Specification for structural steels

Weldable structural steels are defined by British Standards BS EN 10 113, and BS EN 10 025, which are now the UK issues of European standards for steel as a structural material. These standards replace BS 4360, in which the most common grades were 43A and 50B, referring to the ultimate tensile strength of the steel, i.e. 430 and 500 N mm respectively. A and B refer to the toughness characteristics of the steel, which are relevant to the limit temperature at which the steel is used in service....

Arched triangular lattice grid

One system which, up to now, has remained at the concept stage is an arched triangular lattice grid proposed in the competition winning design for the athletic stadium in Frankfurt, by Foster and Partners (see Figure 8.8). The arch roof shape was chosen and the supporting framework was conceived as a triangular plan grid that offset the longer route of arching forces with the provision of more frequent-braced points. It was manufactured as a series of identical prefabricated units in the form...

Pinned connection

Sttel Construction Architecture

A conventional pinned detail of a bar to a plate is illustrated in Figure 7.14. These connections can be designed to emphasise the 'pin' form by using flatter coupling and larger 'pins'. Corrosion protection of the connection may be achieved by over-painting the connection, by sealing it, or by using stainless steel pins. The latter only solves the problem of corrosion of the pin and neglects the plate and fork. There may also be a problem of bimetallic corrosion between steel and stainless...

Vertical bracing

The stability of the building is dependent on the form and location of the vertical bracing, or other shear-resisting elements which are linked by floors or horizontal bracing. For simplicity, vertical bracing is located in the fa ade or internal separating walls. Ideally, the bracing line would be on the centre-line of the main columns, but this may conflict with the location of the inner skin of external walls. Discussion between the architect and the structural engineer at an early stage can...

Proprietary bar and cable linking details

Millennium Dome Construction Details

A number of manufacturers produce cables with swaged (pressed) ends and with galvanized or stainless steel fittings. A typical 7.25 Threaded end to permit adjustment swaged termination with an adjustable fork-end is illustrated in Figure 7.21. Swaged fork-ends provide a slim and effective way of terminating a cable and bars, and provide a simple pin connection. The cable is anchored into the back of the fork using the swaging process, providing a neat and strong end. The fork end is simply...

Opportunity for architectural expression

Renault Distribution Centre Structure

Steelwork possesses various advantages for architectural expression, as follows External structures clearly express their function. Slender members can be designed efficiently, particularly using tubular sections. 'Lightness' can be accentuated by openings in beams and by latticework in the form of trusses. Curved members, such as arches, can be formed easily. Tension structures are efficient and lightweight, particularly for long-span enclosures. Connections can be designed expressively. The...

Connections between Isections

Bolted Connection Inclination

In a typical steel structure, the detailed design of the connections, the preparation of the production drawings, the fabrication and the erection accounts for some two-thirds of the total cost of the framework. Most of the cost is absorbed in the detailing and fabrication of the connections between the members. In most projects, steel fabricators undertake the design and detailing of all connections according to their preferred method of fabrication. Because of this, there has tended to be a...

Water filling of tubular sections

Curved Solar Panels Prototype

Water filling is often mentioned as a method of providing fire resistance to tubular structures, but is rarely carried out in practice. The earliest and most well-known example is the external structure to Bush Lane House in Cannon Street, London (see Figure 13.6). At the new Cargo Handling Facility of Hong Kong Airport, the long-span tubular trusses were water filled to provide 120 minutes' fire resistance, and the prototype trusses were fire tested to prove their effective performance. These...

Welded hollow sections

Welded hollow sections can be produced by a number of different methods. The most common is known as the conversion method in which round hollow sections are produced and then converted to the required shape by re-rolling. The welding can be carried out by butt or continuous welding, electric weld, spiral weld, and submerged arc welding. A method used less commonly in the UK, but more extensively in the United States and Japan, is the direct or brake press method in which the rectangular or...

Portalframe structures

Glas Architecture Frame Structure Corner

Portal-frame type structures are examples of rigid frames that can take a number of forms. They were first developed in the 1960s, and have now become the most common form of enclosure for spans of 20 to 60 m. Portal frames are generally fabricated from hot-rolled sections, although they may be formed from lattice or fabricated girders. They are braced conventionally in the orthogonal direction. In general, portal-frame structures are used in single-storey industrial type buildings where the...

