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A distributed hydrological model with its application to the Jinghe watershed in the yellow river Basin

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Science china(Technological Sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2.2.& ZHAO Weimin3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, china 2. institute of Environmental Science, Beijing Normal University, Beijing 100875, china 3. Water Resources Conservation Committee of yellow river, zhengzhou 450003, china Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China Beijing Normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm yellow river Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the yellow river Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle yellow river Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, yellow river Basin.

On the variation of water resource structure in the Lower yellow river

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Science china(Technological Sciences) 2004年第z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, LI Tianhong1 & ZHAO Yean2.1. Department of Environmental Engineering, Peking University The Key Laboratory of Water and Sedi- ment Sciences, Ministry of Education, Beijing 100871, china 2. institute of {2. Research, yellow river Conservancy Commission, zhengzhou 450003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China3. Institute of Hydraulic Research YellowRiver Conservancy Commission 450003 Zhengzhou China

In view of river functions and the Minimum Water Demand for river Ecosystem (MWDRE), the water resources in the Lower {2. river is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2.01 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the yellow river, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

The GPS-gravimetry boundary value problem

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Science china Earth Sciences 2005年第3期48卷 398-405页

作者： YU Jinhai1,2.& ZHANG Chuanding2.1. institute of Geodesy and Geophysics of Chinese Academy of Sciences, Wuhan 430077, china 2. {2. Information Engineering University, {2. 450052. china 1. institute of Geodesy and Geophysics of Chinese Academy of Sciences 430077 Wuhan China 2. zhengzhou Information Engineering University 450052 Zhengzhou China

How to determine the earth’s external gravity field with the accuracy of O(T2. by making use of GPS data and gravity values measured on the earth’s surface is dealt with in this paper. There are two main steps: to extend these measured values on the earth’s surface onto the reference ellipsoid at first and then to seek for the integral solution of the external Neumann problem outside the ellipsoid. In addition, the corresponding judging criteria of accuracy to solve the GPS-gravity boundary value problem are established. The integral solution given in the paper not only contains all frequency-spectral information of the gravity field with the accuracy of O(T 2., but is also easily computed. In fact, the solution has great significance for both theory and prac- tice.

关键词： Neumann boundary value problem, integral solution, gravity disturbance.

Risk analysis model for landslide mass of high slope in dam area

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Science china(Technological Sciences) 2008年第S2期51卷 25-31页

作者： GU ChongShi1,2.HE XianFeng3,4,WU ZhongRu1,2.& SU HuaiZhi1,2.1 College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 2.0098,china 2.National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Nanjing 2.0098,china 3 {2. river institute of hydraulic Research,zhengzhou 450003,china 4 Embankment Security Defect Prevention and Control Engineering Research Center of MWR,zhengzhou 450003,china 1. College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing 210098 China 3. yellow river {2. of hydraulic Research Zhengzhou 450003 China 4. Embankment Security Defect Prevention and Control Engineering Research Center of MWR Zhengzhou 450003 China

In order to identify the threat of reservoir bank landslide to dam safety and reduce the risk of dam failure,impact factors of the landslide are *** concept of landslide risk degree is put forward to measure the threat of landslide to dam *** monotony of the landslide risk assessment function which changes with different affecting factors is analyzed *** on gene automatic programming,a data mining model of the landslide risk assessment function is constructed combined with impact factors of reservoir bank landslide on dam *** the assessment function of landslide risk has been excavated and established according to practical project information,which provides a valuable reference for analyzing the impact of landslide on dam risk.

关键词： landslide dam failure risk landslide risk

Efficiency of sediment transport by flood and its control in the Lower yellow river

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Science china(Technological Sciences) 2004年第z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2. LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking University The Key Laboratory of Water and Sedi- ment Sciences, Ministry of Education, Beijing 100871, china 2. General institute of Water Resources and Hydropower Planning and Design, Ministry of Water Re- sources, Beijing 100011, china 3. The yellow river Conservancy Commission, zhengzhou 450003, china 1. Department of Environmental Engineering Peking University 100871 Beijing China 2. The Key Laboratory of Water and Sediment Sciences Ministry of Education 100871 Beijing China 3. General institute of Water Resources and Hydropower Planning and Design Ministry of Water Resources 100011 Beijing China 4. The yellow river Conservancy Commission 450003 Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower yellow river with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower yellow river, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 2. kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower yellow river were also simulated. For the case of sediment concentration being 2. kg/m3, the optimized controlling discharge ranges from 2.90 to 2.00 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower yellow river with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower yellow river, flood, sediment transport, efficiency, simulation, control.

