Steel Buildings in Europe

Part 3: Actions 3 - 10 6 IMPOSED LOADS 6.1 General Generally, imposed loads on buildings shall be classified as variable free actions. They arise from occupancy. They include normal use by persons, furniture and moveable objects, vehicles, anticipating rare events (concentrations of persons or of furniture, momentary moving or stacking of objects, etc.). Movable partitions should be treated as imposed loads. Imposed loads are represented by uniformly distributed loads, line loads or point loads applied on roofs or floors, or a combination of these loads. Floor and roof areas in buildings are sub-divided into categories according to their use (Table 6.1). The characteristic values q k (uniformly distributed load) and Q k (concentred load) related to these categories are specified in Table 6.2 (or in the National Annex). For the design of a single floor or a roof, the imposed load shall be taken into account as a free action applied at the most unfavourable part of the influence area of the action effects considered. Where the loads on other storeys are relevant, they may be assumed to be distributed uniformly (fixed actions). Characteristic values of imposed loads are specified in EN 1991-1-1 Section 6.3 as follows: 6.3.1 Residential, social, commercial and administration areas 6.3.2 Areas for storage and industrial activities 6.3.3 Garages and vehicle traffic areas 6.3.4 Roofs. 6.2 Reduction due to the loaded area In multi-storey buildings, the characteristic value q k of the imposed loads on floors and accessible roofs may be reduced by a factor  A , for categories A to D, where:  A = 1,0 7 5 0 0   A A  With the restriction for categories C and D:  A ≥ 0,6 where:  0 is the factor as defined in EN 1990 Annex A1 Table A1.1.  0 = 10 m 2 A is the loaded area The National Annex may give an alternative method.