Experimental Investigation on the Effectiveness of Nanosilica for Reducing Local Scour Around Cylindrical Bridge Piers.

Local scour is one the leading factors contributing to bridge failures. This phenomenon can be defined as the consequences of the erosion force of the flow of the sediments in the region surrounding the bridge's piers. In this study, an experimental investigation was conducted to develop an innovative method for protecting the bed and reducing the susceptibility of the non-uniform sand bed to erosion by utilizing nanosilica powder. Four nanosilica ratios (0.25, 0.5,0.75, and 1%) were mixed with sand with diverse hydraulic conditions and three diverse pier diameters. Results indicate that the nanosilica can be utilized as an alternative solution to lessen the depth of local scour. Nanosilica can be effectively utilized by mixing it with sand. Experimental observation showed that the maximum reduction ratio of the depth of local scour is 59.6% for the case of a 3 cm pier, 42.6% in the case of a 5 cm pier diameter, and 24.65% in the case of a 7 cm pier diameter. The optimum ratios of the nanosilica are 0.25, 0.5, and 0.75%. Furthermore, the effect of using nanosilica on the other factors for the local scour has been demonstrated in this investigation. [ABSTRACT FROM AUTHOR]