Internal curing of mortars by lightweight aggregates and its effects on hydration

Akcay B., Tasdemir M. A.

CANADIAN JOURNAL OF CIVIL ENGINEERING, vol.35, no.11, pp.1276-1284, 2008 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 35 Issue: 11
  • Publication Date: 2008
  • Doi Number: 10.1139/l08-078
  • Journal Name: CANADIAN JOURNAL OF CIVIL ENGINEERING
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.1276-1284
  • Keywords: autogenous deformation, degree of hydration, heat of hydration, high-performance concrete, internal curing, lightweight aggregate, HIGH-PERFORMANCE CONCRETE, MICRO-MACRO CORRELATIONS, HIGH-STRENGTH CONCRETE, CEMENT-BASED MATERIALS, AUTOGENOUS SHRINKAGE, EARLY-AGE, PASTE, MICROSTRUCTURE, DEFORMATIONS, PREVENTION
  • Kocaeli University Affiliated: Yes

Abstract

This study investigates the effects of lightweight aggregates (LWAs) on heat and degree of hydration in high-strength cementitious materials, in which natural pumice LWAs were used as water reservoirs to provide internal curing for mitigating autogenous deformation. Normal aggregates were substituted by LWAs at three different volume fractions, such as 8%, 16%, and 24% of total volume of mortars. The results show that as the amount of LWAs increased, the autogenous deformation significantly decreased, while the heat of hydration increased slightly. The cement particles can easily find water released from LWAs and consequently, the degree of hydration increased due to internal curing. The addition of LWAs caused a delay in the time to approximately reach the asymptotic value of the nonevaporable water content.