SEATTLE, Wash. — New and expanding cracks on the shaky Alaskan Way Viaduct will likely be fixed with epoxy.
Experts said it is a common, and largely effective, fix that has some limitations.
Spokesman Travis Phelps of the Washington State Department of Transportation said the epoxy for fixing bridge cracks is more fluid than what you might use on a crack in your basement.
"This is a lot different type of epoxy. It's industrial grade concrete-sealing epoxy," Phelps said.
After crews apply a paste epoxy on the surface, they use an injection gun to shoot liquid epoxy into plastic ports in the crack - which ensures the entire crack is sealed.
"It's almost like you're injecting garlic into a chicken," Phelps said.
Phelps says using epoxy on the newly-discovered viaduct cracks will cost in the thousands of dollars, which is pretty cheap in the world of road maintenance.
State bridge engineer Tom Baker said epoxy is also effective.
"That seals the crack, joins the two sides of concrete back together and provides at least all the strength of the original concrete," Baker said.
Retired bridge engineer Stewart Gloyd told KIRO 7 epoxy has been used successfully for decades.
But he said it must be applied correctly, and it won't necessarily keep more cracks from forming.
"Depending on what caused the cracks to begin with, the cracks may re-occur nearby," Gloyd said.
State engineers said Tuesday it's too early to tell if any work will need to be done to the foundation of the viaduct.
They plan a more detailed inspection of the new cracks during an all-day closure of the viaduct on Saturday, March 22.
State officials believe the cracks discovered near Seneca Street during a March 1st inspection were caused by residual effects of the 2001 Nisqually earthquake, not by tunneling a half mile away.
KIRO
