Learning from Slussen: place, idea and process in the transformation of central urban interstices

Over the last two decades the Slussen in Stockholm designed by Tage William-Olsson in 1935 has been the subject of an intense debate about how to update it to the contemporary needs. Tabula rasa reconstruction or renovation? This lively discussion, however, has resulted in a nal proposal granted by the expertise of an international rm but controversial for its political management, opposed to several social groups and, above all, highly problematic in terms of urban form and sustainability. The strategic location of this place, the indelible presence of its modern shape in the collective imaginary or the overwhelming force of the new paradigms of public space, have ended up provoking a range of more than twenty- ve proposals in a short period of time. But while today this process seems to be settled and the demolition works of the original structure has already started, it would be still useful to draw some conclusions relevant to other similar interstitial sites in European compact cities where architecture, infrastructure, public space and landscape meet in such an intense way. Thus, this paper summarizes some of the last arguments of the on-going doctoral thesis about the recent evolution of Slussen according to four di erent outstanding topics: the form of place and history as an undeniable premise; the strength of tactics versus the power of the image in the process; the importance of time in the sequence of urban decision-making and, nally, the weight of urban culture as a key argument in contemporary urban transformation processes.Peer ReviewedPostprint (published version

Natural urbanity on the urban edge : design considerations for Torre-Negra, Collserola

Pòster (subtítol): Notes on the Final Degree Project, developed by Alvaro Clua at the Barcelona School of Architecture (UPC-2012), under the supervision of prf. A. LinaresIn the shade of the Collserola range, near the old road that links the Roman Barcino with the hinterland of the Valle`s, the natural environment of Torre Negra has for almost thirty years now been one of the most endangered and fragile spaces. Here we can see the con uence of ravines and the Sant Crist and Riera de Sant Medir rivers, one of the last areas of farmland near Collserola Park, the historical, symbolic presence of the Torre Negra old country house (which originally served as a watchtower of the Monastery of Sant Cugat del Valle's), the ruins of a ceramic brickyard, modern-day equestrian centres, international schools and tennis clubs. All this under the shadow of the Pi d’en Xandri, a much-loved pine tree measuring some 23 metres tall. This unique local icon, increasingly present in the collective imagination, clearly re ects the contradiction between human pressure for property and the widely shared desire to promote ecological preservation. But while on the one hand the 1987 PEPco (Special Ordinance and Protection Plan for Collserola) de ned the area as “agricultural area with landscape value”, the last sentence by the Spanish Supreme Court in 2016 and the Catalan Supreme Court determined that it “does not meet” the conditions laid out in the Law on Natural Heritage and Biodiversity of Natural Spaces, and therefore the area remains subject to property speculation. In reality, though, this burning controversy has served only to leave the superb Collserola area on standby, while positions on either side harden. This article aims to shed some light onto this di icult issue through an exploratory project carried out by the author of this article with the aim of answering the following questions: What design criteria should be taken into account to solidify an area as uncertain as Torre Negra, where there is insu icient strength in terms of ecological or heritage value, but where there is an underlying interest? What design programmes, guidelines and arguments can be used to reactivate the peri-urban city edges? How can we integrate urban and natural spaces?Peer ReviewedPostprint (published version

Slussen 1935-2015: diagnóstico de una ruina moderna

El proyecto del Slussen en Estocolmo es hoy una ruina del movimiento moderno. Aquella visión optimista y eterna de la arquitectura funcionalista se presenta incierta y desproporcionada tras menos de un siglo de pervivencia. Paredes desconchadas, metales oxidados por el salitre, azulejos rotos, tiendas en decadencia y paseantes en sombra muestran un espacio hoy muy distinto de aquella “elegancia” que pregonara en 1935 el periódico Svenska Dagbladet ante el proyecto de Tage William-Olsson. ¿Cuáles son las causas de la decadencia de ese intersticio urbano? ¿Es en origen un proyecto erróneo, una historia malograda? Las respuestas se argumentan desde un recorrido intencionado por algunos momentos clave de su transformación: en el rastro de esbozos nunca realizados, en las vacilaciones del proyecto original, en las instantáneas de su inauguración, en sus detalles de acabados y comercio o finalmente en las imágenes presentadas al concurso internacional de 2008. Quizás puedan argumentarse ahí las futuras intervenciones que se ciernen sobre el Slussen moribundo: ¿mirada nostálgica, oportunismo, tabula rasa?The Slussen project in Stockholm is today a ruin of the modern movement. After less than a century of life, the place appears in an uncertain and disproportionate way, far from the optimistic and eternal vision of functionalist architecture. Flaking walls, oxidized metals, broken tiles, decadent shops and pedestrians lost in the shadow of the infrastructure show a very different space of that "elegant" prototype declared by the Svenska Dagbladet in 1935 on the built project of Tage William-Olsson. Which are the reasons for the decadence of this urban interstice? Is the original Slussen designed by Tage William-Olsson a wrong project, a failed story? In this article, answers are argued following an intentional trip through some key episodes of its existence: through the traces of sketches ever executed and the variations of the original project, through some images of its inauguration and the subtle details in the bright shopping stores and, finally, through the reading of the proposals presented to the recent international competition in 2008. Perhaps the future transformation of the dying Slussen could learn some arguments from the experience of its own past. ¿Nostalgic view, opportunism, tabula rasa

Lanzarote Dynamic Square

MencióPostprint (published version

A city made of rooms. Revisiting the interactions between urban planning and building typology in Mario Ridolfi’s projects for Terni

