Italian rules about fire fighting in civil engineering are finalized to the obtainment of a certificate (the so-called CPI – Certificato di Prevenzione Incendi) emitted by the Italian Fire Fighters Departments (VVF – Vigili del Fuoco).
Accordingly to the relative law in force (Decreto del Ministero dell’Interno 9 marzo 2007) the obtainment of the CPI can be accomplished by following two different approaches which common aim is to determine the fire strength of buildings as R.E.I. classification.
The first approach is of analytical type and leads to the calculation of the R.E.I. class of the building by means of coefficients and standard range values. This kind of approach is typically conservative.
The second one is related to the real fire performances of the building and it is carried on by a thermo-structural verification: after the choice of the more probable fire scenarios, the relative natural fire curves allow to carry out the structural verification of the building. The natural fire curves can be drawn from experimental data or by simple/advanced numerical fire models. In this case, which regards the obtainment of the CPI for the LIDL’s warehouse of Pontedera-Pisa (accordingly the performance approach), it was used an advanced numerical fire model implemented in the fluid-dynamic code FDS (Fire Dynamic Simulator, NIST) in order to obtain a temperature map (natural fire curve) as input for the structural verification performed by Concrete ThermoCAD on the warehouse pillars and beams.
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