Author: I. Giannetti Title: The Italian story of Ferdinando Innocenti’s tubolar scaffolding (1934-64) Title of the monograph: Proceedings of the Fifth International Congress on Construction History Editors: B. Bowen, D. Friedman, T. Leslie, J. Ochsendorf Date of publication: 07/06/201

This paper was published in the framework of SIXXI Research

thanks to funding of ERc AdvAncEd GRAnT 2011 P.I. SERGIo PoRETTI

PROCEEDINGS OF THE FIFTH INTERNATIONAL CONGRESS ON CONSTRUCTION HISTORY

JUNE 2015, CHICAGO, ILLINOIS

Edited by Brian Bowen Donald Friedman Thomas Leslie John Ochsendorf

VOLUME 2

Construction History Society of America

5th International Congress on Construction History Copyright 2015 © by the Construction History Society of America

All rights reserved. These Proceedings may not be reproduced, in whole or in part, in any form without written permission from the Construction History Society of America.

Proceedings of the Fifth International Congress on Construction History edited by Brian Bowen, Donald Friedman, Thomas Leslie, and John Ochsendorf.

ISBN 978-1-329-15031-7

5th International Congress on Construction History FIFTH INTERNATIONAL CONGRESS ON CONSTRUCTION HISTORY June 3rd-7th, 2015, Chicago

ORGANIZING COMMITTEE Executive Committee Brian Bowen Tom Leslie Don Friedman John Ochsendorf Secretary Website Coordinator Melanie Feerst Jennifer Cappeto Local Committee Mary Brush Ken Monroe Mark Kuberski Anne Sullivan Marvin Levine Marci Uihlein Rick Lightburn Rachel Will Patrick McBriarty

SCIENTIFIC COMMITTEE John Ochsendorf, Chair (USA) Franz Graf (Switzerland) Bill Addis (United Kingdom) Lee Gray (USA) Waldemar Affelt (Poland) Alberto Grimoldi (Italy) Martin Bachman (Turkey) Andre Guillerme (France) Jeffrey Beard (USA) Riccardo Gulli (Italy) Antonio Becchi (Germany) Santiago Huerta (Spain) Philippe Bernardi (France) Benjamin Ibarra Sevilla (Mexico) Brian Bowen (USA) Karl-Eugen Kurrer (Germany) Stephen Buonopane (USA) Pierre-Edouard Latouche (Canada) Claes Caldenby (Sweden) Rejean Legault (Canada) James Campbell (United Kingdom) Thomas Leslie (USA) Robert Carvais (France) Marvin J. Levine (USA) Bor-Shuenn Chiou (Taiwan) Werner Lorenz (Germany) Carlos Eduardo Comas (Brazil) Michael Lynch (USA) Margareth Da Silva Pereira (Brazil) Valérie Nègre (France) Malcolm Dunkeld (United Kingdom) Tom F. Peters (Switzerland) Meghan Elliot (USA) Enrique Rabasa (Spain) Daniela Esposito (Italy) Patricia Radelet (Belgium) Sergej Fedorov (Germany) Hermann Schlimme (Italy) Donald Friedman (USA) Jos Tomlow (Germany) Jorge Alberto Galindo Diaz (Colombia) Marci Uihlein (USA) Piotr Gerber (Poland) Sara Wermiel (USA) Fouad Ghomari (Algeria) David Yeomans (United Kingdom) Amparo Graciani (Spain) Denis Zastavni (Belgium)

5th International Congress on Construction History TABLE OF CONTENTS

Brian Bowen Introduction p17

Paper Sessions and Authors P19

Thomas Leslie Keynote: Construction History in Chicago: Why We’re Here P24

Stella Nair Keynote: Master Masons of the High Andes: Tracing Inca P25 and Tiahuanaco Stone Carving Traditions

James Campbell Keynote: Bricks, Books, Cathedrals, and Libraries P26

William Baker Keynote: Frank Lloyd Wright and the Mile High Tower P27

Santiago Huerta Keynote: Construction History: the Building of a Discipline P28

Michael Abrahamson ‘Decent And Suitable’ Modules: The Politics Of Construction v1 p31 Research In HUD’s Operation Breakthrough, 1969-1974

Francesca Albani Prefabrication In Italy After World War II: Zanuso Versus v1 p39 Camus

Alejandra Albuerne and Martin S. Structural Engineering In The Historic Study Of v1 p47 Williams Architectural Remains. The Basilica Of Maxentius: A Case Study

Umut Almac and Zeynep Ahunbay Structural Aspects Of A 16th Century Ottoman Masonry v1 p55 Building: Siyavush Pasha Madrasa

Carla Maria Amici Hidden Iron: High Tech Devices In Roman Imperial v1 p63 Architecture

Wendy Andrews Innovations In English Wallpaper Materials And v1 p71 Manufacture From 1824 To 1938: Evidence From The Cowtan Order Books

Anna Vemer Andrzejewski Educating The Postwar Builder: College Programs For v1 p79 Aspiring Merchant Builders In The United States, 1945-1965

Ronald W. Anthony and Kent S. Diebolt Investigation And Reconstruction Of A Nineteenth Century v1 p87 Wooden Flume Suspended On A Cliff

J. Antuña Gandía Church Roof Shell: A Slender Folded Roof Shell by v1 p95 Eduardo Torroja

Martin Bachmann The Final Act In Ottoman Timber Construction v1 p103

Laura Balboni and P. Corradini The Construction Of Ice Houses In The Aristocratic v1 p113 Residences In The Emilia Countryside

John Barber Constructing Drystone Built Iron Age Broch Towers In v1 p121 Scotland: Initiating A Construction History

Paola Barbera Construction History: A New Point Of View In Italian v1 p131

5th International Congress on Construction History Historiography In The First Half Of The 20th Century

Fausto Barbolini and Luca Guardigli A Brief History Of Active Systems In Solar Architecture v1 p139

Maria Luisa Barelli Stop And Go. Pathways Of Experimentation With Artificial v1 p147 Stone In The Work Of Sergio Jaretti And Elio Luzi (1955-59)

Tiziana Basirico Experimental Technological Solutions in Mixed Structure v1 p155 Buildings Of The ‘50s In Sicily

Jeffrey Beard Construction Of American Slipways And Dry Docks – Far- v1 p163 Reaching Influence Of US Naval Procurement From Gosport #1 (Norfolk, VA) To the Spearin Doctrine (Brooklyn, NY)

Max Johann Beiersdorf Undulating Mud Brick Walls In Ancient Pharaonic Egypt v1 p171

Paul Bell 19th Century Laminated Timber Roofs In England v1 p179

Alessandra Bellicoso The Casa Del Balilla In L’Aquila (1929-1931). Moving v1 p187 Towards An Independent Skeleton In Reinforced Concrete Structures

Eric Bellin The Constructive Turn: On The Evolution Of Detail As A v1 p195 Disciplinary Concept, 1755-1800

Barbara Berger The Gasholder – Shaped By Its Function. The Italian v1 p203 Example

