Crossed-arch vaults in late-gothic and early Renaissance vaulting: a problem in building technology transfer

Crossed-arch vaults are a particular type of ribbed vaults. Their main feature is that the ribs that form the vault are intertwined, forming polygons or stars and leaving an empty space in the middle. The firsts appear in Córdoba in the second half of the 10th Century. Afterwards, the type diffused through Spain and North Africa, 11th_13th Centuries. These vaults reappear in Armenia in the 13th Century. In the 14th and 15th Century a few examples are found both in England (Durham, Raby) and Central Europe (Prague, Landshut, Vienna). At about the same time, Leonardo da Vinci produced designs for the Tiburio (Ciborium) of Milan cathedral with a cross-arched structure and proposed tests to assess the strength; he also, made use of the same pattern of vault for Renaissance centralized churches. Eventually, the type can be tracked through the 17th (Guarini) and 18th (Vittone) Centuries, until Spanish post war architecture in the 1940-60s (Moya). Some questions arose, which so far, have not been answered. How was it possible that a particular type of vault had such enormous geographical spread? How was it transmitted from Córdoba to the Caucasus? The matter is one of transfer of knowledge, ideas, and technology; it relates both aesthetics and construction.

El lenguaje de la estructura: Mies van der Rohe y la construcción con acero y hormigón

