Response Spectrum Analysis of light timber-frame buildings by means of an iterative approach

: Light timber-frame buildings are nowadays widely spread even in seismic prone regions tanks to several researches undertaken in the last decade, which highlighted their potentialities in terms of seismic response. Anyway, a definitive method to assess their dynamic properties as well as an analytical method to apply the Response Spectrum Analysis (RSA) are missing both in standards and literature. The present paper deals with the seismic analysis of this type of building. Specifically, through the use of a numerical simplified model accounting for the main deformation contributions, three analytical-iterative method to apply the RSA are presented. The methods are iterative because both of the hold-downs behaviour and the vertical load actions. In fact, the hold-downs display an on-off behaviour depending on their state which can be active (hold-down in tension) or not active (hold-down not in tension), whereas the vertical load modifies the seismic force distribution within the wall. These methods can be used to assess the dynamic properties of a building and to design non-regular buildings. In order to allow readers to better understand the procedures a numerical example is included.