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Research papers, The University of Auckland Library

In the early morning of 4th September 2010 the region of Canterbury, New Zealand, was subjected to a magnitude 7.1 earthquake. The epicentre was located near the town of Darfield, 40 km west of the city of Christchurch. This was the country’s most damaging earthquake since the 1931 Hawke’s Bay earthquake (GeoNet, 2010). Since 4th September 2010 the region has been subjected to thousands of aftershocks, including several more damaging events such as a magnitude 6.3 aftershock on 22nd February 2011. Although of a smaller magnitude, the earthquake on 22nd February produced peak ground accelerations in the Christchurch region three times greater than the 4th September earthquake and in some cases shaking intensities greater than twice the design level (GeoNet, 2011; IPENZ, 2011). While in September 2010 most earthquake shaking damage was limited to unreinforced masonry (URM) buildings, in February all types of buildings sustained damage. Temporary shoring and strengthening techniques applied to buildings following the Darfield earthquake were tested in February 2011. In addition, two large aftershocks occurred on 13th June 2011 (magnitudes 5.7 and 6.2), further damaging many already weakened structures. The damage to unreinforced and retrofitted clay brick masonry buildings in the 4th September 2010 Darfield earthquake has already been reported by Ingham and Griffith (2011) and Dizhur et al. (2010b). A brief review of damage from the 22nd February 2011 earthquake is presented here

Research papers, The University of Auckland Library

Unreinforced masonry (URM) buildings have repeatedly been shown to perform poorly in large magnitude earthquakes, with both New Zealand and Australia having a history of past earthquakes that have resulted in fatalities due to collapsed URM buildings. A comparison is presented here of the URM building stock and the seismic vulnerability of Christchurch and Adelaide in order to demonstrate the relevance to Australian cities of observations in Christchurch resulting from the 2010/2011 Canterbury earthquake swarm. It is shown that the materials, architecture and hence earthquake strength of URM buildings in both countries is comparable and that Adelaide and other cities of Australia have seismic vulnerability sufficient to cause major damage to their URM buildings should a design level earthquake occur. Such an earthquake is expected to cause major building damage, and fatalities should be expected.

Research papers, The University of Auckland Library

The region in and around Christchurch, encompassing Christchurch city and the Selwyn and Waimakariri districts, contains more than 800 road, rail, and pedestrian bridges. Most of these bridges are reinforced concrete, symmetric, and have small to moderate spans (15–25 m). The 22 February 2011 moment magnitude (Mw) 6.2 Christchurch earthquake induced high levels of localized ground shaking (Bradley and Cubrinovski 2011, page 853 of this issue; Guidotti et al. 2011, page 767 of this issue; Smyrou et al. 2011, page 882 of this issue), with damage to bridges mainly confined to the central and eastern parts of Christchurch. Liquefaction was evident over much of this part of the city, with lateral spreading affecting bridges spanning both the Avon and Heathcote rivers.

Research papers, The University of Auckland Library

This paper presents preliminary field observations on the performance of selected steel structures in Christchurch during the earthquake series of 2010 to 2011. This comprises 6 damaging earthquakes, on 4 September and 26 December 2010, February 22, June 6 and two on June 13, 2011. Most notable of these was the 4 September event, at Ms7.1 and MM7 (MM as observed in the Christchurch CBD) and most intense was the 22 February event at Ms6.3 and MM9-10 within the CBD. Focus is on performance of concentrically braced frames, eccentrically braced frames, moment resisting frames and industrial storage racks. With a few notable exceptions, steel structures performed well during this earthquake series, to the extent that inelastic deformations were less than what would have been expected given the severity of the recorded strong motions. Some hypotheses are formulated to explain this satisfactory performance. http://db.nzsee.org.nz/SpecialIssue/44%284%290297.pdf

Research papers, The University of Auckland Library

The Christchurch region of New Zealand experienced a series of major earthquakes and aftershocks between September 2010 and June 2011 which caused severe damage to the city’s infrastructure. The performance of tilt-up precast concrete buildings was investigated and initial observations are presented here. In general, tilt-up buildings performed well during all three major earthquakes, with mostly only minor, repairable damage occurring. For the in-plane loading direction, both loadbearing and cladding panels behaved exceptionally well, with no significant damage or failure observed in panels and their connections. A limited number of connection failures occurred due to large out-of-plane panel inertia forces. In several buildings, the connections between the panel and the internal structural frame appeared to be the weakest link, lacking in both strength and ductility. This weakness in the out-of-plane load path should be prevented in future designs.

