Macdonald Bridge deck replacement snag causes rush hour havoc
Posted Oct 19, 2015 03:02:22 PM.
Last Updated Oct 19, 2015 03:17:51 PM.
This article is more than 5 years old.
HALIFAX — The extended closure of the Macdonald Bridge caused havoc during rush hour on Monday morning.
Crews replaced an entire segment over the weekend – a process that will be repeated another 45 times before the $150 million project is complete.
Chief bridge engineer Jon Eppell says it was the removal of an existing deck took that took longer than expected which ultimately caused the delay. Once the original deck was removed, he says they then had to strengthen and modify the cable bent to make it safe for motorists.
“Those modifications were hampered by having the remove an old bearing that we could not get into beforehand inside the cable bent. That had to be cut into chunks, some as small as a phone. The access to that is so restrictive that only one person can get into it at a time,” said Eppell.
Once the deck was removed, Eppell says they then had to strengthen and modify the cable bent and then make adjustments to the vertical hangers, a process which also took longer than anticipated.
He says the raising of the new segment went well, but they had difficulty making adjustments to the new traction rods being installed at the cable bent.
While driving over the Macdonald Bridge, you will notice a change in the deck level as it dips near the Dartmouth side. Eppell says this is done for structural reasons and is completely safe for motorists to drive over.
“The reason we have the kink in the deck is because we have to balance the loads between each one of those vertical hangers to make sure nothing is over-stressed,” Eppell explained.
He says they’ll be holding a debrief session Monday in an effort to prevent further delays and to plan for the next segment set to be removed next weekend. When asked whether there will be further delays, he said there’s always a risk.
“Optimistically we will not have any more that will go over. Realistically, we’ve got contingency plans that if it happens, we will try to accelerate things and get things open on time.”
Eppell says rather than rushing to open at 5:30 a.m., crews took their time and made sure the bridge was safe before reopening to traffic.
He says they’re expecting to get the typical segment replacement down to ten hours so they can proceed with overnight work instead of just over the weekend.
