DOT crews ready Front Street overpass for seismic work
June 19, 2009
By Warren Kagarise
NEW — 2:08 p.m. June 19, 2009
Crews working beneath the Interstate 90 overpass at Front Street are taking the first step toward strengthening the roadway to withstand earthquakes.
State Department of Transportation crews are preparing the overpass for new components. DOT spokeswoman Broch Bender said the first stage of the project is “similar to taking measurements to fit a suit.” She said the traffic impact would be minimal when the project begins in earnest this summer.
DOT crews will bring 16 bridges up to present-day earthquake standards between Richards Road in Bellevue and Winery Road near Snoqualmie. Engineers estimate the $9.4 million project will be complete by October.
Crews will strengthen columns to prevent girders from slipping off the bridge piers during an earthquake. Bender the bridges will be able to withstand greater seismic stress after the retrofit is complete.
Columns will be swaddled in column jackets to prevent the bridge column from crumbling apart during an earthquake. Crews will also add girder stops to prevent bridge girders from sliding or tipping.
Bender said girder stops would prevent the overpass from swaying side to side in an earthquake.