Simplified building models as advanced seismic screening tools for steel industrial buildings

The paper investigates the suitability of simplified building models to be used as advanced screening tools for the seismic vulnerability assessment of older industrial steel buildings. The considered buildings have been built before the enforcement of modern seismic codes and they are characterized by joints with low ductility and by the absence of capacity design provisions. In addition, such buildings, characterized by a wide plan extension, are typically part of large industrial areas. The complex geometry of the buildings makes the creation of a complete finite element model difficult. This is due to the high number of degrees of freedom and to the consequent high number of vibration modes to be included in a general response spectrum analysis. To overcome such limitations, simplified building models for advanced seismic screening are herein proposed and compared to traditional vulnerability procedures. Such procedures may be used for a first estimate of the seismic vulnerability of older and large industrial buildings, in order to identify and quantitatively rank seismic deficiencies before a detailed assessment. The validation shows that the investigated approaches are particularly suitable for seismic risk assessment of building portfolios and for providing a first estimate of the load demand in the elements of the lateral force resisting system.