Constructed in 1960, the Behavioral Sciences Building is a concrete frame structure with glass and concrete panels infilled on the building exterior and supported on a mat foundation. The irregular wall layout and open lower levels created an unsafe structure that was at risk to collapse in a major earthquake.
Previous structural evaluations using linear analysis methods recommended seismic retrofit measures that included adding multiple new shear walls for the entire height of the 15-story research tower. The University estimated this could be completed in nine phases over a 10- to 15-year period with an estimated construction cost of around $17 million.
Instead, Reaveley recommended performing a nonlinear analysis of the structure. This innovative approach better accounts for the strength and ductility of the existing structural elements over the less rigorous linear methods. The result was a design that reduces the height of the added shear walls to just the first five stories – a savings of about $5 million in construction costs compared to the original program.
By reducing the number and height of the new shear walls, the project timeframe was reduced from nine phases to six. The building structure will also meet life-safety performance objectives for a major seismic event. The time and money savings have given the University more flexibility in the schedule, lessened the impact on the building occupants, and reduced the total upgrade cost (funds that can now be used for other campus capital improvements).
Salt Lake City, UT