The reservoir-induced seismicity (RIS) at the Karkheh dam site with a reservoir capacity of about 7.4x109 meters is investigated. Based on the assessment of the seismicity of the dam site in equal time periods before and after reservoir impoundment, it was found that the number of earthquakes have been tripled after impoundment, while their magnitudes and focal depths become smaller. The averag...

The rockfill is modeled as nonlinear elastic material, whose stress-dependent tangent modulus is related to the confining pressure. The parameters of constitutive relationship of stress and strain are determined by tri-dimensional compression test in laboratory. The model applied in this study adopts the technique of element birth and death to simulate the sequential impoundment process of conc...

safety of a dam depends upon not only design and construction but also on the monitoring at the early years after impoundment. shahr- chai dam is located on the shahr- chai river and 12 km away from urmia city in the south- west. the construction of dam was ended in winter 2004, and then both of the dam impoundment and monitoring instrument readings were started, immediately. after ending dam c...

A procedure is presented for simulating the sequential impoundment process of concrete-faced rockfill dam using nonlinear finite element method. The parameters of constitutive relationship of stress and strain are determined by tri-dimensional compression test in laboratory. The model applied in this study adopts the technique of element birth and death to simulate the sequential impoundment pr...

A procedure is presented for simulating thesequential impoundment process of concrete-faced rockfilldam using nonlinear finite element method. The parametersof constitutive relationship of stress and strain aredetermined by tri-dimensional compression test inlaboratory. The model applied in this study adopts thetechnique of element birth and death to simulate thesequ...

Karkheh Dam is the largest dam in Iran with a capacity of about 7.4×109 cubic meters and height of 127 meters. Since the first impoundment, increasing in seismic activity in the dam area has been observed that indicates the possible occurrence of reservoir-induced seismicity (RIS).In the present work, a preliminary evaluation is conducted firstly in order to investigate these observations. Base...

The sediment microbial community in downstream-linked lakes can be affected by the operation of large-scale water conservancy projects. The present study determined Illumina reads (16S rRNA gene amplicons) to analyze and compare the bacterial communities from sediments in Dongting Lake (China) before and after impoundment of the Three Gorges Dam (TGD), the largest hydroelectric project in the w...

The large-scale impoundment of rivers has led to global declines in freshwater mussel populations. It is important to understand the mechanisms underlying these declines to initiate an effective recovery strategy. We examined population traits of three Quadrula species (Quadrula pustulosa, Q. cylindrica and Q. quadrula) at three locations that were exposed to two different reservoir management ...

—We conducted an intensive fish survey in the tailwater reach of a large Ozark river 30 years after its impoundment and compared the recent fish assemblage with those prior to impoundment and shortly (4 years) after impoundment. Our primary objective was to assess whether relatively short-term monitoring following dam construction can adequately quantify the long-term effects of impoundment on ...