PSI - Issue 78

Leonardo Casali et al. / Procedia Structural Integrity 78 (2026) 1269–1276

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therefore "staged construction" analyses have been carried out. The following phases have been considered: (1) initialization of the structure without both braces and "sickles" (all beam-column joints have hinge-type connections, longitudinally as well as transversely); (2) application of structure and floors dead loads; (3) insertion of connecting elements (based on "crescent" devices) and bracing elements; (4) application of the remaining static loads; (5) seismic analysis by modal analysis with response spectrum; (6) safety checks (resistance, deformation, stability, etc.) for the relevant load combinations.

Fig. 8 Axonometric views of the calculation model of Block A of PM3 building.

All the relevant loads applied to the structure have been considered and assigned to the numerical model. In particular, with regard to service loads, different categories of loads were considered in reference to the different intended uses of different areas of the construction. Fig. 9 shows, for Block A, an example of the different service loads, identified accordingly with a colour-based legend, with their dislocation at different levels, values and combination (partial safety) coefficients.

Fig. 9 Block A: loads on decks +7,00 (left) and +13,50 m (centre); legend of the loads (right).

Another particular type of load is that represented by the static and dynamic loads applied by overhead cranes. In the case in question, two overhead cranes, 100 and 70 tons, are present on the same rails and it is necessary to adopt a criterion to consider the worst load condition since, being in conflict, it is not possible to consider a condition of mobile loads. The actions due to the two overhead cranes running on the same line were applied on two consecutive column alignments. On one alignment the actions associated with the 100 t overhead crane and, on the next, those associated with the 70 t one. With reference to the transverse cross section of the building, the maximum forces were applied on one rail and the minimum forces on the other rail. The applied forces were determined as the sum of the actions acting on the 4 wheels on one side of the overhead crane, also taking into consideration the dynamic increases. The choice of columns to load was made for having the maximum eccentricity of the loads.