34 years and counting: The so far experience of World Heritage assets in Thessaloniki, Greece

Situated in the north of Greece, Thessaloniki, the country’s second largest city, is foremostly admired for its uninterrupted history of over twenty-three centuries. In solid proof of this remarkable continuity, its historic center is interspersed with a wide array of archaeological and architectural remains that date from Hellenistic to modern times. The most distinguished segment of this unique heritage is by far the city’s Early Christian and Byzantine legacy. More than half of its surrounding walls, fourteen churches and one bath comprise a unique ensemble, revered in the whole of Europe as early as the 19th century. Not surprisingly, at the end of the 20th century, it became one of the first Greek cultural assets to be inscribed on the UNESCO World Heritage List, Thirty-four years have passed since then, a substantial period of time that allows, on the present occasion of the 50th anniversary of the World Heritage Convention, for a review and appraisal of the impact of the inscription. This is precisely the goal of this paper, which will be pursued through an original discussion and evaluation of the consequences of World Heritage status, on one hand for the monuments themselves, and on the other, for their urban, architectural, social and educational setting. Extensive bibliographic research and thorough on-site examination will provide the basis for this discussion, which will culminate with a didactic conclusion as to the degree to which the full potential of the inscription has been achieved or remains to be pursued

Life Cycle Assessment of a Steel-Framed Residential Building

One of the most widely acknowledged policies, which is also strongly promoted by legislation and government officials globally, is sustainable development. Since the introduction of the term and the development of its content, the movement for sustainable development has been accepted by all business sectors as a set of principles that have to be incorporated into standard practice. Particularly in the case of business sectors such as construction that have been identified as the largest consumers of raw materials and energy there has been considerable pressure to optimize processes in terms of sustainability, with particular emphasis on the environmental impact caused. Steel structures constitute a construction technology which holds significant potential in terms of sustainability. The purpose of the current research is to quantify this potential by calculating the environmental impact caused throughout the life cycle of a steel-framed residential building. A life cycle assessment is conducted, taking into account issues such as raw material acquisition, construction and waste management. The results obtained are used to draw conclusions regarding the application of the life cycle assessment methodology to steel buildings and the environmental data required. Furthermore, observations regarding the quantification of the environmental impact caused by the steel-framed residential building and the identification of the most environmentally damaging processes in regard to the life cycle of the building are also made

Environmental Impact Assessment of the Life Cycle of a Timber Building

Timber construction offers a number of advantages in terms of sustainability in comparison with other construction technologies. This can partly be attributed to the fact that structural timber products often require less processing for their manufacturing compared to other construction products and their sustainability is therefore relatively increased. As a result, structures such as timber buildings are associated with increased sustainability potential and are therefore selected as sustainable solutions for the construction of housing, commercial or other types of building projects. The current research, described in this paper, is aimed at the quantification of the environmental impact caused by the construction of timber buildings. A case study is used as the basis for the calculations which take into account the whole life cycle of the timber building examined. A life cycle assessment is conducted and the environmental impact assessment results are calculated according to the Eco-Indicator 99 methodology. The interpretation of the results leads to conclusions regarding the level and type of environmental impact caused by the life cycle of timber building projects

An intricate encounter? Cultural significance and accessibility in the conservation of the 19th and 20th century monuments of Thessaloniki, Greece

Located in the north of Greece, the city of Thessaloniki encompasses approximately 320 monuments of the 19th and 20th century. Addressed under Greek law as “modern” monuments, most of them were conserved over the past 40 years, with little if any attention to the issue of adaptation to accessibility needs in the initial conservation works. Nonetheless, in more recent projects, specific care was displayed, largely through interventions aiming to facilitate physical access, with two cases of people with disabilities in mind, namely users of wheelchairs and people with restricted mobility. In each of these interventions, two special issues arise: on one hand, the extent to which the safeguard of cultural significance has placed limits on the pursuit of accessibility, and on the other, the degree to which the initiatives undertaken for accessibility have affected cultural significance. Based on extensive on-site research and genuine evaluation, this paper seeks to provide a complete picture and didactic appraisal of this two-way relation. To this end, it undertakes a thorough analysis and assessment of the interventions completed in the so far three main directions of action for accessibility improvement in the “modern” monuments of Thessaloniki: (1) Establishing an entrance, (2) Providing unobstructed horizontal circulation, and (3) Ensuring smooth vertical movement. This analysis allows for a clear answer to be given to the question posed in the title, in addition to revealing prospects for the enhancement of the encounter of cultural significance and accessibility in the most sizable segment of Thessaloniki’s architectural heritage.Located in the north of Greece, the city of Thessaloniki encompasses approximately 320 monuments of the 19th and 20th century. Addressed under Greek law as “modern” monuments, most of them were conserved over the past 40 years, with little if any attention to the issue of adaptation to accessibility needs in the initial conservation works. Nonetheless, in more recent projects, specific care was displayed, largely through interventions aiming to facilitate physical access, with two cases of people with disabilities in mind, namely users of wheelchairs and people with restricted mobility. In each of these interventions, two special issues arise: on one hand, the extent to which the safeguard of cultural significance has placed limits on the pursuit of accessibility, and on the other, the degree to which the initiatives undertaken for accessibility have affected cultural significance. Based on extensive on-site research and genuine evaluation, this paper seeks to provide a complete picture and didactic appraisal of this two-way relation. To this end, it undertakes a thorough analysis and assessment of the interventions completed in the so far three main directions of action for accessibility improvement in the “modern” monuments of Thessaloniki: (1) Establishing an entrance, (2) Providing unobstructed horizontal circulation, and (3) Ensuring smooth vertical movement. This analysis allows for a clear answer to be given to the question posed in the title, in addition to revealing prospects for the enhancement of the encounter of cultural significance and accessibility in the most sizable segment of Thessaloniki’s architectural heritage

