Multi-risk can be considered as superposition of various hazards, e.g. technical hazards, man made hazards, natural hazards.
Challenges of multi-risk approaches:
-multi-hazard and multi-risk approaches are usually not appieda, only some exceptions
-multi-risk considerations as scientific approach, not yet applied to practice
-different details of data and different parameters
-difficult to apply to all spatial levels from regional to local
-diverse responsabilities of sectoral planning divisions for different natural hazards
Need for multi-risk approaches:
-most European regions are characterized by the presence of multiple natural and technological risk by spatial planning remainder a major challenge
-decision makers need comprehansive comparabile information which includes all relevant hazards types within a region
-quantitative comparisons of hazard assessment results are difficult due to different parameters, thus the multi-hazard approach has to be enlarged by the multi-risk approach
Fires following earthquakes are considered one major threat in seismic regions. In fact, according to modern seismic codes,ordinary structures are designed to suffer damage to some extent during strong earthquakes, exploiting the structure own ductility to avoid collapse and safeguard human lives. Then, a fire coming after an earthquake will find a different, more vulnerable, structure with respect to the initial, undamaged, one.
Related paper: “Risk assessment of steel structures under fire”.
The dissertation, supervised by prof. Franco Bontempi, of my graduation exam was: “Valutazione dell’influenza del danno sismico sulla resistenza al fuoco di strutture in acciaio (Fire resistance assessment of steel framed structures damaged by seismic actions)”. The study assumed a simplified schematisation of seismic damage, which is convenient to be used for parametric analyses. Accordingly, two forms of seismic damage have been stated: geometrical and mechanical damage. So define a method to quantify the reduction of fire resistence of simple steel structures due to geometrical and mechanical seismic damages.