Experimental Study on Riprap Extension around Wing-wall Abutments

Articles in Press

Document Type : Research Article

Authors

Department of Civil and Environmental Engineering, Amirkabir University of Technology, Tehran, Iran.

10.24200/sci.2026.66607.10140

Abstract

Various equations are proposed for stable design of riprap stones in different abutment shapes. However, extension of the riprap layer at wing-wall abutments and its launching action is not properly studied. In the present paper, the necessary dimensions of the riprap layer around bridge wing-wall abutments placed in flood plain was studied experimentally. To reduce the volume of required stones, the launching action of the riprap layer was also investigated with accepting 10% loss of the riprap area due to some scouring downstream of the riprap layer. It was postulated that limited scouring downstream of the riprap if does not develop at its sides is acceptable. An empirical equation was also developed for the depth and location of the maximum scour hole downstream of the riprap layer. Experimental results indicated that flow intensity and the riprap extension’s length and width caused the most pronounced effects on the pattern of scouring downstream of the riprap layer. Moreover, the results showed that changing riprap thickness from 3D50 to 5D50 where D50 is average size of riprap stones had no significant effect on the scour depth in the range of variables tested.

Keywords

Main Subjects

Scientia Iranica

Articles in Press, Accepted Manuscript
Available Online from 24 July 2026

Files

History

  • Receive Date: 23 March 2025
  • Revise Date: 04 February 2026
  • Accept Date: 12 May 2026

Share

How to cite

Statistics