Criteria and methodologies for the environmental sustainability assessment of metal structures

The current PhD thesis belongs to a subject area that includes both the field of construction and in particular metal constructions and also the assessment of environmental sustainability. The goals that were set concern the adjusting of the design and construction processes for metal structures to the recently outlined requirements to ensure environmental sustainability within the framework of sustainable development promoted on a European and international level. After conducting research on the principles and the content of sustainable development (Chapter 1), the relevant concepts are examined, along with their evolution and meaning for metal structures. The examination of existing environmental sustainability assessment methodologies allows for the selection of the appropriate one for the case of metal structures, which was found to be Life Cycle Assessment (LCA). The application of this methodology to a simple metal building highlights the issues that have to be researched in order to ensure the reliable and efficient use of the methodology for metal structures. In Chapter 2 research focuses on one of the critical issues in regard to the efficiency of LCA, namely the Life Cycle Inventory (LCI) data. The validity of LCI data directly affects the results of the methodology and as they are currently not available for steel structural elements, primary data is collected for the development of a new LCI database which concerns the steel structural members used in structures. Hot-rolled sections (IPE, HEA etc.) are selected as the starting point and a detailed documentation of the manufacturing processes in terms of environmental impacts caused is conducted. In order to verify the validity of the developed LCI database and the included environmental data and also to gain complete perspective on the range of its application in LCA studies, a comparative study is conducted (Chapter 3) with a number of existing databases which contain some similar data. In Chapter 4 the complementary research which led to the extension of the LCI database to also include cold-formed hollow structural steel members (sections SHS, RHS etc.) is presented. Furthermore (Chapter 5), the data referring to the complete range of acquisition routes of the steel structural members used in Greece are examined and documented. As a result, LCI datasets referring to the steel structural members imported from abroad and also those processed from imported semi-finished steel products are added to the newly developed database. Connection elements used for steel members are also examined, namely steel plates and bolts. The end-of-life scenarios that can be applied to steel building projects are examined in Chapter 6 and the respective environmental impacts for each scenario are calculated and compared. In Chapter 7 LCA studies of four existing steel building projects are conducted, based on the data of the developed LCI database and the end scenarios analyzed. The results obtained, as well as their comparison (Chapter 8), lead for the first time to the quantification of the influence of certain significant parameters on LCA studies. For the facilitation of the management of the LCA data contained in the developed LCI database a software tool was designed (Chapter 9), which also allows for the direct LCA studies of metal building structures. The last chapter of the thesis (10th) contains the most notable conclusions drawn from the research conducted.