Connections between tubular sections

Connections between tubular sections are fundamentally different from those between open sections, such as I- and L-sections. There are two principal forms of connection bolted and welded, but even bolted connections generally contain welded parts. In designing tubular structures using circular (CHS), square (SHS) or rectangular hollow sections (RHS), it is important that the connection design is considered at the start of the design process, as this can have a strong influence on the...

Common protection systems

The protection systems detailed in this section (see Tables 12.2 and 12.3) are based on those which are currently recommended by Corus for various environments. The system numbers are those allocated by Corus and the recommended paint thicknesses are the dry film thickness. These thicknesses may vary between manufacturers. Systems have been chosen which are suitable for the following environments low risk where there is a low risk of condensation, exhibition halls, workshops, sports halls...

Curved beams

Structural Properties Cellular Beams

Steel members of any standard section can be supplied curved to a constant radius. This is a specialised technique, and advice should be sought on the appropriate bending radii relative to the section which is proposed to be curved. The minimum radius to which any section can be curved depends on the metallurgical properties of the steel and particularly its ductility, cross-sectional geometry and its end use. Examples of curved beams used in roofs and canopies are illustrated in Figures 4.13...

Tension structures

In tension structures, 'ties' are designed to resist only tension and are crucial elements in the overall structural concept. Tall compression members or 'masts' provide for the necessary vertical support, and these masts are located fully or partially outside the enclosure. Cable-stayed roofs, suspended structures, cable nets and membrane structures are all types of tension structures. Good examples of this form of construction are shown in Figures 2.9 and 2.10. 2.9 Homebase, London, showing a...

Alan Ogg Royal Australian Institute Architects

1.1 Advantages of steel construction 2 1.2 Opportunity for architectural expression 2 1.5 Steel 'kit of parts' 8 2 Introduction to expressed structural form 17 2.1 Expression of bracing 19 2.2 Arched and curved structures 20 2.5 Structure envelope relationship 25 3.1 The frame as the basic unit of construction 27 3.3 Braced versus rigid frames 29 3.4 Portal-frame structures 31 3.5 Expressing the connections 34 3.6 Alternative forms of bracing 35 4 Types of beams, columns and trusses 39 4.5...

CUBIC space frame

The CUBIC space frame is a modular system in which an orthogonal grid is formed from Vierendeel girders in both directions, and joints are introduced in the top and bottom chords midway between each chord intersection. The grid can be constructed of modules 'X', 'T' or 'L' shaped in plan. These are the basic modules of the CUBIC space frame system which uses both tubular and open sections. In 1988, the roof of a maintenance hangar for Boeing 747 aircraft at Stansted Airport was constructed from...

Design Of Connection Of Diagrid Of Hollow Square Section

Diagrid Connection Details

6.2 Some examples of bolted connections to tubular members welded plate with a projecting fin, often in the form of a T-section, which permits a conventional spliced bolted connection to be made welded fin that is welded to, or cut into the section, permitting a conventional spliced connection to be made through bolts or pins with internal ferrules to avoid local crushing of the walls of the hollow section flattened ends (of a CHS), permitting a spliced connection to be welding to intermediary...

Advice For Designers In Steel P162

SCI refers to the Steel Construction Institute. Curtain Wall Connections to Steel Frames Connections Between Steel and Other Materials SCI Publication P102 Electric Lift Installations in Steel for Buildings Brown D.G. The Construction (Design and Management) Regulations 1994 Advice for Designers in Steel Joints in Simple Construction The Steel Construction Institute British Constructional Steelwork Association SCI Publication P212 Joints in Steel Construction Moment Connections The Steel...

Braced versus rigid frames

Types Braced Frame Steel Construction

The fundamental structural requirement governing the design of connections in building frames is related to the strength and stiffness 3.6 Various forms of steel connections (a) examples of effectively 'rigid' connections and (b) examples of effectively 'pinned' connections of the connections between the members, or of members to the foundations. The connections may be one of three configurations defining these degrees of strength (or more correctly 'resistance') and stiffness 1. Rigid (also...

Perforated sections

Castellated Beam Architecture

Castellated or cellular beams are examples of longer span members which have large openings within their depth. These beams achieve the benefits of greater structural efficiency by increasing the section depth for a given use of steel, and provide multiple routes for services. Cellular beams have architectural appeal by their apparent lightness and distinctive appearance in long-span roofs and floors, as in Figure 4.2. In a castellated beam, the web of a rolled section is cut along the length...

