ASSESSMENT OF MARBLE WASTE POWDER IN ASPHALT CONCRETE MIXES AS A FILLER PARTICULARLY IN TIGRAY REGION (MAYTSEBRI – SHIRE ROAD UPGRADING PROJECT)

Marble waste has been used in high way construction as a filler substitute in hot mix asphalt paving. Many countries have recently incorporated marble waste powder in to their road way specifications, which had encouraged greater use of the material. The main objective of this research is to investigate the use of marble waste powder as a filler in hot mix asphalt; and specifically to study the effect of adding different percentages of marble waste powder on the properties of asphalt mix comparing with conventional mix properties by Marshal test, and identify the optimum percent of marble waste powder to be added in the hot mix asphalt. In this research a number of aggregate and bitumen tests are conducted to investigate the applicability of using marble waste powder as a filler in hot mix asphalt concrete. Marshal samples are prepared using both aggregates and marble waste powder to investigate the properties of the asphalt mix. By using Marshal Mix design procedure, fifteen hot mix asphalt mixtures with three types of mineral fillers and four proportions of marble waste powder by weight of aggregates were prepared. For each filler content, four hot mix asphalt concrete were prepared. The results showed that it is possible to use the marble waste powder in preparing hot mix asphalt concrete. Marble waste powder contents 2%, 2.5%, 3% and 3.5% with 4.82% bituminous binder and 2%, 2.5% and 3% marble waste powder contents with 4.97% of bituminous binder satisfy the specified requirements of Maytsebri – Shire road upgrading project specifications limit. Marble waste powder content of 2% by weight of aggregate with 4.82% optimum binder content and 2.5% marble waste powder content with 4.97% optimum binder content have higher stability value. The results of this research work is hoped to be used as the basis for further investigation on the effects of mineral fillers and improve asphalt concrete as well as find alternative materials