Steel Buildings in Europe

Part 7: Fire Engineering 7 - 39 a) Doubling of the structure as well as fire walls b) Doubling of structure with fire wall fixed by “fusible” ties c) Example of fire wall inserted into the steel structure Figure 5.15 Some solutions of fire walls Attachment of façade elements and fire walls to steel structure Fire walls and façade elements fixed to steel structure of single-storey- buildings have to remain solidly attached in order to prevent any failure of these elements due to significant lateral displacements of structure in the event of fire, and so to avoid risks of progressive collapse and collapse towards the outside of the building. 3m 3m 3m 3m Fire wall Facade element Figure 5.16 Design detail for façade elements and fire walls One solution consists of fixing these elements to the columns of the load- bearing structure by means of suitable attachment systems uniformly distributed over the building height. The maximum spacing of these attachments will be fixed by the manufacturer of the walls; it is recommended that the spacing should not exceed 3 m for walls constructed on-site walls (concrete, masonry, etc.). In addition, fastenings used to connect fire walls and façade elements on the columns must be designed to resist the forces produced due to wind and self- weight of partition elements under the effect of the lateral displacement induced by the steel frame of the building. If these fastenings are in steel and unprotected against fire, each of them must be designed at ambient temperature to resist the following force: F W p d n i / 5    (34) where: W is the characteristic wind load used for the design at ambient temperature and applied to each fastening [N] p is the self-weight of the wall [N/m²] d is the spacing between frames [m]