TIMBER STRUCTURES IN SEISMIC REGIONS - RILEM STATE-OF-THE-ART REPORT

This state-of-the-art has been compiled by RILEM TC 109 TSA, Behaviour of Timber Structures under Seismic Actions. The Technical Committee completed this work during 1989-1993 and met in Italy, Portugal, Denmark, and the United Kingdom. Experience from seismic areas shows that some timber houses behave extremely well during earthquakes, but the mechanism for the good behaviour has not been fully analysed. Code writers have thus not found evidence for timber structures to be characterized in general as behaving well. Therefore, the main aim of the work of the Committee was to improve the information on wood and wood-based materials for the design of structures exposed to seismic loading. This includes the identification of adequate test methods. To achieve the main objectives it was necessary to look into the wide spectrum of requirements related to the seismic design of timber houses: the loads, the design method including their material input parameters, and test methods to determine these parameters. This is a complex spectrum and it was natural to coordinate this with related activities. One Committee meeting (in Florence) was therefore arranged in connection with a workshop for the presentation and discussion of the Eurocode on structures in seismic regions. One Committee meeting (in Lisbon) was arranged jointly with CIB W18, Timber Structures and, finally, one meeting (London) was arranged in connection with a workshop on the Full-scale Behaviour of Wood-framed Buildings according to an initiative by Professor A. Gupta. The meetings of the RILEM Committee have been used to identify specific tasks of interest and to discuss drafts presented to the Committee. Volunteers were found to draft the different chapters. This means that the Committee has influenced the scope and the specific papers, but that the different authors have kept the responsibility for their papers, being passed on in their final versions to the Editor. The individual chapters are thus papers which can be read individually (and minor overlaps or repetitions can be found), but which together give the background for recommending test methods.