John Summerson, en El Lenguaje Clásico de la Arquitectura, defiende que los órdenes clásicos que empleaban los arquitectos romanos para decorar sus edificios, no tienen una función estructural pero hacen expresivos a los edificios. Les hacen hablar. Arthur Schopenhauer afirma que “el destino de la Bella Arquitectura es poner de manifiesto la lucha entre el peso y la rigidez de los elementos estructurales”. Y Auguste Perret define la Arquitectura como “el arte de hacer cantar al punto de apoyo”. El objetivo de esta Tesis Doctoral es profundizar en la capacidad de expresión de la estructura. A través del estudio de las estructuras históricas, que se realiza en la primera parte de la Tesis, podemos concluir que existen tres categorías, tres maneras de expresión de la Estructura. Estructuras Vistas, que hablan, Estructuras Ocultas, que se esconden y Estructuras Ilusorias, que fingen. El Partenón y la Sainte Chapelle de París se estudian en el apartado de Estructuras Vistas. El Panteón, el Palacio de Carlos V, la Catedral de San Pablo en Londres, y otras arquitecturas renacentistas y romanas, en el apartado de Estructuras Ocultas. Y como Estructuras Ilusorias, la Alhambra (Dos Hermanas, Comares, el Patio de los Leones), Santa Sofía, y otras arquitecturas del barroco italiano. En la segunda parte de la Tesis se analiza la obra completa de Mies van der Rohe desde el punto de vista de esas tres categorías. Lo visto, lo oculto y lo ilusorio en las estructuras de Mies. Se estudia la evolución en la estructura de la casa, desde las primeras casas con Estructura Oculta de muro de ladrillo, hasta las últimas casas con Estructura Vista y columnas adelantadas, pasando por una etapa intermedia de casas con estructura mixta de muro de ladrillo en la que el acero comienza a hacer su aparición. Se analizan también seis soluciones estructurales en los Bloques y en las Torres: Estructura Vista reverberante, expresiva o inexpresiva vs Estructura Oculta con vestido horizontal, vestido reticular o vestido vertical. Y por último, se estudian las tres soluciones de Estructura Ilusoria que emplea Mies en sus Pabellones. La metodología de trabajo que se ha empleado se divide en cuatro apartados: El análisis bibliográfico; el análisis in situ de los edificios, que nos permite comprobar, por ejemplo, los efectos lumínicos de la columna acanalada del Partenón, o el efecto reverberante de las columnas de la Weissenhofsiedlung; el análisis crítico de planos y detalles constructivos, que nos lleva a concluir que la disposición de pantallas del Pabellón de Barcelona anula la lectura de la crujía estructural, y que la columna del restaurante Cantor se dispone con su alma perpendicular a la cercha, y no paralela, como cabría suponer si se quisiera aprovechar toda la capacidad portante del perfil en H; y por último, el análisis numérico y estructural, que nos lleva a confirmar el sobredimensionado de la Estructura del Patio de los Leones de la Alhambra o el sobredimensionado de la Estructura de la Casa Farnsworth. Lo que se confirma con esta Tesis Doctoral es que la Estructura es algo más, mucho más, que sólo transmisión de las cargas. ABSTRACT John Summerson, in The Classic Language of Architecture, argues that the classic orders used by Roman architects in the decoration of their buildings did not have a structural function, but made buildings expressive. They make them speak. Arthur Schopenhauer affirms that “the goal of Great Architecture is to highlight the struggle between the gravity and rigidity of structural elements”. And Auguste Perret defines Architecture as “the art of making the points of support sing”. The objective of this Doctoral Thesis is to examine the expressive capacity of structure. Following a study of historic structures in the first part of the thesis, we conclude that three categories exist, three ways of expressing Structure. Visible Structures that speak, Concealed Structures that are hidden and Illusory Structures that pretend. The Parthenon and the Sainte Chapelle in Paris are studied in the section on Visible Structures. The Pantheon, the Palace of Charles V, Saint Paul’s Cathedral in London, and other Renaissance and Roman architectures are dealt with in the Concealed Structures section. And, as examples of Illusory Structures, we focus on the Alhambra (The Hall of the Two Sisters, the Comares and the Court of the Lions), Saint Sophia, and other Italian Baroque architectures. In the second part of the Thesis the complete work of Mies van der Rohe is analysed from the perspective of these three categories. The visible, the concealed and the illusory, in the structures of Mies. We study how the structure of the house evolves, from the first houses with the Hidden Structure of the brick wall, to the later houses with Visible Structures and columns, via an intermediate phase of mixed-structure houses with brick walls, where steel first began to make its appearance. We also analyse six structural solutions in the Blocks and Towers: reverberant, expressive or inexpressive Visible Structure vs Concealed Structure with horizontal cladding, reticular cladding or vertical cladding. And finally, we look at the three Illusory Structure solutions that Mies employs in his Pavilions. The methodology employed is divided into four sections: a bibliographic analysis; an analysis in situ of the buildings, which allows us to test, for example, the lighting effects of the fluted column in the Parthenon, or the reverberant effect of the Weissenhofsiedlung columns; a critical analysis of plans and constructive details, which leads us to conclude that the arrangement of panels in the Barcelona Pavilion cancels out the structural centreline, and that the column in the Cantor restaurant is placed with its web perpendicular to the truss, and not parallel to it, as one might expect if one wanted to avail of all the load-bearing capacity of the H beam; and lastly, a numeric and structural analysis, which confirms the oversizing of the Court of the Lions structure in the Alhambra or the oversized structure of Farnsworth House. All of which confirms in this Doctoral Thesis that structure is something more, much more, than a mere conveyor of loads.

The African-American Islamic Renaissance and the Rise of the Nation of Islam

This dissertation examines African-American Islamic culture from 1920 through 1959, a period I label the "African-American Islamic Renaissance" (AAIR). The AAIR is characterized by a significant increase in interest in Islam, extreme diversity in views about Islam, and the absence of a single organization dominating African-American Islamic culture for a significant amount of time. Previous works dealing with African-American Islam in this period have failed to fully recognize these features, particularly the last of these. As a result, explanations for the rise of the Nation of Islam (NOI) have not satisfactorily explained why it was only the NOI--and not other Islamic groups that were more popular than the NOI up until the mid-1950s--that became a "mass movement," gaining the allegiance of tens of thousands of African Americans. There has been some tendency, for instance, to assume that the NOI was the most popular African-American Islamic group by the early 1950s, a notion that is probably an inference drawn from two other popular but inaccurate assumptions: that the NOI's rise was due primarily to its radical racialized doctrines and its charismatic leaders, particularly Malcolm X, who became a popular minister for the group in the early 1950s. I argue, however, that the NOI was in fact not the most popular African-American Islamic group until at least 1955, and even as late as 1959 its official membership numbers were not particularly large by AAIR standards. Also, its doctrines were not especially unique in the AAIR, nor was its having extremely charismatic leaders. I contend that the success of the NOI in the mid-to-late 1950s was the result of three levels of changes at the time: internal, external in the AAIR community, and external in the broader U.S, culture.

