temperature. In addition, microcracks first appear in the longitudinal section, then develop into macrocracks and penetrate to cause granite failure as the impact number increases. Granite exhibits different failure modes after cyclic impact. Split tensile single fracture surface failure before 600 degrees C and multiple fracture surface failure at 800 degrees C. The fatigue life decreases as the temperature and impact pressure increase. Dynamic fatigue properties deterioration rate increases as cycle number increases.Microcracks develop into macrocracks and penetrate to cause granite failure.Single-fracture failure mode to multi-fracture failure mode occurs at 800 degree celsius.Fatigue life decreases as impact pressure and temperature increase.A model for predicting fatigue life is developed.
关键词 ：
Failure mode Failure mode Fatigue life Fatigue life Dynamic fatigue properties Dynamic fatigue properties Cycle impact Cycle impact Crack propagation Crack propagation
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Fan, L. F. , Li, H. , Xi, Y. et al. Effect of Cyclic Impact on the Dynamic Behavior of Thermally Shocked Granite [J]. | ROCK MECHANICS AND ROCK ENGINEERING , 2024 , 57 (7) : 4473-4491 . |
| MLA | Fan, L. F. et al. "Effect of Cyclic Impact on the Dynamic Behavior of Thermally Shocked Granite" . | ROCK MECHANICS AND ROCK ENGINEERING 57 . 7 (2024) : 4473-4491 . |
| APA | Fan, L. F. , Li, H. , Xi, Y. , Wang, M. . Effect of Cyclic Impact on the Dynamic Behavior of Thermally Shocked Granite . | ROCK MECHANICS AND ROCK ENGINEERING , 2024 , 57 (7) , 4473-4491 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
The long-term durability of basalt fiber-reinforced geopolymer concrete (BFRGC) in marine environments is importance for the development of sustainable construction practices. This study examines the long-term durability of basalt fiber-reinforced geopolymer concrete exposed to dry-wet cycles and immersion treatment in marine conditions. A geopolymer concrete with 1% fiber content was prepared and subjected to dry-wet cycles and immersion treatments in a 5% sulfate solution (Tehmina et al., 2014; Nasir et al., 2016; John et al., 2016) [13]. Density measurements, ultrasonic pulse velocity tests, and uniaxial compression tests were conducted on the BFRGC after various treatment durations. The mechanical properties of BFRGC were compared with geopolymer concrete without fibers in marine environments. Additionally, the changes in compressive strength of geopolymer concrete with and without fibers in different immersion environments were further discussed. Using low-field nuclear magnetic resonance (LF-NMR) technology, the variations in pore structure were also analyzed. The results show that the mechanical property loss from dry-wet cycles was greater than from immersion treatment. In BFRGC, strength decreased by 10.1% after 192 days of dry-wet cycles, compared to a smaller decrease of 5.6% in immersion environments. The inclusion of basalt fibers effectively enhances stability. When in dry-wet cycle tests, BFRGC strength decreased from 49.6 MPa to 44.6 MPa, a reduction of 10.1%. Conversely, geopolymer concrete without fibers dropped from 49.7 MPa to 42.1 MPa, a reduction of 15.5%. LF-NMR test results show that the porosity of geopolymer concrete without fibers increased by 21.6% and 17.5% in dry-wet cycles and immersion environments, respectively. In contrast, the porosity of BFRGC increased by 16.1% and 12.7%.
关键词 ：
Pore structure Pore structure Geopolymer concrete Geopolymer concrete Marine erosion Marine erosion Basalt fiber Basalt fiber
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Zhang, Y. H. , Zhong, W. L. , Fan, L. F. . Long-term durability investigation of basalt fiber-reinforced geopolymer concrete in marine environment [J]. | JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T , 2024 , 31 : 593-605 . |
| MLA | Zhang, Y. H. et al. "Long-term durability investigation of basalt fiber-reinforced geopolymer concrete in marine environment" . | JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T 31 (2024) : 593-605 . |
| APA | Zhang, Y. H. , Zhong, W. L. , Fan, L. F. . Long-term durability investigation of basalt fiber-reinforced geopolymer concrete in marine environment . | JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T , 2024 , 31 , 593-605 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
Waste sludge is a typical solid waste generated during construction excavation, which needs innocuity treatment and resource utilization. The development of geopolymer pavement base material using waste sludge is an economic and environmental method to realize the utilization of waste sludge. This manuscript aims to develop a geopolymer pavement base material using waste sludge and further evaluate its water stability under water soaking environment. The geopolymer specimens with different slag and waste sludge contents were prepared. The optimum mix proportion of geopolymer was determined by analyzing the effect of slag content on the ultimate compressive strength (UCS) and elastic modulus. The CO2 emissions and energy consumption of geopolymer was analyzed. The water stability of the geopolymer was further evaluated by analyzing the effects of soaking time on the density, wave velocity, mechanical properties and pore structure. The results show that the geopolymer with 50% slag content has the largest UCS and excellent strength development characteristics. The UCS of geopolymer pavement base material reaches 48.4 MPa and the CO2 emissions and energy consumption were reduced by 58.34% and 88.16% compared to C40 ordinary concrete. The results also show that the density, longitudinal wave velocity and porosity remain stable as soaking time increases. During the soaking process, the proportion of gel pores and transition pores decreases, while the proportion of capillary pores and air pores increases. The UCS of geopolymer pavement base material remains above 40 MPa after soaking for 90 days, showing excellent water stability. The geopolymer pavement base material has the potential application prospect in road engineering and emission reduction, which provides a feasible and cost-effective method for the utilization of waste sludge.
