Tipping Mar's vertically post-tensioned concrete shear walls in the 164-ft-tall San Francisco Public Utilities Commission Headquarters is the most ambitious—and tallest—example to date of a family of lateral-load-resisting structures designed to minimize damage in a major earthquake and allow immediate reoccupancy. U.S. structural practitioners and researchers have been developing the self-centering systems, modeled after PT bridge construction, for about a decade.
Self-centering structures, when designed in structural steel, have become known as "rocking frames." In addition to concrete systems, there are examples of self-centering PT structures in precast concrete and in composite steel-and-precast structures.