Designed by Gordon Bunshaft to resemble “a large piece of functional sculpture,” the Hirshhorn Museum has a cylindrical design that stands in sharp contrast with its traditional neighbors on the National Mall. The cylinder is a solid curved concrete exterior wall sitting atop four large cast-in-place concrete piers that have an exposed aggregate finish to match the cylinder’s precast facade. The cylinder’s elevated placement opens up the central plaza below for circulation and sculpture installations. The structured plaza slab sits over a double-height below-grade area containing gallery and back of house spaces.
Silman has worked directly for the Smithsonian Institution performing structural investigations, repairs, and renovations on the museum and gardens. Past projects include a site and material investigation for evidence of material distress and of the exposed aggregate concrete walls, which have a history of significant cracking. After evaluating available documents, Silman conducted a visual survey, planned selective probes in concert with curatorial staff, and documented conditions. Material testing revealed a lack of air entrainment in the original mix as the cause for deteriorating conditions. Silman developed measures for potential remediation and preservation schemes to reduce ongoing deterioration.