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Analysis of blocking slurry diffusion parameters for a new self-starting drainage anchor cable

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Journal of Earth Science 2024年

作者： WANG Xu GE Qi Lü Chengcheng SHU Junwei SUN Hongyue Sino-Italy Ningbo Ecological Park Holding group Co. Ltd Ocean College Zhejiang University College of Civil Engineering and Architecture Zhejiang University School of Civil Engineering Nanjing Forestry University

A new self-starting drainage anchor that combines prestressed anchor cables with self-starting drainage is proposed. The novelty of the self-starting drainage method is the realization of the drainage and anchoring in the one inclined borehole. Reduction in the number of boreholes can greatly decrease the construction cost and duration of the project. The adverse effect of drilling construction disturbance on the slope is reduced. To tackle the possible blockage of the drainage cavity due to slurry leakage during the solidification process after finishing grouting in the blocking section. To this end， a theoretical equation for the slurry diffusion radius under slurry self-weight pressure boundary conditions is deduced. The result is verified for precision through comparison with numerical simulation. The findings reveal that the permeability coefficient of rock and soil mass makes the most significant impact on the slurry diffusion radius， succeeded by the length of the grouting blocking section， slurry initial setting time， and drilling inclination in descending order of influence. With the 5% mass ratio of a "711" type slurry quick-setting agent， the maximum slurry diffusion radius can be reduced from 0.925m to 0.449m， a reduction of 0.476m， which is comparatively more recommended.

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Unconfined compressive strength and failure behaviour of completely weathered granite from a fault zone

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Journal of Mountain Science 2024年第6期21卷 2140-2158页

作者： DU Shaohua MA Jinyin MA Liyao ZHAO Yaqian School of Civil Engineering and Architecture Henan University of Science and TechnologyLuoyang 471023China School of Resources and Safety Engineering Central South UniversityChangsha 410083China China Railway 18th Bureau group Co. LtdTianjin 300222 China China General Nuclear Power Corporation Shenzhen 518031China

Understanding the strength characteristics and deformation behaviour of the tunnel surrounding rock in a fault zone is significant for tunnel stability *** this study,a series of unconfined compression tests were conducted to investigate the mechanical characteristics and failure behaviour of completely weathered granite(CWG)from a fault zone,considering with height-diameter(h/d)ratio,dry densities(ρd)and moisture contents(ω).Based on the experimental results,a regression mathematical model of unconfined compressive strength(UCS)for CWG was developed using the Multiple Nonlinear Regression method(MNLR).The research results indicated that the UCS of the specimen with a h/d ratio of 0.6 decreased with the increase ofω.When the h/d ratio increased to 1.0,the UCS increasedωwith up to 10.5%and then ***ρd is conducive to the improvement of the UCS at anyω.The deformation and rupture process as well as final failure modes of the specimen are controlled by h/d ratio,ρd andω,and the h/d ratio is the dominant factor affecting the final failure mode,followed byωandρ*** specimens with different h/d ratio exhibited completely different fracture mode,i.e.,typical splitting failure(h/d=0.6)and shear failure(h/d=1.0).By comparing the experimental results,this regression model for predicting UCS is accurate and reliable,and the h/d ratio is the dominant factor affecting the UCS of CWG,followed byρd and thenω.These findings provide important references for maintenance of the tunnel crossing other fault fractured zones,especially at low confining pressure or unconfined condition.

