Reaching higher ground

Prof. Tim Ibell takes a look at The Jump Factory, and celebrates the amazing innovation that is behind the concept


Prof. Tim Ibell takes a look at The Jump Factory, and celebrates the amazing innovation that is behind the concept

The 2018 Structural Awards shortlist was announced in July 2018, showcasing some of the world’s best examples in engineering from large corporations and small practices alike. It’s an annual highlight in the Institution of Structural Engineers’ calendar and is the perfect way to celebrate the extraordinary talent and skill of the Institution’s membership and the wider industry.

I have been involved in judging the awards for five years and it’s a great privilege to be asked to chair this year’s panel. One category which always captures my imagination is ‘Construction Innovation’. This year the category has offered a fascinating collection of projects demonstrating both engineering ingenuity and creativity.

One entry which particularly interested us this year was Mace’s ‘The Jump Factory’. A ten-storey demountable enclosure, the project creates a factory environment in which a high-rise building can be constructed.

Earlier this year, the efficacy of this extraordinary innovation was demonstrated through two residential towers of 26 and 30 storeys which were completed in Stratford using this pioneering construction technique.

Complex brief
Support for the Factory is integrated into the design of the main building. Bespoke jacking frames are incorporated into the Factory structure, allowing it to be raised up incrementally as each level is completed.

It provides four internal working levels at which frame construction, load-out of internal fixtures and fittings, and façade installation is finalised. This allows the completion of one floor per week.

The entry fascinated the panel and I was keen to find out a bit more, so I caught-up with Des Mairs a director at Davies Maguire, the structural engineers behind The Jump Factory, to get his take on this significant development in the construction industry.

Inspiration for the system came to Mace from abroad, as Des highlights: “They had seen a high rise project being built in Holland using an enclosed ‘factory’ and felt the approach would provide an efficient way of constructing the twin N08 towers at the East Village site in Stratford.

“Particularly,” he continues, “Mace was keen on advancing the concepts of pre-cast and modular construction and wanted to explore the programme benefits of carrying out this form of construction within an enclosed space.

“That’s when we became involved. Mace was clear on their spatial requirements within the brief, loading bay at one end, storage and welfare at the other. This needed to be complemented by access walkways around the full perimeter. One of the key operational requirements was uninterrupted crane access across the complete internal footprint of the site. Finally, the factory needed to be supported on four corner columns to ensure structural stability.”

Des observes that it was a basic brief, but enough to develop the requirements: “As the project progressed, trussed portal frames in both directions became necessary to ensure the stability of the factory, all without inhibiting the gantry crane movements.

Game-changer
“Inspiration for the final design,” he says, “developed directly out of the brief. To keep the self-weight of the factory to a minimum no structure was provided that wasn’t necessary. The size of the four corner columns had been fixed, architecturally and could not be changed, so our work was framed by this criterion. However, there had to be an element of material flexibility to the original blueprints. For example, the concrete columns specified in the original design could not carry the heavy loads, so these had to be changed to steel.”

The Davies Maguire team had envisaged early challenges arising from the supporting columns but it was not until the construction journey had started that they presented themselves.

“The structural form crystallised quickly, but the support and lifting methodology took time to refine. We constantly needed to develop solutions which would support the whole structure but also ensure that the whole frame could be easily lifted from one level to another as the jumps progressed.

“The main difficulty we faced,” Des highlights, “was getting the supporting corner columns to work whilst maintaining their overall size. To get the columns to work, we had to use slender bearing plates to minimise eccentricities. The entire factory weighed 500 tonnes and needed to sit on four bearing plates 450mm long by 50mm wide. This pushed the material to its limits, as much a challenge as it was a highlight when it all came together!”

And what of its applications? “The Jump Factory has huge advantages,” he enthuses. “Precast concrete walls, columns and slabs, bathroom pods and pre-formed M&E cassettes have all be done before but this structure provides truly ‘factorylike’ conditions to optimise installation.”

Des concludes, as one might expect, on a high: “It’s a game changer and comes into its own when combined with a strong supply chain. In the case of the Stratford project, Mace was so efficient it was able to successfully plan for one floor completed per week. The Jump Factory was essential to this ambition, which was achieved very quickly once it was up and running, ensuring both consistency and rapid construction all the way up to the 30th floor.”

Indeed, this new building system has huge potential for the built environment. The judging panel and I are of the opinion that The Jump Factory is a step change for high-rise builds as it accelerates higher-quality construction in a safer environment. As such it is impressive enough to achieve a coveted place on this year’s shortlist, alongside the other worthy projects nominated for the ‘Construction Innovation’ category.

Prof. Tim Ibell is Chair of the Judges for the 2018 Structural Awards. The Structural Awards are the world’s foremost celebration of structural engineers as innovative, creative design professionals and the guardians of public safety. For over 50 years, the Structural Awards have showcased the world’s most cutting edge engineering achievements. The Institution of Structural Engineers is the world’s largest membership organisation dedicated to the art and science of structural engineering. The Institution has over 28,000 members working in 105 countries around the world. The Institution is an internationally recognised source of expertise and information concerning all issues that involve structural engineering and public safety within the built environment.

For more information, please see www.istructe.org/structuralawards/home