Time filter

Source Type

Champs-sur-Marne, France

Bouichou M.,Cercle des Partenaires du Patrimoine | Marie-Victoire E.,CNRS Research Laboratory for Historical Monuments | Francois A.,CNRS Research Laboratory for Historical Monuments | Bousta F.,CNRS Research Laboratory for Historical Monuments | Orial G.,CNRS Research Laboratory for Historical Monuments
Concrete under Severe Conditions: Environment and Loading - Proceedings of the 6th International Conference on Concrete under Severe Conditions, CONSEC'10

Biological covering affects all the concrete buildings. Algae, lichen or moss, not only change the aspect of the colonized surfaces, but also contribute to superficial losses of cohesion. In the field of cultural heritage, where the preservation of the original material and aspect is of major importance, it appeared necessary to study techniques to eliminate such covering, without inducing additional decay. 3 types of biocide products and two water or water vapor-based innovative techniques were tested on a Parisian historical building, colonized by a varied biological covering. Immediately after treatment, the efficiency of the water vapor technique, and the insufficient performance of the biocide products combined with a hand-brushing were evidenced. But, one year and a half after treatment, signs of recolonization were observed on some of the testing areas. So an efficient and durable treatment might combine a water vapor cleaning and a preventive biocide product application. © 2010 Taylor & Francis Group, London. Source

Giovannacci D.,Cercle des Partenaires du Patrimoine | Martos-Levif D.,Laboratoire Of Recheche Des Monuments Historiques Umr3224 | Walker G.C.,University of Reading | Detalle V.,Laboratoire Of Recheche Des Monuments Historiques Umr3224
Proceedings of SPIE - The International Society for Optical Engineering

Terahertz (THz) spectroscopy and imaging is a non-destructive, non-contact, non-invasive technology emerging as a tool for the analysis of cultural heritage. THz Time Domain Spectroscopy (TDS) techniques have the ability to retrieve information from different layers within a stratified sample, that enable the identification of hidden sub-layers in the case of paints and mural paintings. In this paper, we present the THz TDS system developed in the European Commission's 7th Framework Program project CHARISMA [grant agreement no. 228330]. Bespoke single processing algorithms; including a deconvolution algorithm can be deployed to increase the resolution and the global performance of the system. The potential and impact of this work is demonstrated through two case studies of mural paintings, where the capability to reveal the stratigraphy of the artworks is demonstrated. © 2013 Copyright SPIE. Source

Costa V.,Cercle des Partenaires du Patrimoine | Texier A.,CNRS Research Laboratory for Historical Monuments
Journal of Solid State Electrochemistry

When restoring historical monuments, it is often verified that reinforcements, mostly made of ferrous alloys, are in quite a bad state and must be partially or totally replaced to prevent further degradation or accidents. Modern alloys such as stainless steels are increasingly used for such purpose, which raises the open question concerning their compatibility with the new types of sealing products available on the market. Even though it is not possible to use accelerated tests to give a livelong guarantee of adequacy of materials combination, electrochemical tests of metals in an aqueous extract of the sealing products could be used as screening to rapidly identify situations that would conduce to the premature corrosion of the metal. © 2009 Springer-Verlag. Source

Bouichou M.,Cercle des Partenaires du Patrimoine | Marie-Victoire E.,CNRS Research Laboratory for Historical Monuments | Cailleux E.,Center Scientifique Et Technique Of La Construction | Sommain D.,Center Technique Louis Vicat
RILEM Bookseries

In the French Alps, near Grenoble, in the middle of the nineteenth century, natural cements were massively used to produce "cast stone" (concrete block) and to simulate natural yellowish to reddish cut stone. In a first project, several historic concrete buildings were studied, and a major decay mechanism was identified: erosion, leading to the loss of the original fake stone appearance. Today, due to a lack of appropriate repair materials, grey Portland cement-based mortars and paintings are used, leading to a complete loss of the original aspect. Therefore, the aim of this second study was to develop and test compatible repair materials to conserve the cultural heritage of this region. Based on the results of the first project, specifications concerning the composition and main properties of compatible repair materials were established. Then, four mortars were selected, two of them being specifically formulated. In a second step, the intrinsic properties of those mortars were characterised, and finally, their mortar/concrete compatibility was assessed. © RILEM 2012. Source

Giovannacci D.,Cercle des Partenaires du Patrimoine | Leclaire C.,Cercle des Partenaires du Patrimoine | Horgnies M.,Cercle des Partenaires du Patrimoine | Ellmer M.,Lafarge | And 4 more authors.
Construction and Building Materials

Algal growth is responsible for aesthetic defects on roofing tiles. Accelerated water-streaming tests were done on different building materials. The results establish the ranges of porosity and roughness that can initiate the colonization under humid saturation. A smooth surface is then recommended to reduce the settlement. Experiments done on limestone and clay tiles demonstrate that coupling high porosity and rough surface should be banished to avoid any rapid algal colonization. However, the alkaline composition of concrete tiles can strongly affect the algal settlement, whatever their intrinsic porosity and roughness. Observations by Environmental Scanning Electron Microscopy show that calcite crystals could promote the settlement of algae on the surface. © 2013 Elsevier Ltd. All rights reserved. Source

Discover hidden collaborations