Document Type : Research Article

Authors

• roozbeh aghamajidi ¹
• amir kamanbedast ²

¹ DINAKANI 20METRI

² civil department

Abstract

In this study, the effect of change of flow discharge on the scouring around the piers of the fifth bridge of Dezful was investigated using the Hsec-RAS numerical model. For this purpose, a hydraulic model was created from the range of the river in which the bridge is located in the software by using field data. Then, by entering the data on the scouring of the bridge bases for the discharge of 25 to 1850 m3/s with different time steps, the effect of change of flow discharge on the scour around the middle and lateral piers of the bridge was investigated. The results of numerical model show a trend The increase was such that in low to moderate discharges (329m3/s) the scouring rate around the middle piers had the highest value, but in high discharges and flood conditions the scurry in the right support had the highest value, also up to 1630 m3/s flood conditions, the scouring rate in the left support had the lowest value, which was due to the morphology of the river bed and the Conditions are the creation of secondary currents in the arc.

Keywords

• Hec-Ras numerical model
• Discharge changes
• Bridge base
• Flood
• Scour

Main Subjects

• مهندسی عمران-سازه های هیدرولیکی