Influence of flaky aggregate towards creep and resilient modulus on asphalt concrete 20

Abstract

The aim of this paper is to investigate and evaluate the characteristics of flaky aggregate shapes that specifically towards creep and resilient modulus. The maximum allowable aggregate size selected specifically for this study is size 20 mm. In general, flakiness aggregates are being avoided in asphalt concrete mixture simply because these types of properties have significant influence of towards gradation and interlocking characteristic of the aggregate. Due to this significant influence of flaky aggregate, it is recommended that the proportion of flaky aggregate should be limited. Therefore, based on the Jabatan Kerja Raya (JKR) and Malaysian Standards (MS), it specified that the maximum allowable flakiness should be less than 25% in asphalt concrete mixture. This study is only focusing on asphalt concrete mixture that consists of 10%, 20% and 30% proportion of flaky aggregate. The objective of this study is to determine the relationship between resilient modulus against percentage of flaky aggregates in the asphalt concrete mixture. This study also looks on the influence different percentage of flaky aggregates towards dynamic creep properties in a mixture. Hence, several tests like Marshall Tests, Resilient Modulus test and dynamic creep test were conducted. Based on Marshall Tests, the optimum asphalt content obtained for 10%, 20% and, 30% was 5.6%, 5.7% and 5.8% respectively. The findings of this research are the value resilient modulus and stiffness modulus decreases as the amount of flaky aggregate increases.