Concrete heritage: Tentative guidelines for the ‘Patch Restoration Method’

Author(s): J. Valença, C. Almeida, E.S. Júlio
Paper category: Conference
Book title: Concrete Repair, Rehabilitation and Retrofitting III (ICCRRR)
Editor(s): M.G. Alexander, H.-D. Beushausen, F. Dehn, P. Moyo
Print ISBN: 978-0-415-89952-9
Publisher: Taylor & Francis Group
Pages: 369- 370
Total Pages: 2
Language: English

Abstract: 
Most outstanding constructions of the XXth Century were built in concrete. Some of these, due to their architectural, historical and/or cultural relevance, are part of the World’s heritage. In order to preserve this legacy, interventions must be performed according to very strict restoration requirements. However, when referring to concrete, there is an almost generalized lack of concern relatively to this subject. The study described focuses on a wide spread repairing method of concrete structures, known as ‘Patch Repair Method’. This method consists in removing deteriorated concrete from small areas and replacing it by repairing mortars. However, the Patch Repair Method cannot be used straight forward in concrete heritage since, besides durability, material compatibility and structural performance, it is also important to draw special attention to color and texture matching between the original concrete substrate and the repairing mortar. Tentative guidelines are provided relatively to the application of the Patch Repair Method to concrete heritage. A new method is presented, herein called ‘Patch Restoration Method’, covering the whole process, from assessment to intervention. It includes the following main steps: (i) evaluation of color and texture in the neighborhood of the area to be repaired using image processing; (ii) design and application of a customized repairing mortar, with specific color and texture requirements to match the substrate, also taking into account the effect of ageing; and (iii) monitoring the patch restoration, also using image processing. The method was first applied to mortars, designed and tested in laboratory, aiming to calibrate and validate it. Afterwards, a concrete heritage example was considered as case study—the buildings of the Fundação Calouste Gulbenkian in Lisbon, Portugal—to test the method on site. Finally results are discussed, conclusions drawn, and tentative guidelines are proposed to apply the new ‘Patch Restoration Method’ in practice.

Online publication: 2014
Publication Type: abstract_only
Public price (Euros): 0.00