Research papers, University of Canterbury Library

On 22 February 2011,a magnitude Mw 6.3 earthquake occurred with an epicenter located near Lyttelton at about 10km from Christchurch in Canterbury region on the South Island of New Zealand (Figure 1). Since this earthquake occurred in the midst of the aftershock activity which had continued since the 4 September 2010 Darfield Earthquake occurrence, it was considered to be an aftershock of the initial earthquake. Because of the short distance to the city and the shallower depth of the epicenter, this earthquake caused more significant damage to pipelines, traffic facilities, residential houses/properties and multi-story buildings in the central business district than the September 2010 Darfield Earthquake in spite of its smaller earthquake magnitude. Unfortunately, this earthquake resulted in significant number of casualties due to the collapse of multi-story buildings and unreinforced masonry structures in the city center of Christchurch. As of 4 April, 172 casualties were reported and the final death toll is expected to be 181. While it is extremely regrettable that Christchurch suffered a terrible number of victims, civil and geotechnical engineers have this hard-to-find opportunity to learn the response of real ground from two gigantic earthquakes which occurred in less than six months from each other. From geotechnical engineering point of view, it is interesting to discuss the widespread liquefaction in natural sediments, repeated liquefaction within short period and further damage to earth structures which have been damaged in the previous earthquake. Following the earthquake, an intensive geotechnical reconnaissance was conducted to capture evidence and perishable data from this event. The team included the following members: Misko Cubrinovski (University of Canterbury, NZ, Team Leader), Susumu Yasuda (Tokyo Denki University, Japan, JGS Team Leader), Rolando Orense (University of Auckland, NZ), Kohji Tokimatsu (Tokyo Institute of Technology, Japan), Ryosuke Uzuoka (Tokushima University, Japan), Takashi Kiyota (University of Tokyo, Japan), Yasuyo Hosono (Toyohashi University of Technology, Japan) and Suguru Yamada (University of Tokyo, Japan).

Research papers, University of Canterbury Library

Six months after the 4 September 2010 Mw 7.1 Darfield (Canterbury) earthquake, a Mw 6.2 Christchurch (Lyttelton) aftershock struck Christchurch on the 22 February 2011. This earthquake was centred approximately 10km south-east of the Christchurch CBD at a shallow depth of 5km, resulting in intense seismic shaking within the Christchurch central business district (CBD). Unlike the 4 Sept earthquake when limited-to-moderate damage was observed in engineered reinforced concrete (RC) buildings [35], in the 22 February event a high number of RC Buildings in the Christchurch CBD (16.2 % out of 833) were severely damaged. There were 182 fatalities, 135 of which were the unfortunate consequences of the complete collapse of two mid-rise RC buildings. This paper describes immediate observations of damage to RC buildings in the 22 February 2011 Christchurch earthquake. Some preliminary lessons are highlighted and discussed in light of the observed performance of the RC building stock. Damage statistics and typical damage patterns are presented for various configurations and lateral resisting systems. Data was collated predominantly from first-hand post-earthquake reconnaissance observations by the authors, complemented with detailed assessment of the structural drawings of critical buildings and the observed behaviour. Overall, the 22 February 2011 Mw 6.2 Christchurch earthquake was a particularly severe test for both modern seismically-designed and existing non-ductile RC buildings. The sequence of earthquakes since the 4 Sept 2010, particularly the 22 Feb event has confirmed old lessons and brought to life new critical ones, highlighting some urgent action required to remedy structural deficiencies in both existing and “modern” buildings. Given the major social and economic impact of the earthquakes to a country with strong seismic engineering tradition, no doubt some aspects of the seismic design will be improved based on the lessons from Christchurch. The bar needs to and can be raised, starting with a strong endorsement of new damage-resisting, whilst cost-efficient, technologies as well as the strict enforcement, including financial incentives, of active policies for the seismic retrofit of existing buildings at a national scale.

Research papers, The University of Auckland Library

The M7.1 Darfield earthquake shook the town of Christchurch (New Zealand) in the early morning on Saturday 4th September 2010 and caused damage to a number of heritage unreinforced masonry buildings. No fatalities were reported directly linked to the earthquake, but the damage to important heritage buildings was the most extensive to have occurred since the 1931 Hawke‟s Bay earthquake. In general, the nature of damage was consistent with observations previously made on the seismic performance of unreinforced masonry buildings in large earthquakes, with aspects such as toppled chimneys and parapets, failure of gables and poorly secured face-loaded walls, and in-plane damage to masonry frames all being extensively documented. This report on the performance of the unreinforced masonry buildings in the 2010 Darfield earthquake provides details on typical building characteristics, a review of damage statistics obtained by interrogating the building assessment database that was compiled in association with post-earthquake building inspections, and a review of the characteristic failure modes that were observed.