关键词 ：
Water stability Water stability Geopolymer Geopolymer Pore structure characteristics Pore structure characteristics Waste sludge Waste sludge Low-field nuclear magnetic resonance Low-field nuclear magnetic resonance
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Zhong, W. L. , Sun, Y. H. , Zhao, X. et al. Study on synthesis and water stability of geopolymer pavement base material using waste sludge [J]. | JOURNAL OF CLEANER PRODUCTION , 2024 , 445 . |
| MLA | Zhong, W. L. et al. "Study on synthesis and water stability of geopolymer pavement base material using waste sludge" . | JOURNAL OF CLEANER PRODUCTION 445 (2024) . |
| APA | Zhong, W. L. , Sun, Y. H. , Zhao, X. , Fan, L. F. . Study on synthesis and water stability of geopolymer pavement base material using waste sludge . | JOURNAL OF CLEANER PRODUCTION , 2024 , 445 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
The effective velocity of stress wave in rock masses with double -scale discontinuities subjected to in -situ stresses was investigated in the present study. An improved model that comprehensively considers the deformation of macrojoint and wave velocity of microdefected rock mass under in -situ stress was proposed to study the effective velocity of stress wave. The effect of in -situ stress on effective velocity was systematically analyzed using the presented model. The effect of the propagation distance, incident wave amplitude and incident wave frequency on effective velocity under in -situ stresses were further discussed and compared with the results of traditional study that disregards the influence of in -situ stress. The findings demonstrate that the small in -situ stresses have a substantial effect on the effective velocity. The effective velocity shows a trend of rapid increase followed by slow increase as increases of in -situ stress. Additionally, the effective velocity increases with propagation distance and amplitude. In the low and high -frequency regions, the effective velocity remains approximately at minimum and maximum values. A significant increase in the effective velocity is observed as the frequency increases in the mid -frequency region. However, it is noted that the effective velocity does not change significantly with increasing amplitude for sufficiently large in -situ stresses, and the influence of amplitude on the effective velocity can be disregarded. Furthermore, it is found that the effective velocity resulting from the present study is consistently larger than that resulting from the traditional study due to the effect of the in -situ stress. The findings of this investigation offer useful theoretical guidance for research into the effective velocity in deep rock mass.
关键词 ：
Macrojoint Macrojoint Stress wave Stress wave Effective velocity Effective velocity In -situ stress In -situ stress Microdefect Microdefect Rock mass Rock mass
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Wang, M. , Shang, J. L. , Fan, L. F. . Effective wave velocity in rock masses with double-scale discontinuities under in-situ stresses [J]. | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES , 2024 , 174 . |
| MLA | Wang, M. et al. "Effective wave velocity in rock masses with double-scale discontinuities under in-situ stresses" . | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES 174 (2024) . |
| APA | Wang, M. , Shang, J. L. , Fan, L. F. . Effective wave velocity in rock masses with double-scale discontinuities under in-situ stresses . | INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES , 2024 , 174 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
In high-temperature geological engineering applications, cyclic loads induced by various factors (e.g., earthquakes, excavation, and blasting) can exacerbate the thermal damage of engineered rock formations. Therefore, this study investigates the mechanical properties and microstructure evolution of thermally treated granite subjected to cyclic loading. First, the mechanical property variations of thermally treated granite under cyclic loading were studied through cyclic loading experiments. Subsequently, nuclear magnetic resonance (NMR) was employed to examine the microstructure evolution of thermally treated granite under cyclic loading. Lastly, the effects of cyclic loading on maximum strain, Young's modulus, pore size distribution, and porosity of thermally treated granite were discussed. Results indicate that at the same number of cycles, maximum strain increases with increasing temperature, while Young's modulus decreases. For granite subjected to the same thermal treatment, the maximum strain increases as the cyclic number increases, while Young's modulus decreases. Concurrently, porosity and fractal dimension initially decrease and then increase with a rising number of cycles.
