Seismic performance of traditional half-timbered walls : experimental results

Abstract

Half-timbered structures constitute an important cultural heritage of many countries, since they represent a typical anti-seismic construction adopted worldwide [1][2]; therefore, their preservation is of the utmost importance. Although recent earthquakes have pointed out the good seismic behaviour of this kind of structures, few experimental studies are available on the performance of traditional half-timbered walls and their retrofitting solutions and mainly only qualitative information is available of the seismic response of such structures. Due to this lack of information, an extensive experimental campaign was carried out, performing in-plane cyclic tests on real scale half-timbered and timber frame walls, adopting connections and dimensions encountered in real structures and considering different infill types (brick masonry and lath and plaster). Moreover, keeping in mind the great rehabilitation effort that has been carried out in recent years on such buildings, such in the case of the Portuguese Pombalino buildings in Lisbon, it is important to study the effect of strengthening on traditional timber-frame walls. To do this, retrofitting solutions have been applied to traditional walls and tested under cyclic loading. Both traditional and innovative techniques have been considered, namely bolts, steel plates and NSM steel flat bars. Results on the behaviour of both unreinforced and retrofitted walls are analysed and their seismic behaviour is discussed.