The new tower links Terminal 1 with Terminal 2 in a cutting-edge facility for air traffic controllers and FAA staff. The project involved the preparation of the conceptual design and design-build bridging documents for the replacement tower. R+C was responsible for the development of the project-specific seismic design criteria, which required close collaboration with SFO and FAA stakeholders since the design involved a non-prescriptive (performance-based) approach intended to provide Immediate Occupancy in the Design Basis EQ. R+C performed nonlinear response history analysis to develop the innovative structural concept, which includes unbonded vertical post-tensioning in a concrete core—this allows the tower to re-center itself, reducing residual post-earthquake displacement.R+C provided structural and geotechnical engineering services related to the seismic design of the new tower and also provided peer review services to the design-build team.