Abrasive wear of concrete measured by different accelerated tests and natural exposure

Abstract

Several accelerated methodologies have been created to estimate the abrasion resistance of concrete. The objective of this article was to compare the results of three accelerated abrasion tests with the natural wear of a concrete slab. The inorganic abrasion test (ABNT NBR 12042) was applied in concrete specimens with 28 and 180 days of cure. The wear in this test decreased by approximately 34% and 32% at 180 days of cure when compared to 28 days of cure, considering a journey of 500 m and 1000 m, respectively. Test time by hydraulic abrasion method (ASTM C 1138) significantly affects wear on concrete. However, the greatest wear occurred in the first 24h of testing (about 4.25% loss of mass). The deep abrasion test (ABNT NBR 9781) shows 20.43 mm of wear after 75 cycles of abrasion. Also, the visual appearance of the concrete surface is completely different depending on the type of abrasion test applied. The inorganic abrasion test created a smoother surface, exposing the aggregates. The hydraulic abrasion method generated a rougher surface, with a larger number of pores. Deep abrasion caused wear in a specific region of the specimens. A specimen of each mixture was three-dimensionally scanned before and after abrasion wear tests. Furthermore, the results of 10,400 cycles of natural abrasion in concrete slab showed less wear compared to the results of the accelerated methods.