S.Palaoro ARCH BRIDGES, Design-Construction-Perception University of Trento University of Brescia University of Padova University of Trieste University of Udine Università IUAV di Venezia Stefania Palaoro ARCH BRIDGES Design Î Construction Î Perception Tutors: Enzo Siviero, Airong Chen Cotutors: Bruno Briseghella, Tobia Zordan 2010-2011 S.Palaoro ARCH BRIDGES, Design-Construction-Perception UNIVERSITY OF TRENTO Doctoral School in Civil and Mechanical Structural Systems Engineering 23° Cycle Head of the Doctoral School: Prof. Davide Bigoni Final Examination 8 April 2011 Board of Examiners Prof. Antonio Tralli (University of Ferrara) Prof. Bruno Calderoni (University of Naple) Prof. Mariapaola Gatti (University of Trento) SUMMARY The arch bridges have an historical development, that is rooted in their ancient tradition, yet are also very successful to this day, a rediscovery of the earliest arched forms can be seen in the most recent innovations. After millennia of masonry arch bridges and almost two centuries of relentless development of iron, steel and concrete arch bridges, with different structural schemes and constructive shapes, there was a moment that this type of structure was bound to disappear. The scope of traditional arch bridges, which refers mainly to the ones of small and medium span, was to become the uncontested role of the girder bridges. The reuse and the assertion of the arch bridge has been accompanied by a strong architectural emphasis on their structural design and constructive details. This relation, increasingly important during the design phase between the concept of FORM and of STRUCTURE, has ensured that many new projects link the strong relationship between TRADITION and technological and constructive INNOVATION. SOMMARIO I ponti ad arco uqpq"swgnnk"ejg"rtgugpvcpq"wpÓevoluzione storica che fonda le sue radici nella tradizione più anvkec."oc"cpejg"swgnnk"ejg"tkegxqpq"cnnÓoggi il maggior successo, una riscoperta delle prime forme arcuate che ritornano quasi come una moda ma con nÓkorkgiq"fgnng recenti innovazioni: dopo millenni di ponti ad arco in muratura e quasi due secoli di inarrestabile sviluppo di ponti ad arco in ghisa, di ferro, acciaio e di cemento armato, accompagnato da diversi schemi strutturali e di forme costruttive, sembrava che questa tipologia fosse destinata a scomparire. Infatti il campo tradizionale dei ponti ad arco che si riferiva soprattutto ai ponti di media luce era divenuto oramai dominio incontrastato dei soli ponti a travata. Il riuso e il riaffermarsi del ponte ad arco è stato accompagnato da una forte accentuazione architettonica della loro concezione strutturale e dei loro dettagli costruttivi. Il rapporto sempre più importante in fase progettuale di correlare il concetto di FORMA con quello di STRUTTURA ha fatto in modo che molte nuove qrgtg"fÓctvg"fk"pwqxc"tgcnk¦¦c¦kqpg"wpkuugtq"kp"ufi"kn"hqtvg"tcrrqtvq"vtc"VTCFK¥KQPG" e INNOVAZIONE tecnologica e costruttiva. S.Palaoro ARCH BRIDGES, Design-Construction-Perception ACKNOWLEDGEMENTS First and foremost, I wish to thank my tutor Prof. Enzo Siviero, who gave me the opportunity to carry out this study, giving me the right motivation for my choices and the useful and necessary help needed for my training and my scientific growth. I am grateful to him for his patience and his generosity but also for his enthusiasm, his cultural honesty and his teachings which have left a profound impression on me. I came upon to the theme of bridges for the first time when I met Prof. Siviero during my university career. K"ycu"hcuekpcvgf"d{"vjg"ngevwtgu"kp"ÐVjgqt{"cpf"Fgukip"qh" DtkfiguÑ"at the University of Venice, where the main theme is the relationship between form and structure, a combination that is rare in a school of architecture. The research work started while I was writing the degree thesis that was based on historical and technical studies of Italian motorway infrastructures, paying attention to how the architectural shape of bridges and viaducts evolved over the years depending on the technological and constructive innovations and use of new materials. I learned a lot from him especially regarding the fact that the two apparently remote worlds, one being artistic and the other technical, may overlap with one common goal of creating a good design. Through him I also learned how to communicate by means of a different reality from mine own. He is a very true Master. I also want to thank prof. Airong Chen because not only has he contributed to my work with valuable advice, but showing great generosity he allowed me to stay and do research at Tongji University in Shanghai, where I spent a total of eight months This period of study abroad has allowed me to get in touch with a reality that is completely different from mine own, not only in terms of university life, research and design planning, but even from the human point of view.. He was always ready to listen to me, to advise me, to show me things with new eyes. The conversations I had with the Prof. Chen will forever remain in my heart because not only were they rich in scientific content but also in architectural eqpvgpv0"K"nkmg"vq"fghkpg"jko"cu"cp"ÐctejkvgevÑ"coqpi"gpikpggtu0 A special thanks also goes to Prof. Bruno Briseghella and Prof. Tobia Zordan, always present in their contribution through suggestions and for their constant encouragement and illuminating instruction during all the time of my research. Their scientific background, their diligence and their passion in research and teaching gave me the right incentive to complete this study. Thanks to Michele Culatti who helped me a lot on the landscape perception. S.Palaoro ARCH BRIDGES, Design-Construction-Perception K"ecpÓv"hqtigv"rtqh0"Vwnnkc"Kqtk."for the friendly cooperation that began during the degree thesis and continued throughout the years of my PhD. She passed on her passion of teaching methodology and scientific research on to me, she advised me in every choice and helped me to pursue the right direction in the research. For me, she is a outstanding example to follow. Finally, a particular and huge thanks to my family, whose support and patience allowed me to achieve my objective. CONTENTS INTRODUCTION ...................................................................................................... 03 CHAPTER 1: DESIGN - What beauty means? ....................................................... 11 1.1 Introduction Relation between bridge shape and construction method through history 1.2 Chinese ancient arch bridges 1.3 Roman period (700 B.D. Î 400 A.D.) 1.4 Middle Ages period (500-1400) 1.5 Renaissance (1300-1500) 1.6 18th century 1.7 19th century 1.8 What beauty means? 1.9 Final considerations CHAPTER 2: PERCEPTION Î Landscape perception ........................................... 53 2.1 Architecture, place and perception 2.2 Gestalt theory and bridges 2.3 Gestalt and the design: arch bridge becomes architecture 2.4 Landscape and its perception CHAPTER 3: STATE OF ART - Arch bridges in the world and in Italy ................... 93 3.1 Introduction 3.2 State of art in the world 3.3 Italian arch bridges 3.4 First Italian arch bridge realizations in 1900 3.5 Italian arch bridges realized after the Second World War 3.6 Contemporary designers: recent concrete realizations 3.7 Italian steel arch bridges 3.8 Final Considerations S.Palaoro ARCH BRIDGES, Design-Construction-Perception CHAPTER 4: CONSTRUCTION - Construction methods ..................................... 153 4.1 Introduction 4.2 Scaffolding construction method, centering 4.3 Melan scaffolding 4.4 Cantilever construction method 4.5 CFST 4.6 Swing method 4.7 New construction methods for small and medium span 4.8 Advantages and disadvantage of the construction methods CONCLUSION ........................................................................................................ 227 REFERENCES ....................................................................................................... 241