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中国岩溶 1996年第4期 89+99-89+99页

作者： wang Hongtao wang enzhi (department of hydraulic engineering,Qinghua University) Li Shixiong (Hebei Provincial Bureau of Geololgy and Mineral Resources)

漓江综合治理的对策与建议——漓江综合治理问题研讨会综述日前由市科协主持，市科协学会部和市老科协针对旅游立市中的难点——漓江综合治理问题，共同组织召开了专题研讨会。参加研讨会的有长年从事水文地质、工程地质、水资源、水力... 详细信息

漓江综合治理的对策与建议——漓江综合治理问题研讨会综述日前由市科协主持，市科协学会部和市老科协针对旅游立市中的难点——漓江综合治理问题，共同组织召开了专题研讨会。参加研讨会的有长年从事水文地质、工程地质、水资源、水力电力、环境保护、城市规划等专业技术...

关键词： Karst land collapse Mechanism of formation Static conditions Dynamic conditions Overlap analysis

离散单元法的饱和/非饱和渗流模型及其实验验证

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水力发电学报 2003年第3期22卷 34-39页

作者：周庆科金峰王恩志徐艳杰清华大学水利水电工程系北京100084

本文基于时步显式迭代的方法 ,提出了离散单元法的饱和 /非饱和渗流模型 ,使裂隙岩体中的渗透效应直接参与离散单元法的显式平衡迭代 ,而无需求解大规模的渗透方程组。利用该模型对饱和 /非饱和裂隙网络实验进行了数值模拟 ,其饱和区和... 详细信息

本文基于时步显式迭代的方法 ,提出了离散单元法的饱和 /非饱和渗流模型 ,使裂隙岩体中的渗透效应直接参与离散单元法的显式平衡迭代 ,而无需求解大规模的渗透方程组。利用该模型对饱和 /非饱和裂隙网络实验进行了数值模拟 ,其饱和区和非饱和区的渗透荷载分布与实测结果有很好的一致性。本文提出的模型具备应用于暴雨入渗条件下岩质边坡的变形和稳定分析的重要前景。

关键词：渗流计算饱和/非饱和裂隙渗流离散单元法域接触

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Scale-space effect and scale hybridization in image intelligent recognition of geological discontinuities on rock slopes

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Journal of Rock Mechanics and Geotechnical engineering 2024年第4期16卷 1315-1336页

作者： Mingyang wang enzhi wang Xiaoli Liu Congcong wang State Key Laboratory of Hydro-science and engineering Tsinghua UniversityBeijing100084China

Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock *** and efficient acquisition of GD networks is essential for characterizing and understanding the progressive damage mechanisms of slopes based on monitoring image *** by recent advances in computer vision,deep learning(DL)models have been widely utilized for image-based fracture *** multi-scale characteristics,image resolution and annotation quality of images will cause a scale-space effect(SSE)that makes features indistinguishable from noise,directly affecting the ***,this effect has not received adequate ***,we try to address this gap by collecting slope images at various proportional scales and constructing multi-scale datasets using image processing ***,we quantify the intensity of feature signals using metrics such as peak signal-to-noise ratio(PSNR)and structural similarity(SSIM).Combining these metrics with the scale-space theory,we investigate the influence of the SSE on the differentiation of multi-scale features and the accuracy of *** is found that augmenting the image's detail capacity does not always yield benefits for vision-based recognition *** light of these observations,we propose a scale hybridization approach based on the diffusion mechanism of scale-space *** results show that scale hybridization strengthens the tolerance of multi-scale feature recognition under complex environmental noise interference and significantly enhances the recognition accuracy of *** also facilitates the objective understanding,description and analysis of the rock behavior and stability of slopes from the perspective of image data.

关键词： Image processing Geological discontinuities Deep learning Multi-scale Scale-space theory Scale hybridization

Three-dimensional hydro-mechanical coupling numerical simulation of shield-driven cross-river twin tunnels:A case study

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Underground Space 2024年第3期16卷 106-125页

作者： Chengwen wang Xiaoli Liu Danqing Song enzhi wang Guohui Yan Ran Zhou department of hydraulic engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China YSD Rail Transit Construction Company Limited Guangzhou 510630China

With the rapid development of urban underground space,the construction of shield-driven cross-river twin tunnels is increasing,and the complex hydro-mechanical coupling effects and twin-tunnel interactions bring huge construction risks to such projects,which have attracted more and more *** study aims to understand the excavation effects induced by shield driving of cross-river twin tunnels through numerical simulation.A refined three-dimensional numerical model based on the fully coupled hydro-mechanical theory is *** model considers the main components of the slurry pressure balance shield(SPBS)machine,including support force,jacking thrust,grouting pressure,shield-rock interaction and lining-grouting interaction,as well as the detailed construction *** purpose is to examine the excavation effects during construction,including rock deformation around tunnels,the change in pore pressure,and the response of the *** results show the influence range of twin-tunnel excavation on rock deformation and pore pressure,as well as the modes of lining *** addition,this study also systematically investigates the effects of water level fluctuation and burial depth on twin-tunnel *** results indicate that the increase of water level or burial depth will enhance the excavation effects and strengthen the twin-tunnel *** results provide useful insights for estimating the construction impact range and degree of twin tunnels,and serve as basic references for the design of cross-river twin tunnels.