Research papers, The University of Auckland Library

The sequence of earthquakes that has greatly affected Christchurch and Canterbury since September 2010 has again demonstrated the need for seismic retrofit of heritage unreinforced masonry buildings. Commencing in April 2011, the damage to unreinforced stone masonry buildings in Christchurch was assessed and recorded with the primary objective being to document the seismic performance of these structures, recognising that they constitute an important component of New Zealand’s heritage architecture. A damage statistics database was compiled by combining the results of safety evaluation placarding and post-earthquake inspections, and it was determined that the damage observed was consistent with observations previously made on the seismic performance of stone masonry structures in large earthquakes. Details are also given on typical building characteristics and on failure modes observed. Suggestions on appropriate seismic retrofit and remediation techniques are presented, in relation also to strengthening interventions that are typical for similar unreinforced stone masonry structures in Europe.

Research papers, University of Canterbury Library

A magnitude 6.3 earthquake struck the city of Christchurch at 12:51pm on Tuesday 22 February 2011. The earthquake caused 182 fatalities, a large number of injuries, and resulted in widespread damage to the built environment, including significant disruption to the lifelines. The event created the largest lifeline disruption in a New Zealand city in 80 years, with much of the damage resulting from extensive and severe liquefaction in the Christchurch urban area. The Christchurch earthquake occurred when the Canterbury region and its lifelines systems were at the early stage of recovering from the 4 September 2010 Darfield (Canterbury) magnitude 7.1 earthquake. This paper describes the impact of the Christchurch earthquake on lifelines by briefly summarising the physical damage to the networks, the system performance and the operational response during the emergency management and the recovery phase. Special focus is given to the performance and management of the gas, electric and road networks and to the liquefaction ejecta clean-up operations that contributed to the rapid reinstatement of the functionality of many of the lifelines. The water and wastewater system performances are also summarized. Elements of resilience that contributed to good network performance or to efficient emergency and recovery management are highlighted in the paper.

Research papers, University of Canterbury Library

The 22 February 2011, Mw6.2-6.3 Christchurch earthquake is the most costly earthquake to affect New Zealand, causing 181 fatalities and severely damaging thousands of residential and commercial buildings, and most of the city lifelines and infrastructure. This manuscript presents an overview of observed geotechnical aspects of this earthquake as well as some of the completed and on-going research investigations. A unique aspect, which is particularly emphasized, is the severity and spatial extent of liquefaction occurring in native soils. Overall, both the spatial extent and severity of liquefaction in the city was greater than in the preceding 4th September 2010 Darfield earthquake, including numerous areas that liquefied in both events. Liquefaction and lateral spreading, variable over both large and short spatial scales, affected commercial structures in the Central Business District (CBD) in a variety of ways including: total and differential settlements and tilting; punching settlements of structures with shallow foundations; differential movements of components of complex structures; and interaction of adjacent structures via common foundation soils. Liquefaction was most severe in residential areas located to the east of the CBD as a result of stronger ground shaking due to the proximity to the causative fault, a high water table approximately 1m from the surface, and soils with composition and states of high susceptibility and potential for liquefaction. Total and differential settlements, and lateral movements, due to liquefaction and lateral spreading is estimated to have severely compromised 15,000 residential structures, the majority of which otherwise sustained only minor to moderate damage directly due to inertial loading from ground shaking. Liquefaction also had a profound effect on lifelines and other infrastructure, particularly bridge structures, and underground services. Minor damage was also observed at flood stop banks to the north of the city, which were more severely impacted in the 4th September 2010 Darfield earthquake. Due to the large high-frequency ground motion in the Port hills numerous rock falls and landslides also occurred, resulting in several fatalities and rendering some residential areas uninhabitable.

