Experimental Investigation of Adding Clay and PAM on Scour Reduction Bridge Piers under the influence Removal of River materials

Scouring damage around bridge piers is consider as foremost detriment and researchers proposed hydraulic or non-hydraulic treatment to solve scouring problems. In this research, a new eco-friendly method has been proposed to reduce not only length and depth of scouring circular bridges but also volume of pits created by removal of river bed materials. Since clay and cationic poly acryl amid (PAM) have good compatibility with the river system and its ecology, the mobile bed sediment was combined with two different grains included %10 clay and %5, %10 PAM injected into clay. Their effects on scouring reduction in four different discharge and three different pit depths were investigated. The results indicate the enhancing effects of adding clay and PAM in reducing the length and depth of scouring. The best performance in the present research is related to the mixture of clay and PAM %10 with scouring depth was %27.24 and %46.78 for grain size 0.6mm and to %26.9 and %45.18 for grain size 0.15mm. The scouring length for both grains decreased by %17.73 and %31.22, respectively. This investigation shows that the utilization of clay and PAM has a positive effect on reducing scouring and its treatment in rivers while being compatible with the ecology of the system, will have an acceptable performance in reducing the depth and scour length.