Advance Steel Helps Launch RN Submarine Museum Wing
1 Aug 2006
Advance Steel helped structural steelwork company Hawk Structures create an iconic new wing for the Royal NavySubmarine Museum in Hampshire.
CADs 3D modelling software, Advance Steel has been used on a project which provided a unique set of challenges, and once the architect and engineer's design was viewed it was up to Hawk Structures to ensure the steel structure delivered on all fronts. The project was a high profile one, forming part of a £3.1M major expansion of the museum, which included a Heritage Lottery Fund award of nearly £2M.
The Royal Navy Submarine Museum preserves and promotes the history of this important part of the fleet and is based in Gosport, Hampshire, opposite another iconic structure - The Spinnaker Tower. The new John Fieldhouse Building was formally opened by HRH The Princess Royal in 2005, and the museum featured in a BBC series 'Take One Museum'.
The new building is named after the late Admiral of the Fleet, Lord John Fieldhouse of Gosport - the most senior submariner in history. It was designed to house the historic X-craft minisubmarine HMS X24 as well as accommodating information areas, a reception, lecture/corporate entertainment area and a 'Submarine and Sciences' gallery. HMS X24 is similar to the ones that crippled and effectively put out of action the Tirpitz during World War II, and now takes pride of place, having been set in its steel cradle before the rest of the structure was erected around it.
Modelling the Structure The first challenge in detailing the structural steelwork for the museum was the shape, which was designed to mimic the shape of a submarine, including a conning tower. John Bennett, Advance Steel CAD Manager of Hawk Structures was tasked with detailing the steelwork, and brought his experience from working on similar structures using 3D models, as well as his Advance Steel expertise to bear on the project.
From the engineer's conceptual drawings, the first task was to develop a model of the main structure in Advance Steel. This would help anticipate any problems and prove the concept.With a curved structure such as this the outer skin steelwork must be bent in two directions, so to achieve the correct shape John twisted and rotated each of the 20 building ribs at its own angle. The model was numbered for drawing production, with any changes to it also automatically updating the drawings themselves.When John required help he was able to contact CADS Advance Steel product experts who provided tips on working with curve generation amongst other items. Three separate plates were made for the main beams, to allow for either in-house, or as eventually chosen, Fabsec beams. However, the curved beams were eventually supplied by Barnshaw.
Interior Design The interior specification added some very specific requirements, including creating the impression of a submarine interior. Using curved cellular style beams the architect and engineer had created the ribs and tubular look associated with a submarine. Whilst using cellular beams were not innovative in themselves, the fact they needed to be a decorative feature and bent to a steep curve required a new approach. Therefore, rather than use an existing cellular beam, heavier standard universal beams were rolled and formed, with holes profiled and cut by Barnshaw to mimic a cellular beam.
Firstly the apertures were spaced for the best aesthetic effect, ensuring that when constructed the holes looked uniform, regardless of the impact of other structural connections and interior items. These adapted universal beams then needed to be bent beyond the known tolerances of existing cellular beams, without any distortion or kinking of the apertures. A new Barnshaw machine helped achieve this. This use of cellular beams was highly unusual, as no structural advantage over a standard universal beam was gained. Any gains were purely cosmetic.
The secondary structure (outer skin) presented more challenges, driven by the client's exacting requirements. This consisted of a base of marine ply nailed to the steel framework, then foam insulation with metal cladding on the outside. A glass wall also runs around approximately two thirds of the side of the building. Special details at the end of beams and weld details were all incorporated in the final solution, with items such as individual stainless steel pins drawn in to the model. The outer skin had approximately 800 pieces that had to be put in by hand.
Hawk Structures Incorporated in January 1994 Hawk Structures has developed into a mature structural steelwork company, with design & build capabilities. The firm has used CADS for many years, following its principal's former Senior Management roles at Conder Steel of Winchester. Hawk now operates several software licences, for CADS A3D MAX, SMART Portal and SMART Engineer - 'Calc-Pad' type software and CADS Steelwork Member Connections.
Hawk Structures Technical Director, John Salter said:
'Choosing and training our draftsmen for Advance Steel was all the easier because of previous AutoCAD experience and/or attendance at a local training college combined with using AutoCAD on the job.'
Hawk's detailers have received AutoCAD and Advance Steel training from CADS, both on site and at CADS Broadstone headquarters. 'Training is essential', said John Salter, 'without it we simply would not have made the progress necessary to achieve a return on our investment. After each CADS course our detailers returned to their work with more knowledge and expertise and renewed enthusiasm.' Hawk bought AutoCAD and Advance Steel in March 2000, before which material lists were all manually written.
The Royal Navy submarine Museum project highlighted a number of important advantages in using Advance Steel for the firm. One was the ease with which information can be extracted from the model and imported into an Excel document to aid project management. Mr Salter said: 'Many third party drawings simply lack the accuracy required for fabrication and erection. Because it's our job to make sure the structure fits together on site, we often choose to start our Advance Steel models and drawings from scratch.'
CADS continues to provide expert help via its support team to Advance Steel users such as Hawk Structures. This includes recent help for Hawk to bring its manual material list system together with its models, enabling a material list to be rapidly created. Hawk Structures has made the most of the experience gained. It now operates four Advance Steel licences and is able to tender for sophisticated projects that go well beyond the average portal frame.
Further information: Hawk Structures Ltd Lode Hill, Downton Nr Salisbury, Wilts. SP5 3PP
