INFERRING SEISMIC BEHAVIOR FROM MORPHOLOGYIN TIMBER ROOFS

Timber roof structures composed with parallel trusses are used in traditional buildings in a variety of forms and sizes. The effect of structural morphology on the seismic response of these structures has been investigated with the aim at defining criteria for assessing their seismic vulnerability. Classic modal and response spectrum analyses have been performed considering natural periods, stress levels, and displacements in order to define vulnerability classes associated to the main structural parameters. Results have shown that the empirical sizing rules of the constructional tradition correctly combine span lengths, minimum cross section sizes and structural layout also in view of a dynamic response. Considering that vulnerability assessment methods are based on visual inspection and synthetic judgment, the same results have brought to define classes of vulnerability, by which structures may be classified on the basis of geometric dimensions and data observable by direct inspection.