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Establishing time-dependent model of deformation modulus caused by bedrock excavation rebound by inverse analysis method

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Science china(Technological Sciences) 2008年第S2期51卷 1-7页

作者： WU ZhongRu1,2,GU YanChang1,3,GU ChongShi1,2,GUO HaiQing1 & SU HuaiZhi1,2 1 Hohai University,nanjing 210098,china 2 National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety,nanjing 210098,china 3 nanjing hydraulic research institute,nanjing 210029,china Hohai University Nanjing China National Engineering research Center of Water Resources Efficient Utilization and Engineering Safety Nanjing China nanjing hydraulic research institute Nanjing China

Rock rebound relaxation deformation,or even rock burst,caused by the excavation of dam base and abutment or high rock slope affects their stability and results in the fall of mechanical properties of the *** an inverse analysis method was proposed in this paper to establish the time-dependent model of deformation modulus caused by excavation *** basic principle is based on the combination of observed data of the excavation rebound deformation of dam abutment or rock slope,and the calculated rebound deformation by FEM under ground stress at the corresponding time in the excavation *** norm of the residuals of observed data and calculated data are taken as the objective ***,the time-dependent model of bedrock deformation modulus can be *** method displays its significance in the design of excavation,construction and operation management of dam base and high slope.

关键词： dam base rebound deformation modulus inverse analysis method time-dependent model Xiaowan Hydropower Station

Maximum Entropy Spectral Estimation Based on Accelerating Genetic Algorithm

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Maximum Entropy Spectral Estimation Based on Accelerating Ge...

2009中国控制与决策会议

作者： ZHANG Ming~(1,2),ZHANG Jian-yun~(2,3),JIN Ju-liang~4,WANG Guo-qing~(2,3),HE Rui-min~(2,3) 1.State Key Laboratory of Hydrology-water Resources and hydraulic Engineering,Hohai University,nanjing 210098,china. 2.research Center for Climate Change,MWR,nanjing,210029,china 3.nanjing hydraulic research institute,nanjing 210029,china. 4.School of Civil Engineering,Hefei University of Technology,Hefei 230009,china.

＜正＞The purpose of this paper was to solve the problems of spectral peak shifting and line splitting existing in Burg’s Maximum Entropy Spectral Analysis method（MESA）,to enhance the resolution of entropy spectral,and to increase the adaptability of spectral estimation algorithm to signal length,signal noise ratio and initial phase.A method of accelerating Genetic algorithm based maximum Entropy Spectral estimation method（GES） was proposed,where accelerating genetic algorithm was used to optimize the parameters of MESA and the four equivalent conditions of MESA were used as objective *** typical simulation cases indicated that the phenomenon of spectral peak shifting and line splitting were absent in the frequency spectral estimated by GES,and the ability to discriminate two closed frequency was *** with the traditional MESA methods,GES has good performances in signal processing.

关键词： maximum entropy spectral estimation Burg’s algorithm spectral peak shifting spectral line splitting accelerating genetic algorithm

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燕山水库施工期安全监测资料的统计诊断

水电能源科学 2009年第6期27卷 69-71页

作者：向衍孟桃萍潘奎生南京水利科学研究院江苏南京210029 河南科光工程建设监理有限公司河南郑州450003 河南省水利第一工程局河南郑州450004

针对大坝安全监测资料中常出现偏离目标真值的异常点,基于观测数据质量的有效检测和诊断分析了监测资料误差成因及特点,探讨了监测资料的统计诊断方法,并应用于燕山水库。结果表明,识别异常数据效果良好,可有效提高建模分析精度。

关键词：安全监测误差统计诊断异常值燕山水库

On geo-basis of river regulation——A case study for the middle reaches of the Yangtze River

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Science china(Technological Sciences) 2008年第5期51卷 494-505页

作者： LIU GuoWei nanjing hydraulic research institute, nanjing 210029, china nanjing hydraulic research institute

From the point of view that people have to obey the river's geo-attributes in the river regulation, the definition and the meaning of the geo-attributes of a river are discussed. The geo-basis of the river regulation of the middle reaches of the Yangtze River is expounded in five aspects, including the structural geomorphology environment of flood storage and discharge, the distribution characteristics of subsidence and the sedimentation areas of Dongting Basin, the history evolution of Jianghan Basin, the function of Jianghan Basin and Dongting Basin as the flood water detention areas of Jingjiang River reach in ancient time, and the geological characteristic of Jingjiang River reach. Based on the geo-attributes of the middle reaches of the Yangtze River, some ideas about the middle reach regulation of the Yangtze River are put forward: to process the interchange between the lakes and diked marsh areas in Dongting Basin, to canal the new river route as the flood diversion channel of Jingjiang River reach with the paleo river, to recover the function of Jianghan Basin as flood detention area of the middle reaches. And we should take into consideration the geo-environment of the whole Yangtze River in the river regulation of middle reaches.

