DIGITAL TWIN TECH ALIGNS WITH OFFSITE EFFICIENCIES

The Sixty Martin Place project participants comprise a “who’s who” of cutting edge thinking: Melbourne-based immersive technology studio Phoria, digital twin specialist Willow, and Australian commercial office developer Investa. Experts in 3D scanning and spatial data management, Land Surveys, both scanned and surveyed Sixty Martin Place during construction, before working with Phoria to generate a 99% accurate 3D model of the physical building. Lendlease had been awarded the contract in early 2016 following a competitive tender process The contract form was a lumpsum D&C contract, with Lendlease responsible for building delivery by Q3 2019.

The project entailed Investa and Willow’s development of what’s been described as Australia’s first digital twin for operations at Sixty Martin Place, with Lendlease. Upon building completion, Willow integrated 71,848 digital assets and other data sources with its WillowTwin software platform, to create a smart and tech-empowered built environment. Phoria’s collaboration with Investa and Willow resulted in the development of an AR application that could align digital twin data with the real-world environment and enhance the user experience available at Sixty Martin Place.

The whole initiative also resulted in efficiencies in the building process with key relevance for the offsite elements.

Shen Chiu, National Development Director of Investa told Built Offsite that Investa embarked on a full end-to-end digital twin process for the scheme from early project inception.

“The operational value of an accurate 3D model and digital building asset register was apparent from past experience with developments at 40 Mount Street, North Sydney and again at 567 Collins Street, Melbourne. However, in both these instances, the digital requirement was specified only as part of the construction process, resulting in inefficiencies and missed opportunities afforded by a more integrated Building Information Modelling (BIM) process.”

“The industry has been practising digital documentation for over a decade, with various successes in certain disciplines and sectors. The design sector, in particular, has been fairly progressive in its digital documentation and coordination processes, and the construction sector has similarly found value through digital planning and offsite fabrication utilising digitally co-ordinated design, manifesting with onsite time savings, safety improvements and waste reduction. However, collectively the use of digital documentation leading to a digital twin has thus far been fragmented without the guiding hand of an overarching client-led and outcome-driven requirement.”

Investa mandated a digital twin deliverable in all of its project brief requirements, spanning design, procurement, construction delivery as well as tenant fit-out. This required Investa to provide detailed documentation of the standards and protocols to be applied to all of the project phases and resulting in digital documents. The designers and contractors then signed up to a fully digital delivery and as-built and operational digital twin deliverable.

There were two specific areas where Lendlease identified clear benefits to utilise the coordinated 3D model and allow offsite fabrication to take place, Chiu confirmed. In short, the accurate digital twin process allowed Lendlease access to a level of resolution of in-ceiling services, that it was able to confidently pre-fabricate a 12 m module of mechanical, hydraulic and electrical services and install the total in-ceiling services for a 1,500sqm floor plate within a drastically reduced time frame. Other items like vertical risers and the ducts inside them, were also prefabricated in modules for safety and speed of installation.

“The normal process for in-ceiling service installation is a time consuming and resource-intensive process,” says Chiu. “Once the structural formwork is removed and the floor cleared, the process of lifting, storing and then installing in-ceiling services usually takes place elementally. Larger ducts are installed with overhead hanger rod fixings, then smaller pipework, electrical cable trays and then finally ceiling grids and the ceiling tiles.”
“Lendlease was able to prefabricate a 12m x 1m module of everything except the ceiling grid, to simplify the process. A structural frame was fabricated, housing the elements, and this was then transported to the site, lifted in one piece to the floor and installed by two operators using a scissor lift on site. The whole modulated process reduced the onsite time to install the in-ceiling works from three weeks to three days.

It also reduced the amount of handling of smaller elements, onsite wastage through incorrect positioning and onsite cutting, and safety issues of multiple trades working adjacent (or on top of) each other. The integrated modules also reduced site storage and allowed a larger number of facade panels to be stored, reducing double handling of facade elements when delivered to site and overall cranage coordination time. From a client’s perspective, notwithstanding the savings in onsite works, the laying out and better organisation of the works was noticeable during services installation of each floor.”

“Lendlease was able to prefabricate a 12m x 1m module of everything except the ceiling grid, to simplify the process. A structural frame was fabricated, housing the elements, and this was then transported to the site, lifted in one piece to the floor and installed by two operators using a scissor lift on site. The whole modulated process reduced the onsite time to install the in-ceiling works from three weeks to three days.” Shen Chiu, National Development Director, Investa.

The second element that utilised offsite prefabrication was the vertical ductwork. The Work Health Safety aspects of working in a confined space with the risk of falling from heights are well recognised by the industry. Lendlease had already trialled alternative installation methods at its previous development at Barangaroo, and the fully-coordinated BIM at Sixty Martin Place afforded it an opportunity to further de-risk the installation process by prefabricating 3-floor lengths of ductwork and installing them in a safer manner, with a digitally co-ordinated structure and positional accuracy of the required horizontal connections.”

“Investa is committed to doing things better, safer and more sustainably,” says Chiu. “Through its journey of ‘innovation through action’ at Sixty Martin Place, the industry now has a clearly defined and disciplined example of utilising an integrated digital twin process to add value to all stakeholders and improve the current delivery process for everyone involved.”■