Castings for tubular members

Von Gerkan Marg And Partners Stuttgart

Castings are particularly suitable for connections between tubular members because 11.10 Tubular connections of 'trunk' to 'branch' at Stuttgart Airport (architect Von Gerkan Marg & Partners) 11.10 Tubular connections of 'trunk' to 'branch' at Stuttgart Airport (architect Von Gerkan Marg & Partners) the cost of profiling and welding complex tubular connections can be very high there are often a large number of connections of the same external dimensions in a large project complex hangar...

Space decks

Isolation Greenhouse

This system originally developed in Australia consists of pyramidal units constructed from a square frame of steel angles connected by circular steel tube bracing members to a cast steel boss. All elements of the pyramids are welded together in a jig to ensure dimensional accuracy. The boss at the base of the pyramids has two threaded holes in one horizontal direction and two threaded studs in the other to receive connecting steel tie-bars. Assembly is achieved by bolting the angle frames of...

Introduction to expressed structural form

Structural Geometry Architecture

The visual expression of a structure requires an understanding of structural function, and an appreciation of the alternative forms of structure that can perform this function. Broadly, the various forms of steel structure that may be encountered may be grouped as follows Braced frames, in which the beams and columns are designed to resist vertical loads only. Horizontal loads are resisted by bracing in the walls or cores. The connections are designed as pinned or 'simple'. Rigid or 'sway'...

Structureenvelope relationship

Inmos Factory Wales

Steel is often used in applications in which the relationship with the building envelope is important to the visual effect. There are five basic relationships between the enclosure of a building and the primary structure structure located entirely inside the building envelope (Colour Plate 1) structure located in the plane of the building envelope (Colour Plate 12) internal structure continued outside the building envelope (Figures 1.1, 1.11 and Colour Plate 13) semi-independent external...

Tension structures using tubular members

Structure Tubulaires

Tubular members are well adapted for use as the supporting or supported members in tension structures because they possess good compressive resistance as masts, etc. they are more slender than other sections for the same load resistance the end details can be designed for cable attachments or saddles pinned or articulated end-details can be made, e.g. attachments to the foundations in some cases, the tubular members may also act as the tensile elements (particularly where load reversal may...

Arched and curved structures

Richard Rogers Canopy

Arches are convex structures that are designed primarily to resist compression, as a result of their shape and the form of loading acting on them. Arches are theoretically of parabolic form when subject to uniform loading, but they can be circular, or even made from multiple linear elements. Arches also resist bending moments which are also induced due to non-uniform loading, or the deviation of the arch from the idealised shape in which the lines of thrust (compression) are located within the...

Architects working details

Architect's Working Details 1 Edited by David Jenkins and Louis Dezart Architect's Working Details 2 Edited by Alastair Blyton Architect's Working Details 3 Edited by Susan Dawson Architect's Working Details 4 Edited by Susan Dawson Architect's Working Details 5 Edited by Susan Dawson Architect's Working Details 6 Edited by Susan Dawson Architect's Working Details 7 Edited by Susan Dawson Relevant case studies dealing with steel projects or useful details from these seven volumes are presented...

Curved tubular members

Steel Roof Truss Element

Curved roofs may be formed using single-curved tubular members, double-layer members connected periodically, or tubular trusses, as illustrated in the following examples. Table 4.2 Minimum bending radii for common steel sections Joists and Universal Beams x-x axis Channels x-x axis 127 x 64 x 14 kg m 203 x 89 x 29 kg m 254 x 89 x 35 kg m 305 x 102 x 46 kg m All sections up to 432 x 102 x 65 kg m Joists, beams and columns y-y axis All sections up to 1016 x 455 x 488 kg m Castellated and cellular...

Slimflor and Slimdek construction

Slimflor Beams

A slim floor beam is a special case of a modified section where a flat steel-plate is welded to a standard UC section. This generic system is trademarked as 'Slimflor by Corus. The plate supports the floor slab so that the beam is partially encased within the floor depth, resulting in a structural system with no downstand beams, leading to reduced floor to floor heights. Two variations of Slimflor construction exist precast concrete slabs spanning between the beams13 with or without a concrete...

Stub girders

Stub girders were developed in North America, particularly to meet the needs of deep plan offices with highly serviced space, square grids, and a column spacing of 12 to 15 m. Stub girders comprise a steel bottom chord normally a UC section with short steel-sections stubs connecting it to the concrete slab. The secondary beams pass over the bottom chord. The openings for services are created adjacent Notes 485 deep openings 686x254x170 UB 450 deep openings 686x254x152 UB a Beam with rectangular...