Modern Classics : Andy Warhol and the Renaissance Masters

"This paper explores Warhol’s final and largest series entitled the Last Supper series in which the artist appropriated the work of Leonardo da Vinci’s original fifteenth century painting, replicating the image through repetition, radical cropping, and washes of neon color. While many scholars conclude this group of works is inspired by Warhol’s religious beliefs, others interpret these paintings as typical Warhol appropriation without religious association, but consistent with the artist’s interest in the cultural commodity of famous images"

Cabecera cuadrada renacentista con bóveda pseudo-esférica cruzada en la iglesia Santiago de Orihuela (Alicante)

Jerónimo Quijano fue uno de los ilustres arquitectos destacados del Renacimiento pleno en España. Su obra, la iglesia de Santiago en Orihuela -Alicante- posee una Capilla Mayor renacentista, de carácter funerario, de planta central y adosada a una nave gótica. Destaca su bóveda superior de 4 pares de arcos entrecruzados y revirados. Al ser dobles se reduce la superficie central de plementería y se gana en resistencia. Es de complicada geometría esférica y cuadrada a la vez: bóveda pseudo-vaída (esférica solo hasta los arcos exteriores) y plementería lateral adaptándose a la planta cuadrada. Supone la fusión de la antigüedad clásica con la tradición hispanomusulmana. Como referencia, se estudia sucintamente la Capilla Benavides en Baeza - Jaén-, obra de Andrés de Vandelvira e incluida en el tratado de arquitectura de su hijo Alonso, la cual plantea un gran espacio cuadrado cubierto por una bóveda vaída y reforzada por 4 arcos entrecruzados.

Are drawings dead? …and performance over aesthetics?

When the act of 'drawing' became what can only be called formalised, (whose growth can be said to have blossomed during the Renaissance), there developed a separation between the drawing and its procurement. Recently, David Ross Scheer, in his book ‘The Death of Drawing, Architecture in the Age of Simulation’ wrote: ‘…whereas architectural drawings exist to represent construction, architectural simulations exist to anticipate building performance.’ Meanwhile, Paolo Belardi, in his work ‘Why Architects Still Draw’ likens a drawing to an acorn, where he says: ‘It is the paradox of the acorn: a project emerges from a drawing – even from a sketch, rough and inchoate - just as an oak tree emerges from an acorn.’ He tells us that Giorgio Vasari would work late at night ‘seeking to solve the problems of perspective’ and he makes a passionate plea that this reflective process allows the concept to evolve, grow and/or develop. However, without belittling Belardi, the virtual model now needs this self-same treatment where it is nurtured, coaxed and encouraged to be the inchoate blueprint of the resultant oak tree. The model now too can embrace the creative process going through the first phase of preparation, where it focuses on the problem. The manipulation of the available material can then be incubated so that it is reasoned and generates feedback. This paper serves to align this shift in perception, methodologies and assess whether the 2D paper abstraction still has a purpose and role in today’s digital world!

The role of EU Special Representatives in the post-Lisbon foreign policy system: A renaissance? IES Policy Brief Issue 2012/02/June 2012

Summary. EU Special Representatives have been deployed since 1996 in order to contribute to the EU’s crisis management efforts in various crisis regions. As they are not part of the formal hierarchy of the European External Action Service and thus a rather flexible foreign policy instrument at the disposal of the Member States, new special representatives have been appointed in 2011 and 2012. This Policy Brief argues that the representatives’ autonomy must not necessarily lead to ‘clashes of competence’ with the EU’s diplomatic service.

Performance of historic stone building materials and systems : observations by architects, engineers and building conservators : excerpts from workshop discussions held on August 10, 1987, funded by the U.S. Environmental Protection Agency and the U.S. Department of the Interior, National Park Service, Cultural Resources Acid Rain Research Program.

"June 1988."