Prospects of seismic upgrading a weak r.c. school building using light gauge steel walls

Significant number of reinforced concrete building frames executed in the '50's-60's in Europe need seismic upgrading. At those times understanding of earthquake effects was insufficient and quality control on construction sites lacking. This combination resulted in buildings framed in reinforced concrete with bad quality materials and inadequate reinforcement. The low-medium rise buildings often house public functions today. In this paper, we analyze the potentials and limitations of using light prefabricated steel wall systems (LGSW) to upgrade frames to higher seismic standard. Results show that r.c. frames with virtually no seismic resistance (PGA~0.05·g) can be upgraded to resist intermediate earthquakes, possibly up to PGA~0.2·g. The LGSW's have remarkable flexibility to adapt to the refurbishment requirements in terms of stiffness and strength, and also provide adequate ductility.