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Zhou H.,Xinjiang Uygur Autonomous Region Water Conservancy Management Station | Wang S.,China Institute of Water Resources and Hydropower Research | Wu X.,Xinjiang Hydraulic and Hydropower Research Institute
Shuikexue Jinzhan/Advances in Water Science | Year: 2014

Drip irrigation under mulch is an efficient and water-saving irrigation practice implemented in the arid agricultural areas of China. Based on the micro environments specific to drip irrigation, i. e. “middle of the film”, “between the film”, “edge of the film” and “outside the film”, as well as the 5 960 data collected during 2011-2013 by field contrast test, the relationships between soil level environment, irrigation quota, soil moisture, temperature, evaporation and water-salt movement were established through the Cobb-Douglas model. The results showed that, in arid irrigation areas with strong evaporation and under the combination of plastic film mulching and drip irrigation, soil water and salt migrate horizontally from the “middle of the film” towards the exposed “edge of the film”, and vertically from the lower to the upper soil layers, tending to accumulate in the boundary at the “edge of the film”. The interaction between temperature and evaporation, especially, drives the movement of soil water and salt at mulching spaces and in bare soils. The research further revealed the directional migration of soil water and salt in the context of drip irrigation under mulch, and can provide a basis for the application of water-salt surface discharge method in soils. ©, 2014, China Water Power Press. All right reserved. Source

Su J.,State Key Laboratory of Hydraulics and Mountain River Engineering | Su J.,Key Laboratory of Failure Mechanism and Safety Control Techniques of Earth Rock Dam of the Ministry of Water Resource | Zhou C.,State Key Laboratory of Hydraulics and Mountain River Engineering | Zhou C.,Key Laboratory of Failure Mechanism and Safety Control Techniques of Earth Rock Dam of the Ministry of Water Resource | And 5 more authors.
Yantu Gongcheng Xuebao/Chinese Journal of Geotechnical Engineering | Year: 2015

Most of the widely used check dams are destroyed by huge impact force of debris flows. Flexible gabion arch dam is thus designed. The structure is made of stone gabions and built in the shape of arch with junked tires attached to the upside. Numerical simulation is performed using the software ANSYS LS-DYNA, focusing on the dynamic response of the structure to the impact of the debris flows. The pore pressure and statistic stability of the above two debris retaining structures are analyzed by MIDAS-GTS. The results indicate that the flexible arch structure can effectively reduce the impact force and mud flow pressure through appropriate deformation. ©, 2015, Chinese Society of Civil Engineering. All right reserved. Source

Zhou C.,University of Sichuan | Chen S.-S.,Nanjing Hydraulic Research Institute | He J.-C.,Xinjiang Hydraulic and Hydropower Research Institute | He N.,Nanjing Hydraulic Research Institute | And 2 more authors.
Yantu Lixue/Rock and Soil Mechanics | Year: 2013

It is found from laboratory tests and in-situ observation that earth fills in high dams are usually crushed under high pressure and soaked condition. Particle crushing will change the distribution of earth fills and density; accordingly change the stress-strain behavior. In order to model this behavior, a method is proposed to develop a hypo-plastic constitutive model. Rock particle crushing and density changing, as well as the stress induced anisotropy change in high dams are considered. The hypo-plastic model can also be used to describe cyclic behavior in combination of crushing and density changing effect. The developed model needs test data verification; and then it can be further used into dynamic elastoplastic FEM programming and analysis of high earth-rock dams. Source

Wu Y.,Nanjing Hydraulic Research Institute | Wu Y.,University of Sichuan | Zhou C.,Nanjing Hydraulic Research Institute | Zhou C.,University of Sichuan | And 5 more authors.
Shuili Xuebao/Journal of Hydraulic Engineering | Year: 2014

First, stress analysis of a unit soil slice of the slope was given to calculate the frost heave amount by layering the soil. Secondly, element stress of slope soil was derived from stress equilibrium differential equations under the plane strain condition. The water-drop type yield surface function was modified with the consideration of temperature effect on the preconsolidation pressure of soil. Visco-plasticity model was used between velocity and the visco-plastic strain of the slope soil. The explicit expression of the deformation rate with the depth of slope soil was thus derived. Simulation accuracy was improved by modifying the soil strength and viscosity after freeze-thaw cycles with the depth of slope soil. Finally, numerical example was given in comparison with the field measured data and a good agreement is achieved. ©, 2014, China Water Power Press. All right reserved. Source

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