Observed performance of industrial pallet rack storage systems in the Canterbury earthquakes

Abstract

In Christchurch, the industrial sectors with storage facilities incurred heavy economic loss due to the collapse of pallet rack systems and loss of contents during the recent the Darfield (2010) and Lyttleton (2011) earthquakes. The failure of such systems could be attributed to various reasons including inadequate design, inappropriate operational conditions, improper installation and lack of maintenance. This paper describes possible sources of damage in pallet racks due to earthquake action, which eventually could trigger the collapse failure mode of the storage system during a severe aftershock. Various racking manufacturers and retail owners were consulted to establish the pre-event condition and loading of the systems and the response of the systems in both ‘publicly accessible’ and ‘industrial’ situations. Investigations by the authors highlighted an apparent lack of consistent national control over the design and construction of racking systems. Progress towards the publication of a revised and extended Design Guide is also described.