Hamedreza Hajghassem - Master of Civil Engineering (Water and hydraulic structures), Faculty of Engineering, Kharazmi University, Iran, Tehran
Faranak Hashempour - Master Enviroment Engineering, Faculty of Enviroment, Tehran University, Iran, Tehran
Seyed Shahab Emamzadeh - Assistant Professor, Civil Engineering, Kharazmi University, Iran, Tehran
Saeed baay - Bachelor of Science Civil Engineering, Faculty of Engineering Gonbad-e Kavus, golestan, Iran

In this article, first a review of scouring types, scouring formation mechanism and Suggested ways to prevent scouring of bridge by hybrid algorithm. The relative advantages and disadvantages of these methods have been studied in general. Equilibrium local scour depth is reached when the bed-shear stress tends to critical bed-shear stress in the scour hole. Hence, changes to bed-shear stress at the circular bridge pier should be incorporated in the sediment transport theory. This result is suggest shows in the fourth case by widening the river width (up to about ۸۰ meters), upstream of the beginning of wall construction, and its gradual change up to about ۶۰ meters (starting point of the side walls) This jump is transferred to the upstream area of the walling area and its intensity is reduced.

Bridge piers, scouring, scouring depth, soft computing, hybrid algorithm