Influence of limestone filler and of the size of the aggregates on DEF

TL;DR

This study investigates how limestone filler and aggregate size influence delayed ettringite formation (DEF) in concrete, revealing that limestone filler does not inhibit DEF and that aggregate size affects swelling behavior.

Contribution

It provides new insights into the effects of limestone filler and aggregate size on DEF, highlighting their roles in concrete expansion and swelling kinetics.

Findings

Limestone filler does not inhibit DEF.

Swelling kinetics depend on aggregate size.

Volume fraction of aggregates affects swelling rate.

Abstract

This experimental study aims to determine the effect of limestone filler on concrete expansion due to delayed ettringite formation (DEF). Different mortars made with different sizes and percentages of limestone filler and Portland cement CEM I 52.5N are conserved in water. The expansion of the specimens is measured. Results show that DEF is not inhibited by limestone filler. The kinetics and the amplitude of the swelling depend on the size of the limestone filler. The volume fraction of aggregates changes only the kinetics: the relation between swelling and water uptake depends only on the size of the aggregates.