This state-of-the-art has been compiled by RILEM TC 109 TSA, Behaviour
of Timber Structures under Seismic Actions. The Technical Committee c
ompleted this work during 1989-1993 and met in Italy, Portugal, Denmar
k, and the United Kingdom. Experience from seismic areas shows that so
me timber houses behave extremely well during earthquakes, but the mec
hanism for the good behaviour has not been fully analysed. Code writer
s have thus not found evidence for timber structures to be characteriz
ed 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 m
aterials 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 req
uirements related to the seismic design of timber houses: the loads, t
he design method including their material input parameters, and test m
ethods to determine these parameters. This is a complex spectrum and i
t was natural to coordinate this with related activities. One Committe
e meeting (in Florence) was therefore arranged in connection with a wo
rkshop for the presentation and discussion of the Eurocode on structur
es in seismic regions. One Committee meeting (in Lisbon) was arranged
jointly with CIB W18, Timber Structures and, finally, one meeting (Lon
don) was arranged in connection with a workshop on the Full-scale Beha
viour of Wood-framed Buildings according to an initiative by Professor
A. Gupta. The meetings of the RILEM Committee have been used to ident
ify 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 pa
pers, but that the different authors have kept the responsibility for
their papers, being passed on in their final versions to the Editor. T
he individual chapters are thus papers which can be read individually
(and minor overlaps or repetitions can be found), but which together g
ive the background for recommending test methods.