Alaskan Way Viaduct Electrical Line Relocation – S. Massachusetts Street to Railroad Way, WSDOT & City of Seattle
CivilTech designed temporary shoring systems utilizing steel sheet piles and road steel plates with internal struts to facilitate construction of distribution line and transmission line trenches and vaults. Other tasks included designing security wall shoring and underpinning, substation shoring, and an elevated steel-frame splice tray to be mounted to the viaduct soffit to support splicing of the electrical cables. Project challenges included a high water table, poor soil conditions, adjacent buildings, and working inside an energized substation. CivilTech also performed pre-construction survey of three buildings along Atlantic Street and 1st Avenue South that were adjacent to the microtunneling activities. Buildings ranged in size from 5,400 SF to 131,000 SF. Visual inspections included documenting, measuring, mapping, and photographing existing cracks and installing gauges on representative cracks to monitor potential crack growth that might result from adjacent project activity. Inspection reports were prepared for each building to document its condition prior to contractor induced vibrations.