Dynamic Properties of Concrete under Severe Environmental Condition

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 877-882页

作者：闫东明 Department of hydraulic and Environmental Engineering Zhengzhou University Department of Civil and hydraulic Engineering Dalian University of Technology

Exposure to environmental conditions can significantly influence the mechanical behavior of concrete structures in civil engineering. In this study, the effect of environmental factors, such as moisture and temperature, on the strain-rate sensitivity of concrete mixtures was systematically investigated. The strain rate varied from 10^-5s^-1 to 10^-2.^-1. From the investigation it was concluded that moisture content had a significant influence on the strain-rate sensitivity of concrete. With regard to concrete with low moisture content, temperature had little influence on the rate-dependent behavior; while for fully saturated specimens, a significant influence was observed. These phenomena were attributed to the meso-scale bonding properties of the concrete matrix. Equations were derived to characterize the ultimate strength increment of concrete with strain rate under different environmental conditions. An explanation to the dynamic failure mechanisms of concrete based on the experimental findings was proposed.

关键词： concrete strain rate moisture content temperature failure mechanism

Large-eddy simulation of formation of three-dimensional aeolian sand ripples in a turbulent field

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 945-960页

作者： WU ChuiJie1,WANG Ming2.& WANG Liang3 1 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 11602.,china 2.yellow {2. institute of hydraulic Research,zhengzhou 450003,china 3 Research Center for Fluid Dynamics,Science School,PLA University of Science and Technology,Nanjing 2.1101,china State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of Technology Dalian 116024 China yellow river {2. of hydraulic Research Zhengzhou 450003 China Research Center for Fluid Dynamics Science School PLA University of Science and Technology Nanjing 211101 China

With the method of large-eddy simulation,the equation of spherule motion and the method of immersed boundary condition,numerical simulations of three-dimen-sional turbulent aeolian motion and the formation of sand ripples under three-di-mensional turbulent wind and the mutual actions of saltation and creeping motion were carried out. The resulting sand ripples have the form that is flat on the upwind side and steep on the leeward,which is identical to the sand ripples in nature. We also realized the self-restoration process of three-dimensional sand ripples,which shows the correctness of the method of numerical simulation and the models of saltation and creeping. Finally,We analyzed the influence of sand ripples on the three-dimensional turbulent wind field,and found that due to the appearance and development of sand ripples,in the normal direction of ground there exists stronger energy exchange,and moreover,there is close correspondence between the forms of sand ripples and the vorticity close to the ground surface.

关键词： large-eddy simulation equation of spherule motion sand ripples saltation creep

Runoff reduction due to environmental changes in the Sanchuanhe river basin

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International Journal of Sediment Research 2008年第2期23卷 174-180页

Recently,runoff in many river basins in china has been ***,the role that climate change and human activities are playing in this decrease is currently of *** this study,we evaluated an assessment method that was designed to quantitatively separate the effects of climate change and human activities on runoff in river ***,we calibrated the SIMHYD rainfall runoff model using naturally recorded hydro-meteorologic data pertaining to the Sanchuanhe river basin and then determined the effects of climate change and human activities on runoff by comparing the estimated natural runoff that occurred during the period in which humans disturbed the basin to the runoff that occurred during the period prior to disturbance by *** results of this study revealed that the SIMHYD rainfall runoff model performs well for estimating monthly *** addition,we found that absolute runoff reductions have increased in response to human activities and climate change,with average reductions of 70.1% and 2..9% in total runoff being caused by human activities and climate change,*** together,the results of this study indicate that human activities are the primary cause of runoff reduction in the Sanchuanhe river basin.

关键词： Sanchuanhe river Hydrological simulation Climate change Human activities Impact

SIZE DISTRIBUTIONS OF COARSE SAND BED LOAD IN TURBULENT FLOW FIELD

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Journal of Hydrodynamics 1995年第3期7卷 1-6页

作者： Zhang Hong-wu Wang Shan(institute of hydraulic Research {2. river Conservancy Commissivn,zhengzhou 450003,P.R.china)

Putting forth effort on analyzing the action of turbulent flow on the sand particles on rvier bed surface,in this paper, the interdependent relation between the size distribution of coarse sand bed load and flow stren... 详细信息

关键词： coarse sand bed size distributions turbulent flow