关键词： Fault fracture zone Completely weathered granite(CWG) Unconfined compression strength(UCS) Multiple nonlinear regression model

Improvements in properties of NdFeB magnets obtained via magnetron sputtering and thermal diffusion

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Journal of Rare Earths 2024年第9期42卷 1710-1716页

作者： Jin Tang Weichao Huang Dan Li School of Electronic Engineering Guangxi University of Science and Technology China Rare Earth (Guangxi) Jinyuan Rare Earth New Materials Co. Ltd China Rare Earth group Co. Ltd. Center of Experimental Teaching for Common Courses Panzhihua University

The grain boundary diffusion process（GBDP） of Dy and DyAl on sintered NdFeB magnets was conducted via magnetron-sputtering deposition of Dy and DyAl films to enhance coercivity(Hcj),The magnetic properties,microstructure and anti-corrosion properties of Dy-surface-alloying NdFeB magnets obtained via magnetron sputtering and thermal diffusion were *** Hcjof the Dy95Al5-NdFeB magnet increases by 32.68%,while the remanence declines ***,X-ray diffraction and microstructural analysis confirm the formation of Dy-rich shells,the higher-magnetic-anisotropy field of hard(NdxDy1-x)2（FeAl）14B magnetic phases and an optimised grain boundary structu re,contributing to the Hcjenhancement of the *** elemental distribution and diffusion mechanism of the magnets are also ***,the corrosion resistance of the Dy95Al5-NdFeB magnet is substantially improved by enhancing the electrochemical stability and optimising the distribution and morphology of the intergranular *** findings of this study are of substantial importance in the development of low-heavy rare-earth sintered NdFeB magnets.

关键词： Magnetron sputtering NdFeB Rare earths microstructure Magnetic property Corrosion resistance

Geological conditions and reservoir characteristics of various shales in major shalehosted regions of China

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China Geology 2024年第1期7卷 138-149页

作者： Shu-jing Bao Tian-xu Guo Jin-tao Yin Wei-bin Liu Sheng-jian Wang Hao-han Li Zhi Zhou Shi-zhen Li Xiang-lin Chen The Key Laboratory of Unconventional Petroleum Geology China Geological SurveyMinistry of Natural Resources100083 BeijingChina Oil and Gas Survey China Geological Survey100083 BeijingChina Research Institute of Yanchang Petroleum(group)CO.LTD 710076 Xi’anChina

China is home to shales of three facies:Marine shale,continental shale,and marine-continental transitional *** types of shale gas are associated with significantly different formation conditions and major controlling *** study compared the geological characteristics of various shales and analyzed the influences of different parameters on the formation and accumulation of shale *** general,shales in China’s several regions exhibit high total organic carbon(TOC)contents,which lays a sound material basis for shale gas *** strata generally show high degrees of thermal *** contrast,continental shales manifest low degrees of thermal evolution,necessitating focusing on areas with relatively high degrees of thermal evolution in the process of shale gas surveys for these *** shales of the Wufeng and Silurian formations constitute the most favorable shale gas reservoirs since they exhibit the highest porosity among the three types of *** shales are followed by those in the Niutitang and Longtan *** contrast,the shales of the Doushantuo,Yanchang,and Qingshankou formations manifest low ***,the shales of the Wufeng and Longmaxi formations exhibit high brittle mineral *** a low siliceous mineral content,the shales of the Doushantuo Formation feature a high carbonate mineral content,which can increase the shales’brittleness to some *** marine-continental transitional shales,where thin interbeds of tight sandstone with unequal thicknesses are generally found,it is recommended that fracturing combined with drainage of multiple sets of lithologic strata should be employed to enhance their shale gas production.

关键词： Shale gas Marine shale Continental shale Marine-continental transitional shale Neoproterozoic-Cretaceous strata Geological conditions Reservoir characteristics Petroleum geological survey engineering

Study on hydrodynamic diffusion law of the swelling particle slurry in karst pipeline

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Particuology 2024年第4期87卷 218-231页

作者： Bingchuan Cheng Haibo Li Guangming Pan Runhuai Deng Yu'an Gong Shujun Xu Kun Zhou Zhuo Zheng School of Civil Engineering Geotechnical and Structural Engineering Research CenterShandong UniversityJinan250061China The Fourth Prospecting of Shandong Coal Geology Bureau Weifang261000China China Railway 14th Bureau group Corporation Limited Jinan250101China School of Trafic Engineering Shandong Jianzhu University.Fengming RoadLingang Development ZoneJinan250101China

