BS-5950-part-1-structural-use-of-steel Work REPACK
In this study, two codes of practice are compared: the British Standard (BS 5950)--Part 1 (1990) Structural Use of Steelwork in Building and the American Institute of Steel Construction (AISC) Load and Resistance Factor Design (LRFD, 1986). Steel members such as laterally supported and unsupported beams, concentrically loaded columns, and beam-columns are considered. Only dead and imposed gravity loads are taken into account; the ends of the members are assumed simply supported and standard American sections (W shape) and standard British sections (universal beam and universal column) are used in this paper. A comparison of designs of the various members based on British Standard code 5950 with those based on the AISC LRFD code shows that the latter yields more economical design for most types of members.
Researchers such as Bower (1968), Lawson (1987), Darwin (1990) have stated the presence of web openings may have big drawback on load-carrying capacity of structural members. However, the present design guides and specifications for such beams are either inadequate or difficult to use (SCI P355 2011). This may be due to the fact that the behaviour of I-Beams with web openings is complex to understand, analyse and difficult to simplify the design procedures. Therefore, it is imperative that more elaborate investigations are carried out to provide sufficient information to understand the behaviour so that a simple design method could be developed. A few experimental and analytical studies have been reported in the past regarding SBWOs. For steel beams with circular web openings, most of the design rules are applicable using an equivalent rectangular opening of modified dimensions, as suggested by Redwood (1969). However, due to the simplistic approach, the load-carrying capacities of steel beams are always underestimated significantly. Elastic stress distribution in beams with large circular web openings has been examined by Chan and Redwood (1974) using the theory of elasticity and the curved beam analysis. To assess the load-carrying capacities of steel beams with several circular web openings in an explicit manner, a design method (1990) based on the research works of Olander (1953) and Sahmel (1969) was developed at the Steel Construction Institute in 1990. The method was later incorporated into Amendment A2 of Euro code 3 (EN1993-1-3) Part 1.1: Annex N, in 1998 after minor modification. However, for steel beams with individual circular web openings, the use of a different set of approximate design rules was recommended in Annex N.
Considering all these factors, SBWOs (circular or rectangular) which is one of the suggested possible solutions for integration of technical utilities in buildings were tested up to failure. This study consists of tests on seven models of SBWOs subjected to vertical load as depicted in Figs. 2 and 3. The present work is predominantly experimental oriented, and experiments have been performed on models up to failure. The details regarding the specification of beams like span, type of opening, etc. are given in the Table 1.
The beam having simply supported boundary conditions was set up in the loading frame with sufficient care taken to ensure that the specimen was correctly positioned in the loading frame and the midpoint of the beam was in line with the centre line of the loading hydraulic jack. The specimen was heavily gauged, as shown in Fig. 2, in an attempt to identify a primary mode of failure, i.e. either buckling load for the web post, the formation of plastic hinges, or local buckling of the flange. Prior to application of load on the specimen, all the dial gauges were calibrated properly. Before the actual test, a small preload not exceeding 5 % of the expected ultimate load was applied slowly and removed to eliminate any slack in the support system so that the specimen would be properly seated on the supports. The loading and unloading process was repeated a few times and this procedure also helped to check whether the dial gauges functioned properly. Readings were initialised after ensuring that all instruments worked satisfactorily. The specimen was loaded first up to 20 % of the expected failure load and then unloaded to zero value. It was observed that the deflection readings reached the initial values when unloaded. The procedure was repeated up to 35 % of the expected failure load and the specimen was finally loaded to failure by increasing the load gradually by a predetermined increment. The five dial gauges were installed, three for measurement of vertical deflection placed at L/4, L/2 and 3L/4, respectively, and two for measurement of lateral deflection of top and bottom flange, respectively, as shown in Fig. 2. The beam was then tested to failure. After the maximum load was attained and unloading occurred with increase in beam deflection, the load was then removed. The ultimate load and the mode of failure for each of the specimens were noted. The same test procedure was adopted for all the specimens.
This text aims to develop an understanding of Limit State Design as applied to structural steelwork. The use of the relevant codes of practice, in particular BS 5950: Part 1, is explained and demonstrated in numerous worked examples and illustrations. The treatment is both extensive and comprehensive, including a selection of design examples which are presented in a format typical of that used in a design office in order to encourage students to adopt a methodical and rational approach in preparing structural calculations.
Morris Fabrications Ltd are an experienced architectural metalwork company based in Birmingham. We are able to manufacture and install various architectural metalwork including staircases, fire escapes, galvanised steel staircases, access ladders, stainless steel balustrade, mild steel balustrade, frameless glass balustrade, juliette balconies, steelwork plus much more. Call us today on 0121 772 0801.
List of Superseded British Standards that are to be withdrawn on 31 March 2010: Loading for buildings BS 6399-1:1996 Loading for buildings. Code of practice for dead and imposed loads Superseded by EN 1991 BS 6399-2:1997 Loading for buildings. Code of practice for wind loads Superseded by EN 1991 BS 6399-3:1988 Loading for buildings. Code of practice for imposed roof loads Superseded by EN 1991 Structural use of concrete BS 8110-1:1997 Structural use of concrete. Code of practice for design and construction Superseded by EN 1992 BS 8110-2:1985 Structural use of concrete. Code of practice for special circumstances Superseded by EN 1992 BS 8110-3:1985 Structural use of concrete. Design charts for singly reinforced beams, doubly reinforced beams and rectangular columns Superseded by EN 1992 BS 8007: 1987 Code of practice for design of concrete structures for retaining aqueous liquids Superseded by EN 1992 Structural use of steel BS 5950-1:2000 Structural use of steelwork in building. Code of practice for design. Rolled and welded sections Superseded by EN 1993 BS 5950-2:2001 Structural use of steelwork in building. Specification for materials, fabrication and erection. Rolled and welded sections Superseded by EN 1994 BS 5950-3.1:1990 Structural use of steelwork in building. Design in composite construction. Code of practice for design of simple and continuous composite beams Superseded by EN 1994 BS 5950-4:1994 Structural use of steelwork in building. Code of practice for design of composite slabs with profiled steel sheeting Superseded by EN 1994 BS 5950-5:1998 Structural use of steelwork in building. Code of practice for design of cold formed thin gauge sections Superseded by EN 1993 041b061a72