ANALISIS PENGARUH KOMBINASI ABU KULIT KOPI DAN LIMESTONE SEBAGAI FILLER TERHADAP KARAKTERISTIK MARSHALL CAMPURAN ASPAL (AC-WC)

Abstract

ABSTRACT

Fillers play an important role in asphalt mixtures by filling the voids between aggregates, increasing the density of the mixture, and influencing Marshall characteristics such as stability, VIM, VMA, and VFB. Therefore, the proper selection of filler material is essential in determining the quality of the Marshall mixture. This study aims to analyze the Marshall characteristics of asphalt mixtures using a combination of coffee husk ash and limestone as filler materials. The filler ratios used in this study were 15% coffee husk ash : 85% limestone and 25% coffee husk ash : 75% limestone. The testing was conducted using the Marshall method in accordance with the specifications of the Bina Marga 2018. The results indicate that the filler ratio closest to the optimum condition was the combination of 15% coffee husk ash and 85% limestone. The test results showed a stability value of 1202.91 kg, a flow value of 2.93 mm, a VIM value of 3.17% at the 15%:85% ratio, a VMA value of 14.79%, a VFB value of 74.39%, and a Marshall Quotient value of 410.14 kg/mm³. Although most Marshall parameters met the required specifications, the VMA parameter with a value of 14.79% did not meet the minimum specification requirement of 15%. The VMA value, which is below the required standard, indicates that the use of a combination of coffee husk ash and limestone has not fully satisfied the requirements to be used as filler in asphalt mixtures based on the Bina Marga 2018 specifications.

Keywords: Coffe husk ash, filler,  Road, asphalt, Limestone