Page 57 - Building Regulation and Design Guidelines - Structural (Grey Code)
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SECTION: 4  STRUCTURAL DESIGN GUIDELINES - STEEL STRUCTURES                           SECTION: 4  STRUCTURAL DESIGN GUIDELINES - STEEL STRUCTURES




                     performance criteria given in guidelines for building structures shall be referred             d.   Fracture due to fatigue and brittle fracture.
                     to and the relevant sections shall be considered in the design.
                                                                                                                    e.   Corrosion and durability.
                     4.3.1   GENERAL                                                                           10.   Details of members and connections should be such as to realize
                          1.   Minimum design life of the steel structure shall be 50 years unless                   the assumption made in design with out affecting any other part
                               otherwise specified.                                                                  of structure.
                          2.   The aim of structural design should be to provide, with due regard         4.3.2   LOADING
                               to economy, a structure capable of fulfilling its intended function
                               and sustaining the specified loads for its intended life.                        All relevant loads should be considered separately and in such realistic
                                                                                                                combinations as to comprise the most critical effects on the elements and
                          3.   The design should facilitate safe fabrication, transport, handling               the structure as a whole.
                               and erection. It should also take account of the needs of future                 1.   Dynamic  loads  shall  be  considered  for  cranes  and  for
                               maintenance, final demolition, recycling and reuse of materials.
                                                                                                                     members supporting machineries as per the manufacturer’s
                          4.   The structure should be designed to behave as a one three                             recommendations and as per the applicable codes.
                               dimensional entity. The layout of its constituent parts, such as
                               foundations, steelwork, joints and other structural components                   2.   Temperature effects shall be included in the design of the structure
                                                                                                                     including temperature effects during erection stage, operational
                               should constitute a robust and stable structure under normal                          aspect, etc.
                               loading to ensure that, in the event of misuse or accident, damage
                               will not be disproportionate to the cause.                                 4.3.3   LIMIT STATE OF STRENGTH
                          5.   The  basic  anatomy  of  the  structure  by which the  loads are                 In checking the strength and stability of the structure all loads shall be
                               transmitted to the foundations should be clearly defined.                        multiplied by the applicable load factors and all combinations of loads
                          6.   Any features of the structure that have a critical influence on its              producing the worst effects on the structure and its constituent elements
                               overall stability should be identified and taken account of in the               shall be identified and used in the strength limit state design. Load
                               design.                                                                          factors and combinations given in Table 1 below shall be used when BS
                                                                                                                5950 is adopted for design.
                          7.   Each part of the structure should be sufficiently robust and
                               insensitive to the effects of minor incidental loads applied during              1.   Factors and combinations shall be used consistently throughout
                               service that the safety of other parts is not prejudiced.                             the project as per the design code adopted. Mixing factors and
                                                                                                                     combinations from different codes are not allowed.
                          8.   The design intention should be to adopt a layout so as to rationalize
                               the  use  of  member  sizes  and  details  to  achieve  maximum
                               structural efficiency and to obtain a combination of materials
                               and workmanship consistent with the overall requirements of the
                               structure.
                          9.   Design shall include all limit states in addition to the limit states of
                               strength and serviceability as follows:
                               a.   Strength limit states including general yielding, rupture,
                                   yielding, buckling and transformation into a mechanism.
                               b.   Serviceability limit states
                               c.   Stability against overturning & sway.

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