A SIMPLIFIED 1D STRESS APPROACH FOR CRACKING RISK PREDICTION

Author(s): Luis Ebensperger (1)
Paper category: Proceedings
Book title: SynerCrete’18 International Conference on Interdisciplinary Approaches for Cement-based Materials and Structural Concrete
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: 907-912
Total Pages: 6
Language : English

Abstract: Cracks in concrete structures during early ages occur more often than expected. It affects adversely the concrete structure, especially serviceability and durability. The effect of internal concrete volume changes in absence of loads, such as the effect of temperature changes caused by heat of hydration and the chemical/drying shrinkage, is normally not included during design stages. This occurs despite specific recommendations in Codes for situations
when these volume changes are significantly restrained.
This work addresses the development of a simple 1D assessment tool that considers the cement ́s heat of hydration, the thermal and viscous-elastic properties of young concrete, and the degree of external restraint. By performing an iterative calculation procedure for seven days, the model graphically shows the expected core and surface temperature, the
corresponding stress development, and the Cracking Index for different heights of the concrete member. The tool allows to consider parameters, such as mix design, thermal properties including the heat transfer coefficient, placement conditions such temperature during pouring and curing, demoulding time, geometry of the member, and consideration of
chemical and drying shrinkage. Its applicability is discussed for a cast-in-place beam with registered temperature measurements and for a high-cracked wall foundation system of a liquid containing structure.

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