Steel Buildings in Europe

Part 4: Detailed Design 4 – 1 1 INTRODUCTION 1.1 General In this publication, medium rise steel frames are defined as frames where neither resistance to horizontal loads, nor achieving sufficient sway stability has significant impact on either the plan arrangement of the floors or the overall structural form. This limit is normally regarded as twelve storeys. Low rise buildings (of two or three storeys) are only subject to modest horizontal forces and may readily be conceived with robust bracing systems such that second order effects are minimised, to the extent that sway stability effects need not be considered explicitly in design. The bracing may be provided either by triangulated bracing or by reinforced concrete core(s); the floors act as diaphragms to tie all columns into the bracing or cores. 1.2 Scope of this document This document guides the designer through all the steps involved in the detailed design of braced multi-storey frames to EN 1993 [1] and EN 1994 [2] . It focuses on the application of ‘simple construction’ as the way of achieving the most economic form of construction. Coincidently, and very conveniently, these approaches also are the simplest to use in the design office, thereby minimising design office costs. The guide addresses:  The basic concept of simple construction  Guidance on the global analysis of frames for simple construction  Design checks at the Serviceability Limit State (SLS)  Design checks for the Ultimate Limit State (ULS): floor systems, columns, vertical and horizontal bracing  Checks to ensure the structure has sufficient robustness to resist both specified and unspecified accidental loads.