SENSITIVITY ANALYSIS OF UNSTEADY FLOW IN HEC-RAS DAM BREAK MODULE

Abstract

The post failure study of dam is generally required to assess the flood magnitude and its behavior in the downstream river portion caused due to failure of dam, so that a preparatory plan can be made to safeguard the lives and properties on the flood plains of the river downstream of the darn. With this aim, a hypothetical darn break analysis for a typical gravity concrete dam in software packages HEC-RAS, dam break module is carried out. in a reach up to 36 Km downstream of dam axis. Present study analyzes the probable outcome of various parameters due to failure of a concrete gravity dam under various failure scenarios. The study focus on flood travel times, flood water velocities, water surface elevation in the downstream of dam. Flood hydrographs are calculated to determine the extent of flooding downstream. The failure of the dam is not analyzed neither structural nor hydraulic-wise but is assumed to be triggered when certain critical criteria are exceeded...