Effect of cyclic and static coupling on cyclic bearing capacity of soft foundation

LIU Ling, CUI Guangbai, HAO Zhenchun
(1.Hohai University, Jiangsu Nanjing)

LOU Menglin
(Tongji University)

Abstract: Two mathematical models for simulating the opening and closing of contraction joints in normal direction in arch dams are presented in this paper. Applying the modal synthesis technique of free-substructures without directly coupling, the nonlinear equations of motion for seismic response analysis of arch dams is established in the new generalized coordinates spaced by the truncated modes of all monoliths substructures. Furthermore, a new approach, the modal perturbation method, is suggested to calculate approximately the effect of the dynamic pressure on the seismic responses of arch dams. The numerical results of a simple example show that different models of the contraction joints have significant influences on the seismic responses of the arch dams.

HUANG Mingbin, SHAO Mingan, LI Yushan
(Institute of Soil and Water Conservation, CAS & MWR,)

Abstract: A new equation for calculating the transpiration and evaporation by means of Eagleson stochastic dynamic water balance model is presented in this paper. In the model, the influence of limited water supply to the plant is considered and the raining season within a year is divided into 16 periods, according to the characteristics of the rainfall in loess region. The mass conservation equation and a prediction correction algorithm by means of step by step are applied to calculate the partitioning of the water balance factor and the average soil moisture in the 16 periods within a year. All these improvement elevates the calculation accuracy of the model and makes it more useful, especially for water balance modeling of eco hydrological system in the loess plateau.

Key words: stochastic dynamic water balance model; water cycling; loess plateau

A modified stochastic dynamic water balance model and its applicationⅡ。Model validation

HUANG Mingbin,SHAO Mingan, LI Yushan
(Institute of Soil and Water Conservation, CAS & MWR)

WANG Quanjiu, WANG Wenyan, LU Dianqing, SHAO Mingan, LEI Tingwu
(1.Xi'an University of Technology, Institute of Soil and Water Conservation, CAS & MWR,)

WANG Zhirong, WANG Wenyan, WANG Quanjiu, ZHANG Jianfeng
(Xi′an University of Technology)

Abstract: The infiltration experiment of point source irrigation reveals that two kinds of boundary condition may occur, depending on the drip flux. One is non-pond infiltration formed by insufficient flux, whereas another is pond infiltration with moving boundary. The characteristics of these two boundary conditions and the relationships among drip flux, irrigation duration, wetting front and distribution of soil moisture are analyzed in this paper. It concludes that the wetting front rate is one of the important parameters of drip irrigation and the best rate in less than 1.0.

ZHANG Xinli, DING Jing, JIN Juliang
(Institute of Hydraulic Engineering, Sichuan University)

CHANG Anding, GUO Jianqing, WANG Hongsheng
(Xian College of Engineering)

Abstract: The analytical solution describing seepage velocities and draw-downs both in linear and nonlinear flow zone have been derived, in case there is a nonlinear flow zone near the pumping well in the investigated aquifer which is extending infinitely with constant thickness. At the same time the pumping rate is assumed to be constant.

Numerical calculation for two dimensional cavity flow downstream of an aerator

YANG Yongsen, YANG Yongquan
(Tsinghua University; Sichuan University)

Abstract: The boundary integral equations for calculating the 2-D potential cavity flow downstream of the aerator are derived by using Riemann-Hilbert mixed boundary problem technique of analytical function. The numerical scheme for determining the lower free surface is proposed. The calculation result shows that this method is applicable to the complex shaped boundary without special requirement to the initial input value. Comparison between the calculated results and measured data indicates that the adoption of potential flow model is suitable under the condition of low Froude number (Fr<7) when air friction is neglected. Contrarily, the friction force correction must be made if Fr>7 and aeration of free jet is intensified.

HU Xiao, ZHANG Boyan, CHEN Houqun, WANG Ji
(China Institute of Water Resources and Hydropower Research)

Abstract: In this paper, the reasonableness of The Seismic Qualification Guide of Equipment for Nuclear Power Generating Station, HAF J0053 issued by National Nuclear Safe Bureau is discussed based on the experience accumulated in seismic study on key equipment of nuclear power station including the driving mechanism and fuel assembly. The requirements of response spectrum and power spectrum for dynamic characteristic test and aseismic qualification test as well as the requirements of the input performances of the shaking table are discussed in detail It is concluded that the regulations included in the Guide are reasonable and the test conditions required can be satisfied at present in China.

CHEN Yaxin1, SHI Haibin1, TIAN Pude1, LIU Guiyi, ZHANG Jianguo
(Inner Mongolia University of Agriculture,Inner Mongolia Huhot;Bayaner League Institute of Hydraulics)

Study on conditional simulation of soil water-salt spatial variablity monitoring

CHEN Yaxin,SHI Haibin, TIAN Pude,LIU Guiyi,ZHANG Jianguo
(Inner Mongolia University of Agriculture,Inner Mongolia Huhot;Bayaner League Institute of Hydraulics,Inner Mongolia Bayaner)

HE Kaisheng, DAI Jiqun
(Nanjing Hydraulic Research Institute)

Abstract: This paper introduces the displacement observation of 26m thick clay foundation after the adoption of deep wick drain and preloading. The monitoring results of extensometers, inclinometers, piezometer tips and settleplates installed in the base of six 50000m³ oil tanks show that the maximum settlement of the ground is as high as 3.08m and the consolidation reaches 93% after prloading.The engineering practices show that the technology of ultradeep wick drain is feasible in elevating the bearing capacity of deep mucky clay.