Abstract: The risk analysis simulation model for water resources in the downstream area of Yellow River is established in this paper. The non-synchronous characteristic of the relationship between water consumption and runoff of the Yellow River is considered. the Monte Carlo method is applied to the modeling. The risks of water shortage under the conditions of various scale of water consumption are simulated randomly. The result indicates that the irrigation area should be limited to less than 2,330,000hm2, in case new water resources failed to be developed and the norm of water consumption not being significantly change.
Key words: risk analysis; simulation model; water consumption; water shortage; Yellow River; Mote Carlo method
KOU Xiao-dong,
ZHOU Wei-yuan, YANG Ruo-qiong
(Tsinghua University)
Abstract: In this paper, the theory of 3-D fast Lagrangian analysis and its specialties are introduced. The computation program FLAC-3D developed by Itasca Consulting Group Inc., USA, is applied to the stress-strain analysis of Xiaowan arch dam, 280m in height.
Key words:3-D fast Lagrangian analysis; explicit finite difference method; large deformation; Xiaowan arch dam
LI Zheng-nong1,
LOU Meng-lin2, SONG Jin-zhong2, PANG Jia-bin2
(Wenzhou University;2.Tongji University)
Abstract:The wind pressure distributions and wind load shape coefficients of the rectangular aqueduct with different depth-width ratio are studies in a wind tunnel. Two operation situations of the aqueduct including empty and full depth are considered. The flow field of the wind tunnel is uniform or turbulent flow with intensity 18%. The results show that the measured shape coefficients are significantly different from the traditional design parameters.
Key words:aqueduct; wind pressure; wind tunnel; model test
JIANG Chun-bo1,
ZHANG Qing-hai1, GAO Zhong-xin2
(1.Tsinghua University;2.China Institute of Water Resources and Hydropower Research)
Abstract: A model for predicting the thermal stratified flow and turbidity transportation in the vertical section of a river is established. Since the scheme is explicit for velocity components, pressure and scalar quantities, the model is efficiency and able to simulate long period transportation process of suspending materials in reservoirs and rivers. The model can be used to forecast and control of pollution. The validity of this model is verified by in site observation data.
Key words:thermal stratified flow; vertical 2-D flow model; explicit scheme; pollution control
JIN Ju liang1,
YANG Xiao hua2, JIN Bao ming3,DING Jing1
(Sichuan University;2.Hohai University;3.Water & Electricity Bureau of Nanping)
Abstract: An accelerating genetic algorithm is proposed to solve the complicated nonlinear optimal problem in computation of flow surface profile in open channel. The proposed method helps to minimize the total error arisen in the process of computation.
Key words: Open channel; flow surface profile; computation error; genetic algorithm
LI Jian lin
(University of Hydraulic and Electric Engineering)
Abstract: The strength, deformation and failure criterion of RCC under biaxial compression are studied experimentally. The results are compared with the characteristics of regular concrete.
Key words: RCC; biaxial compression; failure criterion
Abstract: Based on the characteristics of seepage through layered RCCD, a mathematical model coupling the seepage analysis with stress field calculation for RCCD is propsed. The flow through layers in RCCD exerts normal seepage pressure and tangent hauling force on the dam body. The apertures of layers vary with the stress condition. The application of this model to calculation of an example by means of FEM is also given. It is shown that the stress will be higher and the stress concentration at the dam hell will be more notable if the coupling effect is taken into account.
Key words: RCCD；seepage through layer; seepage field; stress field; couple analysis; FEM
DENG Zong cai1,
QIAN Zai zi2
(Shangdong Institute of Building Material;2.Zhejiang University)
Abstract: The fracture parameters and low cycle fatigue fracture properties of carbon fiber reinforced concrete is investigated under static load using three point bending beam test method. The influence of loading history on fracture mechanism is studied by using the method for compliance calibration. The results show that the fracture parameters will be noticeably reduced if the pre loading strength is higher than a certain threshold. While the crack propagation length is independent of the fatigue life. The carbon fiber has a considerable beneficial effect on the behavior of concrete in against fatigue.
Key words: fracture; fatigue; carbon fiber reinforced concrete
LI Feng, YUE
Qian jin
(Dalian University of Technology)
Abstract: According to the simultaneous longitudinal and transverse loading mode, the formulae of ice load and broken length in brittle failure are established for analyzing the interaction between ice ocover and slope structure.Calculation examples are given. It is shown that the ice load tends to lower and the broken length become shorter in this mode. The broken length predicted by the formula is roughly in accordance with the observed data in site.
