Base isolation of an existing 10-storey building to enhance earthquake resistance

The Rankine Brown Building at Victoria University of Wellington, New Zealand houses the University Library and is pivotal to the operation of the University. Built in the early 1960s, the building was of innovative form and construction for its time, with long span precast concrete waffle slabs over 10 floors supported on 16 main columns. Three years ago a review of the building structure suggested that increased protection of the building would be required to meet the University's expectation for operational continuity after a moderate or major earthquake event in the Wellington area. This paper outlines: Probable areas of structural yielding in a major earthquake event. Structural analysis for base isolation using earthquake time history records. Details of base isolation bearings. Installation of the base isolation bearings. Other structural details that allow movement of the superstructure to take place due to base isolation.