Seismic vulnerability of Modern Architecture building's: Le Corbusier style: a case study

Abstract

In Portugal, at the end of the World War II, a new generation of architects emerged, influenced by the Modern Movement Architecture, born in Central-Europe in the early twenties but now influenced also by the Modern Brazilian Architecture. They worked with new typologies, such as multifamily high-rise buildings, and built them in the most important cities of the country, during the fifties, reflecting the principles of the Modernity and with a strong formal conception inspired in the International Style’s codes. Concrete, as material and technology, allowed that those “Unity Centre” buildings become modern objects, expressing the five-point formula that Le Corbusier enounced in 1927 and draw at the “Unité d’Habitation de Marseille”, namely: the building lifted in pilotis, the free design of the plan, the free design of the façade, the unbroken horizontal window and the roof terrace. In Lisbon, late forties urban plans transformed and expanded the city, creating modulated buildings repeated in great extensions – that was a progressist idea of standardization. The Infante Santo complex is a successful adaptation to the Lisbon reality of the Modern Urbanism and Architecture. In the fifties, it was built a large number of Modern housing buildings in Lisbon, with structural characteristics that, in certain conditions, can induce weaknesses in structural behaviour, especially under earthquake loading. For example, the concept of buildings lifted in pilotis can strongly facilitate the occurrence of soft-storey mechanisms, which turns these structures very vulnerable to earthquake actions. The development and calibration of refined numerical tools, as well as, assessment and design codes makes feasible the structural safety assessment of existing buildings. To investigate the vulnerability of this type of construction, one building representative of the Modern Architecture, at the Infante Santo Avenue, was studied. This building was studied with the non-linear dynamic analysis program PORANL, which allows the safety evaluation according to the recently proposed standards.