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COUPLING EFFECT BETWEEN RELIABILITY OF BEDDING LAYER AND STABILITY OF DOWNSTREAM CONCRETE SLAB OF OVERFLOW EARTH-ROCK COFFERDAM

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Journal of Hydrodynamics 2007年第5期19卷 613-622页

作者： HU Zhi-gen FAN Xi-e HUAI Wen-xin LIU quan ZHU Ming-xing State Key Laboratory of Water Resource and Hydropower Engineering Science Wuhan University Wuhan 430072 China China Gezhouba （Group） Corporation Yichang 443002 China

The protection of downstream concrete slab is a key issue for the stability of overflow earth-rock cofferdam. The coupling effect between bedding layer and concrete slab was taken into account when the stability of downstream concrete slab was researched. The characteristics of overflow and seepage over the downstream concrete slab were investigated when floodwater passes over the cofferdam. Firstly a limit equation of seepage failure for the bedding layer was derived with the consideration of geometric and mechanical factors, and a reliability model was established and numerically simulated. Then based on the reliability calculation for the bedding layer, the coupling effect between bedding layer and downstream concrete slab was analyzed. Under the most unfavorable pressure condition for the concrete slab, its instability criterion was put forward, which offers a structural design tool of downstream concrete slab for overflow earth-rock cofferdam. Compared with model tests, it shows that the model of reliability calculation of bedding layer and the stability analysis of downstream concrete slab are effective.

关键词： overflow earth-rock cofferdam couplingeffect reliability calculation stability analysis Monte Carlomethod

Self-Sustaining of Critical Park Microgrids Integrating Mobile Emergency Generators Subjective to Major Outage

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1441-1453页

作者： quan Sui Lei Zhang School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou 450001China School of Electrical and New Energy Three Gorges UniversityYichang 443002China

In the event of a major power outage,critical park microgrids(PMGs)could be self-sustaining if mobile emergency generators(MEGs)are stationed to share ***,the need for privacy protection and the value of flexible power support on minute-time scales have not been given enough *** address the problem,this paper proposes a new self-sustaining strategy for critical PMGs integrating ***,to promote the cooperation between PMG and MEG,a bi-level benefit distribution mechanism is designed,where the participants'multiple roles and contributions are identified,and good behaviors are also ***,to increase the alliance benefits,three loss coordination modes are presented to guide the power exchange at the minute level between the MEG and PMG,considering the volatility of renewable generation and *** this basis,a multi-time scale power-energy scheduling strategy is formulated via the alternating direction method of multipliers(ADMM)to coordinate the PMG and ***,a dimensionality reduction technology is designed to equivalently simplify the optimization problem to facilitate the adaptive-step-based ADMM *** studies indicate that the proposed strategy achieves the self-sustaining of PMGs integrating MEGs while increasing the economy by no less than 3.1%.

关键词： Distributed optimization loss coordination mode mobile emergency generator park microgrid power-energy self-sustaining privacy protection

Numerical simulation of two droplets impacting upon a dynamic liquid film

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Chinese Physics B 2022年第4期31卷 562-573页

作者： quan-Yuan Zeng Xiao-Hua Zhang Dao-Bin Ji Three Gorges Mathematical Research Center China Three Gorges UniversityYichang 443002China College of Science China Three Gorges UniversityYichang 443002China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002China

The impact of droplets on the liquid film is widely involved in industrial and agricultural *** recent years,plenty of works are limited to dry walls or stationary liquid films,and the research of multi-droplet impact dynamic films is not *** on this,this paper employs a coupled level set and volume of fluid(CLSVOF) method to numerically simulate two-droplet impingement on a dynamic liquid *** our work,the dynamic film thickness,horizontal central distance between the droplets,droplets’ initial impact speed,and simultaneously the flow velocity of the moving film are *** evolution phenomenon and mechanism caused by the collision are analyzed in *** find that within a certain period of time,the droplet spacing does not affect the peripheral crown height;when the droplet spacing decreases or the initial impact velocity increases,the height of the peripheral crown increases at the beginning,and then,because the crown splashed under Rayleigh-Plateau instability,this results in the reduction of the crown *** the same time,it is found that when the initial impact velocity increases,the angle between the upstream peripheral jet and the dynamic film becomes *** more obvious the horizontal movement characteristics,the more restrained the crown height;the spread length increases with the increase of the dynamic film speed,droplet spacing and the initial impact *** the liquid film is thicker,more fluid enters the crown,due to the crown being unstable,the surface tension is not enough to overcome the weight of the rim at the end of the crown,resulting in droplets falling off.

