In the first part of this thesis, a risk-targeted decision model for the verification of the seismic performance of a single industrial unit is presented. It includes the assessment of the seismic demand for a design earthquake and the seismic capacity, which is reduced by a risk-targeted safety factor. Such a safety factor implicitly guarantees the desired performance of the unit with a predefined target (acceptable) risk. The proposed risk-targeted decision model is similar to the code-based approach, which is familiar to engineers. However, it does not solve the issue of the definition of target risk for the units of an industrial facility. For this reason, the seismic design parameters for the units of an industrial facility should be evaluated for a tolerable risk considering the entire industrialised urban area, as introduced in the second part of the thesis. The proposed methodology comprises five processes: (1) fatality analysis with consideration of domino effects (e.g. fires, explosions, toxic dispersions); (2) population analysis to simulate the spatial and temporal variability of the distribution of people in the area; (3) seismic hazard analysis for the location; (4) definition of the tolerable risk in terms of the annual number of fatalities and (5) iterative adjustment of target fragility function of the industrial units. The last process comprises the disaggregation of the fatality risk, which provides useful information about the most critical units. The capability of the new framework for the risk-targeted design of units of an industrial facility is demonstrated by means of examples. It is shown that the domino effects can have a significant impact on the fatality risk. Moreover, the target seismic fragility functions of industrial units can vary significantly if the performance objective is defined by the fatality risk of the entire industrialised urban area.
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