Influence of coarse aggregate size and type on the design thickness of rigid pavements for Indian conditions

Abstract

The pavement quality concrete (PQC) is used in the construction of rigid pavements, commonly called concrete pavements. The coarse aggregates (CA) are the major constituents of the PQC mix, which influence the strength of the PQC mix. The strength of the PQCmix used in the construction of rigid pavements is one of the major factors that govern the design thickness of these pavements. In this study, an attempt has been made to characterize the influence of CA size and type on strength characteristics of the PQC mix experimentally. The crushed basalt and granitic CA are used in the preparation of the PQC mix. Also, three different nominal maximum aggregate size (NMAS) 19, 26.5 and 31.5 mm, are selected based on the IRC 44: 2017 guidelines. The experimental results are given as input in EverFE 2.24 software for determining the safe design thickness of rigid pavement over the design period. It is concluded that the safe design thickness of the PQC mix prepared using basaltic CA is comparatively lower than the PQC mix prepared using granitic CA for the same NMAS. Also, the safe design thickness of concrete pavement increased with an increase in NMAS irrespective of CA type. Thus, it is suggested to use stronger CA with lower NMAS based on the availability at the site.