		2006 NZSEE Conference
	Abstracts

Keynote Address Learning from Hawke's Bay 1931 Earthquake Performance Assessment and Retrofit Decision Making for Risk Mitigation Behaviour of Walls and Piers Understanding Reinforced Concrete Behaviour Modelling Earthquake Performance Earthquake Performance Poster Papers Design and Development

Effects of Significant Earthquakes on the Development of Earthquake Engineering

Robert Reitherman

The development of earthquake engineering around the world over the past century has been influenced by several types of causes other than disastrous earthquakes. An earthquake that was large in seismological (e.g. magnitude) or engineering (e.g. destructiveness) measures may have had little effect on engineering tools developed to contend with the earthquake problem. The history of earthquake engineering is not merely a set of events rigidly tied to a chronology of major earthquakes. Nonetheless, some significant earthquakes have been step function events on the graph of long-term progress in earthquake engineering. In this brief historical review, the following seminal earthquakes are discussed: 1906 California, United States; 1908 Reggio-Messina, Italy; 1923 Kanto, Japan; 1931 Mach and 1935 Quetta, India; 1931 Hawke’s Bay, New Zealand. Rather than an all-encompassing theory as to why some earthquakes more than others have been influential in the development of earthquake engineering, the author’s historical research leads to the conclusion that it is important to examine the unique historical context of each earthquake.

Paper P37: [Read]

Adapting the Structural Design Actions Standard for the Seismic Design of New Industrial Plant

Graeme Lindup

There are overseas publications that have considered the differences in the typical structural systems necessary to support the equipment and distributive systems needed to process industrial feedstock. Current standards as ASCE 7 and FEMA 450 incorporate these in a specific manner relating to the design of industrial plant. The design engineer for industrial structures is required to develop a feel for how nonbuilding structures behave with a shortage of research into their earthquake performance. A degree of conservatism in the design approach for these structures is warranted until their behaviour is more fully documented and researched. This paper takes the opportunity to review AS/NZS 1170 and adapt these overseas guidelines for the seismic design of new industrial plant in New Zealand.

Paper P38: [Read]

Critical Earthquake Risk Detailing in New Zealand’s Multi-storey Building Stock: Understanding and Improving the Current Perception

Hannah Schofield, Jason Ingham and Stefano Pampanin

This paper presents a summary of preliminary findings on critical earthquake risk detailing in New Zealand’s multi-storey building stock, derived from discussions with leading New Zealand structural consultants, material suppliers, archivists and historians. Critical details are presented with reference to steel, unreinforced masonry and concrete and precast concrete construction, based upon their prevalence throughout New Zealand and the perceived degree of seismic risk associated with the details. This study is part of an on-going six-year FRST-funded research project on Seismic Retrofit Solutions for NZ, carried out by the Universities of Auckland and Canterbury. The main scope of the project is to develop cost-effective seismic retrofit solutions appropriate to New Zealand’s unique construction practices and to prepare a seismic retrofit manual to be distributed to practising engineers as a companion document to the recently released NZSEE guidelines for assessment of earthquake risk buildings. A brief outline of the project is also presented, with further information available on the associated project website.

Paper P39: [Read]

A Design Guide for High Level Storage Racking with Public Access

Graeme Beattie

This paper describes the development of a Guide for high level storage racking in areas where the public have access, such as supermarkets, discount stores and home handyman stores. The Building Industry Authority (now the Department of Building and Housing, Building Controls Group) has determined that such systems are a permanent part of a building and therefore must satisfy the requirements of the NZ Building Code.

The Guide has been developed after extensive review of overseas practices and standards, inelastic computer modelling of rack response and laboratory testing of components and complete systems and is available for use by designers of new racking systems. The Guide also contains information on stocking recommendations on racks and an operational guide.

Paper P40: [Read]

The Structural Requirements of Emergency Operations Centres for Earthquake

David Brunsdon, Andrew King and Michael Cathie

The co-ordination of activities following emergency events by civil defence emergency management agencies and lifeline utilities is typically undertaken from emergency operations centres (EOCs) or control centres. They are part of a wider category of ‘structures with special post-disaster functions’. The post-earthquake structural design requirements for these structures are framed by both the Civil Defence Emergency Management (CDEM) Act and the loading standards AS/NZS 1170 Part 0 (general) and NZS 1170 Part 5 (earthquake). There are several aspects to be considered in specifying or evaluating the post-earthquake functionality of a building or facility, beyond just life safety aspects.

Many CDEM and Lifeline utility EOCs and local council buildings are located in existing buildings of 20 years or older in age that were designed for ‘ordinary’ usage. In terms of seismic performance, many of those designed in accordance with the minimum requirements of loadings standards in the NZS 4203 series are likely to fall short of the requirements of the new earthquake loadings standard NZS 1170.5 for ‘structures with special post-disaster functions’, particularly with respect to Serviceability Limit State response.

This paper outlines the expectations and specific requirements of both the CDEM Act and the relevant new earthquake loadings standards AS/NZS 1170 Part 0 and NZS 1170 Part 5 with respect to post-disaster facilities. Issues for practitioners are highlighted. The need for additional guidance on what structures fall within the classification of ‘structures with special post-disaster functions’ is also noted.

Paper P41: [Read]

Experimental Development and Analysis of a High Force/volume Extrusion Damper

Geoffrey Rodgers, Caleb Denmead, Nicholas Leach, Geoff Chase and John Mander

Energy dissipation is critical to minimizing damage and degradation of structural connections due to earthquakes, wind loads or heavy traffic. Supplemental dampers are a means of repeatedly dissipating energy without damage to the structure. This research develops and analyses lead extrusion dampers as a potentially inexpensive method of providing this damping. However, widespread application in structural connections, requires small devices with a very high force to device volume ratio. A variety of prototype dampers were designed and tested to characterise their force-displacement behaviour and produce trade-off curves relating device geometry to force capacity. Results show that prestressing the working material is critical to obtain an approximately square hysteresis loop and maximum energy dissipation. Test results produced very different relationships than those reported for similar extrusion processes, indicating that yield stresses, rather than extrusion properties, dominate behaviour. Peak forces of 200-350kN were obtained for devices that were all able to fit within standard structural connections. The overall results indicate that repeatable, optimal energy dissipation can be obtained in a compact device to minimize damage to critical buildings and infrastructure.

Paper P42: [Read]