The Maritime Building in Seattle: DYWIDAG Micropiles ensure Stability and Seismic Safety
The 1910 Maritime Building in the harbor area of downtown Seattle, Washington in northwestern USA was originally used as a warehouse. Now, it is being comprehensively renovated and expanded by the addition of three new floors.
The existing 16,072m² (173,000ft²) 5-story structure is a timber post and beam building with a reinforced concrete exterior. The building will be transformed into a modern mixed-use building with approx. 2,323m² (25,000ft²) of additional office space and another area roughly the same size for retail facilities.
Within the remodeling and expansion scope, the building had to meet current safety regulations, which is why it is being seismically retrofitted. A critical part of enhancing earthquake stability was the reinforcement of the building’s foundation by a posterior installation of 151 DYWIDAG Micropiles at the lowest floor. Kulchin Foundation Drilling Company decided to use micropiles consisting of 57mm Ø, Grade 80 DYWIDAG Threadbar. In this system, the high quality thread ensures an easy coupling of the 8 short pile segments and a safe installation in the borehole.
In total, 151 DYWIDAG Micropiles in lengths of 22.9m (75ft) each were successfully installed in very tight conditions with less than 2.4m (8ft) of overhead clearance.