Experimental study on erosion depth in hydraulic structures

In many hydraulic constructions, such as dams, spillways, and stilling basins, large quantities of concrete can be ruined because of the long-term action of water-borne solids. To a great extent, for hydraulic structures, the durability relies on the resistance that the concrete surface performs against the mechanical wear. The surface damage caused by the uninterrupted material removal process, which induced by the impact of the water-borne solid particles, is termed hydro-abrasion. In nearly all hydraulic structures, this kind of progressive deterioration of the concrete surfaces is observed with different intensities. Obviously, such hydro-abrasive concrete wearing normally results in a reduction in the service life of the hydro-technical facility, and consequently because of the required repairs, the non-functioning of the facility during the repair period results in an expenditure increment. The rate of concrete erosion was tested by the original equipment manufactured in the Construction Laboratory of Civil Engineering department / Wasit University, by directing a high velocity jet of a mixture of water and sand, striking the concrete plates. To satisfy the research requirements, 24 samples of concrete were prepared and categorized into three mixtures with compressive strengths of 25, 35, and 45 MPa, they were tested after 7 days of maturing. Further, the effect of the impingement angle was also determined. Experimental estimations was made of the four different angles (0, 30, 45, and 60 degrees) with the horizon. From the findings of the experimental investigations, it was clear that the maximum erosion depth can be reached when the flow inclination angle was 45 degrees, while the lowest rate can be achieved by the flow inclination angle of 60 degrees with horizon. (C) 2021 Elsevier Ltd. All rights reserved.