Steelwork destined for Leicester Tigers’ rugby stadium
One of the many benefits of steel is its limitless possibilities for the manufacture of bespoke structural components.
Construction design, coupled with ever more creative architectural modelling and engineering software, has seen a diversification away from routine and standard components towards more uniquely designed structural elements. Items such as transfer beams, plate girders, fabricated member trusses and cellular beams are now to be seen in a host of building types.
Leeds station arches
Many of these items, although made from steel plate or sometimes from steel sections, are often outside the scope and capability of conventional steelwork contractors, or those who specialise in one type of product only.
Generally, once structural components are of a size/weight which exceeds the range of normal mill rollings then steel plate becomes the base material from which structural components are made.
In order to produce bespoke sections from plate, the producer needs the capability and capacity to deal with long plate lengths (up to 20m in some cases). All associated equipment such as offloading fork trucks, profile cutting beds, overhead craneage, shot blasting and automatic welding needs to be appropriate to the specific requirements demanded by heavy structural components.
When considering a supplier of bespoke structural components, the buyer needs to be very aware of the detail and specification level which the project demands.
It may be the case that a project calls for supply of 60t trusses comprising top and bottom boom and infill members, which are all fabricated plate girder sections.
Execution Class 3 steelwork, but calls for Execution Class 4 testing on specific joints within the components or structure.
There may be specific requirements for unique traceability or a nominated external NDT supplier.
There may be a complex sequence of assembly and a requirement for inspection at specific stages of the component build process.
There are numerous examples of bespoke steel components to be found in all construction sectors. One of the most widely used examples is the cellular beam, most often used in commercial buildings to allow the accommodation of services within the structural void, and/or achieve efficient long spans.
“In the past decade a number of very capable and strong suppliers of heavy bespoke structural components have emerged. Steelwork projects can now benefit from this new level of management skill and manufacturing capability which our industry now offers,” Jamestown’s Managing Director Fiacre Creegan. Cellular beams, which are usually I-section beams with regularly spaced holes, are generally produced by specialist companies and then further fabricated by steelwork contractors into elements for a particular project.
Cellular beams can also offer a solution for curved roof applications, combining a considerable weight saving compared with plain sections.
Car parks also make use of cellular beams as they offer a lightweight and more cost-effective section for the long spans needed in these structures, while the holes provide the otherwise dark car park with a lighter environment.
Sponsors: Structural components
Headline: Jamestown Cladding & Profiling Ltd Bronze: Kloeckner Metals UK