WoodCultHer

Focused Meeting of COST Action IE0601 and CULTURA Project “Les Toits de l’Europe II”

Joint meeting Florence (May 21-22, 2009)

Structural Typologies and Conservation of Roof Timber Structure

Short Scientific Report

The meeting, organised by DISTAF (a Department of Florence University), was structured according to three presentation sections (Structural typologies, dating and intervention techniques) and visits to important timber structures of the City. In two days, about 20 presentations (orals and posters) have been given by Delegates. At the end of the meeting, during a plenary discussion, the following major outcomes and addressing remarks have been settled:

1) Ancient timber structures are not only a static problem to be managed in order to guarantee structural safety, but they also must be considered as depositaries of many further and important cultural values. As consequence, when  historic timber structures, whether buildings or parts of a building, or their components or members, are being assessed in connection with a project of development or modification, there is a risk that after the assessment, and perhaps as a result of it, the structures or components will be destroyed or significantly modified. It is therefore essential that the assessment include an archaeological record of the structures or components, and of their context, and including both photographs and measured drawings with scales, and if relevant, video material, all clearly dated and labeled.

2) Within technical information to be recorded, structure dating is a very important issue, both for the indication of building construction phases and for information that could be contained in old timber element (i.e. climatology and ecology).

3) Assessment of both structure and members is another key aspect for structures conservation and safety. Visual inspection is emerged as a fundamental step of the processes (both for assessment of biological and physical/mechanical damages). Of course the inspection effectiveness can be significantly improved by means of different non-destructive techniques (i.e. ultrasound, stress waves, sonic tomography, drilling devices) and especially from combination of two or more of them. Determination of both MOE of the whole structural elements, and identification of residual cross section of the beams, are two aims satisfactorily achieved by current knowledge, while still open, and necessary of further research work, are:

Assessment of actual residual strength of old timber;

Identification of classes of damage;

Determination of strength classes for old timber (even if it is really possible).

4) The necessity of developing a data base of experimental results, and to set material banks in which collect old timber elements, have been highlighted as two of the most important needs for development of future research works.

5) A brief summary of the most important outcomes of the focused meeting on standards for wooden cultural heritage, held in Krakow on April 2-3, 2009, has been presented by H. Cruz. The need of developing Guidelines and Standards for assessment and conservation of historical timber structure has been confirmed as a priority task to be developed in this field.

Scientific Program

Thursday May 21, 2009-

09,00 – 09,45 Uwe Noldt, (Germany) – Warm air treatment in the roof of Aachen Cathedral (Octogon and two Chapels) Monitoring and Control of Wood destroying insects

10,00 – 13,00 Visit to roof timber structures of S.Marco Church

14,00 – 14,30 Eleftheria Tsakanika (Greece) “Restoration problems of historical timber roofs in Greece”

Dating of wooden members and structures

14,30 – 15, 15 P.Hoffsummer (Belgium), “Dendrochronology appllied to dating of timber structures

15,15 – 15,35 O. Pignatelli (Italy) Venice: from the origins of the city to the magnificence of the Serenissima Republic

15,35 – 15,55 I.Botar (Romania), Potentials and role of dendrochronology for the interpretation of the historical timber structures in Transylvania

Assessment of structural members and structures

16,15 – 16,45 H.Cruz (Portugal), What one needs to know for the safety assessment of timber structures. Is there a need for guidelines?

16,45 – 17,15 M. Riggio (Italy) Recommendations for nondestructive testing of structural timber: the activity of the RILEM TC 215-AST”

17,15 – 17,45 J. Saporiti Machado, (Portugal) “Strength assessment of old timber structural members. Strategy proposed within the framework of a National project”.

17,45 – 18,15 C.Colla,(Italy) “Diagnosis of structural beams from Cultural Heritage roofs: experimental comparison of sonic tomography and drilling penetration resistance.”

18,15-18,45 P. Palma (Portugal) Structural performance assessment and repair of carpentry joints

Friday May 22, 2009

Structural Typologies and Conservation

09,00 – 09,30 O.Storsletten (Norwey), Roof Construction in the Norvegian Stave Churches: Structural Typologies and Maintenance

09,30 – 10,00 M. Tanac Zeren (Turkey), Structural Typologies and classic costruction details of timber structures “case study – traditional Turkish Houses”

10,00 – 10,30 O.Yilmaz Karaman (Turkey) Importance and conservation of timber elements of structural system within masonry buildings

10,30 – 11,00 V. Rodriguez (Spain) Architectural and structural comparisment of South American and European timber frame structures

11,30 – 12,00 H. Diskaya (Turkey) Types of firewall settlement and structural properties of traditional timber houses in Istambul

Intervention and restoration: cases studies and guidelines

12,00 – 12,45 G.Tampone (Italy) Metodologies and techiniques of intervention

14,00 – 14,45 C.Bertolini Cestari (Italy) Timber roof structures of historical interest: survey methodologies and proposals of interventions. Case-studies.

14,45- 15,30 M.Togni, L.Uzielli (Italy) Assessment and conservation of old timber structures in the Italian Standards

15,30 – 16,00 Posters

16,00 – 17,00 Final discussion and closure of the meeting (Chair H.Cruz (Portugal)).