The Restoration of the Nativity Church in Bethlehem

This book is a summary of the main restoration works carried out at the Church of the Nativity in Bethlehem that commenced in September 2013. Work on roof wooden structures, wall and floor mosaics, internal plasters, wooden architraves and painted columns of the naves, external wall surfaces and Narthex is all presented in a sequence of reports that accompany the reader up to the final interventions through accurate descriptions of historical and archaeological features, initial state of conservation and appropriate techniques of conservation and restoration. Topics are treated with the methodological and linguistic rigor specific to each disciplinary sector involved even if, in the interest of making reading and comprehension easier, it was sometimes preferred to present only significant case studies, which are nevertheless representative of groups of wider and more complex problems. Through the reading of this work, the reader can simply fulfil his desire for knowledge and obtain answers to certain curiosities about the past history of the Church. At the same time, useful guidelines in dealing with conservation and restoration interventions at historic-architectural sites of similar complexity can be found. The book is, therefore, addressed to a generic reader, interested in the history and conservation of one of the most representative examples of our heritage, but also, in light of its technical and scientific value, to university students, technicians, restorers, architects, structural engineers, archaeologists and historians.

1 Introduction Presidential Committee for the Restoration of the Church of the Nativity and C. Alessandri 2 The restoration site Piacenti S.p.A., C.D.G. – Community Development Group and C. Alessandri2.1 Team configuration 2.2 Preliminary on-site tests 2.3 Organization of the work site 2.4 Supply of materials and facilities 3 Roof and windows 3.1 Historical analysis G. A. Fichera3.2 Morphologic and structural characteristics of the roof C. Alessandri, N. Macchioni, M. Mannucci, M. Martinelli and B. Pizzo3.3 The scaffolding C. Alessandri and M. Martinelli3.4 State of conservation of the wooden structures N . Macchioni, M. Mannucci , M. Martinelli and B. Pizzo3.5 Wooden species and dating of the wooden structural components M . Bernabei, J . Bontadi, N. Macchioni and M. Mannucci3.6 Interventions on trusses, purlins and boards C. Alessandri, V. Mallardo, M. Martinelli and B. Pizzo3.7 Archaeological analysis G. A. Fichera3.8 Vulnerability analysis and seismic reinforcement C. Alessandri, V. Mallardo and M. Martinelli3.9 Old and new roof covering C. Alessandri and M. Martinelli3.10 Windows S . Palanti3.11 Maintenance C. Alessandri, N. Macchioni, M. Martinelli and B. Pizzo 4 Mosaics 4.1 Historical analysis M . Bacci4.2 Materials and techniques S . Sarmati, N. Santopuoli and E. Concina4.3 Mosaics materials analysis M . Verità, L. Lazzarini and P. Santopadre4.4 The photogrammetric survey of the mosaics 216G. Caratelli and C. Giorgi4.5 State of conservation S . Sarmati, N. Santopuoli and E. Concina4.6 Interventions S . Sarmati, N. Santopuoli and E. Concina4.7 Floor mosaics – archaeological excavations G.A. Fichera 5 Plasters S. Sarmati and N. Santo Puoli5.1 Material composition 5.2 State of conservation 5.3 Interventions 6 Paintings on columns 6.1 The figurative cycle M . Bacci6.2 State of conservation S . Sarmati6.3 Interventions S . Sarmati 7 Exterior wall surfaces 7.1 Materials and their state of conservation S . Sarmati and G. A. Fichera7.2 Intervention techniques on stones and mortar joints S . Sarmati 8 Wooden architraves C. Alessandri, N. Macchioni, M. Mannucci, M. Martinelli and B. Pizzo8.1 Internal geometry, material and technical characteristics 8.2 External decorations 8.3 State of conservation and past interventions 8.4 The new interventions 8.5 The problem of the corners 8.6 Maintenance 9 The narthex 9.1 Archaeological analysis and preliminary structural survey C. Alessandri, G. A. Fichera and M. Martinelli9.2 On-site material survey C. Alessandri and M. MartinelliIQM 9.3 Interventions of restoration inside the narthex C. Alessandri and M. Martinelli9.4 Interventions of structural consolidation C. Alessandri and M. Martinelli9.5 Numerical simulations and on-site tests C. Alessandri and M. Martinelli9.6 The Armenian door M . Bacci and S. Sarmati9.7 Maintenance C. Alessandri and M. Martinelli 10 Monitoring C. Alessandri, N. Macchioni, M. Martinelli and B. Pizzo10.1 Narthex 10.2 Church façade 10.3 Walls of the nave 10.4 Orthodox wall (south wall) 10.5 Corners 10.6 Columns 10.7 Wooden architraves 10.8 Roof wooden structures 10.9 Fire and micro-climate detection system

Claudio Alessandri graduated in Architecture at the University of Florence, Italy in 1976. In 1983 he was appointed Assistant Professor in Mechanics of Solids & Structures at the same University. In 1991 he became Associate Professor and two years later he moved to the University of Ferrara where in 2011 he became Full Professor and later Head of the Architecture Department from 2003 to 2005. In the same years he was also Director of D.I.A.P.Re.M, a University Research Centre with experience and expertise in 3-D laser scanning, diagnostic analysis, conservation & restoration of monuments and sites, sustainability, management of territory & landscape. Since 2012 he is part of the Engineering Department Staff of the University of Ferrara. From 2010 to 2015 he was Deputy Rector of the University for matters regarding the University Real Estate assets. He was Visiting Professor at foreign Universities and Cultural Centres: PUCPR - Pontificia Universidade Catolica do Paranà – Brazil; TUD – Technische Universität Dresden – Germany; Shenzhen University – China; Birzeit and Al Quds Universities – Palestine¸ RIWAQ Center for Preservation of Historical Heritage – Ramallah, Palestine; Welfare Association – Jerusalem, Palestine. In 2010-2011, after previous work experiences with UNESCO in Palestine, he coordinated the International team appointed by the Palestine National Authority to survey and analyse the state of conservation of the Church of the Nativity in Bethlehem. The report delivered to the P.N.A. became the main reference for the restoration works started in 2013, of which he is still one of the main supervisors. Presently his main research fields are Computational Mechanics, Numerical Modelling and Structural Analysis for Heritage Preservation.