Inge Bertels and Jelena Dobbels Cataloging Contractors Know-How. An Analysis Of Late v1 p211 Nineteenth- And Early Twentieth-Century Library Catalogues Of Belgian Industrial Schools

Antonio Brucculeri Balancing Art And Science: Emmanuel Brune And The v1 p219 Teaching Of Building Construction At The École Des Beaux- Arts In The Early Third Republic

Mary Brush Lessons From The Restoration Of Chicago’s Skyscrapers v1 p229

Alexandrina Buchanan Construction In The Work Of Robert Willis v1 p239

Fritz-Ulrich Buchmann Carl Tuchscherer: 1911-1934 An Innovative German Timber v1 p247 Construction Company

Laura Buchner R. Guastavino Co: Five Decades Of Construction At The v1 p255 Cathedral Church Of Saint John The Divine

David Bueche and Brian Bowen Trestle: A Peculiarly American Structure v1 p267

Dirk Bühler Historical Models Of Civil Engineering In Collections In v1 p275 Augsburg And Munich

Stephen G. Buonopane and Mikhail Evaluation Of August Komendant’s Structural Design Of The v1 p283 Osanov Shells Of The Kimbell Art Museum

Claudia Calabria Geometric And Constructive Rationalization In The v1 p291 Multiribbed Vault: The “Node” As A Critical Issue

Renata Maria Vieira Caldas and Joints Revealing The Essence: The Bombril Factory In Brazil v1 p299 Fernando Moreira

Anthony Caldwell Pharos Lighthouse: An Experimental Archaeological Digital v1 p307

5th International Congress on Construction History Reconstruction

José Calvo-López, Miguel Á. Alonso- Geometry And Capriciousness In 11th-Century Armenian v1 p315 Rodríguez, Enrique Rabasa-Díaz, Ana Architecture. The Scriptorium Of The Monastery Of Sanahin López-Mozo, Carmen Pérez-Ríos, and Pau Natividad-Vivó

Gabriela Campagnol and Stephen Construction Of The Museu De Arte De São Paulo v1 p323 Caffey

Tiziana Campisi and Manfredi Saeli Aristocratic Palaces In The XVIII Century In Palermo The v1 p333 Construction Site Of Merendino Costantino Palace

Stefano Camporeale Concrete Barrel Vaults Reinforced With Stone Voussoirs v1 p341 Arches In The Western Provinces Of The Roman Empire (Mauretania Tingitana And Baetica)

Jennifer Cappeto Best Supporting Actor: The History Of Metal Lath In v1 p351 America

Maria do Carmo Ribeiro and Arnaldo Organization Of Construction Activity In Medieval Portugal: v1 p359 Sousa Melo A Comparative Approach

Caterina F. Carocci and C. Tocci Learning From The Past. Anti-Seismic Techniques in the v1 p367 L’aquila Post-1703 Reconstruction

Caterina F. Carocci Construction History Of The Syracuse’s Lyrical Theatre. v1 p375 Remarks On The Masonry Work In A Second Half Of Nineteen-Century Site.

Robert Carvais and V. Nègre Parisian Surveyors (1690-1792): Founding An Expert Corps v1 p383

Agustín Castillo Martínez The Transpyrenean Railway Via Canfranc v1 p395

Philip Caston The Amazing Mathematical Bridge v1 p403

Miquel Àngel Chamorro Trenado, R. Public Works And The Historical City In 19th-Century Spain: v1 p411 Ripoll Masferrer, and J. Salvat Comas The Isabel II Bridge Of Girona

Michele Chiuini The Construction Of the Chicago Stock Exchange By Adler v1 p419 And Sullivan: Structural System And Typological Innovation

Michael Mark Chrimes Architect Or Engineer? Professional Identity In Public Works v1 p427 In British India 1800-1910

Thierry Ciblac and Mathias Fantin Rediscovering Durand-Claye’s Method Using Force Network v1 p439 Method Implemented For Construction History

Lorenzo Ciccarelli Architecture As Construction In The Beginnings Of Renzo v1 p447 Piano. Five Patents For Construction Systems And “Pieces” Of Buildings (1965-1969)

Ana Teresa Cirigliano Villela and Archaeology Of Architecture: Contributions To The History v1 p455 Regina Andrade Tirello Of Brazilian Construction - Reflections On The Applicability Of “Harris Matrix”

Jonathan Clarke American-Trained Structural Engineers And Contractors In v1 p463 London, 1895-1910

Jørgen Cleemann Early History Of The Concrete Transit Mixer, 1900-1930 v1 p473

5th International Congress on Construction History Quentin Collette and Ine Wouters Unraveling The Design Of End-Of-The-19th-Century v1 p481 Riveted Connections In Belgium

Alessandra Como and L. Smeragliuolo Is Architecture Moving Toward Immutable Forms And v1 p491 Perrotta Characters? An Investigation At The Theoretical Level Of The Thought Of The Italian Engineer Pier Luigi Nervi Through Texts And Images

Sandrine Conan Flat Arches With Joggle Joints: Their Use In Twelfth And v1 p499 Thirteenth Century Cistercian Abbeys

Elizabeth Cook Labor Disputes, Price Gouging, And Ornamental Arches: v1 p507 Negotiating A New Building Culture At The Virginia State Penitentiary

Elizabeth Cook From Susquehanna Pine to North Carolina Cypress: v1 p515 Regional Lumber Supplies in Antebellum Richmond, Virginia

Thomas Coomans and Yitao Xu Gothic Churches In Early 20th-Century China: Adapting v1 p523 Western Building Techniques To Chinese Construction Tradition

Rachel Cruise The 300 Metre Tower v1 p531

Andrew Cruse Are You Comfortable Now? Three American Thermal v1 p539 Comfort Models

Manfred Curbach, Thomas Hänseroth, Genius And Nazi? Willy Gehler (1876−1953) − A German v1 p549 Falk Hensel, Silke Scheerer and Oliver Civil Engineer And Professor Between Technical Excellence Steinbock And Political Entanglements In The 20th Century

Edoardo Currà, Domenico Liberatore, History, Development And Application Of Anti-Seismic v1 p557 Cesira Paolini, Elena Pizzoli and Techniques: The Post-Earthquake Reconstruction Of The Alessandro D’Amico “Pio Monte Della Misericordia” In Ischia

Magdalena Daniel Constructing Health – The Pursuit Of Engineering A “Health- v1 p565 Promoting Interior Climate” During The 1830s And 1840s

Beatriz del Cueto Portland Cements In The Spanish Caribbean As Agents Of v1 p573 Change: Hydraulic Mosaics And Concrete Blocks

Robert Dermody David B. Steinman - Design And Construction Of The v1 p583 Mackinac Bridge

Rika Devos and M. Mollaert A Quest For Early Tensile Structures At Expo 58 v1 p591

Marco di Nallo ‘Construire Mieux, Plus Vite Et Moins Cher’ – Swiss v1 p601 Industrialised School Building Systems

