Retrofit solutions conceived to have low-invasiveness, rapidity of execution and seismic capacity enhancement are of paramount importance in the perspective of Performance-Based Retrofit. Among the various retrofit techniques developed for existing reinforced concrete buildings, those based on the use of external additive walls seem to better satisfy such prerequisites.
This paper deals with a preliminary numerical study aimed at investigating the benefits provided by external post-tensioned rocking Cross-Laminated Timber (CLT) walls to an existing six-storey reinforced concrete building. To this aim, a design methodology based on the Displacement-Based Design which allows to determines the wall dimensions and the pre-stressing forces in the tendons has been herein proposed.
The effectiveness of the additional rocking CLT walls have been validated trough nonlinear static analyses, conducted on both as-built and retrofitted structure. Preliminary results, show that the retrofit intervention is beneficial in terms of seismic capacity increase, expected annual losses and reduction of the seismic risk class of the construction. Nevertheless, future studies based on a more accurate modelling are necessary to validate the results herein obtained and for defining technological solution the connections between framed structure and CLT walls.
