An investigation into the influence of size on the mechanical properties of aggregates

Abstract

Tests have been carried out according to British Standard BS 812-1975 on non-standard and standard size aggregates to study the influence of aggregate size on mechanical properties. Dolerite, granite, limestone aggregates of different sizes have been tested. No basic relations have been found between elongation index, IE, and flakiness index, IF, and the different aggregate sizes. Aggregate impact value, AIV, aggregate crushing value, ACV, and 10 per cent fines loads, however, are aggregate size dependent. Tests on larger aggregate sizes give higher test values, whereas tests on smaller aggregate sizes give lower values than test results for standard size aggregates. For each rock type there is a different set of sieve sizes, from those recommended in BS 812-1975, which give the same values as the standard sieve sizes. Additionally, relations have been determined for the mechanical test results for the different size aggregates.