Research papers, University of Canterbury Library

This manuscript provides a critical examination of the ground motions recorded in the near-source region resulting from the 22 February 2011 Christchurch earthquake. Particular attention is given to reconciling the observed spatial distribution of ground motions in terms of physical phenomena related to source, path and site effects. The large number of near-source observed strong ground motions show clear evidence of: forward-directivity, basin generated surface waves, liquefaction and other significant nonlinear site response. The pseudo-acceleration response spectra (SA) amplitudes and significant duration of strong motions agree well with empirical prediction models, except at long vibration periods where the influence of basin-generated surface waves and nonlinear site response are significant and not adequately accounted for in empirical SA models. Pseudo-acceleration response spectra are also compared with those observed in the 4 September 2010 Darfield earthquake and routine design response spectra used in order to emphasise the amplitude of ground shaking and elucidate the importance of local geotechnical characteristics on surface ground motions. The characteristics of the observed vertical component accelerations are shown to be strongly dependent on source-to-site distance and are comparable with those from the 4 September 2010 Darfield earthquake, implying the large amplitudes observed are simply a result of many observations at close distances rather than a peculiar source effect.

Research papers, Lincoln University

The New Zealand Kellogg Rural Leaders Programme develops emerging agribusiness leaders to help shape the future of New Zealand agribusiness and rural affairs. Lincoln University has been involved with this leaders programme since 1979 when it was launched with a grant from the Kellogg Foundation, USA.At 4.35am on 4th September 2010, Canterbury was hit by an earthquake measuring 7.1 on the Richter scale. On 22nd February 2011 and 13th June 2011 a separate fault line approximately 35km from the first, ruptured to inflict two further earthquakes measuring 6.3 and 6.0 respectively. As a direct result of the February earthquake, 181 people lost their lives. Some commentators have described this series of earthquakes as the most expensive global insurance event of all time. These earthquakes and the more than 7000 associated aftershocks have had a significant physical impact on parts of Canterbury and virtually none on others. The economic, social and emotional impacts of these quakes spread across Canterbury and beyond. Waimakariri district, north of Christchurch, has reflected a similar pattern, with over 1400 houses requiring rebuild or substantial repair, millions of dollars of damage to infrastructure, and significant social issues as a result. The physical damage in Waimakiriri District was predominately in parts of Kaiapoi, and two small beach settlements, The Pines and Kairaki Beach with pockets elsewhere in the district. While the balance of the district is largely physically untouched, the economic, social, and emotional shockwaves have spread across the district. Waimakariri district consists of two main towns, Rangiora and Kaiapoi, a number of smaller urban areas and a larger rural area. It is considered mid-size in the New Zealand local government landscape. This paper will explore the actions and plans of Waimakiriri District Council (WDC) in the Emergency Management Recovery programme to provide context to allow a more detailed examination of the planning processes prior to, and subsequent to the earthquakes. This study looked at documentation produced by WDC, applicable legislation and New Zealand Emergency Management resources and other sources. Key managers and elected representatives in the WOC were interviewed, along with a selection of governmental and nongovernmental agency representatives. The interview responses enable understanding of how central Government and other local authorities can benefit from these lessons and apply them to their own planning. It is intended that this paper will assist local government organisations in New Zealand to evaluate their planning processes in light of the events of 2010/11 in Canterbury and the lessons from WDC.

Research papers, University of Canterbury Library

The 4th of September 2010 Mw 7.1 Darfield (Canterbury) earthquake had generated significant ground shaking within the Christchurch Central Business District (CBD). Despite the apparently significant shaking, the observed structural damage for pre-1970s reinforced concrete (RC) buildings was indeed limited and lower than what was expected for such typology of buildings. This paper explores analytically and qualitatively the different aspects of the "apparent‟ good seismic performance of the pre-1970s RC buildings in the Christchurch CBD, following the earthquake reconnaissance survey by the authors. Damage and building parameters survey result, based on a previously established inventory of building stock of these non-ductile RC buildings, is briefly reported. From an inventory of 75 buildings, one building was selected as a numerical case-study to correlate the observed damage with the non-linear analyses. The result shows that the pre-1970s RC frame buildings performed as expected given the intensity of the ground motion shaking during the Canterbury earthquake. Given the brittle nature of this type of structure, it was demonstrated that more significant structural damage and higher probability of collapse could occur when the buildings were subjected to alternative input signals with different frequency content and duration characteristics and still compatible to the seismicity hazard for Christchurch CBD.

Research papers, Lincoln University

On September the 4th 2010 and February 22nd 2011 the Canterbury region of New Zealand was shaken by two massive earthquakes. This paper is set broadly within the civil defence and emergency management literature and informed by recent work on community participation and social capital in the building of resilient cities. Work in this area indicates a need to recognise both the formal institutional response to the earthquakes as well as the substantive role communities play in their own recovery. The range of factors that facilitate or hinder community involvement also needs to be better understood. This paper interrogates the assumption that recovery agencies and officials are both willing and able to engage communities who are themselves willing and able to be engaged in accordance with recovery best practice. Case studies of three community groups – CanCERN, Greening the Rubble and Gap Filler – illustrate some of the difficulties associated with becoming a community during the disaster recovery phase. Based on my own observations and experiences, combined with data from approximately 50 in-depth interviews with Christchurch residents and representatives from community groups, the Christchurch City Council, the Earthquake Commission and so on, this paper outlines some practical strategies emerging communities may use in the early disaster recovery phase that then strengthens their ability to ‘participate’ in the recovery process.

