Estimation method for thermal expansion coefficient of concrete at early ages

Title: Estimation method for thermal expansion coefficient of concrete at early ages
Author(s): Mitsuo Ozawa, Hiroaki Morimoto
Paper category : conference
Book title: International RILEM Conference on Volume Changes of Hardening Concrete: Testing and Mitigation
Editor(s): O. M. Jensen, P. Lura, K. Kovler
Print-ISBN: 2-35158-004-4
e-ISBN: 2351580052
Publisher: RILEM Publications SARL
Publication year: 2006
Pages: 331 - 339
Total Pages: 9
Nb references: 7
Language: English

Abstract: In this study, we propose an estimation method for the thermal expansion coefficient of concrete at early ages. In the method, the thermal expansion coefficient is estimated by using a multi-layer model and a maturity equivalent to the initial and final setting time. Concrete is assumed to be an isotropic three-layered material (cement, water and aggregate) in the period between the initial setting and the final setting. In the subsequent final setting, it was assumed to be a two-layered material (cement paste and aggregate). The proposed method was applied to estimate the thermal expansion coefficient of a normal strength concrete (water cement ratio 0.57, 28 days strength 34 MPa) and of a high-strength concrete (water cement ratio 0.3, 28 days strength 80 MPa). The thermal expansion coefficient of the normal strength concrete was measured with non-contact CCD laser displacement-meter. The estimated values of normal concrete tended to be slightly smaller than the experimental results. On the other hand, the estimated values for high strength concrete tended to be slightly larger than the experimental results. It was concluded that the thermal expansion coefficient through the setting phase and the hardening phase can be estimated with adequate accuracy by using the proposed method.

Online publication: 2006-07-30
Publication type : full_text
Public price (Euros): 0.00
doi: 10.1617/2351580052.035