关键词： Numerical modeling Twin tunnels Crossing river Hydro-mechanical coupling Lining response

Graph theoretical analysis of limestone fracture network damage patterns based on uniaxial compression test

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Journal of Rock Mechanics and Geotechnical engineering 2024年第9期16卷 3485-3510页

作者： Mingyang wang Congcong wang enzhi wang Xiaoli Liu Xiao Li State Key Laboratory of Hydro-science and engineering Tsinghua UniversityBeijing100084China department of Automation Tsinghua UniversityBeijing100084China Beijing Huairou Laboratory Beijing101400China Institute of Geology and Geophysics Chinese Academy of ScienceBeijing100029China

The topological attributes of fracture networks in limestone,subject to intense hydrodynamics and intricate geological discontinuities,substantially influence the mechanical and hydraulic characteristics of the rock *** dynamical evolution of fracture networks under stress is crucial for unveiling the interaction patterns among ***,existing models are undirected graphs focused on stationary topology,which need optimization to depict fractures'dynamic development and rupture *** compensate for the time and destruction terms,we propose the damage network model,which defines the physical interpretation of fractures through the ternary *** focus primarily on the evolution of node types,topological attributes,and motifs of the fracture network in limestone under uniaxial *** expose the varying behavior of the nodes'self-dynamics and neighbors'adjacent dynamics in the fracture *** approach elucidates the impact of micro-crack behaviors on large brittle shear fractures from a topological perspective and further subdivides the progressive failure stage into four distinct phases(isolated crack growth phase,crack splay phase,damage coalescence phase,and mechanical failure phase)based on the significance profile of the *** analysis reveals a positive linear and negative power correlation between fracture network density and branch number to the rock damage resistance,*** damage network model introduces a novel methodology for depicting the interaction of two-dimensional(2D)projected fractures,considering the dynamic spatiotemporal development characteristics and fracture geometric *** helps dynamically characterize properties such as connectivity,permeability,and damage factors while comprehensively assessing damage in rock mass fracture networks.

关键词： Motif Fracture network Topological property Damage resistance Limestone

Unraveling high efficiency multi-step sodium storage and bidirectional redox kinetics synergy mechanism of cobalt-doping vanadium disulfide anode

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Journal of Energy Chemistry 2024年第7期94卷 148-157页

作者： enzhi Li Mingshan wang Yuanlong Feng Lin Yang Qian Li Zhenliang Yang Junchen Chen Bo Yu Bingshu Guo Zhiyuan Ma Yun Huang Jiangtao Liu Xing Li School of New Energy and Materials Southwest Petroleum UniversityChengdu 610500SichuanChina Institute of Materials China Academy of Engineering PhysicsMianyang 621908SichuanChina State Key Laboratory of Advanced Chemical Power Sources Guizhou Meiling Power Sources Co.Ltd.Zunyi 563003GuizhouChina school of Chemistry and Chemical engineering Harbin Institute of TechnologyHarbin 150001HeilongjiangChina

Sodium-based storage devices based on conversion-type metal sulfide anodes have attracted great atten-tion due to their multivalent ion redox reaction ***,they also suffer from sodium polysul-fides(NaPSs)shuttling problems during the sluggish Na^(+) redox process,leading to"voltage failure"and rapid capacity ***,a metal cobalt-doping vanadium disulfide(Co-VS_(2))is proposed to simulta-neously accelerate the electrochemical reaction of VS_(2) and enhance the bidirectional redox of soluble *** is found that the strong adsorption of NaPSs by V-Co alloy nanoparticles formed in situ during the conversion reaction of Co-VS_(2) can effectively inhibit the dissolution and shuttle of NaPSs,and ther-modynamically reduce the formation energy barrier of the reaction path to effectively drive the complete conversion reaction,while the metal transition of Co elements enhances reconversion kinetics to achieve high ***,Co-VS_(2) also produce abundant sulfur vacancies and unsaturated sulfur edge defects,significantly improve ionic/electron diffusion ***,the Co-VS_(2) anode exhibits ultrahigh rate capability(562 mA h g^(-1) at 5 A g^(-1)),high initial coulombic efficiency(~90%)and 12,000 ultralong cycle life with capacity retention of 90%in sodium-ion batteries(SIBs),as well as impressive energy/power density(118 Wh kg^(-1)/31,250 W kg^(-1))and over 10.000 stable cycles in sodium-ion hybrid capacitors(SIHCs).Moreover,the pouch cell-type SIHC displays a high-energy density of 102 Wh kg^(-1) and exceed 600 stable *** work deepens the understanding of the electrochemical reaction mechanism of conversion-type metal sulfide anodes and provides a valuable solution to the shuttlingofNaPSs inSIBsandSIHCs.

