Experimental tests for the evaluation of the seismic performance of the innovative CFS wall

Lightweight Steel (LWS) systems made of Cold-Formed Steel (CFS) represent a suitable solution for structural systems combining the lightness of the construction with high structural performance under seismic actions. However, till now their structural application in high seismicity areas is still limited. In this framework, the ECCLSA research project was developed to investigate both the structural and thermal performance of an innovative LWS wall lateral force resisting system (LFRS) designed for application in low, moderate and high seismic areas. The introduced system is made by a CFS wall in conjunction with a V-braced system equipped with pre-tensioned Ultra-High-Strength (UHS) steel bars. A design procedure, as well as a large experimental campaign, were conducted to investigate both global and local performance of the introduced wall LFRS. In particular, coupon and relaxation tests were performed to investigate the main material features, while both monotonic and cyclic tests were performed on the whole system. The results show that, if well designed, the introduced LFRS system is able to counter seismic loads concentrating all the plastic deformation within the ultra-high strength bar, leaving in elastic range all the other elements.