I am very pleased to introduce this special issue of the Coudenberg archaeological site, situated at the heart of the city of Brussels. The project is the culmination of twenty-five years of archaeological work, which have progressively enabled different areas of the site to become accessible to the public. Not all the components of the site have been preserved in the same condition and the project faced considerable challenges in both conservation and presentation. Indeed, the presentation of subterranean archaeological remains anywhere requires a well-considered approach to management and conservation strategies, and this site posed some important challenges: these will be of direct relevance to many other sites. The systematic analysis of climate, salts, and mortars, for example, are clearly and closely related to the conservation approaches.
The first paper — by Laetitia Cnockaert, Stéphane Demeter, Aude Henriques de Granada, and Frédérique Honoré — provides a background to the former Palace of Brussels. It also explains the context of the site, with its complex management (it is owned by the City of Brussels and the Brussels-Capital Region, and managed by the not-for-profit association ‘Palais de Charles Quint’), the variety of stakeholders, and the wider context of the continuing programmes for developing, promoting, and preserving the remains.
Paper 2 — by Roald Hayen, Hilde De Clercq, and Sebastiaan Godts — examines the climatic studies that were undertaken to inform the conservation and presentation strategy. These explored the delicate balance between the requirements for public health and safety, and the protection of the archaeological remains from future degradation. Controlling the climate is often essential for a preventive conservation strategy. Potential risks and possible interventions are outlined.
Paper 3 — by Hilde De Clercq, Sebastiaan Godts, and Roald Hayen — explores the long-term underground conservation conditions and especially salt migration into the architectural remains. With in situ architecture one mostly finds complex salt mixtures, which makes the conservation strategy much more difficult. Work was undertaken to model the environmental conditions in order to predict the crystallization behaviour of salt mixtures. This was followed up with Paper 4 — by Hilde De Clercq, Laurent Fontaine, Roald Hayen, and Sebastiaan Godts — which describes the results of drill resistance measurements to evaluate the mechanical damage resulting from salt crystallization pressures.
Paper 5 — by Laurent Fontaine, Roald Hayen, Sebastiaan Godts, and Hilde De Clercq — discusses the characterization of historic mortars by means of a concise methodology of material analyses, providing crucial information on raw materials and ancient mortar technology. Paper 6 — by Sebastiaan Godts, Roald Hayen, and Hilde De Clercq — then builds on this to discuss the different grouting and repair mortars that were developed and evaluated for the conservation and restoration of fragmented bricks in the walls and floors.
Notes on contributors (in alphabetical order)
Correspondence to: Royal Institute for Cultural Heritage, KIK-IRPA, Jubelpark 1, 1000 Brussels, Belgium
Aude Henriques de Granada is an advisor at the Coudenberg Archaeological Site.
Frédérique Honoré is the Director of the Coudenberg Archaeological Site.
Hilde De Clercq is a chemist and obtained a PhD in polymer chemistry at the University of Ghent (1993). From 1994 she worked as researcher in the department Laboratories of the Royal Institute for Cultural Heritage, Brussels, and from 2006 she has been Head of this Department, as well as the head of the section Monuments. She has a broad experience in the diagnosis of the state of conservation of monumental constructions and material-technical research of stone built material; the identification and application modalities of conservation products for monuments; and risk assessment of salt laden building materials. She is a member of numerous committees, including being President of the Permanent Scientific Stone Committee; Member of ‘Conseil de Gestion du Centre Européen d’Archéométrie’, Université de Liège; Member scientific committee «Vlaams-Nederlands natuursteendagen»; Belgian representative on the Executive Board of the Joint Programming Initiative Cultural Heritage; Belgian participant ICCROM FORUM ‘Conservation Science’; Member of the Council of ICCROM.
Correspondence to: Hilde De Clercq. Email: [email protected]
Laetitia Cnockaert is an historian and Scientific Advisor at the Coudenberg Archaeological Site.
Laurent Fontaine is currently a geoscientist in the Monument Laboratory at the Royal Institute for Cultural Heritage (KIK-IRPA). In 2009 he obtained a Master’s degree in Geological Sciences at the Free University of Brussels (ULB). After a one-year job as a professional guide at the Royal Belgian Institute for Natural Sciences, he joined the interdisciplinary team of KIK-IRPA. His fields of experience are: provenance determination of natural stones by thin-section petrography, characterization of historic mortars, and evaluation of consolidating treatments on deteriorated building materials.
Correspondence to: Laurent Fontaine. Email: [email protected]
Roald Hayen graduated in 1997 as civil engineer at the Catholic University of Leuven, K.U. Leuven. Thereafter, he followed the master course in Conservation of Historic Towns and Buildings at the Raymond Lemaire Centre at the same institute. His professional career started at the K.U. Leuven, civil engineering department, as well, where he joined in 1999 as a researcher the EU-funded research project ?Pointing?, dedicated to the damage-analysis and repair of pointing in our cultural built heritage. When the project ended, he worked for several years as the technical-commercial responsible for an international distributor of lime mortars and mineral paints. Since November 2008 he has been working at the Royal Institute for Cultural Heritage, a federal scientific institution dedicated to the study, conservation, and development of Belgium’s cultural heritage, where he combines research and on-site services for specific restoration projects. He gained a broad experience both in the field of research and practical advice with regard to the restoration and conservation of our cultural built heritage. His research fields mainly concentrate on the characterisation of (historic) mortars and renders, the study of the mechanical, physical, and chemical aspects of the compatibility of building materials encountered in historic masonry structures, and the hygrothermal behaviour of buildings as a whole.
Sebastiaan Godts is currently a conservation scientist in the Monuments Laboratory at the Royal Institute for Cultural Heritage, KIK-IRPA in Brussels Belgium. In 2007 he obtained a Master’s degree in Conservation and Restoration of stone and stone-related materials at the University of Antwerp. After his studies he worked as a restorer in private practice and completed an internship in the Conservation Department at KIK-IRPA. In 2009 he obtained a Grant for a Graduate Internship in the Department Field Projects at The Getty Conservation Institute in Los Angeles. His research activities concern the conservation of sculptures, mosaics, monuments, and archaeological sites with a specialization in materials contaminated by soluble salts.
Correspondence to: Sebastiaan Godts. Email: [email protected]
Stéphane Demeter is an historian, First Attaché to the Direction des Monuments et des Sites of the Brussels-Capital Region, President of the Board of Directors, and member of the Scientific Committee of the Palais de Charles Quint ASBL.