A High Speed 2 (HS2) joint venture claims it has saved more than £2M by using a new BIM-integrated tool on its package of main civils works.
SCS (a JV between Skanska, Costain and Strabag) claims it has been able to save time and cut staff numbers by using its 5D Plus, BIM-integrated approach on its HS2 design contracts.
The JV is in the early contractor involvement phase and is working to produce a design and cost estimate to build the Euston Tunnels and Approaches and Northold Tunnels sections of line.
The first-of-its kind approach, named 5D Plus, combines a cost estimating programme with a carbon estimating tool. SCS head of BIM Peter Ruff explained that by inserting the BIM model into the estimating software, the quantities from the model could be measured and combined with less tangible outcomes such as formwork, labour rates, production, materials and plant.
Consequently, SCS claims it has been able to reduce the number of quantity surveyors needed to put together cost estimates from 12 to just two, by using the new tool. This combined with the time saving from being able to assess the designs more quickly has already saved around £2M, according to Ruff.
Speaking to New Civil Engineer, Ruff said the tool is being used to give a level of transparency and traceability which had not previously been possible on a project of such scale. Use of the tool saw SCS win the Rail and Transit category at Bentley Systems’ Year in Infrastructure 2018 Awards, recognising those doing most to advance digital technologies.
“This is what it is, it’s very transparent and auditable which HS2 loves,” he said. “They asked us for our drawings and we said we didn’t use them, we’ll just give you access to the estimating system, so it’s all there for you to validate the quantities.”
A library containing the embodied carbon contents of the different elements is also incorporated into the software to rapidly assess the design’s carbon impact. Ruff said incorporating the carbon element of the tool was a very important step in its development.
“We also used it at tender and once you start using it, you see the effect changing the different components has,” he said. “For example, D-walls [diaphragm] have a lot of carbon, so we’ve taken them out. To have that visibility, rapid assessment ability and transparency is amazing.
“It’s important as we’ve been asked to save 15% carbon from the baseline so we had to find a way of doing it.”
In June, New Civil Engineer revealed that initial costs for HS2 main civil works were coming in around £1bn over budget. As a result the notice to procede - which allows the start of construction - was pushed back eight months.
Ruff said building the programme had taken an “almost obsessive” attitude to keeping costs down while improving efficiencies.
“We broke the whole thing down and asked: Why do we want to do things? What do we actually want it to do with it? and then built it around that,” he said.
“We treated it very, very seriously, almost obsessively seriously and for that you need to have an ultra detailed approach which I don’t think other companies have done before. They might gloss over bits and follow these standards and say it’ll be ok, but that’s not been our approach.”
The new programme has been welcomed by HS2, with the idea being shared to the other joint ventures working along the line.
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