Gemma Domenech Casadevall Protectionism, Corporatism And Endogamy In The Building v1 p611 Guilds Of Catalan Coastal Cities During The Modern

Karey Draper Building For War: Examples Of Temporary Structures v1 p619 Designed For Wartime Use In Britain (1939-1945)

Gregory Dreicer History Of Engineering, Reverse-Engineered v1 p629

Malcolm Dunkeld The Portrait Collection Of The Institution Of Civil Engineers v1 p635

5th International Congress on Construction History Carlo Dusi “Roam Home To A Dome”, From Metaphor To The v1 p645 Construction: Dante Bini’s Pneumatic Formwork Thinshelled Reinforced Concrete Domes

Jonathan Calman Ellowitz and John A. Construction And Demolition History Of Guastavino v2 p31 Ochsendorf Vaulting At The Metropolitan Museum Of Art

Bernard Espion The Founding Events Of Prestressed Concrete In Belgium v2 p41 Seen Through The Blaton Archives

Richard Etlin The “Strength Of Vaults” v2 p49

Sergej Fedorov Early Prefabricated Iron-Ribbed Domes: St. Isaacʼs v2 p61 Cathedral In St. Petersburg, Russia, 1838 –1841

Corentin Fivet, D. Zastavni, and J. A. What Maurice Koechlin’s Scientific Contribution Tells About v2 p71 Ochsendorf, His Life (1856-1946)

François Fleury and Bernard Duprat Analysis Of An Unpublished Treatise Of An 18th Century v2 p79 Engineer, Antoine d’Alleman (1679-1760)

Robert M. Frame III Prestressed Suburbia: A New Material In Postwar v2 p87 Construction

Donald Friedman Above-Ground Archaeology Of Demolished Buildings v2 p95

Anke Fritzsch Innovation And Reception: Historic Heating Systems In v2 p103 European Museum Architecture Of The 1st Half Of The 19th Century

Paula Fuentes and S. Huerta Crossed-Arch Vaults In Late-Gothic And Early Renaissance v2 p111 Vaulting: A Problem In Building Technology Transfer

Roland Fuhrmann The Evolution Of Streamlined Airship Hangars v2 p119

Emmanuelle Gallo Parisian Swimming Pools Of The Nineteenth And Early v2 p127 Twentieth Centuries, Examples Of “Sustainable Development” And Savings

Ricardo García Baño and José Calvo About An Early 16th-Century Stonecutting Manuscript In v2 p135 López The National Library Of Spain And The Origins Of Modern Stereotomy

Rafael García García Spatial Structures In Spain 1950 – 1970, First Experiences v2 p143 Before The Standarized Systems

Julian Garcia Munoz and F. Magdalena Equilibrium And Prefabrication. Prefabricated Brick Vaults v2 p153 Layos In Latin America

Dario Gasparini Whistler, Howe And Stone: The Design And Construction Of v2 p161 The Western Railroad’s Bridge Over The Connecticut River 1840-1841

Ralph Ghoche Towards A Parabolic Architecture: The Parabola As Polemic v2 p169 In Mid-Nineteenth-Century French Architecture

Ilaria Giannetti The Italian Story Of Ferdinando Innocenti’s Tubolar v2 p177 Scaffolding (1934-64)

Ignacio-Javier Gil Crespo Late Medieval Rammed Earth Technique In The v2 p185

5th International Congress on Construction History Fortifications Of Castile, Spain

Javier Giron The “Parallel” and The Comparative Method In Jean v2 p193 Rondelet Traité Théorique Et Pratique De L'art De Bâtir

Daniel R. Gleave, John A. Ochsendorf, History And Technology Of The Timber Structures Of v2 p201 and Emory Kemp Lemuel Chenoweth

Marisa Gomez Defining Modern In Postwar Amarillo: The Schell Munday v2 p211 Co. And The 1947 Perma-Stone Protest

Esperanza Gonzalez-Redondo First Iron Structures In Buildings: A Fireproof Transition v2 p221 Case Study In Madrid

Yves Govaerts, A. Verdonck, W. Development Of Artificial Stone Imitations At The Turn Of v2 p229 Meulebroeck, and M. de Bouw The 20th Century Through Patent Analysis In A Belgian Context

Amparo Graciani Building The Pavilions Of The United States Of America In v2 p237 The Iberian-American Exposition (Seville, 1929)

Franz Graf The Duval Factory At Saint-Dié – Purism In Transition v2 p245 (1948-1950). Notes Towards A Construction Monograph

Lee Gray Lift Versus Elevator v2 p255

Beverly K. Grindstaff Demobilization, Construction, Conversion: American v2 p263 Veterans Housing In The Immediate Post-War Era

André Guillerme First Treaty On The Industrialization Of Barracks (1804- v2 p269 1811)

Liane Hancock Turner City v2 p277

Benjamin Hays The Many Lives Of Thomas Jefferson’s Rotunda v2 p285

Rafael Hernando de La Cuerda The Exhibition And Information Centres In Madrid And v2 p295 Barcelona, The Driving Force Behind Modern Construction In Spain

Catharine Hof Building Conversion As Demanding Task In Late Roman v2 p303 Construction – Adding Vaults To The Towers Of The Sixth Century City Wall Of Resafa, Syria

Christoph Hölz Art And Industry Around 1850. The Civil Engineer Franz v2 p313 Jakob Kreuter

Yasuhiro Honda and Ichiro Kobayashi Comparative Study On The Arch Structure Of The Kintaikyo v2 p321 Bridge And Occidental Timber Arch Bridges

Benjamin Ibarra-Sevilla Unusual Conditions = Novel Solutions: Guastavino’s v2 p329 Strategies And Underlying Geometry For The Vaults Of Irregular Plan In New York Municipal Building

Lukas Ingold and Mario Rinke Sergio Musmeci’s Search For New Forms Of Concrete v2 p339 Structures

Tullia Iori and Sergio Poretti The Language Of Structures. The Italian School Of v2 p347 Engineering

Nigel Isaacs What’s Holding The Roof Up? Using Census Data To v2 p355

5th International Congress on Construction History Explore Dwelling Construction And Structure Changes

Marieke Jaenen, Michael de Bouw, Constructing The Antwerp Interwar Interior: The Significant v2 p363 Ann Verdonck, and Maria Leus Contribution Of Firms

C. Jäger-Klein, G. Radinger, W. Stumpf, The Interrelation Of Structure, Natural Ventilation And v2 p373 and G. Styhler-Aydın Daylight Input In The Historic Architecture Of Jeddah, Saudi-Arabia

Andreas Kahlow Bützow’s Wrought Iron Lattice Truss Bridge Across The v2 p381 Nebel River, 1848: Design, History, And Reconstruction

Yegan Kahya Sayar, Işıl Polat Pekmezci, Construction Techniques And Building Materials Of A 19th v2 p389 and Ayşegül Özer Century Official Structure In Istanbul: Adjacent Offices Of Ottoman Bank And The Regie Company

