The role of shrinkage reducing admixtures and supplementary cementitious materials in volume stability and strength development

Ioanna Papayianni,Philip Henes Alt,Fotini Kesikidou,M.G Grantham,C Mircea

doi:10.1051/matecconf/201928902005

Ioanna Papayianni, Philip Henes Alt + Show 3 more

Open Access

https://doi.org/10.1051/matecconf/201928902005

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Abstract

Shrinkage is one of the main reasons for mortar and concrete failures like curling, crack formation and de-bonding. It is a complex phenomenon due to many factors involved, such as the type and amount of cement, water to binder ratio, binder to aggregates ratio and the type and granulometry of the aggregates, relative humidity, air temperature and the temperature of concrete. To reduce this phenomenon, Shrinkage Reducing Admixtures (SRAs) have been studied over the last 30 years. On the other hand, investigation in the field of Supplementary Cementitious Materials (SCMs) has indicated that their use in concrete may improve its volume stability depending on their percentage and the type of the material. In this paper, the addition of a Shrinkage Reducing Admixture and Supplementary Cementitious Materials like ladle furnace slag, calcareous fly ash and limestone filler, were investigated. Their influence, separately and in combination, in volume stability and strength development of cement mortars was identified. Capillary absorption and open porosity were also determined.

Highlights

Shrinkage is one of the main reasons for mortar and concrete failures like curling, crack formation and debonding
The effectiveness of Shrinkage Reducing Admixtures (SRAs) seems to be influenced by the binders of the mortars
The performance of it is clearly positive in mortars with CEM I42.5, but in the case of use of Supplementary Cementitious Materials (SCMs)(s) the reduction in shrinkage deformations is dependable on the binding system and further investigation is needed to describe the SRA performance with different type SCM(s) in the system

Summary

Introduction

Shrinkage is one of the main reasons for mortar and concrete failures like curling, crack formation and debonding. To reduce this phenomenon, Shrinkage Reducing Admixtures (SRAs) have been studied over the last 30 years. The addition of a Shrinkage Reducing Admixture and Supplementary Cementitious Materials like ladle furnace slag, calcareous fly ash and limestone filler, were investigated. Their influence in volume stability and strength development of cement mortars was identified.

Mixing

Mechanical characteristics

Physical characteristics

Findings

Conclusions