This study was developed within a research project concerning the seismic vulnerability assessment of precast industrial buildings built in Italy in the 1970s without earthquake-resistant provisions. Two reference precast buildings with beam-to-column connections based on neoprene-concrete friction strength were considered. Accurate numerical models of the existing buildings were developed and nonlinear dynamic time-history analyses with different seismic intensity levels were carried out in order to identify the main causes of structural collapse. The maximum values of the demand-to-capacity ratio in terms of chord rotation were computed for the columns of the investigated precast buildings. The capacity was larger than the demand, even in case of high levels of seismic excitation. Numerical results showed that existing precast industrial buildings can collapse due to beam-to-column connection failure for loss of support, confirming real events observed during recent earthquakes. The friction resistance was exceeded under moderate-to-severe seismic actions at the corner columns where the static vertical load was lower. Numerical analyses highlighted the detrimental effects of the vertical component of the seismic action on the likelihood of the occurrence of beam-to-column connection failure due to loss of support.
Seismic vulnerability assessment of RC buildings with setback irregularity
