140,000 sq. feet Harold M. and Eugenia S. Thomas Comprehensive Care Center on TriHealth’s Bethesda North campus is a three story facility that hosts a cancer center, heart + vascular institute, and other outpatient + imaging services. Each department has its own entry off a central atrium which features design elements including an unsupported ribbon monumental stair, custom wood paneled screen walls, and exposed structural steel tapered columns. It also has a partial basement with a connector tunnel to the adjacent medical office building.
The building is a composite steel moment frame structure supported on deep foundations. Custom steel plate girders were designed to allow for large cantilevers supporting the upper floors. A high floor to floor height allowed for linear accelerators on the main floor, with shielding constructed with modular high density blocks supported on a large mat foundation.
The upper floors have multiple decks and viewing gardens; some are open and offer exposed views, while others are partially shielded by an extension of the terracotta rain screen system serving as a screen wall. Schaefer served as the engineer of record, as well as the specialty engineer for the terracotta rain screen system, custom wood-paneled architectural screen walls, the cold formed metal framing, and assisted with the design of the monumental stairs and medical equipment supports.
The two primary structural design challenges for the monumental stair were providing appropriate stiffness to control deflection and displacement due to torsion resulting from the helical shape, and potential serviceability and vibration performance. Working with the design and construction team and appropriate consultants early on, Schaefer developed a plan that met design criteria and the owner’s budget.