الفهرس | Only 14 pages are availabe for public view |
Abstract Local scour around bridge piers is an important problem facing the hydraulic engineer, so, this thesis studying local scour around bridge piers. This experimental study was carried out using sample of River Nile soil in hydraulic laboratory of the faculty of engineering, El-Mansoura University- Egypt. Three shapes of pier models were used; rectangular, circular, and triangular nose. These models were made from glasses. Every model shape consists of two sizes; the rectangular pier model have lengths ratio of (L/b = 3 and L/b = 2), the circular pier models have diameter ratio of (D/B = 0.1375 and D/B = 0.1125), and the triangular nose pier models have contraction ratio of (Cr= 0.875 and Cr= 0.900). The scour depths were observed by wireless camera fixed inside the pier model then the horizontal dimensions were observed by hanged camera fixed above the pier model, the data from the observation system was recorded and analysis by PC next to the flume. In this study ninety experiments were performed, three discharges were used on each model, for every discharge there were five water depths. All discharges and water depths were adjusted to make the flow in condition of clear water scour. The collection data used to establish some relationships to study the behavior of scour hole characteristics. from this work, many relationships were obtained, such as the propagation of scour depth with time, the effect of Froude number on the horizontal dimensions of scour hole, the impact of Froude number on the scour depth, and comparison between similar models. |