Mountain ecosystem, on the earth, has plenty of natural resources. In Himachal Pradesh all the rivers are snowfed and therefore rich in water resources. These resources have been supporting enough for the generation o...Mountain ecosystem, on the earth, has plenty of natural resources. In Himachal Pradesh all the rivers are snowfed and therefore rich in water resources. These resources have been supporting enough for the generation of electricity through introducing hydropower projects since the last decade However, every developmental activity has its own negative impacts on the surrounding environment. Due to the fragile nature of topography and delicacy of ecology of the Himalaya, it results in lot of disturbances because of high degree of human interferences like construction of major hydropower projects. The increased extent of geological hazards, such as landslides, rock fall and soil erosion, have mainly due to alike developmental interventions in the natural ecosystem. So understanding and analysing such impacts of the hydropower projects have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study, therefore, focuses mainly on the Parbati Stage II (800 MW) and the Parbati Stage III (520 MW) hydropower projects; both of which fall within the Kullu district of Himachal Pradesh. Based on the perception survey of the local communities, the existing land use pattern, status of total acquired land of the residents by hydropower projects, frequent natural hazards and resultant loss to the local communities due to upcoming construction of hydropower projects surrounding to the Parbati Stage II and III have been analysed in the paper. Also, the preventive measures to mitigate these adverse impacts have been suggested to strengthen these projects in eco-friendly manner in the mountain context.展开更多
For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitorin...For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitoring sensors are employed in a majority of engineering projects. These sensors are used to monitor the project during the dam construction and operation periods, and play an important role in reservoir safety operation and producing benefits. With the changing of operating environments and run-time of projects, there are some factors affecting the operation and management of projects, such as a certain amount of damaged sensors and instability of the measured data. Therefore, it is urgent to evaluate existing safety monitoring sensors in water conservancy and hydropower engineering projects. However, there are neither standards nor evaluation guidelines at present. Based on engineering practice, this study examined some key techniques for the evaluation of safety monitoring sensors, including the evaluation process of the safety monitoring system, on-site detection methods of two typical pieces of equipment, the differential resistor sensor and vibrating wire sensor, the on-site detection methods of communication cable faults, and a validity test of the sensor measured data. These key techniques were applied in the Xiaolangdi Water Control Project and Xiaoxi Hydropower Project. The results show that the measured data of a majority of sensors are reliable and reasonable, and can reasonably reflect the structural change behavior in the project operating process, indicating that the availabilities of the safety monitoring sensors of the two projects are high展开更多
In recent years, in Vietnam, economy has been developing rapidly. To ensure rapid and sustainable economic growth, strong support from the energy sector is required. Governments in Vietnam have invested in numerous hy...In recent years, in Vietnam, economy has been developing rapidly. To ensure rapid and sustainable economic growth, strong support from the energy sector is required. Governments in Vietnam have invested in numerous hydropower projects, many of which employ the EPC (Engineering, Procurement and Construction) contract. However, the EPC general contractors are facing many difficulties, resulting in schedule delays and considerable losses. This research is conducted to highlight the main risk factors in the delays of hydropower construction projects in Vietnam. The research employs the method of statistical calculations and risk analysis to obtain feedback from experts participating in similar projects. The research outcomes are as follows: identifying the risks that can cause delays in EPC hydroelectric construction projects in Vietnam;calculating and classifying the degree of impact of each risk to the progress of the construction. The practical significance of this study is to ensure the timely completion of projects, benefits for the investors, and the EPC general contractors.展开更多
With the rapid expansion of hydropower projects, Construction safety problem has become one of the bottlenecks for the development of hydropower industry. Combined with the construction of the diversion channel projec...With the rapid expansion of hydropower projects, Construction safety problem has become one of the bottlenecks for the development of hydropower industry. Combined with the construction of the diversion channel project of Guan Yinyan hydropower station, from the point of view of construction traffic safety, based on the result of the FAHP model, factors which influence the construction safety of the diversion channel project of Guan Yinyan hydropower station have been found, relative measures focuses on the approach to eliminate hazards and guarantee construction safety have been elaborated.展开更多