关键词： river geo-attributes river regulation the Yangtze River flood

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软弱土层对超长摩擦桩承载性状的影响

水电能源科学 2008年第4期26卷 153-156页

作者：徐闪张齐兴徐志峰江苏省交通厅苏北航务管理处江苏淮安223002 河海大学农业工程学院江苏南京210098 南京水利科学研究院江苏南京210029

以苏通大桥主桥索塔地基中的中粗砾砂土和软粘土为地基土,用三维非线性有限元方法研究了软弱土层的埋深、厚度以及软弱下卧层等对超长摩擦桩承载性状的影响。计算结果表明,超长摩擦桩的承载力随桩周软弱土层的埋深、厚度的增大均呈线性... 详细信息

以苏通大桥主桥索塔地基中的中粗砾砂土和软粘土为地基土,用三维非线性有限元方法研究了软弱土层的埋深、厚度以及软弱下卧层等对超长摩擦桩承载性状的影响。计算结果表明,超长摩擦桩的承载力随桩周软弱土层的埋深、厚度的增大均呈线性减小,随软弱下卧层埋深的增大而增大,桩侧阻力的分布随软弱土层埋深、厚度的变化而变化。

关键词：超长摩擦桩软弱土层承载性状

NUMERICAL SIMULATION OF SCOURING PROCESS UNDER SPILLWAY

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Journal of Hydrodynamics 2001年第4期13卷 55-59页

作者： Yang Jian-ming, Wu Jian-hua nanjing hydraulic research institute, nanjing 210029, china nanjing hydraulic Res. Inst. Nanjing 210029 China

The scour problem under spillway has received a lot of attention in the past decades. For such a complicated problem, most numerical modeling presented only dealt with the water flows in equilibrium scour pools without considering the changing topography of the riverbed. In this paper, the dynamic process is handled with moving grids, and the governing equations are solved using finite volume method with colocated variable arrangement on boundary-fitted non-orthogonal grids. The results show that the given method is efficient, with which the variation of flow parameters, such as mean velocity and mean pressure, etc., can be computed correctly.

关键词： scour pool numerical simulation space conservation law moving grids

CHARACTERISTICS OF FLOW RESISTANCE IN OPEN CHANNELS WITH NON-SUBMERGED RIGID VEGETATION

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Journal of Hydrodynamics 2008年第2期20卷 239-245页

作者： WU Fu-sheng nanjing hydraulic research institute Nanjing 210029 China State Key Laboratory of Hydrology-Water Resources and hydraulic Engineering Nanjing 210029 China

The flow resistance factors of non-submerged rigid vegetation in open channels were analyzed. The formulas of drag coefficient CD and equivalent Manning＇s roughness coefficient na were derived by analyzing the force of the flow of non-submerged rigid vegetation in open channel. The flow characteristics and mechanism of non-submerged rigid vegetation in open channel were studied through flume experiments.

关键词： characteristics of flow resistance non-submerged rigid vegetation drag coefficient equivalent Manning's roughness coefficient

STUDIES ON GREY MODEL DYNAMIC PREDICTION TO CAVITATION DAMAGE OF TURBINES

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Journal of Hydrodynamics 2003年第5期15卷 29-34页

作者： Wu Fu sheng, Tong Zhong shan, Li Yun hui nanjing hydraulic research institute, nanjing 210029, china nanjing hydraulic Res. Inst. Nanjing 210029 China

In thus paper, cavitation damage of turbines is firstly analyzed andpredicated from the view point of system engineering by use of the grey system theory. A detaileddescription of modeling, dynamic prediction and accuracy test for the grey system of turbines wasgiven. Two special cases for grey dynamic prediction as well as its accuracy test were *** results fall into the grade I, the accuracy is satisfactory and its prediction requirements canbe met well. It shows that the grey system theory can be employed to predict the cavitation damageof turbines, and it can provide a scientific basis for timely investigation and maintenance ofturbines.

关键词： turbine cavitation damage grey prediction

STABILITY ANALYSIS OF RIVERBANK SUBJECT TO SEEPAGE

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International Journal of Sediment research 2007年第4期22卷 282-291页

作者： Yan LU1, Yongjun LU2, and Xingnong ZHANG3 1 Postdoctoral Fellow, nanjing hydraulic research institute, State Key Laboratory of Hydrology Water Resources and hydraulic Engineering Science, nanjing, china 210029. 2 Prof., nanjing hydraulic research institute, nanjing, china 210029 3 Prof., nanjing hydraulic research institute, nanjing, china 210029. nanjing Hydraul Res Inst Nanjing 210029 Peoples R China

The stability of riverbanks subject to seepage is studied experimentally and theoretically in this paper. By including seepage in a 3-dimensional theoretical analysis, the study first shows how the critical slope or angle of repose of a cohesionless material is related to the ratio of the hydraulic gradient of seepage to its critical value under the fluidization condition. The critical stable slope is shown to be related to not only the hydraulic gradient but also the seepage direction. Measured laboratory data reasonably fit well with the theoretical relationship for the case of injection and suction. The data reveal that the slope is reduced with injection and increased with suction, respectively. Additionally, the study identifies the seepage direction which results in a minimum critical stable slope for a certain hydraulic gradient of seepage.

关键词： Seepage Riverbank Stability Critical stable slopes Angle of repose Erosion