The effect of aggregate type and gradation on fragmentation resistance performance: Testing and evaluation based on different standard test methods

Aggregates used in construction works must be sufficiently durable in that long-lasting performance. Aggregates are exposed to external loads and harsh environmental conditions in all processes from manufacturing to use in the field. These cause fragmentation, abrasion, polishing of aggregates. Aggregates in different origin show distinct characteristics based on their chemical formation and the physical features at that moment such as shape and size. To make the properties of aggregates clear, series of test are implemented. Fragmentation resistance (FR) test using Los-Angeles apparatus is one of test in the series used to identify the strength of aggregate. This test can be performed based on different standard test methods such as the standard by American Society for Testing and Materials, ASTM and European Committee for Standardization, CEN, which are focused on in the current study. However, these two standards differ from each other in a few aspects such as aggregate size and mass of aggregate and charges. Based on these fundamental differences, a question has arisen about the effect of the aggregate size on the FR based on different origin. Respectively, this study was established on this case by using related ASTM and CEN standard. To achieve the answer, different sources of aggregates including metallurgical slags were supplied and a series of tests were performed on them to identify their physical, mechanical and chemical properties. Thereinafter, FR tests were performed in five different grain size distributions ranging from 2.36 to 37.50 mm according to ASTM C131 and CEN 1097-2. The results showed that aggregates in different origin, as expected, exhibited different FR values. However, there exist significant differences between FR values of aggregates tested in different grain size although the materials are the same. Considering the grain size of aggregate being used in the related works, testing and evaluation of FR performance of aggregate will be more accurate and robust. Therefore, the authors recommended that following ASTM standard for testing FR due to the optional grading will give more precise vision about aggregate’s performance.