Influence of Types of Coarse Aggregates on the Coefficient of Thermal Expansion of Concrete

Abstract

The coefficient of thermal expansion (CTE) was determined for a typical concrete-paving mixture made with six different types of coarse aggregates belonging to the basic class of glacial gravel, quartzite, granite, diabase, basalt, and dolomite. The CTE, compressive strength, and splitting tensile strength of fifteen different concrete mixtures were determined at the age of 28 days. Two parameters, CTE and splitting tensile strength, are the basic input in AASHTO’s new mechanistic-empirical pavement design method. The study revealed a noticeable variation in the values of the CTE of concrete with different types of aggregates. Concrete with quartzite aggregate had the highest value of the CTE followed by dolomite, glacial gravel, granite, and diabase or basalt. The estimated value of the splitting tensile strength of concrete, considering its compressive strength and using AASHTO’s Mechanistic-Empirical Pavement Design Guide for Level 2 design of concrete pavements was discovered to be significantly lower (17–31%) than its actual experimentally determined value.