Kemal Reha Kavas Structural Patterns In The History Of Anatolian Composite v2 p397 Masonry

Stephen J. Kelley, Alan O’Bright, and The Old Courthouse Reveals The Role Of St Louis At The v2 p407 Dan M. Worth Forefront Of Architectural Cast Iron In The United States

Nassiri K. Kiomars, Pouya Foulad, and A Survey Into The Evolution Of Construction Contracts In v2 p415 Mohammad Mehdi Mortaheb, Iran: Two 19th Century Contracts

Daijiro Kitagawa Modernization Of Japanese National Route 1 In 1920’s And v2 p423 1930’s

Sabine Kuban Innovation And Standstill – Early Application And v2 p431 Development Of The “MONIER System” In Berlin

Sabine Kühnast The Development Of New Building Materials In Germany v2 p439 From 1919 Onwards And Their Standardization Using The Example Of Hollow And Perforated Clay Bricks

Stefano Lamborghini, Giovanni Mochi, Historic Timber Trusses In Europe. The Case Of St. Peter In v2 p449 Luca Venturi, and Luca Guardigli Bologna

Lynne Lancaster “Armchair” Voussoir Vaults In Bath Buildings Of The v2 p457 Western Roman Empire

Marvin Levine Building In Chicago: The Story Of Builders And Contractors v2 p465 Over The Last 100 Years

Marvin Levine Getting Paid: How U.S. Builders And General Contractors v2 p473 Fought To Get Paid When Disputes Arose On Their Projects, 1890-1990

Yan Liu The Invention Of Da Vinci’s Woven Structures v2 p481

Fabián S. López Ulloa The Archaeological Drawings Of G. E. Street, A Resource v2 p489 For Understanding Spanish Gothic Architecture

Ana López-Mozo, Rosa Senent- Asymmetrical Vaults In Late European Gothic: Basel And v2 p497 Domínguez, Miguel Ángel Alonso- Bebenhausen As Case Studies Rodríguez, José Calvo-López, and Pau Natividad-Vivó

Werner Lorenz and Bernhard Heres The Demidov Ironworks In Nevyansk (Ural Mountains) – v2 p505 Iron Structures In Building From The First Half Of The 18th

5th International Congress on Construction History Century

Hentie Louw A Question Of Identity: Evolving Relations Between The v2 p517 English Carpenters And Joiners From The Mid-Sixteenth To The Early-Twentieth Century

Michiko Maejima A Study Of Military Facility Planning From The Viewpoint v2 p525 Of Technological Transfer From France To Japan 1868‐1930

Rocio Maira Vidal The Construction Of Sexpartite Vaults In Europe v2 p533

Julia Mathias Manglitz and K. Vance Cleverly Concealed: The Truth Behind Victorian Era Butter v2 p541 Kelley Joint Running Bond

Rafael Martin Talaverano Knowledge Exchange For The Design And Construction Of v2 p549 Surbased Ribbed Vaults

Roland May Shell Sellers, The International Dissemination Of The Zeiss- v2 p557 Dywidag System, 1923–1939

Leah McCurdy Maya Construction History: Explorations Through Buildings v2 p565 Archaeology And Conservation

Sarah Melsens and Inge Bertels Shaping India’s Cities The Changing Role Of Stakeholders In v2 p575 Construction Since Independence (1947)

Marina Anna Laura Mengali The Construction Of The First Curtain Wall Of Viterbo In v2 p583 1095 A. D.: A Modern Example Of Standardization And Organization Of A Complex Fortification Work

David Miranowski and Brandon Clifford Re-Learning Sigurd Lewerentz: An Applied History Of The v2 p591 Church Of St. Peter’s In Klippan, Sweden

Eberhard Möller Invention And Innovation In Structural Design And v2 p599 Construction – Frei Otto And The Munich Olympic Stadium 1972 – A Historical Case Study

Eric Monin The Discreet Efficiency Of “IN-BILT” Prismatic Glass v2 p607 Lighting Systems

Mónica Morales-Segura Analysis On The Roof Of The Sanctuary Of Our Lady Of v2 p617 Guadalupe, In Madrid (SPAIN). Clarifications On The Participation Of Felix Candela In The Project

Renato Morganti, A. Tosone, D. Franchi Steel Construction For A New Public Company. The Rai v2 p625 and D. Di Donato Executive Offices

Renato Morganti, A. Tosone, S. Cocco, Patents Of Anti-Seismic Structures In Iron And Steel. 1908, v2 p633 and D. Di Donato Messina Earthquake – 1957, International Classification Of Europe Council

Mahdi Motamedmanesh and Klaus Form Follows Construction: A Technical Analysis Of The v3 p31 Rückert Arch Of Ctesiphon, The Widest Ever Built Adobe Vault

Jane Murphy Norman Cherner And DIY After World War II v3 p41

Jane Murphy Federally Funded Research And The Small Homes Council v3 p49

Ivan Myjer A Comparison Of The Construction Technology Of Three v3 p57 18th Century Spanish Colonial Mission Churches In San

5th International Congress on Construction History Antonio, Texas

Ekaterina Nozhova Assembled Without Scaffolding: The Construction Of v3 p67 Schukhov’s Timber Lattice Hyperboloids

Hilal Tuğba Ormecioglu, Bilge Bridging The Golden Horn: A Challenge Of Engineering, v3 p75 Kucukdogan, and Aslı Er Akan Architecture, And Technology At The Turn Of The Century

José Carlos Palacios Gonzalo and Fabio Inclined Keystones In Spanish Late Gothic v3 p83 Tellia

Gabriel Pardo Redondo and Berta de Perception Of The Tower Building – New York 1889 v3 p93 Miguel Alcalá

Jacob Paskins Constructing The Hoverport: Building Hope, Raising Fear v3 p99

Eberhard Pelke and Karl-Eugen Kurrer On The Evolution Of Steel-Concrete Composite Construction v3 p107

Tom F. Peters Religious Affiliation And Wooden Truss Construction In The v3 p117 German-Speaking World

J. William Plunkett and Caitlin T. Thin Concrete Shells At Mit: Kresge Auditorium And The v3 p127 Mueller 1954 Conference

Giorgia Predari, G. Mochi, and Riccardo Historical Construction In The 30’S: The Case Study Of The v3 p137 Gulli Faculty Of Engineering In Bologna, Italy

Wido Quist J.A. Van Der Kloes (1845-1935). A Professional Biography v3 p145 Of The First Dutch Professor In Building Materials

Patricia Radelet-DeGrave The Catenary As Inspiration v3 p153

Christoph Rauhut Bauplatzstatik – How Structural Theory Altered Average v3 p163 Building Processes And How Daily Routine Influenced Structural Analysis

William E. Reifsteck II Two Million Bricks In 160 Days: The Construction Of Notre v3 p171 Dame Stadium In 1930

Roberto Reyes Pérez, Lucía Tello Peón The Yucatecan Hacienda: Relations Between Production v3 p179 and Pablo A. Chico Ponce de León Systems, Construction Processes, Materials, And Settlements Morphology

