Experimental Investigation on Erosion of Ultrahigh-Performance Concrete with Short-Distance Water Impact Method

This paper aims to propose a short-distance water impact method to test the hydraulic erosion resistance of ultrahigh performance concrete materials (UHPC). The method used high-velocity water flow to simulate a complex hydraulic erosion environment, and an erosion zone was applied to evaluate the erosion resistance of materials. The erosion depth and mass loss of the specimens were tested. The results showed that a water pressure of about 2 MPa can be applied by short-distance water impact. At an impact time of 3 h and an impact distance of 1 cm, the erosion depth and mass loss of specimens were maximized. Thereinto, the erosion depth of mortar was 37.6% higher than that of UHPC. The mass loss of UHPC was 40.7% lower than that of mortar. Three indices for evaluating erosion resistance, including erosion rate expressed in %, erosion rate expressed in g/h, and erosion resistance strength, were compared. In addition, the erosion rate expressed in % could take into account the instantaneous state of the erosion process and reflect the deterioration trend with respect to impact time. According to the surface fitting, a predictive model between the erosion rate and impact condition was established. The variation trend of UHPC will be flat after a long period of erosion. The underwater method is compared, and the field test result is discussed.