Clear Water Scour at Rectangular Bridge Pier with Collar

Abstract

Scour is the most significant threat to waterways because it leads to the failure of bridge piers and other structural components. When a collar is put in place around the pier to lessen the direct effect of the downflow on the streambed, the maximum scour depth and velocity rate are reduced. Due to simplicity of a collar implementation around existing bridge piers and the protection of the body of bridge piers. The current paper aimed to test a collar as a flow-altering countermeasure by examining the effect of collars width and elevation on scour reduction around a rectangular pier. The results showed that the collar at higher level of piers have reduced the maximum scour depth by up to 45%, increased the scour hole's volume and planning area is upstream of the pier. Additionally, in order to calculate the maximum scour depth upstream of piers, an empirical formula was created.

Keywords

• scour depth
• bridge pier
• collar
• movable bed
• scour countermeasure