Christchurch Central Library construction update
The primary structure of Christchurch’s new Central Library is rising rapidly on site and now, one year from expected completion, is a good opportunity to appreciate the precast concrete shear walls which are central to the building’s seismic performance.
The precast shear walls are part of a post-tensioned hybrid wall system which rocks under seismic loads and self centres to its original position. Supplementary damping devices absorb the seismic energy as the walls rock during an earthquake.
The 25m tall shear walls, each weighing up to 133 tonnes, were cast lying flat on site and lifted into place using a 400-tonne crawler crane with support from a smaller secondary crane – no mean feat!