عنوان مقاله [English]
Abrasion/erosion strength is an important characteristic of concrete, such as when used in pavements or some hydraulic structures. In these cases, usage of some admixtures can help to improve abrasion/erosion strength. In this study, admixtures using nano silica and polypropylene fiber, which can increase abrasion/erosion strength, are used. Determination f brasion/erosion strength is measured based on ASTM C1138, which can evaluate the abrasion/erosion strength of concrete under water and steel ball suspension. This test method simulates the abrasive action of waterborne particles, such as silt, sand, gravel, and other solids. The results show that \ these admixtures can \ remarkably improve \ the \ abrasion/erosion \ strength \ of concrete. But, the abrasion/erosion \ strength of \ concrete \ containing nano silica was greater than fiber concrete. Moreover, the rate of improving abrasion/erosion strength by increasing the amount of nano silica or fiber in the concrete, was reduced. Application of nano silica can improve compressive and abrasion/erosion strength as a linear relation. But, although the use of polypropylene fiber causes better abrasion/erosion strength, it cannot improve compressive strength. In other words, polypropylene fiber can extol the surface properties of concrete. It is shown from the results that application of 1 \% nano silica can increase abrasion/erosion strength up to 40\%, and usage of 0.5 \% polypropylene fiber can improve abrasion/erosion strength up to 30\%. These results help to achieve durable concrete in cases where concrete is prone to abrasion/erosion effects, such as wind, flood traffic load and etc.