The construction of water conservancy projects should commence during optimal atmospheric conditions and non-flood period to ensure completion before the flood season begin in summer.In most areas of Northern China,th...The construction of water conservancy projects should commence during optimal atmospheric conditions and non-flood period to ensure completion before the flood season begin in summer.In most areas of Northern China,the temperature during winter remain at lower level,in which environmental factors play the most important role in the construction of water conservancy projects.In particular,low temperature directly affects the strength of concrete and delays its solidification,this highly affects the quality and progress of concrete construction.In order to overcome this barrier,better planning,for reasonable and effective construction techniques and targeted control measures should be adopted to reduce the adverse effects of low temperature to assure a strong and safe architecture.展开更多
The Three-River Headwater Region(TRHR)of China is a typical representative of the alpine environment in the Central Asian plateau and the alpine grassland in the world.Grassland degradation is one of its serious eco-l...The Three-River Headwater Region(TRHR)of China is a typical representative of the alpine environment in the Central Asian plateau and the alpine grassland in the world.Grassland degradation is one of its serious eco-logical problems.The purpose of this study is to quantify the joint impacts of climate and human activities on grassland changes in TRHR after two phases of Ecological Conservation and Construction Project(Ecological Project).Grassland vegetation coverage is selected as an indicator for analyzing grassland changes.We adopt Sen+Mann-Kendall trend analysis,residual trend analysis and correlation analysis methods to analyze the trends in spatial-temporal changes and driving factors of grassland in TRHR from 2000 to 2019.The results show that:(1)The grassland has been mainly restored,and the degraded grassland area only accounts for 1.66%of TRHR.After the implementation of the first phase of the Ecological Project,the percentage of restored grassland area has significantly increased from 8.82%to 24.57%,and slightly decreased during the second phase.(2)The establish-ment of national nature reserves and the implementation of the Ecological Project have changed the situation that“the grassland inside the reserve is worse than that outside the reserve”.(3)Grassland restoration is mainly af-fected by the joint effects of climate and human activities.Nevertheless,grassland degradation is mainly affected by human activities such as overgrazing and grassland reclamation.All of these findings can enrich our under-standing of grassland restoration in TRHR.Artificial measures have certain limitations in promoting grassland restoration.Natural restoration should be considered when human beings strengthen ecological conservation and transform their production and life styles.展开更多
Hydrological data on the Upper Qingjiang River from 1960 to 2012 document trends of runoff caused by hydropower engineering projects and long-term changes in rainfall. Annual runoff correlates strongly with annual pre...Hydrological data on the Upper Qingjiang River from 1960 to 2012 document trends of runoff caused by hydropower engineering projects and long-term changes in rainfall. Annual runoff correlates strongly with annual precipitation, but is significantly reduced after reservoir construction compared to earlier values. Comparisons of intense, pre- and post-construction rainfall events suggest that the Chebahe and Dalongtan reservoir projects respectively clips the magnitude of the flood peaks and delays runoff delivery.展开更多
文摘Mountain ecosystem, on the earth, has plenty of natural resources. In Himachal Pradesh all the rivers are snowfed and therefore rich in water resources. These resources have been supporting enough for the generation of electricity through introducing hydropower projects since the last decade However, every developmental activity has its own negative impacts on the surrounding environment. Due to the fragile nature of topography and delicacy of ecology of the Himalaya, it results in lot of disturbances because of high degree of human interferences like construction of major hydropower projects. The increased extent of geological hazards, such as landslides, rock fall and soil erosion, have mainly due to alike developmental interventions in the natural ecosystem. So understanding and analysing such impacts of the hydropower projects have mainly been on the environment in various forms but natural hazards have been frequent ones. The present study, therefore, focuses mainly on the Parbati Stage II (800 MW) and the Parbati Stage III (520 MW) hydropower projects; both of which fall within the Kullu district of Himachal Pradesh. Based on the perception survey of the local communities, the existing land use pattern, status of total acquired land of the residents by hydropower projects, frequent natural hazards and resultant loss to the local communities due to upcoming construction of hydropower projects surrounding to the Parbati Stage II and III have been analysed in the paper. Also, the preventive measures to mitigate these adverse impacts have been suggested to strengthen these projects in eco-friendly manner in the mountain context.
