Comparative analysis on the anti-wheel impact performance of steel fiber and reticular polypropylene synthetic fiber reinforced airport pavement concrete under elevated temperature aging environment

Abstract

In this paper, the reticular polypropylene synthetic fiber concrete (RPSFC) (the representative of organic fiber concrete) and Steel fiber concrete (SFC) (the representative of inorganic metal fiber concrete) have been prepared. The experiments were carried out by the polyurethane high-temperature aging chamber, the xenon weather resistant test box and the modified wheel type impact test machine. The internal mechanical properties and external damage of concrete under the joint action of high temperature aging and dynamic wheel type impact were compared and analyzed, and the influence degree of fiber type and content is summarized. Some specific damage indexes were selected to evaluate the Anti-wheel impact performance of the pavement concrete, namely the loss of compressive strength, the loss of dynamic modulus, the growth size of internal pore and the surface impact damage. The results showed that adding fiber in the concrete can control the increase of indexes. The indexes of the specimen increase with the increasing test rounds, but decrease with the increasing fiber volume content. Through the comparative analysis of indexes, we found that the effect of steel fiber is more obvious under long-term action. Combined with the internal thermal imaging processing of fiber concrete, it is found that the steel fiber can obviously control the aging and cracking of concrete matrix and the expansion growth of internal pore. Generally speaking, the most effective way to improve the anti-wheel impact performance of concrete under elevated temperature aging environment is to add 1.5% metal fiber (SF).