关键词 ：
high temperature high temperature granite granite fatigue characteristics fatigue characteristics microstructure evolution microstructure evolution cyclic loading cyclic loading
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Fan, L. F. , Wang, Z. , Qiu, B. et al. Evolution of mechanical properties and microstructure in thermally treated granite subjected to cyclic loading [J]. | FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES , 2024 , 47 (4) : 1431-1444 . |
| MLA | Fan, L. F. et al. "Evolution of mechanical properties and microstructure in thermally treated granite subjected to cyclic loading" . | FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES 47 . 4 (2024) : 1431-1444 . |
| APA | Fan, L. F. , Wang, Z. , Qiu, B. , Wang, M. . Evolution of mechanical properties and microstructure in thermally treated granite subjected to cyclic loading . | FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES , 2024 , 47 (4) , 1431-1444 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
Seismic wave propagation across rock masses with thinlayer joints by the modified displacement discontinuity method (M-DDM) is of great importance for geophysical surveys. The M-DDM introduces a frequency-dependent effective stiffness to describe the dynamic stress-closure relationship of a thin-layer joint. We verify the accuracy of M-DDM in studying seismic wave propagation across rock masses with thin-layer joints. Subsequently, we evaluate the influence of the joint thickness and the incident wave frequency on M-DDM accuracy. We analyze the prediction error of the transmission coefficient obtained with M-DDM. The results demonstrate that the frequency-dependent effective joint stiffness increases with increasing incident wave frequency and decreases with increasing joint thickness. Compared with the traditional displacement discontinuity method (DDM), M-DDM more accurately predicts the transmission coefficients of seismic waves propagating across thin-layer based on M-DDM increases with increasing joint thickness and incident wave frequency and is always smaller than that obtained based on DDM. Therefore, the M-DDM can be used rock masses with thin-layer joints.
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | Wang, M. , Jia, L. , Li, G. Y. et al. A modified displacement discontinuity method for seismic wave propagation across rock masses with thin-layer joints [J]. | GEOPHYSICS , 2024 , 89 (4) : T227-T234 . |
| MLA | Wang, M. et al. "A modified displacement discontinuity method for seismic wave propagation across rock masses with thin-layer joints" . | GEOPHYSICS 89 . 4 (2024) : T227-T234 . |
| APA | Wang, M. , Jia, L. , Li, G. Y. , Wang, W. , Fan, L. F. . A modified displacement discontinuity method for seismic wave propagation across rock masses with thin-layer joints . | GEOPHYSICS , 2024 , 89 (4) , T227-T234 . |
| 导入链接 | NoteExpress RIS BibTex |
摘要 ：
本发明公开了一种用于隧道裂缝修补检测的波动信号放大听诊器装置，包含发射系统、信号放大测量系统两个部分。发射系统与信号放大系统通过信号传输线有线连接；通过采用预制的不同直径大小的气动式子弹从而得到不同初始波形、频率的入射波并能实时快速传输到超动态应变记录仪。该装置通过装置向隧道裂缝修补层释放冲击荷载，由混凝土衬砌层与修补材料的粘结面反射，将产生应力波反射波继续在介质中传播，当反射波传输到修补材料层与听诊界面交界处时，通过控制各层界面密度、纵波波速不同可以导致该层材料波阻抗不同，可使该传输信号放大数倍，经过多层界面放大最终会获得容易捕获接受的波信号，经过处理可以用以评价隧道裂缝修补质量的好坏。
引用：
复制并粘贴一种已设定好的引用格式，或利用其中一个链接导入到文献管理软件中。
| GB/T 7714 | 范立峰 , 邹弘扬 , 钟惟亮 et al. 一种用于隧道裂缝修补检测的波动信号放大听诊器装置 : CN202310600834.5[P]. | 2023-05-25 . |
| MLA | 范立峰 et al. "一种用于隧道裂缝修补检测的波动信号放大听诊器装置" : CN202310600834.5. | 2023-05-25 . |
| APA | 范立峰 , 邹弘扬 , 钟惟亮 , 杨崎浩 . 一种用于隧道裂缝修补检测的波动信号放大听诊器装置 : CN202310600834.5. | 2023-05-25 . |
| 导入链接 | NoteExpress RIS BibTex |
导出
| 数据： |
选中 到 |
| 格式： |
