Controlled Demolition Inc. (CDI), Phoenix, Maryland, performed the preparation for and explosives felling of a 19-story, reinforced concrete office building in Evansville, Indiana, Nov. 21.
The office building, located on 420 Main St., served as the headquarters to Old National Bank from 1970 to 2004. After the bank moved to a new location downtown, the 166,300 square foot tower’s occupancy dropped, and its condition began to deteriorate.
Following multiple failed efforts to rehabilitate the building, the city of Evansville announced a new redevelopment project at the site. To facilitate this project, 420 Main was slated for implosion after being deemed in too poor of condition to save.
CDI acted as the explosives subcontractor to main demolition contractor, Indianapolis-based Renascent Inc. Renascent, working for general contractor Barton Malow, who represented the developer, DOMO Development Co. LLC, performed environmental remediation in the structure before soft stripping the building and gutting out CDI’s specified shot floors.
Renascent placed debris to support the two street side basement walls which had not been designed as free-standing retaining walls. They also installed cables on multiple floors of the structure, per CDI’s design, so that CDI could pull the tower away from those basement walls to remain and adjacent streets/structures.
Vibration monitoring of CDI’s felling of the 18,000-ton structure demonstrated vibration levels well below regulatory guidelines.
Watch a video of the implosion below, courtesy of CDI: