Experimental Study on Anti-Scour Property and Erosion Resistance of 3D Mat Materials for Slope Protection in Waterway Engineering

Abstract

3D mats are environmentally friendly and ecological materials for protecting river and waterway banks. The anti-scour properties of the materials and the erosion resistance of the soil under them can be studied to provide decision support for the selection of slope protection materials and their applicable areas. In this paper, an indoor prototypical scouring experiment with a flume is carried out to study the anti-scour properties of three types of 3D mat materials (vegetation grass mats, Enkamat and reinforced Mike mat) and the erosion resistance of the underlying soil under typical combined conditions of flow rate and water stage. It is concluded that the 3D mats increase the resistance coefficient of the bed surface, and that with the same incoming flow, the average flow velocity is inversely related to the resistance coefficient. There are three scouring modes for 3D mats under the action of water flow: material failure caused by mechanical damage, performance failure caused by serious erosion of the soil mass and non-failure. Of the three mat materials, the reinforced Mike mats are more resistant to scouring than the other two unreinforced materials, and the erosion volume ratios of reinforced Mike mats, vegetation grass mats and Enkamat are 59.24%, 61.81% and 62.17%, respectively, under the same small flow rate and high water stage. The results show that the reinforced Mike mats have the best anti-scour property and soil conservation performance, followed by Enkamat and the vegetation grass mats. In addition, reinforced materials outperform non-reinforced ones in their anti-scour performance and their protection for the underlying soil on the bank slope.