Steel Buildings in Europe

Part 4: Detailed Design 4 – 20 4 SERVICEABILITY LIMIT STATE 4.1 General EN 1990 [5] , § 3.4 and 6.5 and EN 1993-1-1 [1] , § 7 require structures to satisfy the Serviceability Limit State. Criteria relevant to multi-storey buildings are:  Horizontal deflections  Vertical deflections on floor systems  Dynamic response. The general philosophy of the Eurocodes is not to offer prescribed general limits for horizontal and vertical deflections, but to recommend that limits should be specified for each project and agreed with the client. They acknowledge that National Annexes may specify relevant limits for general applications in specific countries. Sections 4.3 and 4.4 provide the definition of horizontal and vertical deflections and suggest some limits, based on Access Steel document SN034a [4] . 4.2 Load combinations As discussed in Multi-storey steel buildings. Part 3: Actions [6] , different combinations of actions are used for serviceability and ultimate limit states. It is noteworthy that some countries only apply limits to response to variable actions (i.e. deflections due to permanent actions are not limited). 4.3 Horizontal deflection limits The definitions of horizontal deflections in Annex A1 to EN 1990 [5] are shown in Figure 4.10. Table 4.1 summarises typical horizontal deflection limits used in Europe.