Ashraf, Ammar
In this study, the dam-break analysis of Ondokuz Mayıs Dam, İhsaniye Dam, and Avcıdere Dam is performed using full momentum HEC-RAS and dynamic wave FLO-2D model. The breach hydrograph for each dam was obtained by modeling the reservoir with dynamic wave routing in HEC-RAS. Three breach hydrographs (S1, S2, and S3) were calculated for each dam using a different set of breach parameters. The breach hydrographs were routed over the floodplain using both HEC-RAS and FLO-2D models. For Ondokuz Mayıs Dam, an accuracy check is performed for elevation data by comparing the Land Registry (Tapu Kadastro) and DSI data, and a new Digital Elevation Model (DEM) is developed using both datasets which is used in flood modeling later. Model calibration is done for Ondokuz Mayıs Dam; by using the flow depth of 2.735 m observed in the Engiz Creek in the year 2010. The calibration was done by varying the roughness values using the trial-and-error method. The calibrated model is then used for the breach hydrograph routing simulations. For Ihsaniye Dam and Avcıdere Dam, roughness values were selected based on the land use Google Earth images. The results of the routing analysis are presented in terms of inundation maps of maximum flow depth, maximum velocity and arrival time of maximum depth. For each dam, comparison of flow depth is presented at selected sections in populated areas. Moreover, the effect of sensitivity of grid resolution, roughness values, and breach hydrograph on the results are also presented. Flood hazard maps are prepared for each breach hydrograph to identify the risk-prone areas in the three dam sites. It was observed that in case of Ondokuz Mayıs Dam breach, Ondokuz Mayıs District will be at high hazard level, for İhsaniye Dam breach, Yalakdere Town will be at a high hazard level, and for Avcıdere Dam breach, Yalakdere town and southern part of Avcıköy town will be at a high hazard level. Flood damages caused by dam breach were also calculated in terms of losses to buildings and agriculture for the relevant areas. From the dam breach modeling results, it was concluded that there is a need to develop emergency action plans for the relevant areas, and the population in the affected areas should be educated about it, so that loss of lives and property can be avoided.


Hydrodynamic Modeling of Dam-Reservoir Response during Earthquakes
Aydın, İsmail (American Society of Civil Engineers (ASCE), 2011-08-03)
A computational model is developed to analyze the hydrodynamic behavior of dam reservoirs during earthquakes. The mathematical model is based on the solution of two-dimensional (2D) Navier-Stokes equations in a vertical, semi-infinite domain truncated by a far-end boundary condition. A depth integrated continuity equation is used to track the deforming free-surface and ensure global mass conservation. A combination of Sommerfeld nonreflecting boundary and dissipation zone methods is implemented at the far e...
Seismic Performance Evaluation of Concrete Gravity Dams by Using Pseudo Dynamic Testing and Simulations
Aldemir, Alper; Binici, Barış (null; 2017-11-24)
Dams are one of the mostimportantinfrastructure components servingfor water storage and energyproduction.Experimental studies on the seismic response of concrete gravity dams are scarce due to the complications regarding thelargescaleof dams and their interaction with the reservoir. This study presents the results of recent novel pseudo-dynamic dam tests (PSD) along with the nonlinear finite element simulations of the specimens. The test specimens were 1/75 scaled version of the highest ...
Analysis Methods for the Investigation of the Seismic Response of Concrete Dams
Aldemir, Alper; Yilmazturk, Sema Melek; Yucel, Ali Riza; Binici, Barış; Arıcı, Yalın; Akman, Altug (2015-01-01)
The consideratiOn of the dam-foundation-reservoir interaction is extremely important for estimating the seismic response of concrete gravity dams. Moreover, nonlinear analysis may be required for determining the possible risk associated with dams. In order to address these issues, DSI recently published the "Guidelines for Seismic Design of Concrete Dams". Authors who have contributed to the preparation of this document provide a perspective on the seismic safety/design of concrete dams and structural analy...
Live load distribution in integral bridge girders
Erhan, S.; Dicleli, Murat (2010-07-15)
In this study, live load distribution formulae for the girders of single-span integral abutment bridges (IABs) are developed. For this purpose, two and three dimensional finite element models (FEMs) of several IABs are built and analyzed. The analyses results are then used to development of live load distribution formulae to estimate the girder live load moments and exterior girder live load shear for IABs with prestressed concrete girders.
Flow dynamics and mixing processes in hydraulic jump arrays: Implications for channel-lobe transition zones
Dorrell, R. M.; Peakall, J.; Sumner, E. J.; Parsons, D. R.; Darby, S. E.; Wynn, R. B.; Ozsoy, E.; Tezcan, Devrim (2016-11-01)
A detailed field investigation of a saline gravity current in the southwest Black Sea has enabled the first complete analysis of three-dimensional flow structure and dynamics of a series of linked hydraulic jumps in,stratified, density-driven, flows. These field observations were collected using an acoustic Doppler current profiler mounted on an autonomous underwater vehicle, and reveal that internal mixing processes in hydraulic jumps, including flow expansion and recirculation, provide a previously unreco...
Citation Formats
A. Ashraf, “NUMERICAL INVESTIGATION OF 2D DAM-BREAK FAILURES BY USING GIS APPLICATIONS,” Ph.D. - Doctoral Program, Middle East Technical University, 2021.