The city when it trembles. Earthquake destructions, post-earthquake reconstructions and grid configuration

Two different (yet tightly connected and complementary) wide issues appear to crisscross in this research. The first one is the general question of urban resilience, assumed in its relational meaning: the capacity of an urban system, thanks to the features of its spatial elements, to take abruptly imposed transformations, without significantly changing their mutual relations and hence the whole urban geography: and the transformation imposed by an earthquake (its destruction as well as the successive reconstruction) are undoubtedly sudden and abrupt. A discussion will hence be aimed at determining some configurational parameters, suitable for reproducing the capability of a spatial system to sustain sudden changes and yet to retain its inner working mechanisms. The second theme more specifically concerns the matter of earthquakes, and will here be aimed at investigating the effect of a seismic event on the inner geography of an urban settlement, thus verifying on several case studies the effects of an earthquake as well as the reliability of space syntax to describe their actual resilience. Summing all up, this paper aims at pinpointing the configurational features, if any, suitable for reproducing and accounting for the level of resilience a settlement is provided with, and - afterwards - at testing them on urban cases actually affected by earthquake destructions. The main case study here assumed is the settlement of L’Aquila, in Italy, with reference to the devastating earthquake of April, 6th 2009. The configuration analysis has been applied to the spatial consistencies respectively referred to three distinct phases: - beforetheearthquake; - soonaftertheearthquake(temporary,butstillpresentsituation); - after the earthquake, definitive (yet distant to come) situation, including the forthcoming reconstruction of the perished areas and the new development areas (at L’Aquila, the so-called ‘CASE’ project). Some significant outcome can be drawn. First, this approach allows highlighting the dramatic transformation an earthquake, like other natural disasters, is likely to cause to the inner geography of a settlement, upsetting the distribution of movement flows and the levels of attractiveness and centrality. Even more, the configurational analysis will reveal the likely effects the reconstruction and rehabilitation plans and projects on the variables of the urban system, over and above the fulfilment of recovery claim and the housing supplying. More in general, it will report the far-reaching and long-lasting relevance of urban plans worked out in emergency situation, under the pressure of need and urgency. On such basis, the method is here proposed as a suitable tool for supporting and orienting the temporary (yet often enduring) post-earthquake phase as well as the successive reconstruction planning.