This is an Accepted Manuscript of an article published by Taylor & Francis in Planning Perspectives on 24/04/2019, available online: http://www.tandfonline.com/10.1080/02665433.2019.1607538Mario Ridolfi’s lifelong work in the area around the Corso del Popolo in the city of Terni has merited special attention among researchers because of its sensitiveness towards the historical surroundings, its ability to integrate town-planning and architecture and its capacity to transform the city’s skin and structure. The aim of the paper is to shed light on the origins, design strategies and translation into architecture that informed the approval of the Variante al Piano di Ricostruzione Corso del Popolo, piazza del Popolo e zone adiacenti in 1959. A comparative analysis of mainly unpublished, original sketches dating back to 1932 helps to understand the planning precedents that ultimately led to the decision to open the Corso del Popolo (1984–1932), the variations of the specific layout of this urban project from 1932 to its approval in 1959 and the unique application of planning strategies into Ridolfi’s buildings for central Terni. The study reveals the persistence of previous planning ideas that were not proposed but accepted by Ridolfi, the depiction of the ‘squared street’ as a new paradigm of open space, and the intrinsic paradoxes that informed the difficult embedding of the palazzina typology into the fragile urban fabric of the old city centre.Peer ReviewedPostprint (author's final draft

Modeling Barcelona sidewalks: a high resolution urban scale assessment of the geometric attributes of the walkable network

Within the framework of urban pedestrian networks, this paper presents a method of modeling the street network from the perspective of foot traffic, beyond the vehicle-focused street centerline representation approach in transportation research. A scalable method to extract the centerlines of the complete walkable urban area from its polygon representation at a one-meter resolution is discussed, using open-source tools. To evaluate the betweenness centrality in a spatially directed graph, the process is applied to the study of the ‘walkable Barcelona’, focusing on three key parameters: 1) the street width, 2) the longitudinal slope, and 3) the crosswalks connecting the sidewalk platforms. The results identify the uneven distribution of these parameters within a complex urban fabric, and the high-resolution cartography allows the identification of critical areas within the network, introducing future lines of research and applications of the workflow. This is especially relevant considering the increasing awareness of citizens and the urban agendas worldwide, aimed at improving and widening the sidewalk infrastructure that supports local activity in cities.Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i InfraestructuraObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles::11.2 - Per a 2030, proporcionar accés a sistemes de transport segurs, assequibles, accessi­bles i sostenibles per a totes les persones, i millorar la seguretat viària, en particular mitjan­çant l’ampliació del transport públic, amb especial atenció a les necessitats de les persones en situació vulnerable, dones, nenes, nens, persones amb discapacitat i persones gransObjectius de Desenvolupament Sostenible::9 - Indústria, Innovació i Infraestructura::9.1 - Desenvolupar infraestructures fiables, sostenibles, resilients i de qualitat, incloent infraestructures regionals i transfrontereres, per tal de donar suport al desenvolupament econòmic i al benestar humà, amb especial atenció a l’accés assequible i equitatiu per a totes les personesPostprint (published version

Urban opportunities and conflicts around street musicians: the relationship between the configuration of public space and outdoor acoustics in Ciutat Vella, Barcelona

The practice of busking and street music performance is becoming key to the identity of cities. However, although the spatial configuration and acoustics of historic city centres are interrelated, few rigorous studies have been undertaken on this area. The paper presents the results of a quantitative and comparative analysis of the space syntax configuration and on-site sound recordings in four main open environments within the inner core of Barcelona. The aim of this work is to highlight the conflict points between outdoor acoustics and movement flows in order to inform future designs and management of those public spaces.Postprint (published version

An approach to visual interaction analysis of urban spaces: Central Barcelona as a case study

This is an Accepted Manuscript of an article published by Taylor & Francis in Journal of Urbanism on 28/03/2021, available online: http://www.tandfonline.com/10.1080/17549175.2021.1886972Beyond the binary, traditional, figure-ground reading of urban patterns, this research presents a graduated expression of the geometry of urban spaces from a perceptive point of view. This highlights the spatial relationships and introduces a new set of criteria to evaluate contemporary open spaces according to visual experience. The study produces an innovative reading of central Barcelona by mapping of Visual Clustering Coefficient, one of the parameters derived from the Visual Graph Analysis of isovists.Peer ReviewedObjectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats SosteniblesPostprint (author's final draft

ITINERA

Amb la col·laboració de Josep Llorca BofíFinalistaPostprint (published version

Outdoor terraces in Barcelona and Milan: configuration of new spaces for social interaction

This work approaches the phenomenon of the outdoor terraces of bars and restaurants, analysing the role of these privately owned collective elements whose layout has shaped the urban landscape at the pavement level for more than a century, and whose presence has become essential in the streets of many cities after a pandemic. The research highlights the interest of terraces as dynamic elements of urbanity: private domains in the public space where people eat collectively; they are apparently simple units that synthesise complex conflicts between individual behaviours and property boundary conditions. The investigation shows the increasing expansion that outdoor terraces have experienced since 2020, using the cities of Barcelona and Milan as case studies. A series of GIS maps show the image of both cities before and after the pandemic, allowing us to evaluate the amount of public space allocated to terraces, measure their increase in number and surface, establish the proportions of occupation of the street and find the patterns of concentration in the public space. Finally, the article offers some policy and planning recommendations based on the research findings.Peer ReviewedPostprint (published version