Cementation, the foundations division of Swedish construction group Skanska, says that its MLT60 maintained load test test system is capable of testing loads up to 60 meganewtons (MN), making it the UK’s highest capacity system for pile testing.
It has been developed entirely in-house and is designed to assembled and disassembled for transport between sites.
Cementation has just completed testing the equipment on the HS2 Euston site with main contractor Mace Dragados Joint Venture (MDJV) where was fitted with a 40 MN test beam giving it the capacity to test loads up to 40MN.
While this is not the full capacity of the new system, which when fitted with a larger test beam can go up to 60MN (equivalent to 6,000 tonnes), it still raises the bar for geotechnical testing as previously only loads of around 30MN could be achieved with standard load testing arrangements, Skanska said. On the Euston site, piles have been tested to load of up to 33.5MN.
Skanska said that having the ability to accurately test foundations to much higher loads and knowing when they will fail offers efficiency gains as scope and designs can be refined and excessive over-engineering eliminated.
The MLT60 has data capture and instrumentation built in using fibre optic sensing technology. This enables the capture and analysis of data on where forces are going, how the ground is behaving and other factors that may influence the point of failure.
Three years in the making, designing the equipment involved digital visualisation and modelling, involving site teams, scenario testing, 3D printed scale models and digital rehearsals of the construction.
Cementation Skanska operations director Andrew Entwistle said: “The MLT60 is a step change in pile testing capability for the industry. Its ability to accurately test foundations at such high loads all the way to failure means we can validate the effectiveness and improve the efficiency of designs – reducing both cost and carbon.
“As piles have got bigger and deeper, testing to failure on major infrastructure and large scale commercial and residential high-rise projects has got harder. So, designs have been based on assumptions with additional safety margins added in. The new MLT60 is a game changer in this regard because it enables us to rationalise designs.
“We are all incredibly proud of how all of our teams came together to create such a unique and forward-looking piece of equipment.”