关键词： Sodium-ionbatteries Sodium-ion hybrid capacitors Pouch cells Vanadium disulfide Shuttle effect

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Experimental Study on Superficial Sliding of a New Type of Offshore Platform

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China Ocean engineering 1996年第1期11卷 121-128页

作者： wang Zhaojing Zhang Ling Senior Engineer, Geotechnical engineering department, Nanjing hydraulic Research Institute, Nanjing 210024 Engineer, Geotechnical engineering department, Nanjing hydraulic Research Institute, Nanjing 210024 Geotechnical engineering department Nanjing Hydraulic Research Institute Nanjing 210024

In order to verify the theoretical design and computation of a new type of platform, laboratory model test of the superficial sliding of the platform is carried out. Test results show that the requirement for the stability of the platform can be satisfied, and the API-82 criterion can be met. It is also suggested that, in order to enhance the stability of the platform, a buried- pad with porous holes and a long apron-board should be adopted in the design of the new type of platform.

关键词： superficial sliding model test offshore platform

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Experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering boundary effect

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Journal of Rock Mechanics and Geotechnical engineering 2024年第3期16卷 1072-1084页

作者： Xuwei wang Yeshuang Xu State Key Laboratory of Ocean engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China Shanghai Key Laboratory for Digital Maintenance of Buildings and Infrastructure Department of Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China

The boundary condition is a crucial factor affecting the permeability variation due to *** experimental investigation on the permeability of gap-graded soil due to horizontal suffusion considering the boundary effect is conducted,where the hydraulic head difference(DH)varies,and the boundary includes non-loss and soil-loss *** samples are filled into seven soil storerooms connected in *** evaluation,the variation in content of fine sand(ΔR_(f))and the hydraulic conductivity of soils in each storeroom(C_(i))are *** the non-loss test,the soil sample filling area is divided into runoff,transited,and accumulated areas according to the negative or positive ΔR_(f) values.ΔR_(f) increases from negative to positive along the seepage path,and Ci decreases from runoff area to transited area and then rebounds in accumulated *** the soil-loss test,all soil sample filling areas belong to the runoff area,where the gentle-loss,strengthened-loss,and alleviated-loss parts are further divided.ΔR_(f) decreases from the gentle-loss part to the strengthened-loss part and then rebounds in the alleviated-loss part,and C_(i) increases and then decreases along the seepage *** relationship between ΔR_(f) and Ci is different with the boundary *** exponentially decreases with ΔR_(f) in the non-loss test and increases with ΔR_(f) generally in the soil-loss test.

关键词： Suffusion Permeability Experimental investigation Boundary effect Horizontal seepage

Large post-liquefaction deformation of sand:Mechanisms and modeling considering water absorption in shearing and seismic wave conditions

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Underground Space 2024年第5期18卷 3-64页

作者： Jian-Min Zhang Rui wang department of hydraulic engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China

Large deformation of sand due to soil liquefaction is a major cause for seismic *** this study,the mechanisms and modeling of large post-liquefaction deformation of sand considering the significant influence of water absorption in shearing and seismic wave *** of case histories from past earthquakes and review of existing studies highlight the importance of the two *** on the micro and macro scale mechanisms for post-liquefaction shear deformation,the mechanism for water absorption in shearing after initial liquefaction is *** is aided by novel designed constant water-absorption-rate shear *** absorption in shearing can be classified into three types,including partial water absorption,complete water absorption,and compulsory water *** the influence of water absorption in shearing,even a strongly dilative sand under naturally drained conditions could experience instability and large shear *** mechanism for amplification of post-liquefaction deformation under surface wave load is also explained via element tests and theoretical *** shows that surface wave–shear wave coupling can induce asymmetrical force and resistance in sand,resulting in asymmetrical accumulation of deformation,which is amplified by liquefaction.A constitutive model,referred to as CycLiq,is formulated to capture the large deformation of sand considering water absorption in shearing and seismic wave conditions,along with its numerical implementation *** model is comprehensively calibrated based on various types of element tests and validated against centrifuge shaking table tests in the liquefaction experiments and analysis projects(LEAP).The model,along with various numerical analysis methods,is adopted in the successful simulation of water absorption in shearing and Rayleigh wave-shear wave coupling induced large liquefaction ***,the model is applied to high-performance simulation fo

关键词： Liquefaction Sand Large deformation Water absorption in shearing Surface wave Rayleigh wave-shear wave coupling