Key words: simultaneously longitudinal and transverse loading mode; ice load broken length; slope structure
CHEN Jian-sheng,
LI Xin-wen, ZHAO Wei-bin
(Hohai University)
Abstract: In this paper, the mechanism of piping causing concentrated seepage in dyke is studied in depth. In the initial stage of piping, the theory of well flow is applied to imitate the seepage field of river water flowing from piping riser. The affected area of initial piping and its progressively developing process are determined according to the critical sepage gradient. The critical surface of piping can be defined by using the seepage model.At first, the sand rising range and the amount of sands to be flushed out are comparatively larger since the seepage gradient is highest in the vicinity of dyke surface. As piping discharge increased, the seepage gradient will be reduced. As a result, the critical surface draws back inside and a concentrated seepage band formed. The natural and isotope tracer methods for detecting the piping seepage leakage in site are also discussed in this paper.
Key words: piping;seepage gradient; piping critical
WANG Bo，XU Jian-guo
(Zhengzhou University of Technology)
Abstract: In this paper, the dynamic response of large aqueduct to multi-site earthquake input is studied in detail. Shell-beam element model is applied to simulate the aqueduct body and the characteristics of transverse bending-twisting vibration of an open-shell as well as the restraint-twisting deformation are being considered. The formula for computation of dynamic response is esablished The calculation result of a large aqueduct with 10 spans is given as an example.
Key words: large aqueduct; earthquake; dynamic response; multi-site
XU Guo-bin1, REN
Xiao-feng
(Tianjin Investigation Design and Research Institute of Water Resources and Hydropower)
Abstract: The similarity law and the modeling technique for measuring the effect of sediment to lifting force in model test are discussed in this paper. In the model test, the cohesive silt settled in front of the gate is regarded as slurry of Bingham body.
Key words: reservoir sediment; lifting force;similarity law;model test; slurry
WANG Fu-quan1，CAO Shu-you2, LIU
Xing-nian2
(Sichuan Normal College;2.Sichuan University)
Abstract: The stochastic fractal dynamic theory is applied to deduce the distribution of movement characteristic value of suspended pellets. The analysis shows that the characteristic value obeys Levy's stable distribution law。The suitability of the model is verified by using Sumer's experimental data.
Key words: turbulence; bursting; suspended pellet; movement behavior; fractal
GE
Xiao-guang1
(1Hefei University of Technology)
Abstract：A general formula for variable discharge well is deduced.The spline function method is applied.The advantage of this method is illustrated by an example.
Key words：well flow; variable discharge; analytical formula; spline function
WANG Xie-kang,
FANG Duo, CAO Shu-you
(Sichuan University)
Abstract：The neural network principle is applied to establish the feedback network model of bedload transport rate.The feasibility of this model is verified by experimental data.
Key words：bedload transport rate; artificial neural network; coarsened bed material
LIU Tian-yun,
LIU Guang-ting
(Tsinghua University)
Abstract: A new semi-infinite similar element is proposed to model the unbounded far field.The radiation damping is calculated according to the momentum conservation law.A procedure dealing with the soil-structure interaction problem is presented on the basis of the finite element and viscous-spring artificial bounds.The numerical results well agree with the analytical solution。The application of this new model to an example indicates that canyon seismic free field is obviously amplified by the irregular arch abutment.
Key words: artificial boundary condition; seismic wave; arch dam canyon
LIANG Yin-li,
SHAN Lun, KANG Shao-zhong
(Institute of Soil and Water Conservation)
Abstract：Based on the field experimental data in this paper,the crop-water supply strategy for winter wheat and corn in farming land of arid plateau is studied.The results show that,for winter wheat,the water stress sensitivity index in Jensen model during seeding-greening phase reaches the highest value and reaches the second highest value during booting to heading stage.It changes to the third highest value from heading to filling phase.The most important irrigation for crop production is the irrigation before winter and the second important one is during booting and heading phase.The third one is during heading and filling phase.Irrigation in other growth phases is not very important.Optimum irrigation quantity and total water consumption for high drop yield and high water use efficiency are experimentally determined.
Key words：crop-water model; water stress sensitivity index; water supply strategy; winter wheat; spring corn
ZHANG Xiao-ping1,
BAO Cheng-gang2, ZHANG Jing-song3
(Hohai University; 2.Yangtze River Scientific Research Institute; 3.Qingjiang Municipal
Bureau of Construction)
Abstract: The displacement and operation of the dual impervious cores in phase-Ⅱ cofferdam of TGP are analyzed according to the monitoring data.It is concluded that the impervious cores are working safely.The stress and strain are further analyzed by using FEMto forecast the stability of the cores if the material parameters are changed in the future,the water level between two cutoff is variable as well as the upstream level is changed.
Key words：Three Gorges Project; phase-Ⅱ cofferdam; impervious core; cutoff; displacement; monitoring data