Elsa Ricaud Pre-Columbian And Early Colonial Adobe Bricks In The v3 p187 United States: A Tool In The Service Of Dating Historic Buildings

Mario Rinke Terner & Chopard And The New Timber – Early v3 p197 Development And Application Of Laminated Timber In Switzerland

Sage M. Roberts and Brian Bowen The Amundsen-Scott South Pole Station: Construction At v3 p205 The End Of The World

Ana Rodríguez García Thinking With The Eye, Thinking With The Hand; Looking v3 p213 For A Modern Construction Between Industry And Craftsmanship: The Upper Lawn Pavilion By Alison And Peter Smithson 1959-1962

Christine Roels Literature Review On Rural Architecture In Belgium: Ideas v3 p221

5th International Congress on Construction History To Modernize Farmsteads In Architectural Publications From 1847-1884

Abe Yillah Roman Alvarado Historical And Constructive Aspects Of The Iron Municipal v3 p229 Palace At Orizaba In The Nineteenth-Century

Marco Rosario Nobile and E. Garofalo Stereotomy Of The Late-Medieval Mediterranean. v3 p239 Crossroads Of Experimental Design

Giulio Sampaoli Electric Lighting In The Architecture Of Le Corbusier: v3 p247 Towards A History Of Technical Installations

Hermann Schlimme Western Style Spring Fountains, Plays Of Water And v3 p255 Hydraulic Construction In The Yuanmingyuan In Beijing And Their European Models

Rosa Senent-Domínguez, Ana López- Late Gothic Ribbed Vaults. Basis For Cataloging v3 p265 Mozo, Rafael Martín-Talaverano, Carmen Pérez-de-los-Ríos and Enrique Rabasa-Díaz

Anna Serafini and Cristina González- The Design And Construction Techniques Of Eighteenth v3 p273 Longo Century Timber Roofs In Scotland: Glasgow Trades Hall and Tweeddale House In Edinburgh

Barbara Shapiro Comte King’s Feet To Republican Metres: The Evolution Of v3 p281 Construction Drawings, Paris, 1782-1876

Elizabeth Shotton The Divergence Of The Professions: James Gandon, John v3 p293 Rennie And The Building Of The Revenue Docks

Elizabeth Shotton The Evolution Of The Iron Truss In The Work Of John v3 p303 Rennie

Changxue Shu From The Blue To The Red: Changing Technology In The v3 p313 Brick Industry Of Modern Shanghai

Monica Silva-Contreras The Guastavino System In Mexico: Rescuing The Unknown v3 p321 Work Of A Modern Builder

Nathalie Simonnot Architecture And Construction In Artificial Lighting Us And v3 p329 French Journals (1928-1939)

Marina Šimunić Buršić Problems Of Vaulting The Eastern Part Of The Gothic v3 p337 Cathedral Of Zagreb (Croatia)

Stéphane Sire and Jean-François The Electric Arc Welding Reinforcement Of Steel Bridges v3 p345 Douroux From The Paris Metro In The 1930s: The Case Of The Austerlitz Viaduct Over The Seine

John Smallwood A Historical Review Of Construction Health And Safety v3 p355

Funda Solmaz Şakar, and Neriman Traditional Structural Elements In Ürgüp: Walls And Vaults v3 p363 Şahin Güçhan

Tyler Sprague The Rise Of The Exterior Bearing Wall, Or “Tube”, v3 p371 Skyscraper: An Alternative Perspective From Seattle

Tyler Sprague Sculpture On A Grand Scale: The Structural Geometry Of v3 p379 Jack Christiansen’s Thin Shells

5th International Congress on Construction History Knut Stegmann Experimental Cultures In Early Concrete Construction v3 p387

Alicia L Svenson Building Harvard Stadium: Early Concrete Design And v3 p395 Construction

Robert Svetz Atrium (W)HOLES In The Code v3 p403

Naoto Tanaka Study On History Of Community Development Based Water v3 p413 Use In Minamiaso, Kumamoto

Chiara Tardini Brenner Railway Bridges: The Diffusion Of Howe Typology v3 p421 In Austrian Empire

Isabel Tarrío The Buttressing System In Pol Abraham’s Criticism Of v3 p429 Viollet-Le-Duc’s Theories

Luis A. Torres-Garibay and Eugenia M. Purépecha Work Organization In Traditional Architecture v3 p437 Azevedo-Salomao Production

Ana Tostões Learning From An Outstanding Process. The Gulbenkian v3 p445 Foundation Buildings (1959-1969)

Klaus Tragbar Constructing A Cathedral. Notes On The Construction v3 p455 Management Of Siena Cathedral

Kanokwan Trakulyingcharoen Alfredo Cottrau And Iron Lattice Bridge Construction In v3 p465 Italy 1860-1887

Michael Tutton Staircases In Early Eastern Keeps In England C1067 To v3 p473 C1190 With Particular Reference To Rochester

Michael Tutton A Brief Introduction To Tread And Hand Wheel Cranes And v3 p481 Hoists In Construction As Depicted In Western Art

Marci S. Uihlein American Institute Of Consulting Engineers And The v3 p491 Professionalization Of The American Engineer

Petra Urbanova and Pierre Guibert New Insights Into The Dating Of Roman And Medieval v3 p499 Mortars By Optically Stimulated Luminescence [OSL]: Comparison Of Case Studies

Wiepke van Aaken and Andreas W. Putz “Not The Fault Of The Material, But Of Our Attitude” – v3 p509 Insulation Materials In Switzerland From 1950 To 1970

Stephanie Van de Voorde Thermal Insulation In Belgium Before The First Oil Crisis v3 p517 (1945-1975). A Question Of Economy And Comfort?

Hernando Vargas Caicedo and Jorge The Construction Of Thin Concrete Shell Roofs In Colombia v3 p525 Galindo Díaz During The First Half Of The 20th Century: The Works Of The Guillermo González Zuleta (1916-1995)

Niklas Vigener, Nicholas T. Floyd, and A Flood Of Light – The Case For Daylight In American v3 p535 James Jamieson Public Architecture

Camilo Villate and Brando Tamayo Technical Innovations In Bogota´s Modern Times – The Pan v3 p545 American Life Insurance Building (1966) Case Study

Neal Vogel The History And Conservation Of Lead Silhouettes In v3 p553 America

Kenji Watanabe and W. Mikishi Abe: Japanese Pioneer Engineer-Architect Of v3 p561

5th International Congress on Construction History Abhichartvorapan Reinforced Concrete In The Early 20th Century

Christiane Weber The Last Witnesses – Physical Models In Architecture And v3 p569 Structural Design, Taking The Technical University In Stuttgart As An Example

Sean Weiss Frozen Assets: Photography, Time, And Labor On The v3 p577 Construction Site

Volker Wetzk The Use Of Steel Castings In Mechanical And Civil v3 p585 Engineering – Germany. 1850-1950

