Use of Dynamic Modulus of Elasticity to Assess the Durability of Self Consolidating Concrete

Abstract

This paper presents the effect of freezing-thawing on self consolidating concrete (SCC) that contains different percentages of fly ash (FA) and air entraining agents (AEA). The effect of freezing-thawing on concrete is assessed on the basis of the change in the dynamic modulus of elasticity. The dynamic modulus of elasticity is determined from both ultrasonic pulse velocity and resonant frequency tests. An in-house resonant frequency test apparatus was developed using an accelerometer and a data acquisition system. During the development of the test apparatus, structural eigenvalue analysis was also utilized to understand if the correct modal frequency of cylindrical test specimens is detected or not. The dynamic modulus of elasticity is then used to compute the durability factor of SCC specimens that are subjected to freezing-thawing cycles. The relationship between durability factor – FA – AEA content was evaluated, and the highest degree of reduction in durability factor was observed at mixes including maximum FA content, and no AEA and maximum AEA content. Furthermore, when FA was used in the range of certain limits, it was observed that SCC specimens were resistant to freezing-­thawing cycles.