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Glazing and window systems in New Zealand have been shown to be susceptible to significant damage as evidenced by the past decade of earthquakes. The seismic performance of glazing and window systems has resulted in considerable financial loss, disruption in business and physical injuries following earthquakes. In order to investigate the vulnerability of residential windows in typical light timber framed buildings racking testing was conducted on six wall configurations. Numerous observations of window performance were made during the testing and from these results fragility functions were developed for timber and aluminium framed windows. These fragility functions suggest that even at low displacement levels damage can occur to windows that can potentially affect weather-tightness and require repairs following an earthquake. These functions can inform decisions around designing for resiliency in residential structures in New Zealand.

The goal of this study is to develop a racking model of plasterboard-sheathed timber walls as part of the efforts towards performance-based seismic engineering of low-rise light timber-framed (LTF) residential buildings in New Zealand. Residential buildings in New Zealand are primarily stand-alone low-rise LTF buildings, and their bracing elements are commonly plasterboard-sheathed LTF walls. It is an essential part of performance-based seismic designs of LTF buildings to be able to simulate the racking performance of plasterboard walls. In this study, racking test results of 12 plasterboard walls were collected and studied to gain insight into the seismic performance of plasterboard-sheathed LTF walls. The racking performance of these walls was examined in terms of stiffness/strength degradation, displacement capacity, superposition applicability and failure mechanisms. Subsequently, a mathematical analysis model for simulating racking performance of LTF plasterboard walls is developed and presented. The developed racking model is a closed-form wall model and could be easily used for conducting three-dimensional non-linear push-over studies of seismic performance of LTF buildings.

The author inspected 18 racking installations at various food storage facilities in Christchurch for damage from the 4th September 2010 Darfield Earthquake. The type of racking installations and damage suffered are listed with some photographs of specific damage. The damage ranged from minor to complete collapse with large product loss. Although inspection access was limited, the collapse mechanism for racking installations is assessed and suggested. The damage inspected indicated some variation in the application of design approaches and potential areas where the behaviour of rack structures may not have been fully understood during design. General conclusions are drawn from the damage inspections, and suggestions offered for the refinement and improvement of racking design approaches.

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.

Modern industrial pallet racking systems in use in New Zealand are adaptions of overseas design, using thin walled cold formed sections. These sections are not generally considered suitable for plastic deformations, or resistance to seismically induced loadings. This paper reviews full scale shaking table tests reported by Rack Manufacturers Institute, Pittsburg, (R.M.I.) in 1980, and comments on the applicability of the results to the seismic design philosophy embodied in NZS 4203. Seismic performance criteria (not strictly the same as for building structures) are proposed, and design approaches suggested that will enable the capacity design requirements of NZS 4203 to be considered, while keeping with the cold formed sections traditionally used for pallet rack construction.

This paper summarises the results obtained from testing 18 reinforced masonry wall panels under racking load. The programme included tests on both RBM and Hollow Cell types of brick construction under slow cyclic loading. It is shown that satisfactory ductility can be obtained from brick masonry walls if sufficient horizontal steel is provided to carry the full shear load, and if the critical compression zones at the bottom corners of the wall are confined by the use of thin reinforcing plates in the bottom few mortar courses. Without these precautions severe load degradation occurs under successive load reversals.