Page 57 - Building Regulation and Design Guidelines - Structural (Grey Code)

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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