Rob Whitehead Formative Experiences: Saarinen’s Shells And The v3 p593 Evolutionary Impact Of Construction Challenges

Rachel L. Will and Edward A. Gerns Detailing In Transition: Hybrid Walls And The Evolution Of v3 p603 Terra Cotta Detailing

Elke Katharina Wittich “Architecture Is Construction” – Term And Definition In v3 p613 German Architectural Writing In The Early 19th Century

Ine Wouters and I. Bertels Building With Bookcases: An Archive Depot In Iron v3 p621 (Antwerp, 1851)

Emanuele Zamperini Timber Trusses In Italy: The Progressive Prevailing Of v3 p629 Open-Joint Over Closed-Joint Trusses

Denis Zastavni and C. Fivet Purely Geometrical Considerations During The Design Of v3 p637 Bridges In The Early 20th Century – The Case Of R. Maillart

John Zils Construction Of Willis (Sears) Tower v3 p645

Author Index v1 p653, v2 p641, v3 p655

5th International Congress on Construction History 5th International Congress on Construction History INTRODUCTION

These Proceedings in three volumes record the papers presented at the 5th International Con - gress on Construction History held in Chicago in June 2015. This conference follows four suc - cessful international congresses held previously: Madrid (2003), Cambridge UK (2006), Cottbus (2009), and Paris (2012). Following trends set in the previous Congresses, the breadth and scope of the subjects ad - dressed continues to be extraordinary. The topics cover the history of construction in every era, of buildings and civil works, their engineering and architecture and of the processes and organiz - ation used to build. This demonstrates the value of examining our industry’s past in a compre - hensive manner in order to inform the future. We have not attempted to sort the papers into broad categories. However a listing of the or - ganization of papers into sessions that was used at the Congress is included as a guide. The pa - pers are presented here in alphabetical order by the first author’s family name. The table of con - tents provides all of the paper titles and the index lists all authors.

5th International Congress on Construction History

THE ITALIAN STORY OF FERDINANDO INNOCENTI’S TUBOLAR SCAFFOLDING (1934-64)

Ilaria Giannetti1

Keywords

History of the specific builders, History and construction of specific projects, Development of construction tools and scaffolding

Abstract

How were realized the reinforced concrete works of Italian structural art in the dimension of the handcrafted construction site? The construction process of the arch bridges of the Autosole or the Pier Luigi Nervi’s Palasport domes based its challenge on a unique construction tool: the In- nocenti tubular scaffolding. Deus ex machina of this revolutionary construction tool was Ferdinando Innocenti, a black- smith who, grew up in the paternal laboratory, patented in 1934 a revolutionary “device for unit- ing tubes of metallic structures”, consisting of a clamping bolt with a T-shape head and a hinge. Of rapid assembly, portable, reusable and much more cost-effective than traditional timber fram- ing, the system immediately established itself on the national building and still outstands among the steel products manufactured in Italy. In the Thirties, it was applied to reinforced concrete construction projects, to set up imposing, temporary works to suit the needs for Fascist propaganda, and also for military use. In post-war years, following the establishment of a new company (Ponteggi Tubolari Dalmine Innocenti) founded by a team of structural engineers, the system was used in the construction of awe- inspiring, dismountable and portable steel tube scaffolds designed to support viaducts connecting the new motorways. In 1958, the transfer of the scaffold to be applied to the construction of the twin arch bridge across the Aglio river along the Autostrada del Sole was a pioneering technolo- gy performance. During the same months, even Pier Luigi Nervi used the pipe joint system to combine the precast and cast-in place components of his Palasport domes. In the 60’s, as the system had risen fast on international scene, construction gradually turned to more standardised solutions. Between 1961 and 1963, the pipe joint system was used in the construction of the last arch bridges connecting the Autostrada del Sole in the Florence-Rome. That anticipated also the end of the cast-in place, reinforced concrete arch era and the dissolution of the distinguishing features of the Italian construction site that had been represented by Ferdi- nando Innocenti’s creation. The survey is conducted within the research project “SIXXI - 20th Century Structural Engi- neering: the Italian contribution”, aimed to trace the “material history” of structural engineering in Italy (Iori, Poretti, 2014).

1 University of Rome “Tor Vergata”, SIXXI project (www.sixxi.eu), via del Politecnico 1, 00133, Rome [email protected]

5th International Congress on Construction History The Italian story of Ferdinando Innocenti’s tubolar scaffolding (1934-64)

Figure 1: Ferdinando (1936); Innocenti centering, Orba bridge (1935); Innocenti centering, Biscione viaduct (1958) In August 1935, an unconventional scaffold was used in the construction of a cast-in place reinforced arch bridge spanning 50 m across the Orba river. That was the first steel tube scaffold ever build in Italy. It was designed and constructed by the Milan-based company Fratelli Inno- centi. The centering, counting 5747 linear metres of small-diameter (48 mm) Dalmine tubes and 4590 steel couplers, amazed the engineers for its excellent static performance compared to the remarkably fast set-up and a clear economic advantages compared to traditional timber framing. The system became the topic of a number of scientific memories and quickly spread on the national building trade. It was the first site of the bacillus tubularis that, became widespread in the post war years, was to become a part of the “craftsmanship” of the structural masterpieces of Italian engineering of the boom years.

The Innocenti coupler (1934)

On 6 February 1934, the Fratelli Innocenti company applied for the first patent for a “device for uniting tubes of metallic structures”. The invention was the result of the quick wit of Ferdinando Innocenti, the company’s owner, as a development of the British and American clamp model, which had been tested in the first few years of the century in an attempt to replace wooden scaffolding for casting reinforced con- crete constructions with a more versatile and affordable metal structure. The coupler consisted of two hinged “hats” and a “core”, producing the friction to clamp two perpendicular tubes, and it was featured with a revolutionary opening and clamping device. Made up of two “T hinge-bolts”, the new device had lower production costs and, during assem- bly, the two “hats” could be held together when being opened to grip the tube. The clamp was, therefore, very inexpensive and, above all, fast and intuitive to use. Compared with other systems used at the time, the invention was immediate successful. In just over a year, the tube and coupler system became widely used in reinforced concrete building sites and became the key player of unique constructions.

5th International Congress on Construction History I. Giannetti

Figure 2: Ferdinando Innocenti – F.lli Innocenti, patent 328448 (1934), patent 388780 (1936), patent 358334 (1938) In early 1934, Innocenti won the tender to install fire protection systems in the Sistine Chap- el, and their quick and easy-to-assemble scaffolding proved to be able to avoid damage to its precious frescoes. During the summer of the same year, the tube scaffoldings made it possible to quickly carry out the stadium expansion plan promised to the public by Mussolini for the World Soccer Cup to be hosted by Italy. By the end of the 1930s, the tube and coupler, improved by further patents, was in common use in construction sites throughout Italy and gradually began to replace traditional wood car- pentry, even for the more structurally-challenging works. Even when restrictions on the use of iron, imposed by autarchic policy, meant that large rein- forced concrete constructions were put on hold, use of the system remained steady.

