Earthquake, urban form and city planning: research perspectives

The study on the seismic vulnerability of cities and urban fabrics, referring to the susceptibility to the loss of a city's organization during an earthquake, has become a scientific field which for some time now has acquired own particular specificity, and which involves different research lines and experimentations in the broad area of the sciences on the relationship between earthquakes and human settlements. This is due to several different reasons. Firstly, building vulnerability in a settlement and the intrinsic vulnerability of the urban structure have been considered for a while to be closely inter-dependent and complementary, and that the appropriate approach to their study should begin from basic hypotheses and concepts which are quite different. In particular, the studies on a town's seismic vulnerability mainly depend on a series of factors directly linked to the different underlying content and approaches which are, in fact, from a different point of view, the features of the urban-planning discipline. These factors are mainly linked to the concepts of urban structure and urban fabric, concepts which have always been of key importance in the study and design of urban form. Concerning the above, at the present moment in Italy, some principal fields of experimentation and research can be identified, regarding the relationship between earthquakes and towns. The aim of this paper is to present an overview of the main points of the most important of the research lines, briefly discussing their respective content and specific features. Therefore, a brief but specific detailed study will be made, based on a “field” experience currently being carried out in the town of Bevagna in the Umbria region. It is a case where the seismic vulnerability study of a town is being conducted simultaneously with a study regarding the appropriate integrating of urban-planning and regional tools. Finally, some important development and research lines will be outlined, where specific perspectives for refining the studies and tools will be highlighted.