ABSTRACT
Abstract Autogenous length changes of concrete mixes in which the dense aggregates were replaced partly or wholly by lightweight aggregate particles are described. Replacement percentages were 10%, 17.5%, 25% and 100%. The aggregates of the full lightweight aggregate mixes were saturated completely or only up to 20 or 60%. The test specimens were cured under sealed conditions at 20 °C. Besides the length changes during hardening the strength development was determined. The tests confirmed that use of water containing lightweight aggregates affect the early volume changes drastically. The potentialities of modeling the phenomena which are expected to be responsible for the reduction of autogenous volume changes are dealt with. Keywords: Autogenous shrinkage, lightweight aggregate, blended aggregate, degree of saturation, self desiccation, numerical modeling.
