Structure and architecture: the illogical results of considering them two separates entities, after the 2009 earthquake in L'Aquila

The paper examine, through a series of examples, what happened in L'Aquila after the earthquake of April 2009. The state of emergency and the immediate need of checking the buildings safeness, accomplished through the detection of structural damage, started a research and operational implications directed only towards structural problems, as if they could express the 'full knowledge' of architectural episodes in all their distinctive features (construction history, stratigraphic analysis of construction, study of building materials and degradation, etc.). The lack of understanding of historical architecture and of its value has entailed some questionable actions either in terms of 'first emergency' operations or of 'safety' operations or repair of damage. A clear separation between 'structure' and 'architecture' is an utopia generally difficult to pursue but, in particular, it cannot be applied in the field of historic architecture, which has been built with materials and techniques that make it impractical to distinguish the one from the other. The experience of the 2009 earthquake showed that during the emergency stage, many decisions gave precedence to structural concerns and that even while the remaining structures were being made safe, very often interventions showed scant regard for items of historical architecture and their decorative aspects (the full paper shows some examples). On the other hand, observations of earthquake damage, when carried out with proper awareness of the building's construction history, have shown that, in the case of historical architecture, damage is not always caused by structural instability, but instead often exhibits discontinuities owing to different construction phases, or repairs carried out following previous earthquakes. The city's earthquake history, in fact, shows that almost all historical buildings have undergone previous post-seismic repairs and rebuilding, and that the latter in particular has used surviving structures as much as possible by reinforcing them in a more or less effective manner. The dynamic stresses produced by the latest earthquake have revealed such discontinuities everywhere. These do not in themselves result in a vulnerability of the building. However it is opportune to bear them in mind so as to avoid erroneous interpretations during subsequent diagnostic and planning phases. Moreover, the recent Guidelines for evaluation and mitigation of seismic risk to Cultural Heritage (Cultural Heritage Ministry, Italy 2006) intend to combine the quantitative method of numerical tests with a critical-descriptive approach to architectural study, with the aim of finding the right mix in the delicate synthesis of conservation and safety of built cultural heritage.