Propaganda and war

On 1 December 1936, the coupler reached the United States, and whilst the patent spread be- yond national borders, the steel tube structures proved to be very suitable for military use and for creating the urban settings of fascist propaganda. In early 1935, Innocenti was directly involved in preparing for the military campaign in Ethiopia by designing a type of collapsible tube-based hangar, as an emergency shelter for air force units, and a portable military bridge, a lattice girder made up of tubes. In Rome, between 1937 and 1940, a gigantic M-shaped tubular “Arc de Tri- omphe” hailed Mussolini’s return from Germany and high tubular towers were the landmarks of exhibition events. Indeed, the temporary pavilion of the Roma Ostiense railway station, a grandi- ose cardboard backdrop for Hitler’s visit to Rome, was built in the sumptuous “Stile Littorio” in just 45 days thanks to the fast assembly provided by the Innocenti system. The excellent perfor- mance of the tubes for propaganda brought Innocenti closer to prominent figures of the Regime. On 26 November 1939, Ferdinando was appointed “Cavaliere del Lavoro” for the “ingenious use of tube scaffolding in building construction (...), now widespread throughout Italy, a system which has solved a major problem”. On 14 February 1940, a toy model of Innocenti’s tubing was delivered to Villa Torlonia for the Duce’s children. Generously offered by Ferdinando, the gift sealed the agreement between Innocenti and Mussolini leading to the company’s front-line in- volvement in the arms production plans. During the war, productivity in Milan’s factories re- mained extremely high with over 7000 workers building weapons and ammunition.

5th International Congress on Construction History The Italian story of Ferdinando Innocenti’s tubolar scaffolding (1934-64)

Figure 3: Innocenti tower, Milan (1933); PNF Stadium, Rome (1933); Innocenti “Arc de Triomphe”, Rome (1940) Reconstruction

Only in 1945, immediately after the war, did Fernando gain new interest in the construction tubes. Intrigued by the debate on building industrialisation, which emerged during the post war reconstruction struggle, on 3 August 1945, he filed a patent for a “coupler for fixing metal form- work to tubular scaffolding supports”. While retaining its characteristic opening system from the 1930s unchanged, the invention aimed to rationalize reinforced concrete construction sites and modifies the shape of the two coupler clamps to house the tube on one side, and to clamp metal formwork on the other. The 1945 patent was to be the last filed by Ferdinando in the building sector. In the heat of the reconstruction, Innocenti identified two new business directions: on one hand to convert the factories in Milan for the large-scale production of the popular two-wheeled vehicles (Lambret- ta), and on the other, to form a new company – Ponteggi Tubolari Dalmine-Innocenti S.p.A – to exploit their invention in the field of road infrastructure stemming from the motorway develop- ment plan. Therefore, while remaining at the helm of the new corporate setup to commercialize the “tube and coupler” system, Ferdinando left the technical scene and handed over his invention to the creativity of a team of structural engineers, to which he transferred all the patents filed un- der his name. Ponteggi’s Engineering Department, tasked with completing Innocenti’s invention to handle the loads required by the construction of new bridges, had 37 designers, and provided the support of expert engineering in the metal construction field. The young engineering squad, was put immediately to the test in the cambering of the viaducts on the Voltri to Albissola part of the Genoa-Savona motorway, the first post-war Italian motorway. So despite the standardised construction system, the framework punctuallly required ad hoc structural design to match the types of static viaducts and the local conditions. Designing the centerings for the 17 bridges of Voltri to Albissola section involved just as many structural layouts, each developed individually by Ponteggi’s engineers.

Autosole motorway

In May 1956, the first stone of the Autostrada del Sole motorway was laid, marking the be- ginning of Ponteggi’s involvement in the design of increasingly demanding temporary structures, especially for the construction of viaducts to cross the Apennines in the Bologna - Florence.

5th International Congress on Construction History I. Giannetti

Figure 4: Innocenti centering, Autostrada del Sole, Po viaduct (1958), Gambellato and Merizzano viaducts (1960) Before awarding the tender, Ponteggi’s engineers contacted the companies participating in the bid to design a new type of centering that could contribute to economically competitive of- fers. Given the leap in the scale of the viaducts, the company immediately started researching with the use of a larger tube – with a 60 mm diameter – to be used in conjunction with the classic 48 mm type. Meanwhile, the construction sites of the Milan-Bologna section had reached the banks of the river Po, and Ponteggi started installing a traditional tubular scaffold to cast the pre- stressed concrete girders designed by Silvano Zorzi: the impressive fan-shaped tubular lattice- work supported the platform for innovative on-site pre-stressed concrete construction, where workers took on the challenge of laying 35,000 cubic metres of concrete. Its success is undisputed, and not only among construction companies. The beautiful scaf- fold, as described by the mainstream reporters of the time, became an icon of the most significant structures of the Italian school of engineering during the years of the “Italian miracle”. The suc- cess of the Po construction further reinforced Ponteggi’s involvement in the construction sites of the Bologna-Florence section. With the game stake now raised, the company decided to bet a major slice of its resources on the ability of if its Engineering Department, with a view to reach the target of 5 billion in turnover by 1960. To assist the group of engineers of its Engineering Department, the company called upon Francesco Letterio Donato, scholar of Giuseppe Albenga, who was pursuing studies in the field of metal construction. The team, supported by Donato’s scientific contribution, examined the designs proposed for the viaducts by the contractors: the designs included two roads supported by two independent and parallel structures and, in most cases, the choice was to build reinforced concrete arches. The issue soon became clear: they had to work on the cambering of two twin reinforced concrete arches spaced approximately ten metres apart. Given the size of the arches, spanning more than 120 m and over 60 m high, making two centerings side by side was not via- ble, especially in economic terms. At the same time, preparing a centering to cast one of the arches, waiting for the concrete to mature, then disassembling and reassembling it for the other arch would take too long, causing substantial delays in the work plan with an adverse impact, once again, in economic terms. All that remained was only one way: to design a centering that, once assembled to cast the first arch, could be moved to the correct position to cast the second one. The most difficult issue to tackle was that considering the size of the frame – weighing at least 500 tonnes – how could it be moved within a construction site that had very little mechani- cal support?

