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Wei M.,North China University of Water Conservancy and Electric Power | Lu S.,Shenzhen Government Investment Project Evaluation Center | Zheng Z.,North China University of Water Conservancy and Electric Power
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering

Project of agricultural water conservancy construction is an open and complex system with huge investment, long construction period, complex internal structure and many participants, and which is restrained by time, resources, environment, and so on. The paper aimed to establish a 3-layer structure system of the risks of agricultural water conservancy construction by applying Analytic Hierarchy Process and analyze risks of the construction of a water conservancy project by using Monte Carlo simulation. The results indicate that the main risks of the project are the deformation and leakage of the dam, leakage and penetration objects of the dam foundation. Therefore, for the agricultural water conservancy projects that are mainly used for social and ecological benefits, more strategies should be applied to avoid dam leakage and deformation of engineering so as to reduce the risks of the project. Source

Xiang W.,Harbin Institute of Technology | Zhang A.-J.,Shenzhen Government Investment Project Evaluation Center | Zhang A.-J.,South China University of Technology | Gao W.,Shenzhen Geotechnical Investigation and Surveying Institute
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering

The excavation deformation of deep foundation pits is predicted by 5 kinds of different models. Compared with the test data, the results show that the short-term prediction accuracy of the metabolic GM(1, 1) model, grey Markov chain model and BP model can meet the requirements of the engineering. But their long-term prediction accuracy is unreliable. It is proved that the residual GM(1, 1) model and the grey Markov chain model are suitable for the medium-term and long-term predictions. The excavation deformation control methods for deep foundation pits are summarized. Source

Zhi-Hong Z.,North China University of Water Conservancy and Electric Power | Shi-Bao L.,Shenzhen Government Investment Project Evaluation Center
Lecture Notes in Electrical Engineering

Risk assessment methodologies seek to assess the maximum potential change in the value of a portfolio of financial instruments with a given probability over a pre-set horizon resulting from changes in market factors, credit risk, This paper provides a methodology to assess credit risk. credit transition matrix has a great impact. It will affect the credit rating changes. Credit Change this index ranged from zero when the critical state has a different default status, when the credit quality index greater than zero, the rise in the value of its credit; if the credit quality index is less than zero, the credit quality of the index on the lower Level; If zero, credit rating is to maintain the normal status. © 2012 Springer-Verlag. Source

Zhang A.-J.,South China University of Technology | Zhang A.-J.,Shenzhen Government Investment Project Evaluation Center | Mo H.-H.,South China University of Technology | Zhu Z.-D.,Hohai University
Huanan Ligong Daxue Xuebao/Journal of South China University of Technology (Natural Science)

Large lateral soil movement usually occurs in many unstable slopes due to the excavation or rainfall, which results easily in additional displacement and bending moment in adjacent stabilizing piles. In order to solve this problem, based on the Winkler foundation beam model, the simplified elasto-plastic constitutive relation of the pile-lateral soil is adopted to simulate the nonlinear pile-soil interaction, and a set of four-orders differential governing equations based on the elasto-plastic subgrade reaction method are devised to describe the stabilizing pile-soil slope interaction. Then, the matrix expression of the analytical solutions of the pile response is deduced according to its continuity conditions on the sliding face and boundary conditions at the top and bottom of the pile. Finally, the analytical solutions obtained through the proposed method and the existing measured values in model tests are compared, thus verifying the reliability of the proposed analytical method. Source

Lu S.-B.,Water Resources University | Lu S.-B.,Shenzhen Government Investment Project Evaluation Center | Huang Q.,Water Resources University | Wu C.-G.,Water Resources University | Gao F.,Water Resources University
Journal of Natural Disasters

This paper seeks for a solution to reduce the ice jams hazard in Ningxia-Inner Mongolia reaches of the Yellow River. The reservoir can be used to raise the water level, increase the discharge capacity of drifted ice, reduce the pondage in the river channel, lower the ice peak discharge in river-ice breakup period and avoid a great quantity of ice discharge. The discharge can be reduced via controlling the ice peak discharge and flood discharge. In the meantime, the role of reservoir in controlling the hazard of river ice can be fully exerted via adjusting the flow velocity variation of river reach in winter based on the relation between the hydraulic factors and development of ice condition, so as to relieve the ice hazard. After operation of Liujiaxia Reservoir, the river-ice-breakup day in Shizuishan station with most serious ice hazard is one day earlier than it was before. After operation of Longyanxia Reservoir, the river - ice breakup day in Ningxia-Inner Mongolia reaches is 7 - 10 days earlier than it was before, prevention of ice by reservoir is an effective method. After construction and operation of Liujiaxian Reservoir, the number of ice dam in river-ice breakup period is decreased to 4. 3 from the previous annual average 14 before construction of reservoir, and the ice hazard is reduced obviously. Source

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