The swelling particle grouting material has demonstrated remarkable plugging effectiveness in high-pressure and large-flow burst water within karst ***,current research on the rheolog-ical model,flow computation theory,and plugging mechanism of this material is *** conven-tional grouting slurry diffusion process,using the liquid-liquid two-phase flow method,fails to accurately simulate high solubility slurry and particle *** address these limitations,this study established a precise constitutive model to describe the swelling particle slurry diffusion process in dynamic ***,a coupling calculation method was proposed to analyze the spatiotemporal heterogeneity of viscosity during slurry diffusion by considering the migration of slurry and the changes in *** investigate the interaction between particle swelling and flow field changes,a Compu-tational Fluid Dynamics-Discrete Element Method(CFD-DEM)coupling model was developed for the diffusion of swelling particle *** is demonstrated that slurry viscosity increases exponentially within the diffusion front as the particle swelling rate rises,and the drag force exhibits an intriguing behavior of initially increasing and then decreasing as the slurry flows through the ***-more,the CFD-DEM coupling model proved to be more accurate in describing viscosity distribution and diffusion distance compared to the finite element *** primary objective of this paper is to reveal the plugging mechanism and provide theoretical support for the engineering application of the swelling particle grouting material.

关键词： Karst pipeline Swelling particle grouting material Dynamic water diffusion Spatiotemporal variation of viscosity CFD-DEM coupling model

Research on Visual Operation and Guide System of Railway Four⁃electric Engineering Construction

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International Journal of Plant Engineering and Management 2024年第1期29卷 47-54页

作者： PANG Zhining XU Tianyi WU Xusheng JIN Wenxin Design&Research Institute China Railway Electrification Bureau(Group)Co.Ltd.Beijing 100166China

The visualization operation of railway four-electric engineering construction is an important part in railway′s construction,which plays a critical role in improving operation efficiency and it is smoothly finished on railway four-electric majors′professional *** to the typical high-speed railway project construction′s technology,these four-electric professional construction′s technology scheme are made into construction method′s video,according to the technology plan′s characteristics of professional,visualization and information,under the premise of improving the efficiency about professional project management and construction of the railway four-electric project,the critical technology problems of railway four-electric project are *** the same time,it also improves efficiency of BIM model′s construction,the cooperation management′s efficiency of construction process,and the ability of integrating model information.

关键词： four electric platform BIM railway process method

Thermodynamic performance of a cryogenic energy storage system based on natural gas liquefaction

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Energy Storage and Saving 2024年第1期3卷 23-29页

作者： Xiaoqiao Qin Hongbo Tan Wei Shen Na Wen Yu Sun Department of Refrigeration and Cryogenic Engineering School of Energy and Power EngineeringXi’an Jiaotong UniversityXi’an710049China Yingde Gases(Shanghai)group Company Limited Shanghai210035China Technical Institute of Physics and Chemistry CASBeijing100190China

Cryogenic energy storage(CES)is a viable method for grid-scale electrical energy *** the high energy density and mature application of liquefied natural gas(LNG),we proposed an LNG cryogenic energy storage(LNGES)system.A steady-state process model of the LNGES system was established using Aspen *** effects of the natural gas composition and key operating parameters such as the charging pressure,discharging pressure,throttling temperature,and liquid storage pressure on the system performance were investigated.A multi-parameter genetic algorithm model built using the MATLAB software was used to optimize the LNGES system to optimize the round-trip efficiency(RTE).Then,an exergy analysis of the optimal configuration was *** results suggested that the LNGES system could achieve optimal RTE and exergy efficiency values of 60.14%and 71.64%,*** destruction mainly occurred during the compression,throttling,expansion,and heat *** proposed LNGES system could be a promising candidate for the large-scale application of CES technology in power grids and gas networks.

