The excavated height of the left bank slope of the diversion power system intake in Jinchuan hydropower station is about 16o m. The stability and safety of the slope during construction and its operation/utilization b...The excavated height of the left bank slope of the diversion power system intake in Jinchuan hydropower station is about 16o m. The stability and safety of the slope during construction and its operation/utilization become one of the most important geological engineering problems. At the same time, it is also crucial to select a safe and economic excavation gradient for the construction. We studied the problem of how to select a safe and economic slope ratio by analyzing the geological condition of the high slope, including the lithology, slope structure, structural surface and their combinations, rock weathering and unloading, hydrology, and the natural gradient. The study results showed that the use of an excavation gradient larger than the gradient observed during site investigation and the gradient recommended in standards and field practice manuals is feasible. Then, we used the finite element method and rigid limit equilibrium method to evaluate the stability of the excavation slope under natural, rainstorm and earthquake conditions. The calculated results showed that the excavated slope only has limited failure, but its stability is greatly satisfactory. The research findings can be useful in excavation and slope stabilization projects.展开更多
Cambodia is a country where wetlands cover 30% of the country＇s total area. The Tonle Sap Lake is an important wetland area of Cambodia and Southeast Asia. However, wetland is under threats from infrastructure develo...Cambodia is a country where wetlands cover 30% of the country＇s total area. The Tonle Sap Lake is an important wetland area of Cambodia and Southeast Asia. However, wetland is under threats from infrastructure development, land conversion, water withdrawals, pollution, increased population pressure and hydropower dams building and affect the livelihoods of rural communities. The governance of wetlands is a key action in sustaining the wetland services and the well-being of people. The ＂wise use＂ is a key concept of wetland governance. Although there is considerable research on the ＂wise use＂ and the application of this concept in wetland management, its application in Tonle Sap remains challenged. Hence, this article addresses the question： How wise use is operationalized for the governance of wetlands in Tonle Sap and what implication it has on the wellbeing of peoples and the ecosystem services？ It uses a literature review and a case study to analyze the wetland governance in Tonle Sap, Cambodia. The article describes the wetland governance based on ecosystem services, the direct and indirect driver affecting wetlands and how it threatens the livelihood security of wetland dependent communities. It concludes that the officially wise use of wetlands is a problematic in Tonle Sap.展开更多
基金financially supported by Chinese National Natural Science Foundation (Grant No. 41072229)State Key Laboratory of Hydraulics and Mountain River Engineering (Sichuan University) open fund (Grant No. 201110)Key Laboratory of Hydraulic and Waterway Engineering of the Ministry of Education and National Engineering Research Center for Inland Waterway Regulation (Chongqing Jiaotong University) open fund (Grant No. SLK2011B04)
文摘The excavated height of the left bank slope of the diversion power system intake in Jinchuan hydropower station is about 16o m. The stability and safety of the slope during construction and its operation/utilization become one of the most important geological engineering problems. At the same time, it is also crucial to select a safe and economic excavation gradient for the construction. We studied the problem of how to select a safe and economic slope ratio by analyzing the geological condition of the high slope, including the lithology, slope structure, structural surface and their combinations, rock weathering and unloading, hydrology, and the natural gradient. The study results showed that the use of an excavation gradient larger than the gradient observed during site investigation and the gradient recommended in standards and field practice manuals is feasible. Then, we used the finite element method and rigid limit equilibrium method to evaluate the stability of the excavation slope under natural, rainstorm and earthquake conditions. The calculated results showed that the excavated slope only has limited failure, but its stability is greatly satisfactory. The research findings can be useful in excavation and slope stabilization projects.
文摘Cambodia is a country where wetlands cover 30% of the country＇s total area. The Tonle Sap Lake is an important wetland area of Cambodia and Southeast Asia. However, wetland is under threats from infrastructure development, land conversion, water withdrawals, pollution, increased population pressure and hydropower dams building and affect the livelihoods of rural communities. The governance of wetlands is a key action in sustaining the wetland services and the well-being of people. The ＂wise use＂ is a key concept of wetland governance. Although there is considerable research on the ＂wise use＂ and the application of this concept in wetland management, its application in Tonle Sap remains challenged. Hence, this article addresses the question： How wise use is operationalized for the governance of wetlands in Tonle Sap and what implication it has on the wellbeing of peoples and the ecosystem services？ It uses a literature review and a case study to analyze the wetland governance in Tonle Sap, Cambodia. The article describes the wetland governance based on ecosystem services, the direct and indirect driver affecting wetlands and how it threatens the livelihood security of wetland dependent communities. It concludes that the officially wise use of wetlands is a problematic in Tonle Sap.
