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Deep renovation interventions on existing buildings remain currently unattractive due  to  technical,  financial  and  cultural/social  barriers.  Now  that  the  European  Union  2018 Energy Performance Directive aims to “reach the long-term greenhouse gas emission goal and decarbonize the building stock”, Member States may use their long-term renovation strategies to address risks also related to fire hazards and seismic loads in addition to energy renovation. This opens a wider market for innovative approaches in retrofit of existing buildings. 

The current paper illustrates the primary outcomes of an ongoing multidisciplinary Horizon 2020  research  project  (called  e-SAFE),  tackling  the  integration  of  energy,  seismic  and  architectural  renovation  interventions  through  an  innovative  and  combinable  technological  solution,  applicable to  non-historic  RC  framed  buildings  (i.e.  built  after  1950)  and  easily  adaptable  to  specific  climatic  conditions,  seismicity  levels  and  other  boundary  conditions.  Hence, the proposed solution will contribute to the de-carbonization of the EU building stock, reducing the occurrence of natural hazards related to climate changes, and, at the same time, to  the  improvement  of  the  social  resilience  against  earthquakes  and  to  the  enhancement  of  buildings architectural image.  

The seismic retrofit technology consists in the external application of modular prefabricated Cross  Laminated  Timber  (CLT)  panels  on  the  existing  perimetral  walls.  These  panels  are  connected to  the  beams  of  two  consecutive  floors  by  means  of  friction  dampers  and  provide additional lateral stiffness and strength to the existing structure, thus reducing the storey drift demand in case of earthquake. The friction dampers cut the force transmitted by the CLT panel to the structure and dissipate energy, which further reduce the drift demand. Strength, stiffness and dissipation capacity provided by the system are controlled by modulating the thickness and the number of CLT panels, as well as the friction dampers size. 

In this research phase, friction damper prototypes have been designed in order to optimize  both mechanical performance and production process. Detailed numerical models allowed to investigate the stress distribution in the dissipative connections. The results of the preliminary testing campaign will be presented and discussed in this paper, also in relation with the findings of the numerical analysis and future tests.

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== Full document ==

<pdf>Media:Draft_Content_703446386p1196.pdf</pdf>

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