By using conventional structural systems to support the restored landscaping and integrating unique and sophisticated foundation elements, Silman facilitated the placement of the new underground extension directly against the historic south portico at a depth of up to 28 feet below the existing foundations.
The Virginia State Capitol Building, designed by Thomas Jefferson around 1780, combined a classical style with modern construction techniques, setting a precedent for American public architecture.
Using best practices of preservation engineering, Silman worked with the project team to meet client needs for master planning guidance and provide renovation recommendations to minimize the impact on the historic landmark. The master plan included a comprehensive investigation of 27 buildings and the surrounding landscapes on the historic campus.
The project team subsequently completed a complex renovation and a new below-grade expansion to accommodate visitors.
Silman protected the historic structure with unique structure and foundation elements coupled with real-time movement monitoring and design accommodation for an active response to settlement. Silman’s engineers assessed the ability of the existing structure to accommodate increased loading and addressed several areas where structural modifications to historic fabric were necessary. For example, the original Jeffersonian era vaults and load bearing wall construction required both a verification of capacity as well as innovative design and detailing to create new openings.