5th International Congress on Construction History The Italian story of Ferdinando Innocenti’s tubolar scaffolding (1934-64)

Figure 5: Dalmine-Innocenti movable centering, Aglio viaduct, centering, lowering device, winches, 1958 The solution came as a quick wit, skilfully combining the traditional techniques of pre- industrial construction. Sand boxes and hand winches. The base of the centering would rest on a “lowering device”, a platform on vertical metal cyl- inders filled with sand, which could be gradually emptied. Once the lowering had taken place, the platform would reach a series of rollers on a guide, thereby allowing the centering to be moved using hand winches. In addition, the surface supporting the guide would be slightly slop- ing to compensate for the elevation of the centering lost during the lowering and to keep the cast- ing of the two arches aligned. The first movable centering was set up for the viaduct to cross the river Aglio. The viaduct has a total length of 440 m, of which 164 m are bridged by two side-by- side arches 64 m high. The gigantic archs required the creation of a much larger frame than those that had been tested until then, and its planned weight was over 700 tons. In May 1958, once the casting of the first arch had matured, the site prepared to shift the structure. Workers were divid- ed into teams coordinated by a “director” – the engineer L. Chinarelli – who would guide them through the operations using a sound system. The feat was to require two days of work. On the first day the centering was anchored to the ground and the winches and the guide planes were installed. On the morning of the following day, the workers took position to perform the shift: the sand cylinders placed under the base of the structure were slowly drained and the centering was gradually lowered, freeing the first arch from its framework. Even the slightest lowering of this huge “steel mountain” was a spectacular event. Completed within five hours, the centering base was lowered onto the rollers and was ready to be moved: the winch team began pulling, while the workers controlling the retaining cables kept the structure vertical. The operation re- quired four hours of demanding work, followed minute by minute by the cameras of RAI televi- sion, still the centering reached its position and height to cast the second arch, after shifting 13 meters balanced on an inclined plane. The colossal moveable centering was an international success, published in articles the lead- ing trade magazines, and was the subject of an industrial documentary chosen to represent Italy at the 1960 Locarno Film Festival.

Raise and fall

In less then one year, the operation was repeated in the nearby Sambro valley to cast an arch de- signed by Riccardo Morandi and for the construction of the arch centering over the river Gam- bellato, designed by Giulio Krall.

5th International Congress on Construction History I. Giannetti

Figure 6: Innocenti centerings, Nervi’s Palasport, Rome (1957), Pirelli skyscraper, Milan, 1958; Lora viaduct (1959) The extraordinary achievement of the centerings of the Apennines was echoed by Ponteggi’s op- erations in the construction for the Olympic Games in Rome. During those same months, in fact, Pier Luigi Nervi used the “tube and coupler” method to support the thousands of prefabricated elements that were used to make the domes of his Palasports. The joint use of the two systems is iconic of the “craftsmanship” of the ingenious challenge taken up by the Italian engineers, in a low-mechanisation construction site, that characterised the Italian engineering masterpieces of those years (Iori, Poretti 2013). In those months, the system was, indeed, employed for the design of high-rise scaffolding, such as the one used by Nervi and Arturo Danusso to build the Pirelli skyscraper in Milan. The structure presented critical areas where “instability” could occur “unexpectedly”. Analogous phenomenon could have happened in tube towers, which were increasingly popular for casting the pre-stressed beams of the girder viaducts. Most effective scientific studies were needed. Thus, on 2 February 1959, the University of Pisa opened the Centre for Studies on Metal Con- structions, funded by Dalmine and directed by Donato. The researchers of the Centre, however, had not yet published the outcome of their efforts when, on 24 October 1959 “at 8:30 am, a sinis- ter thunder suddenly broke the silence of the Tuscan countryside”, around 200 tons of concrete, iron and wood plunged into the river Lora, after a fall of over 50 meters, tragically sweeping away four workers. The collapse was of one of the high tube towers that had been installed by Ponteggi to cast the pre-stressed girders of the viaduct on the Lora, suddenly overshadowing, just a few kilometres away from the Aglio valley, the success and popularity of the steel giants: “in a matter of seconds, the superb frame of iron tubes bent, split apart and collapsed like a house of cards”.That same construction site where, a year earlier, the technique had reached a remarkable milestone, had now became a dangerous place where people had lost their lives due to the inter- ests of constructors and the negligence of their engineers; legal and media investigations imme- diately followed. Ponteggi commissioned the Experimental Institute for Models and Structures (ISMES) of Bergamo to carry out a series of tests on models designed to simulate the conditions of the collapse and to analyse the frame under different load conditions. Pillars 4 and 5 of the Lora frame were re-built in a laboratory. With 18 mm and 14 mm tubes, specially produced to- gether with miniature couplers, the ISMES engineers built two models: the first reproducing the whole assembly of the two pillars, and the second the large central pillar. Despite the “bit of welding” added to more closely match the original couplers, the test re- sults confirmed the assumption that a pillar gave way under a concentrated load of concrete, rul- ing out the possibility of undermining.

5th International Congress on Construction History The Italian story of Ferdinando Innocenti’s tubolar scaffolding (1934-64)

Figure 7: Ismes laboratory, structural model of the centering (1959); Innocenti centering, Breguenzer viaduct (1965) Following the accident, in 1960 Ponteggi’s business in the centering sector dropped by 60% and, for the first time, the “centering insurance provision” appeared in its financial statements budget, set up as a result of the decision to insure itself against liability risks. So, when, in 1961, a 235 m arch designed by Riccardo Morandi and built by Sogene was cast over the Fiumarella valley in Catanzaro it passed almost unnoticed. The cambering of the arch, however spectacular (being the largest ever made by the company), met new security standards: based on three fans and resting on three reinforced concrete uprights designed by Ponteggi to replace the tubular towers. Only at the end of 1962, did Ponteggi’s balance sheet surprisingly show a remarkable upturn in sales of couplers in the centering sector. Indeed, the Autostrada del Sole motorway was setting up construction sites for the Florence-Rome section with large arches to cross the Arno river and valleys along the Tiber river. Despite recent uncertainties and the initial widespread use of a sliding formwork for the construction of girder viaducts, the Dalmine-Innocenti tubular cen- tering was still the fastest and cheapest way to cast reinforced concrete arches. With the closure of the construction sites of the Autostrada del Sole in 1964, Ponteggi experienced a further de- crease in the centering sector, while on the Breguenzer river in Austria, a last spectacular feat was being set in motion: the construction of a giant tubular centering to cast a thin stiffening vaulted arch spanning 275 metres. It was Ponteggi’s last daring work in Europe. That anticipat- ed the end of the cast in place, reinforced concrete arch era and the dissolution of the distinguish- ing features of Italian construction site that had been represented Innocenti’s little coupler.

REFERENCES The historical reconstruction is mainly based on archival sources (Fondazione Dalmine Historical Archive, Dalmine; Patent and Trademark Italian Office Historical Archive, Rome; IRI Historical Archive, Rome; ISMES His- torical Archive, Bergamo; Central Archive of the State, Rome). The references are used to frame the story in the broader context of the history of Italian structural engineering.

Iori, Tullia, Poretti, Sergio, 2014. “En Exiting investigation”, T. Iori, S. Poretti eds., SIXXI 1, Rome: Gangemi Editore (7-10). Iori, Tullia, Poretti, Sergio, 2013. “La scuola italiana di Ingegneria”, V.Marchis, F.Profumo eds. “Enciclopedia Italiana di scienze lettere ed arti, Ottava Appanedice. Il contributo ital- iano alla storia del pensiero. Tecnica”, Istituto della Enciclopedia Italiana fondata da Gio- vanni Treccani (521-28).

5th International Congress on Construction History