基金supported by the National Natural Science Foundation of China(Grants No.51179108and50909066)the Key Research Foundation of Nanjing Hydraulic Research Institute(Grant No.Y711007)
文摘For the evaluation of construction quality and the verification of the design of water conservancy and hydropower engineering projects, and especially for the control of dam safety operation behavior, safety monitoring sensors are employed in a majority of engineering projects. These sensors are used to monitor the project during the dam construction and operation periods, and play an important role in reservoir safety operation and producing benefits. With the changing of operating environments and run-time of projects, there are some factors affecting the operation and management of projects, such as a certain amount of damaged sensors and instability of the measured data. Therefore, it is urgent to evaluate existing safety monitoring sensors in water conservancy and hydropower engineering projects. However, there are neither standards nor evaluation guidelines at present. Based on engineering practice, this study examined some key techniques for the evaluation of safety monitoring sensors, including the evaluation process of the safety monitoring system, on-site detection methods of two typical pieces of equipment, the differential resistor sensor and vibrating wire sensor, the on-site detection methods of communication cable faults, and a validity test of the sensor measured data. These key techniques were applied in the Xiaolangdi Water Control Project and Xiaoxi Hydropower Project. The results show that the measured data of a majority of sensors are reliable and reasonable, and can reasonably reflect the structural change behavior in the project operating process, indicating that the availabilities of the safety monitoring sensors of the two projects are high
文摘In recent years, in Vietnam, economy has been developing rapidly. To ensure rapid and sustainable economic growth, strong support from the energy sector is required. Governments in Vietnam have invested in numerous hydropower projects, many of which employ the EPC (Engineering, Procurement and Construction) contract. However, the EPC general contractors are facing many difficulties, resulting in schedule delays and considerable losses. This research is conducted to highlight the main risk factors in the delays of hydropower construction projects in Vietnam. The research employs the method of statistical calculations and risk analysis to obtain feedback from experts participating in similar projects. The research outcomes are as follows: identifying the risks that can cause delays in EPC hydroelectric construction projects in Vietnam;calculating and classifying the degree of impact of each risk to the progress of the construction. The practical significance of this study is to ensure the timely completion of projects, benefits for the investors, and the EPC general contractors.
文摘With the rapid expansion of hydropower projects, Construction safety problem has become one of the bottlenecks for the development of hydropower industry. Combined with the construction of the diversion channel project of Guan Yinyan hydropower station, from the point of view of construction traffic safety, based on the result of the FAHP model, factors which influence the construction safety of the diversion channel project of Guan Yinyan hydropower station have been found, relative measures focuses on the approach to eliminate hazards and guarantee construction safety have been elaborated.
文摘The construction of water conservancy projects should commence during optimal atmospheric conditions and non-flood period to ensure completion before the flood season begin in summer.In most areas of Northern China,the temperature during winter remain at lower level,in which environmental factors play the most important role in the construction of water conservancy projects.In particular,low temperature directly affects the strength of concrete and delays its solidification,this highly affects the quality and progress of concrete construction.In order to overcome this barrier,better planning,for reasonable and effective construction techniques and targeted control measures should be adopted to reduce the adverse effects of low temperature to assure a strong and safe architecture.
基金This research is jointly funded by Key Technologies Research and De-velopment Program of China(Grant No.2017YFC0404503)funding project for basic scientific research operations of China’s Central Public Welfare Scientific Research Institutes(AR2117).
文摘The Three-River Headwater Region(TRHR)of China is a typical representative of the alpine environment in the Central Asian plateau and the alpine grassland in the world.Grassland degradation is one of its serious eco-logical problems.The purpose of this study is to quantify the joint impacts of climate and human activities on grassland changes in TRHR after two phases of Ecological Conservation and Construction Project(Ecological Project).Grassland vegetation coverage is selected as an indicator for analyzing grassland changes.We adopt Sen+Mann-Kendall trend analysis,residual trend analysis and correlation analysis methods to analyze the trends in spatial-temporal changes and driving factors of grassland in TRHR from 2000 to 2019.The results show that:(1)The grassland has been mainly restored,and the degraded grassland area only accounts for 1.66%of TRHR.After the implementation of the first phase of the Ecological Project,the percentage of restored grassland area has significantly increased from 8.82%to 24.57%,and slightly decreased during the second phase.(2)The establish-ment of national nature reserves and the implementation of the Ecological Project have changed the situation that“the grassland inside the reserve is worse than that outside the reserve”.(3)Grassland restoration is mainly af-fected by the joint effects of climate and human activities.Nevertheless,grassland degradation is mainly affected by human activities such as overgrazing and grassland reclamation.All of these findings can enrich our under-standing of grassland restoration in TRHR.Artificial measures have certain limitations in promoting grassland restoration.Natural restoration should be considered when human beings strengthen ecological conservation and transform their production and life styles.
基金supported by the National Natural Science Foundation of China (No. 31460132)the Scientific Research Project of Hubei Provincial Department of Education (No. Q20122901)
文摘Hydrological data on the Upper Qingjiang River from 1960 to 2012 document trends of runoff caused by hydropower engineering projects and long-term changes in rainfall. Annual runoff correlates strongly with annual precipitation, but is significantly reduced after reservoir construction compared to earlier values. Comparisons of intense, pre- and post-construction rainfall events suggest that the Chebahe and Dalongtan reservoir projects respectively clips the magnitude of the flood peaks and delays runoff delivery.