Upside-down ship’s kel-shaped vaults as a contemporary design criteria. The case of the Palace of the Dukes of Braganza in Guimarães (Portugal)

Abstract

A contemporary worldwide trend is exposing the structural elements of a building to create an articulate and complex architecture whose lines of force give robustness, stability and, at the same time, a sort of lightness and frivolity to the entire construction. However, the combination between the visual conception of architecture and the principles of statics is not new to the world of construction. Exposed structure as a design approach may be observed in many historical buildings, either public, religious or private, and in several cultural and geographical areas where exposed structures communicate power, solidity, and rigour along with an instance of economy and lightness. In this work, we will focus on the wooden upside-down ship’s keel -shaped vaults with particular reference to the European area. Such a structure may be considered real constructive typology. Generally speaking, keel-shaped roofs, union of structural paradigms and architectural instances, spread during the Middle Age and combined deep structural studies with formal architectural valences to create shocking inner spaces where architectural partitions and the entire building empirical static are called into question. Many churches or civic palaces show such a wooden vaults that, combined with other structural elements, in sight or hidden, generate a high and articulate roof that, despite its huge dimensions, looks lighter and entangling in its ascent upwards. We hardly believe that such a structure, even in a simplified form, may be used nowadays to solve in a brilliant and unusual way the structural supports of articulate roofs of large buildings of monumental valence, as churches or representative halls. In such a vision, we will analyse the Palace of the Dukes of Braganza in Guimarães which is a Portuguese National Palace completely restored, and partially rebuilt, between 1937-1959. In such a reconstruction, large wooden ship’s keel -shaped vaults were built to support the roofs of the banqueting hall, honour hall and chapel. Those structures will be contextualized into the main typology and we will try to explain, and demonstrate, why about 60 years ago a contemporary architect designed a so complex construction which is a reminiscence of the old times. Furthermore, by means of some structural modelling, we will illustrate a real possible use of such a structure using various modern materials and in respect of current standards and regulations, in a contemporary architectural design.