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931.
简要介绍了百色水利枢纽水电站引水系统的基本地质条件、工程布置特点,并较为系统地总结了洞室开挖后揭露实际地质情况和开挖支护方法,以及洞室开挖局部出现塌方的具体处理措施. 相似文献
932.
In the last decade many research projects have been developed concerning the breaching of embankment dams. In particular in the framework of the IMPACT Project, results were provided for five large scale field tests and for 22 laboratory tests, so providing the basis for a better comprehension of the breach enlargement process, but also giving useful data for numerical modelling. This paper presents the results of the simulations of some of these tests, where the erosion is triggered by the overtopping of the dam. The simulations were carried out through a physically based model proposed by Macchione. The numerical results confirmed the soundness of the physical basis of the model. 相似文献
933.
Naruhiko Takesada Jagath Manatunge Indika Lakshman Herath 《Lakes & Reservoirs: Research and Management》2008,13(3):245-254
Involuntary resettlement caused by dam construction, especially in developing countries, is being criticized as an additional cause of impoverishment of the poor population being resettled. Despite current improvements in planning and implementation of involuntary resettlement, there is little experience or research on the medium‐ to long‐term consequences of involuntary resettlement on those being resettled. Within the comprehensive water resource development programme in Sri Lanka under the Mahaweli Accelerated Development Programme, Kotmale Dam was constructed in 1985 for the purpose of hydroelectric power generation and irrigation water supply. Construction of the dam caused ≈ 3000 households to be evacuated and relocated. There were two resettlement alternatives for the families being affected by the dam construction project. The first was to stay close to the reservoir, and receive smaller land plots. The other was to settle in newly developed areas for Mahaweli Development Programme, being located >100 km from original villages, but receive larger, irrigated land plots. In order to determine the consequences after 25 years of the resettlement caused by construction of Kotmale Dam, these authors conducted socioeconomic interview surveys of ≈250 households in three resettlement areas, including Mahaweli System H, System B, System C and villages located near the reservoir site. The study results indicated that the majority of the resettlers perceived their livelihoods as being improved after their resettlement. Furthermore, the majority of them expressed their satisfaction regarding their resettlement choices and their current livelihoods, either in the resettlement sites located near the reservoir or in resettlement sites located far from the original settlement sites. However, their satisfaction is usually based on different perceptions on the part of the resettlers that reflect different strategies for coping with involuntary resettlement. The major factors affecting the choices of resettlers were land ownership and/or the educational opportunities for their children. These survey results indicate that the resettled people made conscious choices for their future, especially for their children. For future resettlement programmes, these authors propose that it is important that the considerations of future generations be incorporated in a feasible, sustainable manner, particularly in regard to educational opportunities. 相似文献
934.
水电站大坝安全监测数据的管理 总被引：1，自引：0，他引：1
水电站大坝安全监测的数据是指导大坝施工和运行的科学依据。文章以五强溪水电站左岸库区边坡变形监测的数据为基础,建立了一整套数据管理系统,详尽介绍了系统的功能,特点等,为电站大坝安全监测的数据管理提供了方便。 相似文献
935.
936.
To study the stress, deformation, and seepage pressure during the initial impoundment of the Jinping-I Arch Dam, monitoring analysis and numerical calculation were used in a dam behavior analysis that focused on the working behavior of the dam during the late period of the initial impoundment up to the end of November 2014. The numerical calculation was performed based on feedback analysis of the deformation and stress of the arch dam through inversion of the elastic moduli(E) of the dam body and foundation, using a three-dimensional finite element model for the linear elastic material of the arch dam. The main monitoring indices presented insignificant changes in the late period of the initial impoundment, and the results of feedback analysis were consistent with monitoring results. Analysis results also show that the deformations of the dam body and dam foundation were within the design range; the dam stress distributions were normal, with values lower than the design control criteria; and the seepage flows through the dam body and dam foundation were lower than the design drainage capacity of the deep-well pump house, demonstrating that the Jinping-I Arch Dam was in good working condition, and the initial impoundment had been successfully completed. The results of the working behavior analysis of the Jinping-I hydropower project during the initial impoundment can provide references for safe operation of similar projects. 相似文献
937.
以长江干流向家坝—朱沱河段内局部碍航滩段为研究对象,建立二维非恒定-分形数学模型,统计满足最低维护水深的航道宽度,计算河道横剖面分维数,显示其呈1阶分维特性。河流宽度分维数和水深以及与所在河段、所在断面的形状有很大关系,一般浅滩呈现宽度分维数随水深增大而增大的趋势,横剖面分维数随流速增大整体上呈逐渐减小的趋势。对比同一河段内各滩分维数的大小,在上游流量相同时,河道横断面地形越平顺横剖面分维数越小。 相似文献
938.
Full operation of the Three Gorges Dam (TGD) reduces flood risk of the middle and lower parts of the Yangtze River Basin. However, Dongting Lake, which is located in the Yangtze River Basin, is still at high risk for potentially severe flooding in the future. The effects of the TGD on flood processes were investigated using a hydrodynamic model. The 1998 and 2010 flood events before and after the operation of the TGD, respectively, were analyzed. The numerical results show that the operation of the TGD changes flood processes, including the timing and magnitude of flood peaks in Dongting Lake. The TGD can effectively reduce the flood level in Dongting Lake, which is mainly caused by the flood water from the upper reach of the Yangtze River. This is not the case, however, for floods mainly induced by flood water from four main rivers in the catchment. In view of this, a comprehensive strategy for flood management in Dongting Lake is required. Non-engineering measures, such as warning systems and combined operation of the TGD and other reservoirs in the catchment, as well as traditional engineering measures, should be further improved. Meanwhile, a sustainable philosophy for flood control, including natural flood management and lake restoration, is recommended to reduce the flood risk. 相似文献
939.
Abbas PARSAIE Sadegh DEHDAR-BEHBAHANI Amir Hamzeh HAGHIABI 《Frontiers of Structural and Civil Engineering》2016,10(4):438-444
Numerical modeling of hydraulic phenomenon by computational fluid dynamic (CFD) approaches is one of the main parts in the high cost hydraulic structure studies. In this paper, using Flow 3D as CFD commercial tool, the cavitation phenomenon was assessed along spillway's flip bucket of the Balaroud dam. Performance of numerical modeling was compared to the physical model, which was constructed to this purpose. During numerical modeling, it was found that RNG turbulence model is a suitable performance for modeling the cavitation. Physical modeling shows that minimum cavitation index is about 0.85 and minimum cavitation index based on Flow 3D results is about 0.665, which was related to the flood discharge with return period of 10000 years. The main difference between numerical and physical modeling is related to the head of velocity, which is considered in physical modeling. Results of numerical simulation show that occurrence of cavitation based on cavitation index equal to 0.25 is not possible along the spillway. 相似文献
940.