NZ SEISMIC INVENTION IS “GAME CHANGER” IN GLOBAL CONSTRUCTION
New Zealand is on the verge of becoming a world leader in low-cost and low-damage seismic engineering, says the winner of the 2022 Ivan Skinner Award, Dr Shahab Ramhormozian.
Over the past years, Ramhormozian has significantly improved and finetuned the revolutionary sliding hinge joint technology that was initially developed by his New Zealand research mentors, and the EQC-funded award will assist in demonstrating that the innovation can be used across a wide range of building types.
“This technology was developed many years ago, but we are at a critical stage now to be able to finish the work, so we need to do more so it can be eventually adopted into building codes,” says the engineer who has just received the award at the annual conference of the New Zealand Society of Earthquake Engineering (NZSEE).
The senior lecturer at Auckland University of Technology (AUT) continued the ground-breaking work by Dr Charles Clifton (who conceived the initial idea in his PhD) at the University of Auckland and Dr Gregory MacRae at the University of Canterbury, who had developed the sliding hinge joint technology.
Their innovative work was in direct response to the Northridge and Kobe earthquakes in the mid-1990s in which buildings suffered much more damage than expected.
“Up until then, buildings were designed to save lives, but not able to deal with stronger earthquakes, which had a huge economic impact, like we also saw in Christchurch,” says the Iranian-born engineer, who moved to New Zealand over a decade ago.
“Traditional designs were simply not working if the earthquake demand on building was higher than expected, so Charles Clifton started work on a low-damage sliding hinge joint system, which dissipates the seismic energy and is also able to be partially replaced or repaired like an electrical fuse when an earthquake exceeds the maximum load it was designed for.”
Engineers and academics around the world have been quick to adopt and replicate the technology.
Ramhormozian says the original friction sliding hinge system was ground-breaking, but had some shortcomings such as design and construction accuracy and precision issues as well as post-earthquake loss of strength.
The AUT lecturer addressed these shortcomings in his breakthrough PhD research when he developed the ‘Optimised Sliding Hinge Joint’, which is currently used by BECA engineers in three Hamilton CBD buildings under construction by Hawkins for Tainui Holdings Group.
“We discovered ways to install different components and tighten the bolts in a world-first manner, which resulted in a highly accurate system without the necessity to repair the joints after an earthquake,” says the researcher who even called on one of Nasa’s partners to source the most resilient key components on the planet.
The Auckland researchers have been working closely with their peers in Italy and China where the technology has been adopted and tested, “so we all share and use that data to confirm our findings and make further improvements”.
The New Zealand innovation has prompted eight leading universities across Europe to launch a joint project, which has received a multi-billion Euro grant from the European Union and will soon start construction on the first building in Europe, using the new technology at the University of Salerno in Italy.
EQC chief resilience and research officer Dr Jo Horrocks says that the optimised sliding hinge technology is a terrific example how EQC’s research funding directly impacts on people’s lives and properties.
“EQC invests around $20 million each year in natural hazard research funding, so it is wonderful to see how a relatively small investment by the New Zealand taxpayers can save us, and other countries, millions of dollars in future earthquake damage,” Horrocks says.
NZSEE president Helen Ferner says that Ramhormozian was a worthy recipient of the prestigious Ivan Skinner Award and that his work will have global implications.
“The award enables Shahab to continue the amazing work done by him and other brilliant New Zealand minds from academia and industry with whom he collaborates and will help engineers around the world.”