Determining the Physical Properties of Aggregate Products and its Suitability for Road Base Construction, Ethiopia

Abstract

Normal aggregates are commonly mined from larger rock formations through an open quarry; the mined rock is reduced to usable proportions by crushing machine. From those materials in construction projects, the widely used one is a natural aggregate, which is a collective term for the mineral materials such as sand, gravel, and crushed stone that are used with a binding medium. Aggregates are one of the major components of highway material which is basically used in highway pavement layers such as base course. For the determination of the suitability of coarse aggregates as a road base construction material, conducting an appropriate physical test was essential. The study was carried out to determine some of the physical properties of natural aggregate products which are obtained around Arba Minch area. For naturally obtained basaltic parent rock, aggregate crushing plant in three different sites around Arba Minch were established, considering the availability of aggregate products of the study area and to approve its suitability, the physical tests of aggregate were conducted by the research team using Sieve test, Impact test, Aggregate Crushing Value test, Aggregate Abrasion Value test, Specific Gravity and Water Absorption test are the tests that have been carried out to evaluate the engineering properties of the natural rock aggregates. Laboratory test result concluded from the three quarry sites (Kulfo, Secha, and Mirab Abaya) showed that the natural aggregates manufactured in Arba Minch areas are good for road base construction because the test result satisfies the ERA, AASHTO, and ASTM specification requirements. Finally the research group concluded the study by providing essential recommendation for further study on the suitability of aggregate qualities for road base construction around the study area, so it will be better to conduct chemical tests of the aggregates because the site has many aggregate source so as to allocate the good product to other required areas.