ABSTRACT
Incidentally, it is necessary to clarify the estimation method of Young’s modulus of aggregate and the influence of parameter Esp/Ea on Young’s modulus of concrete.
REFERENCES
Creep, Shrinkage and Durability Mechanics of Concrete and Concrete Structures – Tanabe et al. (eds) © 2009 Taylor & Francis Group, London, ISBN 978-0-415-48508-1
ABSTRACT: For improving the properties of concrete, fly ash and Blast furnace slag (BFS) is mixed with ordinary Portland cement (OPC). These blended concrete has a high resistance to chloride ingress by reducing large pores at later age. This is because fly ash and BFS is reacted with calcium hydroxide and then produce calcium silicate hydrate (C-S-H) gel which expand in cement matrix. It was well known that blended concrete has advantages such as low porosity and low calcium hydroxide content. However, the properties of C-S-H in blended concrete are not cleared well because its structure is changed with mineral admixtures. To understand the structure of C-S-H is important for predicting the properties of concrete. Recently, to determine the mechanical property of C-S-H, nano-indentation method is applied for hardened cement paste by Ulm et al. In their study, this method is only applied for OPC only or degraded OPC until now. Therefore, we applied this method for measuring the elastic modulus of blended hardened cement paste and also measured compositions of blended cement paste by backscattered electron image. As a result, the elastic modulus of HCP mixed with fly ash is lower than that of HCP only. It is indicated that the elastic behavior of C-S-H in blended cement is different from that in OC.
