Standard and innovative characterization of strength, stiffness, and non-aging creep of concrete at early ages

Author(s): Mario Ausweger, Eva Binder, Olaf Lahayne, Roland Reihsner, Gerald Maier, Martin Peyerl, Bernhard Pichler
Paper category: Proceedings
Book title: SynerCrete’18: Interdisciplinary Approaches for Cement-based Materials and Structural Concrete: Synergizing Expertise and Bridging Scales of Space and Time Vol. 1 & 2
Editor(s): Miguel Azenha, Dirk Schlicke, Farid Benboudjema, Agnieszka Jędrzejewska
ISBN: 978-2-35158-202-2
e-ISBN: 978-2-35158-203-9
Publisher: RILEM Publications SARL
Publication year: 2018
Pages: 321-326
Total Pages: 6
Language : English

Abstract: Quantitative knowledge regarding the early-age evolutions of strength, stiffness, and creep properties of concrete are important for structures that are loaded already a few days after production. This was the motivation to characterize six concretes at early ages. The concretes were made of three types of cements (CEM II / A-M (S-L) 42.5N, CEM II/A-S 42.5R, and CEM I 52.5 R) and two types of aggregates (quartzite and limestone). The content of entrained air ranged from 2 % to 6 %. The standard tests included nondestructive loading- unloading experiments and destructive cube compression tests, performed 1, 3, 7, 14, and 28 days after production. The innovative experiments were performed according to the test protocol by Irfan-ul-Hassan et al. [1]. Three-minutes-long compression tests were performed once every hour, starting 24 hours after production and ending at material ages amounting to 8 days. Thus, each specimen was subjected to a series of 168 ultra-short creep experiments. Three minutes are long enough such that significant creep deformation is measured, and short enough such that the microstructure is virtually constant, i.e. that the chemical reaction between the cementitious binder and water does not progress significantly. Thus, each test provides access to the non-aging creep behavior of a specific material microstructure. Test evaluation is based on linear viscoelasticity, under explicit consideration that significant creep strains develop already during the short loading phase. Evaluation of more than 1000 three- minutes-long compression tests provided access to the hydration-induced evolutions of the elastic Young’s modulus and the creep modulus of the tested concretes [2].

Online publication : 2018
Publication type : full_text
Public price (Euros) : 0.00