Japon | EPFL Graph Search

Le Japon (en japonais : 日本, Nihon, ou Nippon, ) est un pays insulaire de l'Asie de l'Est, situé entre l'océan Pacifique et la mer du Japon, à l'est de la Chine, de la Corée du Sud, de la Corée du Nord et de la Russie, et au nord de Taïwan. Étymologiquement, les kanjis (caractères chinois) qui composent le nom du Japon signifient « pays (国, kuni) d'origine (本, hon) du Soleil (日, ni) » ; c'est ainsi que le Japon est désigné comme le « pays du soleil levant ». Le Japon forme, depuis 1945, un archipel dont le nombre d'îles varie, suivant les estimations, de (de plus de ), dont les quatre plus grandes sont Hokkaidō, Honshū, Shikoku et Kyūshū, représentant à elles seules 95 % de la superficie terrestre du pays. L'archipel s'étend sur plus de trois mille kilomètres. La plupart des îles sont montagneuses, parfois volcaniques. Ainsi, le plus haut sommet du Japon, le mont Fuji (), est un volcan dont la dernière éruption a eu lieu en 1707. Le Japon est le onzième pays le plus peuplé du m

La création d'une japonité moderne (1870-1940), ou Le regard des architectes européens sur le Japon

Irène Elizabeth Vogel Chevroulet

This thesis questions the fundamentals and modes characterising the European architects' way of looking at Japanese architecture and garden art between 1870 and 1940. It establishes the corpus of the major writings and of other texts published by their Occidental and Japanese contemporaries in English, French and German. We analyse the writings' major issues, outstanding specifics and realisations. We detect and describe the creation of a modern Japan-ness through the writings of four major protagonists. Firstly, Josiah Conder was professor of Architectural History and Theory at Tokyo Imperial College and later considered as the "father of modern architecture" in Japan. We discuss his articles and books, published between 1877 and 1893, as being inaugural as well as forerunners of Japan-ness. Between 1903 and 1910, the architect Chûta Itô and the art historian Kakuzô Okakura gave its premises in their publications. The engineer Franz Baltzer as well as the architects Ralph A. Cram and Frank Lloyd Wright confirmed some of these ideas in their books published between 1903 and 1912. Secondly, we study writings from an architect who never traveled to Japan : Robert Mallet-Stevens. His articles, written in France from 1911 et 1913, were an indirect reference to Conder's articles. Thirdly, we analyse the theoretical and innovative works published by Bruno Taut between 1924 and 1937. We look at the way in which he valued and consolidated an intercultural Japan-ness. We question the existence of a Japan-ness in garden arts' writings. We establish how his contemporaries spread Japan-ness specificities : the architects Wajiro Kon, Kôji Fujii, Tetsuro Yoshida, Sutemi Horiguchi, Wells Coates, Richard Neutra and Antonin Raymond, the art historian Jirô Harada, the landscape designers – Tsuyoshi Tamura, Percy. S. Cane et Christopher Tunnard –, and the writer Jun'ichiro Tanizaki. We identify which specificities had already been defined by Itô, Kon and Horiguchi before Taut validation. Fourthly, Charlotte Perriand confirmed this established modern Japan-ness as a source of inspiration with her notes taken during her stay in Japan between 1940 and 1941. The thesis chronicles the impact of her notes onto some of her realisations in Japan and later in France. Thanks to this comparative analysis of texts, the thesis argues that the European gaze towards Japan is reflecting its preoccupations towards justifications for its own architectural development. This gaze is also orientated by the interests of the Japanese themselves. These are looking for an international recognition of their traditional architecture. We describe then how Japan-ness is created through writings and how it works as an appropriation of modernity enabling Japanese architecture to step in an avant-garde role. This creation follows two stages. The first one is a process of distinction from Asian architecture by identification and reinforcement of Japanese specifics. At its core lies the discourse upon the differences of the Japanese shintoist and zen soul. The second one is a process of sorting out common specificities with Western avant-garde ones. This time, the discourse concerns abstract similarities. The whole set of Japan-ness specificities defines an intercultural architecture which distinguishes itself both from Japonisme and from Occidentalisme. Lastly, the results show the profits gained by this European gaze and taken into account in their own architecture.

EPFL2009

Welded moment connections with highly dissipative panel zones for enhanced seismic performance of steel moment frames

Andronikos Skiadopoulos

Research conducted after the 1994 Northridge earthquake in the U.S. and the 1995 Kobe earthquake in Japan led to the development of today's pre-qualified beam-to-column connections for capacity-designed steel moment resisting frames (MRFs). Welded moment connections feature weld backing bars that should be removed after the execution of complete joint penetration groove welds at the bottom beam flange-to-column flange joint. On the other hand, advancements in steel and weld materials, as well as fabrication techniques, allow for the exploitation of simplified weld details at this location. In welded moment connections for seismic applications, the participation of the beam-to-column web panel zones in the energy dissipation is generally limited during an earthquake event. In such a design context, beam local buckling is likely even at modest lateral drift demands, thereby engendering structural repair costs in the aftermath of earthquakes. The primary reasons for such a seismic design practice are twofold. The first one relates to known limitations of panel zone design models that compromise our ability to effectively balance the seismic design of fully restrained beam-to-column connections. The second one relates to the panel zone kinking that could increase the fracture potential of beam-to-column connections. However, recent experiments in the literature provide controversial results regarding the same matter.This doctoral thesis aims at advancing the state-of-knowledge regarding the seismic design and behavior of steel MRFs with highly dissipative panel zones. A new panel zone design model was first developed. This model addresses the limitations of all available panel zone models in the literature. The model was validated thoroughly with about 100 available experiments that encompass a broad range of geometric parameters. The panel zone model can effectively enable a balanced seismic design of welded moment connections with inelastic panel zones. One step further, this thesis revisited the current detailing of welded connections. Simplifications in their fabrication process were proposed by intentionally keeping a customized beveled backing bar in place, without impairing the connection's ductility under cyclic loading. The proposed connection weld detail is substantiated by continuum finite element analyses and full-scale experiments on welded moment connections with highly dissipative panel zones. It is demonstrated that, contrary to the current design paradigm, a stable hysteretic response is achieved up until lateral drift demands of at least 7% rad, thereby diminishing the cyclic deterioration in story shear resistance. As such, the seismic stability of steel MRFs is only governed by global P-Delta effects. Quantitative seismic response characteristics of steel MRFs with highly dissipative panel zones through large-scale systel-level parametric studies were also provided. It is shown that steel MRFs with highly inelastic panel zones, have up to two times lower mean annual frequency of collapse than corresponding results with steel MRFs designed with the current status quo. It is also demonstrated that steel MRFs with inelastic panel zones, enjoy up to 50% reduction in residual story drift ratios at a design-basis earthquake; their beam-to-column connections do not experience fractures due to panel zone kinking; and local buckling in steel beams is very limited even at low probability of occurrence seismic events.

EPFL2022

La création d'une japonité moderne (1870-1940), ou Le regard des architectes européens sur le Japon

Irène Elizabeth Vogel Chevroulet

EPFL2009

Welded moment connections with highly dissipative panel zones for enhanced seismic performance of steel moment frames

Andronikos Skiadopoulos

EPFL2022