关键词： Cryogenic energy storage Liquefied natural gas Genetic algorithm optimization Round-trip efficiency Exergy analysis

An Optimization Method for Seismic Reliability of Regional Road Networks

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Journal of Traffic and Transportation Engineering(English Edition) 2024年

作者： Fei Wang Minqing Zhu Hongjun Cui Qihang Zhou Xinyu Sun Di Zhou Xinwei Ma School of Architecture and Art Design Hebei University of Technology School of Civil and Transportation Engineering Hebei University of Technology Tianjin Sino-German University of Applied Sciences Hebei Expressway group Limited Shi Huang Branch

To enhance the efficacy of seismic reliability assessments within regional road networks， this study introduces the constructs of Forbidden Edge Sets and Iterable Edge Sets within the framework of the Quick Fixed-node Unconnected Subgraph Algorithm (QFUS). Through optimization of the subgraph iteration process， the Quick Subgraph Algorithm (QSA) has been developed， exhibiting a diminished temporal complexity. Examining the topological architecture of road network systems， this research proposes the notion of road unit criticality. The corresponding equations have been formulated and empirically validated. Addressing the seismic optimization challenge of road networks， an optimization model has been constructed， and the Additive Edge Method has been introduced， aiming to minimize the requisite investment for enhancements. The algorithms QSA and the Additive Edge Method were applied to the road network in the vicinity of Zhangjiakou for empirical analysis. The results indicate that the QSA algorithm enhances the computational efficiency of network reliability by 33.04% in comparison to the QFUS algorithm. The metric of road unit criticality effectively quantifies the influence of various road unit reinforcement strategies on the seismic reliability enhancement of road network systems. The Additive Edge Method proposed herein is shown to minimize the analytical scope required for road units within the network and achieves cost minimization for seismic optimization of the road network. The scientific validity and logical soundness of the Additive Edge Method have been corroborated through the application of the control variable technique.

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Formation and ecological response of sand patches in the protection system of Shapotou section of the Baotou-Lanzhou railway,China

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Journal of Arid Land 2024年第2期16卷 298-313页

作者： DUN Yaoquan QU Jianjun KANG Wenyan LI Minlan LIU Bin WANG Tao SHAO Mei Key Laboratory of Desert and Desertification Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China College of Urban and Environmental Sciences Northwest UniversityXi'an 710100China Zhongwei Works Section of China Railway Lanzhou Bureau group Company Limited Zhongwei 755000China

The development of bare patches typically signifies a process of ecosystem *** the protection system of Shapotou section of the Baotou-Lanzhou railway,the extensive emergence of bare sand patches poses a threat to both stability and ***,there is limited knowledge regarding the morphology,dynamic changes,and ecological responses associated with these sand ***,we analyzed the formation and development process of sand patches within the protection system and its effects on herbaceous vegetation growth and soil nutrients through field observation,survey,and indoor analysis *** results showed that sand patch development can be divided into three stages,i.e.,formation,expansion,and stabilization,which correspond to the initial,actively developing,and semi-fixed sand patches,*** average dimensions of all sand patch erosional areas were found to be 7.72 m in length,3.91 m in width,and 0.32 m in *** actively developing sand patches were the largest,and the initial sand patches were the *** the stage of formation and expansion,the herbaceous community composition changed,and the plant density decreased by more than 50.95%.Moreover,the coverage and height of herbaceous plants decreased in the erosional area and slightly increased in the depositional lobe;and the fine particles and nutrients of soils in the erosional area and depositional lobe showed a decreasing *** the stabilization phases of sand patches,the area from the inlet to the bottom of sand patches becomes initially covered with *** and 0-2 cm surface soil condition improved in the erosional area,but this improvement was not yet evident in the depositional *** such as disturbance,climate change,and surface resistance to erosion exert notable influences on the formation and dynamics of sand *** results can provide evidence for the future treatment of sand patches and the management of the pro

关键词： railway protection system sand patch morphology vegetation characteristic soil property