关键词： two droplets moving liquid film CLSVOF mechanism analysis

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爆破振动对邻近水工建筑物影响的监测与分析

人民长江 2015年第10期46卷 83-86页

作者：钟权李家亮王义昌中国电建集团成都勘测设计研究院有限公司四川成都610072 武汉大学水资源与水电工程科学国家重点实验室湖北武汉430072

在邻近水工建筑物环境下进行爆破开挖,爆破振动会产生一些负面效应,因此爆破振动监测十分必要。以大渡河深溪沟水电站安装间排水灌浆廊道开挖工程为例,对厂房机组及其他关键部位进行了爆破振动监测,并对数据进行回归分析,通过调整和优... 详细信息

在邻近水工建筑物环境下进行爆破开挖,爆破振动会产生一些负面效应,因此爆破振动监测十分必要。以大渡河深溪沟水电站安装间排水灌浆廊道开挖工程为例,对厂房机组及其他关键部位进行了爆破振动监测,并对数据进行回归分析,通过调整和优化爆破参数,既确保了原有机组的正常运行和其他水工建筑物的安全,同时又加快了工程施工进度,可为类似工程提供借鉴和参考。

关键词：爆破振动安全监测参数优化水工建筑物

Energy conversion and deposition behaviour in gravitational collapse of granular columns

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Journal of Mountain Science 2020年第1期17卷 216-229页

作者： HUANG Bo-lin WANG Jian ZHANG quan LUO Chao-lin CHEN Xiao-ting Hubei Key Laboratory of Disaster Prevention and Mitigation China Three Gorges UniversityYichang 443002China National Observatory of the Three Gorges Landslide Yangtze RiverHubei ProvinceChina Three Gorges UniversityYichang 443002China Pearl River Water Resources Research Institute Pearl River Water Resources Research InstituteGuangzhou 510611China

The high-density gravitational collapse of granular columns is very similar to the movements of large collapsing columns in nature. Based on the development of dangerous columnar rock mass in fields, granular column collapse boundary condition in the physical experiments of this study is a new type of boundary conditions with a single free face and a three-dimensional deposit. Physical experiments have shown that the mobility of small particles during the collapse of granular columns was greater than that of large particles. For example, when particle size was increased from 5 to 15 mm, deposit runout was decreased by about 16.4%. When a column consisted of two particle types with different sizes, these particles could mix in the vicinity of layer interfaces and small particles might increase the mobility of large particles. In the process of collapse, potential and kinetic energy conversion rate is fluctuated. By increasing initial aspect ratio a, the ratio of the initial height of column to its length along flow direction,potential and kinetic energy conversion rate is decreased. For example, as a was increased from 0.5 to 4, the ratio of maximum kinetic energy obtained and total potential energy loss was decreased from47.6% to 7.4%. After movement stopped, an almost trapezoidal body remained in the column and a fanlike or fan-shaped accumulation was formed on the periphery of column. Using multiple exponential functions of the aspect ratio a, the planar morphology of the collapse deposit of granular columns could be quantitatively characterized. The movement of pillar dangerous rock masses with collapse failure mode could be evaluated using this granular column experimental results.

关键词： Granular columns Rock collapse Collapse experiments Energy conversion Deposit sequence Deposit prediction

Diurnal variations of the planetary boundary layer height estimated from intensive radiosonde observations over yichang, China

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Science China(Technological Sciences) 2014年第11期57卷 2172-2176页

作者： ZHANG YeHui ZHANG ShaoDong HUANG ChunMing HUANG KaiMing GONG Yun GAN quan Applied Hydrometeorological Research Institute Nanjing University of Information Science & Technology State Key Laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University School of Electronic Information Wuhan University

By using the eight-times-daily sampling data from an intensive radiosonde observation campaign at yichang(111°18′E,30°42′N),China in August 2006 and January 2007,the diurnal variation of the planetary boundary layer height determined by using a bulk Richardson(Ri)number approach,was studied in this *** was found that the boundary layer heights in both summer and winter months showed diurnal changes and the daily cycle was deeper in summer,which agreed well with the previous studies;the monthly averaged height was 103–1112 m and 89–450 m in summer and winter,respectively;the morning rise began at 0700 LT/1000 LT in summer/winter and the evening transition occurred at 1900 LT in both seasons;the maximum height occurred in the afternoon for most cases,except some peaks found in the winter night;the surface temperature and relative humidity dominated the variations of summer height,while the diurnal variation shown in January 2007 might have some connections with the dynamical processes in the lower troposphere,besides the surface effects.

关键词： planetary boundary layer height bulk Richardson (Ri) number method intensive radiosonde observations diurnalvariation

Channelized and unchannelized collapses of granular columns on a horizontal surface

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Journal of Mountain Science 2020年第12期17卷 2982-2996页

作者： ZHANG quan HUANG Bo-lin ZHAO Hai-lin CHEN Xiao-ting LUO Chao-lin Hubei Key Laboratory of Disaster Prevention and Mitigation China Three Gorges UniversityYichang 443002China Pearl River Water Resources Research Institute Pearl River Water Resources Research InstituteGuangzhou 510611China

