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Effect of the service life assessment approach of the environmental benefit of using self-healing concrete in marine environments
To reduce concrete’s susceptibility to cracking, full autonomous healing mechanisms are being studied today. A promising technique consists of incorporating encapsulated polyurethane-based healing agents. Upon crack occurrence, small capsules in close vicinity of the damaged area break. A polyurethane (PU) pre-polymer flows into the crack and after reaction with the surrounding moisture, the hardened PU prevents further accelerated ingress of aggressive substances at the original crack location. So far, promising results have mainly been obtained in proof-of-concept experiments. However, these tests do not allow for a proper estimation of the service life extension and environmental benefit that is possible when using concrete with selfhealing properties. In this paper, such calculations have been performed for marine fly ash concrete with an in-house developed encapsulated high viscosity PU precursor. Since the service life calculation outcome very much depends on the probabilistic prediction model used and the underlying experimental input, two commonly used strategies were considered: one based on natural diffusion tests with chloride profiling at various exposure times and another based on accelerated chloride migration experiments at different ages. The first approach allows for a simultaneous fitting of the chloride diffusion coëfficiënt, surface concentration and ageing exponent, while with the second one the chloride resistance after many years (time infinity) can be taken into account. Both approaches indicate a substantial prolongation of the service life when cracks, 300 pm in width, are healed autonomously, even if only partially. Nevertheless, the outcome of the two prediction methods is not the same (service life: 61-97 years versus 12- 69 years, respectively). Depending on the applied approach, the required number of rehabilitation actions in time for the cracked (reference) concrete varies. As a consequence, service life related life cycle assessment performed in the SimaPro software clearly ...
Effect of the service life assessment approach of the environmental benefit of using self-healing concrete in marine environments
To reduce concrete’s susceptibility to cracking, full autonomous healing mechanisms are being studied today. A promising technique consists of incorporating encapsulated polyurethane-based healing agents. Upon crack occurrence, small capsules in close vicinity of the damaged area break. A polyurethane (PU) pre-polymer flows into the crack and after reaction with the surrounding moisture, the hardened PU prevents further accelerated ingress of aggressive substances at the original crack location. So far, promising results have mainly been obtained in proof-of-concept experiments. However, these tests do not allow for a proper estimation of the service life extension and environmental benefit that is possible when using concrete with selfhealing properties. In this paper, such calculations have been performed for marine fly ash concrete with an in-house developed encapsulated high viscosity PU precursor. Since the service life calculation outcome very much depends on the probabilistic prediction model used and the underlying experimental input, two commonly used strategies were considered: one based on natural diffusion tests with chloride profiling at various exposure times and another based on accelerated chloride migration experiments at different ages. The first approach allows for a simultaneous fitting of the chloride diffusion coëfficiënt, surface concentration and ageing exponent, while with the second one the chloride resistance after many years (time infinity) can be taken into account. Both approaches indicate a substantial prolongation of the service life when cracks, 300 pm in width, are healed autonomously, even if only partially. Nevertheless, the outcome of the two prediction methods is not the same (service life: 61-97 years versus 12- 69 years, respectively). Depending on the applied approach, the required number of rehabilitation actions in time for the cracked (reference) concrete varies. As a consequence, service life related life cycle assessment performed in the SimaPro software clearly ...
Effect of the service life assessment approach of the environmental benefit of using self-healing concrete in marine environments
Van den Heede, Philip (Autor:in) / Van Belleghem, Bjorn (Autor:in) / De Belie, Nele (Autor:in)
01.01.2017
Proceedings of The Eleventh High Performance Concrete (11th HPC) & The Second Concrete Innovation Conference (2nd CIC) Tromsø, Norway 2017 ; ISBN: 9788282080545
Aufsatz (Konferenz)
Elektronische Ressource
Englisch
DDC:
690
| BASE | 2017
| BASE | 2016
Reliability Approach to Service Life Prediction of Concrete Exposed to Marine Environments
| Online Contents | 1996
Reliability Approach to Service Life Prediction of Concrete Exposed to Marine Environments
| British Library Online Contents | 1996