Experimental Study of the Effect of Protective Plates Lengths on Reducing the Depth of the Cylindrical Bridge Pier

Subject Areas : Article frome a thesis

Benyamin Daniyari ¹ , Ebrahim Nohani ²

1 - Former M.Sc. Student of Hydraulic Structures, Civil Engineering Department, Islamic Azad University, Dezful Branch, Iran.
2 - Assistant Professor, Department of civil Engineering, Materials and Energy Research Center, Dezful Branch, Islamic Azad University, Dezful, Iran.

Received: 2019-05-18 Accepted : 2021-09-01 Published : 2022-07-23

Keywords: Scour, Protective protection, Laboratory model, Cylindrical bridge pier,

Abstract :

Introduction: Local scouring that occurs due to human construction of structures in the course of rivers flow can lead to erosion of the river's bottom and threatens to change the natural flow of the river. One of the indirect methods of reducing scouring is the use of protective structures.
Methods: In this research, the effect of protective sheet length on the scour depth reduction of cylindrical base was investigated.
Findings: The results of the experiments showed that the laying of protective plates could reduce the scour depth to 69.50%. Also, the best relative length (the length of the protective plate to the width of the bridge base, L / b) of the protective plates is equivalent to one, and with the increase in the length of the protective plates, the effect of the plate length on the scour depth reduction was reversed, so that reducing the scour depth for the relative length of 5.0 and 2 are respectively, 50% and 60% more than the control (without protective plates), and in all experiments, the relative depth of scour has increased with increasing the flow rate.
 

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