Proposal of an Analytical-Experimental Procedure for Determining the q-Factor of Timber Building Systems

The paper analyzes the definition of the q-factor in the literature and its relevance in design of structures in seismic areas. The available methods for estimating the q-factor are based on the verification of the non-linear seismic response of entire buildings by means of experimental full scale shaking table tests or numerical simulations. These procedures result very expansive both from the economic and computational point of view. This work proposes a new procedure for the q-factor evaluation based on a proper application of the pushover method to the loaddisplacement curve obtained through experimental quasi static tests on representative wall elements. Such procedure is validated through shaking table tests and numerical simulations on CLT building systems. An extensive application of the proposed procedure to a number of wooden building system tested in the CNRIVALSA laboratory is presented in order to carry out a reliable estimation of the q-factors. Finally the main advantages and limitations of the proposed procedure are presented and critically discussed.