Columnar dangerous rock mass is widely developed in many high and steep mountain areas around the *** often collapses,disintegrates and produces debris flow,which is *** collapse process of the columnar dangerous rock mass is very similar to the collapse of granular *** this paper,we report the results of an experimental investigation of the flow induced by the collapse of a column of granular material over a horizontal *** different setups are used,namely,a channelized granular column collapse(i.e.,two-dimensional) and an unchannelized granular column collapse(i.e.,three-dimensional),allowing us to compare channelized and unchannelized collapses *** experimental data suggest that our experimental findings were markedly different from those reported by previous authors(i.e.,include the channelized and unchannelized collapse flows showed differences in energy conversion and dissipation).In channelized collapse flows,the maximum vertical speed appears in the free fall regime,while,the maximum speed in the vertical direction of unchannelized collapse flows appears in the spreading *** the whole collapse process,i.e.,in channelized and unchannelized collapse flows,the conversion of potential energy and kinetic energy does not occur uniformly,and the maximum kinetic energy of the channelized collapse flows is higher than that of the unchannelized collapse flows,and compared with the unchannelized collapse flows,the dissipation energy in the channelized collapse flows is lower.A series of experiments was performed to predict the behaviour of different granular columns(characterized by different initial aspect ratio(a),varying from 1 to 4).The data obtained from 2 D experimental model and3 D experimental model have certain amount of difference,such as the particle runout distance(d1),the maximum central height(h2),and the deposition angle(i.e.,β1,β2).These differences show that the 2 D experimental model does not fully represen

关键词： Granular column Unchannelized collapses flows Energy conversion Energy dissipation Deposition prediction Gravity height Deposition angle

Structural plane recognition from three-dimensional laser scanning points using an improved region-growing algorithm based on the robust randomized Hough transform

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Journal of Mountain Science 2023年第11期20卷 3376-3391页

作者： XU Zhi-hua GUO Ge SUN Qian-cheng WANG quan ZHANG Guo-dong YE Run-qing Key Laboratory of Geological Hazards on Three Gorges Reservoir Area Ministry of EducationYichang 443002China National Field Observation and Research Station of Landslides in Three Gorges Reservoir Area of Yangtze River Yichang443002China Wuhan Center China Geological Survey(Geosciences Innovation Center of Central South China)Wuhan 430205China

The staggered distribution of joints and fissures in space constitutes the weak part of any rock *** identification of rock mass structural planes and the extraction of characteristic parameters are the basis of rock-mass integrity evaluation,which is very important for analysis of slope *** laser scanning technique can be used to acquire the coordinate information pertaining to each point of the structural plane,but large amount of point cloud data,uneven density distribution,and noise point interference make the identification efficiency and accuracy of different types of structural planes limited by point cloud data analysis technology.A new point cloud identification and segmentation algorithm for rock mass structural surfaces is *** on the distribution states of the original point cloud in different neighborhoods in space,the point clouds are characterized by multi-dimensional eigenvalues and calculated by the robust randomized Hough transform(RRHT).The normal vector difference and the final eigenvalue are proposed for characteristic distinction,and the identification of rock mass structural surfaces is completed through regional growth,which strengthens the difference expression of point *** addition,nearest Voxel downsampling is also introduced in the RRHT calculation,which further reduces the number of sources of neighborhood noises,thereby improving the accuracy and stability of the *** advantages of the method have been verified by laboratory *** results showed that the proposed method can better achieve the segmentation and statistics of structural planes with interfaces and sharp *** method works well in the identification of joints,fissures,and other structural planes on Mangshezhai slope in the Three Gorges Reservoir area,*** can provide a stable and effective technique for the identification and segmentation of rock mass structural planes,which is beneficial in engineering practice.

关键词： 3D laser scanning Rock discontinuity structural plane Intelligent recognition Robust randomized Hough transform Improved region growing algorithm

Shuffled complex evolution coupled with stochastic ranking for reservoir scheduling problems

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Water Science and Engineering 2019年第4期12卷 307-318页

作者： Jing-qiao Mao Ming-ming Tian Teng-fei Hu Kang Ji Ling-quan Dai Hui-chao Dai College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210098China Ningbo Hongtai Water Conservancy Information Technology Co. Ltd.Ningbo 315040China College of Hydraulic and Environmental Engineering Three Gorges UniversityYichang 443002China

This paper introduces an optimization method(SCE-SR)that combines shuffled complex evolution(SCE)and stochastic ranking(SR)to solve constrained reservoir scheduling problems,ranking individuals with both objectives and constrains considered.A specialized strategy is used in the evolution process to ensure that the optimal results are feasible *** method is suitable for handling multiple conflicting constraints,and is easy to implement,requiring little parameter *** search properties of the method are ensured through the combination of deterministic and probabilistic *** proposed SCE-SR was tested against hydropower scheduling problems of a single reservoir and a multi-reservoir system,and its performance is compared with that of two classical methods(the dynamic programming and genetic algorithm).The results show that the SCE-SR method is an effective and efficient method for optimizing hydropower generation and locating feasible regions quickly,with sufficient global convergence properties and *** operation schedules obtained satisfy the basic scheduling requirements of reservoirs.

关键词： Reservoir scheduling Optimization method Constraint handling Shuffled complex evolution Stochastic ranking