Η παρούσα διδακτορική διατριβή ανήκει σε μία θεματική ενότητα που περιέχει τόσο τον κλάδο των κατασκευών και συγκεκριμένα τις μεταλλικές κατασκευές, όσο και την αποτίμηση της περιβαλλοντικής αειφορίας. Οι στόχοι που τέθηκαν αφορούν την προσαρμογή των διαδικασιών σχεδιασμού και κατασκευής των μεταλλικών κτιριακών έργων στις προσφάτως καθορισμένες απαιτήσεις για εξασφάλιση περιβαλλοντικής αειφορίας στο πλαίσιο της βιώσιμης ανάπτυξης που προωθείται σε ευρωπαϊκό και διεθνές επίπεδο. Κατόπιν έρευνας σχετικά με τις αρχές και το περιεχόμενο της βιώσιμης ανάπτυξης (Κεφάλαιο 1) εξετάζονται οι σχετικές έννοιες, η εξέλιξή τους και η σημασία τους για τις μεταλλικές κατασκευές. Η εξέταση των υφιστάμενων μεθοδολογιών αποτίμησης της περιβαλλοντικής αειφορίας επιτρέπει την επιλογή της κατάλληλης μεθόδου για την περίπτωση των μεταλλικών κατασκευών, η οποία είναι η μέθοδος Αξιολόγησης Κύκλου Ζωής (LCA, Life Cycle Assessment). Η εφαρμογή της μεθόδου σε μια απλή μεταλλική κτιριακή κατασκευή αναδεικνύει τα σημεία όπου απαιτείται έρευνα προκειμένου να εξασφαλιστεί η αξιόπιστη και αποτελεσματική χρήση της μεθόδου στις μεταλλικές κατασκευές. Στο Κεφάλαιο 2 η έρευνα εστιάζει σε ένα από τα κρίσιμα θέματα που αφορούν την αποτελεσματικότητα της μεθόδου LCA, τα περιβαλλοντικά δεδομένα Καταγραφής Κύκλου Ζωής (Life Cycle Inventory, LCI). Η εγκυρότητα των δεδομένων LCI επηρεάζει άμεσα τα αποτελέσματα της μεθόδου και καθώς τα τελευταία δεν διατίθενται για μεταλλικά δομικά στοιχεία, συλλέγονται πρωτογενή στοιχεία για τη δημιουργία μιας νέας βιβλιοθήκης περιβαλλοντικών δεδομένων LCI που αφορούν τα μεταλλικά δομικά στοιχεία που χρησιμοποιούνται στις κατασκευές. Ως σημείο εκκίνησης επιλέγονται οι διατομές θερμής έλασης (IPE, HEA κτλ.) για τα οποία γίνεται λεπτομερής καταγραφή των διαδικασιών παραγωγής όσον αφορά στις περιβαλλοντικές επιπτώσεις που προκαλούν. Προκειμένου να ελεγχθεί η αξιοπιστία της βιβλιοθήκης LCI που αναπτύχθηκε και των δεδομένων που περιέχει, καθώς και για να σχηματιστεί μία πλήρη εικόνα σχετικά με το εύρος εφαρμογής της στις μελέτες Κύκλου Ζωής διεξάγεται συγκριτική μελέτη (Κεφάλαιο 3) με άλλες υφιστάμενες βιβλιοθήκες LCI που περιέχουν ορισμένα παρόμοια δεδομένα. Στο Κεφάλαιο 4 παρατίθεται η συμπληρωματική έρευνα που οδήγησε στην επέκταση της βιβλιοθήκης LCI για τα κοίλα χαλύβδινα δομικά στοιχεία ψυχρής διαμόρφωσης (διατομές SHS, RHS κτλ.). Στη συνέχεια (Κεφάλαιο 5) καταγράφονται τα δεδομένα που αφορούν όλες τις πιθανές κατηγορίες προέλευσης των μεταλλικών δομικών στοιχείων που χρησιμοποιούνται στην Ελλάδα. Ως αποτέλεσμα, προστίθενται στην αναπτυχθείσα βιβλιοθήκη δεδομένα LCI που αναφέρονται στα δομικά στοιχεία που εισάγονται από το εξωτερικό και αυτά που προκύπτουν από τη μεταποίηση εισαγμένων ημιτελών προϊόντων. Εξετάζονται επίσης και τα στοιχεία σύνδεσης των μεταλλικών στοιχείων, δηλαδή οι χαλύβδινες πλάκες και οι κοχλίες σύνδεσης. Τα σενάρια τέλους του κύκλου ζωής που μπορούν να εφαρμοστούν στις μεταλλικές κτιριακές κατασκευές εξετάζονται στο Κεφάλαιο 6, ενώ υπολογίζονται και συγκρίνονται οι περιβαλλοντικές επιπτώσεις που προκύπτουν για κάθε σενάριο τέλους. Στο Κεφάλαιο 7 διεξάγονται μελέτες κύκλου ζωής για τέσσερις υφιστάμενες μεταλλικές κτιριακές κατασκευές με βάση τα δεδομένα της βιβλιοθήκης LCI που αναπτύχθηκε και των σεναρίων τέλους που αναλύθηκαν. Τα αποτελέσματα που προκύπτουν, καθώς και η σύγκρισή τους (Κεφάλαιο 8), οδηγούν για πρώτη φορά στην ποσοτικοποίηση της επίδρασης ορισμένων καθοριστικών παραγόντων για τις μελέτες κύκλου ζωής. Για τη διευκόλυνση της διαχείρισης των περιβαλλοντικών δεδομένων LCI που περιέχονται στη βιβλιοθήκη που αναπτύχθηκε σχεδιάστηκε ένα σχετικό λογισμικό εργαλείο (Κεφάλαιο 9), το οποίο επιτρέπει και την άμεση διενέργεια μελέτης κύκλου ζωής για κτιριακές μεταλλικές κατασκευές. Στο τελευταίο κεφάλαιο της διατριβής (10ο) παρουσιάζονται τα σημαντικότερα συμπεράσματα που διεξάγονται από την έρευνα που διεξάχθηκε

Supplément grec 1152

ZYGOMALAS (Théodose). histoire politique de CP. de 1391 à 1578Numérisation effectuée à partir d'un document de substitution.Histoire politique de Constantinople de 1391 à 1578 corrigée et mise en forme par [THÉODOSE ZYGOMALAS] (éd. M. Crusius, Turcograeciae libri octo, Bâle 1584, pp. 1-43)