Few professional fields have benefited from computer technology as much as architecture and engineering. Computer aided design revolutionised the creation of complex structures, and Building Information Modeling (BIM) is going even further. 4D building information modeling results from adding the element of time to project modeling to more accurately forecast all elements of construction.
The ability to create iterations of virtual models enables extremely detailed forecasts of how a project design will work, how long it will take to build, and how much it will cost.
Sydney’s stunning new Barangaroo Reserve project, for example, was a daunting challenge made possible partly through use of BIM. The reconstruction of the six-hectare site was years in the planning stages, with several ambitious features, such as the underground cultural space and the 1.4-kilometre foreshore, constructed from thousands of giant blocks quarried on site.
According to John Hainsworth, digital leader with Aurecon, who worked on the Barangaroo Reserve project, BIM and 4D technology can result in cost savings, reduced waste, and detailed scenario plotting with multiple iterations.
“The computer can’t give you the right scenario, but they can give you many that are right, and then you choose the best scenario," he said.
Keith Marr, customer success manager for software firm Autodesk, makers of the popular Revit program, calls BIM a “proper dress rehearsal” for a project.
“BIM is a way to anticipate the future,” he said, noting that BIM is normally used for more typical structures. “Barangaroo is a unique application of the technology. It’s not a building, but still getting massive benefits.”
With BIM, the design team creates a database for the project, then begins modeling the project in 3D. According to Marr, a great advantage of BIM is cost savings.
“It’s expensive to do things in reality, and cheap to do virtually. You can do a design digitally first and get it right,” he said. “You can do iterations of various options that would never have been possible before because of the power of cloud processing. Something that might take four to five weeks to prepare a better option for a design, now we can do 2,000 options in a fraction of the time.”
After evaluating iterations, Hainsworth said, “once you have a 3D design and you’re comfortable with the look and the feel of the spatial planning of the development the contractor can use the design components to virtually build” the project.
With models built in 3D, Hainsworth said, “the construction team can use the data to sequence and plan the work in an efficient manner, optimise the materials and delivery cycles, and that is 4D.”
Adding the 4D element requires specific expertise, he said, and is “pretty useless in the hands of inexperienced people. But you give it to somebody who knows construction and knows the feasibility and the costs and the expertise of the labor and the resources, and you can really see the magic in a simulated environment.”
At Barangaroo Reserve, Autodesk’s Revit was used extensively for building information modeling on the 1.4-kilometre foreshore.
“The stones that were being placed on the foreshore were very, very large, cumbersome pieces of stone that were all unique, and we needed to reduce handling of those pieces, because they were so big and heavy,” Hainsworth said.
The engineers modeled the project in detail, with each unique stone numbered, measured, and graded for quality.
“The quarrymaster applies the grade, the digital engineer applies the location and the number,” Hainsworth said. “We created drawings that then would allow the construction team to locate the stone anywhere on the site” with extreme precision.
Creating the project virtually first also lessened construction time, Hainsworth noted, and was considerably faster than would be possible using traditional means.
“The end product, because of the 3D visualisation, the overall outcome was pretty predictable,” Hainsworth said.
According to Marr, other benefits are less obvious.
“For example the level of engagement you get from the community and the stakeholders in the design process," he said. "You get an end product that is much more in tune with the needs of those stakeholders.”