DEMM Engineering & Manufacturing
Feature – Christchurch bridge lift
In mid-December, HTC announced it was to lift a Christchurch bridge off its foundations so earthquake out how it all went...
Necessity has long been the mother of invention, and for one Kiwi firm in the specialised equipment sector, the challenge of the Christchurch rebuild has also set up an unexpected opportunity for expansion.
The 31-year-old company, HTC Specialised Tools and Equipment, has made an investment almost unequalled on either side of the Tasman, of five Durapac Syncmaster Synchronised Lifting Systems, which are together worth $1 million.
The five units not only comprise the biggest system of its kind in the South Pacific, HTC is the only company making it available for hire for construction and infrastructure projects of all sizes throughout New Zealand and Australia.
Evidence of its potential was produced in mid-December 2013, when HTC completed a unique bridge-lifting exercise in South New Brighton.
The Durapac hydraulic lifting system was deployed as part of the Scirt/Fulton Hogan Bridge Street bridge repair project to restore a critical route from the earthquake-damaged eastern Christchurch suburb to the CBD.
It was the first time a manoeuvre of its type and technological complexity had been performed in New Zealand or Australia, and the sub-24-hour operation went off without a hitch, meeting the deadline and allowing for the restoration of the following Monday morning traffic f low.
Though the bridge deck itself remained viable after the earthquakes, damage to the abutments meant only a heavily reduced traffic f low could be supported, and the bridge required re-levelling of 200mm at its lowest point. Once level, an equal displacement lift was performed to permit the necessary repairs beneath.
In a major technological advancement beyond the oldfashioned method of lifting, the hydraulic system – which spreads more than 7,200 tons of lift power across 72 separate hydraulic rams – was controlled from a single touchscreen display throughout the operation.
The powerful on-board computer was tasked with keeping each hydraulic ram within a pre-set tolerance with all of the other rams, and the system was set to actively monitor weights and subsidence at each lifting point and to pause the lift if an error was detected.
HTC’s five Durapac units were connected to create and control up to 40 lifting points. The ‘spread’ this permitted was key for a weighty project such as Bridge Street, in which more lifting points mean less stress on the structure.
With the project, which was a year in the planning by HTC and colleagues at Scirt and Fulton Hogan, the company has been fielding enquiries about the project from around the world.
HTC’s Christchurch branch manager Daniel Brice, says: “This project showcases the wider economic potential stemming from capital investment.
“Not many firms are able or willing to make a similar capital expenditure, and having done so opens up a potential new income stream across New Zealand and in Australia.
“All five units can fit easily into one shipping container, so this service to the Australian market is viable.”
Contact HTC 0800 420 000.