Research papers, University of Canterbury Library

At 4.35am on Saturday 4 September 2010, a magnitude 7.1 earthquake struck near the township of Darfield in Canterbury leading to widespread damage in Christchurch and the wider central Canterbury region. Though it was reported no lives were lost, that was not entirely correct. Over 3,000 animals perished as a result of the earthquake and 99% of these deaths would have been avoidable if appropriate mitigation measures had been in place. Deaths were predominantly due to zoological vulnerability of birds in captive production farms. Other problems included lack of provision of animal welfare at evacuation centres, issues associated with multiple lost and found pet services, evacuation failure due to pet separation and stress impact on dairy herds and associated milk production. The Canterbury Earthquake has highlighted concerns over a lack of animal emergency welfare planning and capacity in New Zealand, an issue that is being progressed by the National Animal Welfare Emergency Management Group. As animal emergency management becomes better understood by emergency management and veterinary professionals, it is more likely that both sectors will have greater demands placed upon them by national guidelines and community expectations to ensure provisions are made to afford protection of animals in times of disaster. A subsequent and more devastating earthquake struck the region on Monday 22 February 2011; this article however is primarily focused on the events pertaining to the September 4 event.

Research papers, Lincoln University

There is a critical strand of literature suggesting that there are no ‘natural’ disasters (Abramovitz, 2001; Anderson and Woodrow, 1998; Clarke, 2008; Hinchliffe, 2004). There are only those that leave us – the people - more or less shaken and disturbed. There may be some substance to this; for example, how many readers recall the 7.8 magnitude earthquake centred in Fiordland in July 2009? Because it was so far away from a major centre and very few people suffered any consequences, the number is likely to be far fewer than those who remember (all too vividly) the relatively smaller 7.1 magnitude Canterbury quake of September 4th 2010 and the more recent 6.3 magnitude February 22nd 2011 event. One implication of this construction of disasters is that seismic events, like those in Canterbury, are as much socio-political as they are geological. Yet, as this paper shows, the temptation in recovery is to tick boxes and rebuild rather than recover, and to focus on hard infrastructure rather than civic expertise and community involvement. In this paper I draw upon different models of community engagement and use Putnam’s (1995) notion of ‘social capital’ to frame the argument that ‘building bridges’ after a disaster is a complex blend of engineering, communication and collaboration. I then present the results of a qualitative research project undertaken after the September 4th earthquake. This research helps to illustrate the important connections between technical rebuilding, social capital, recovery processes and overall urban resilience.

Research papers, University of Canterbury Library

Surface rupture of the previously unrecognised Greendale Fault extended west-east for ~30 km across alluvial plains west of Christchurch, New Zealand, during the Mw 7.1 Darfield (Canterbury) earthquake of September 2010. Surface rupture displacement was predominantly dextral strike-slip, averaging ~2.5 m, with maxima of ~5 m. Vertical displacement was generally less than 0.75 m. The surface rupture deformation zone ranged in width from ~30 to 300 m, and comprised discrete shears, localised bulges and, primarily, horizontal dextral flexure. About a dozen buildings, mainly single-storey houses and farm sheds, were affected by surface rupture, but none collapsed, largely because most of the buildings were relatively flexible and resilient timber-framed structures and also because deformation was distributed over a relatively wide zone. There were, however, notable differences in the respective performances of the buildings. Houses with only lightly-reinforced concrete slab foundations suffered moderate to severe structural and non-structural damage. Three other buildings performed more favourably: one had a robust concrete slab foundation, another had a shallow-seated pile foundation that isolated ground deformation from the superstructure, and the third had a structural system that enabled the house to tilt and rotate as a rigid body. Roads, power lines, underground pipes, and fences were also deformed by surface fault rupture and suffered damage commensurate with the type of feature, its orientation to the fault, and the amount, sense and width of surface rupture deformation.

Research papers, University of Canterbury Library

This thesis investigates the relationship between the apocalyptic narrative and the postmodern novel. It explores and builds on Patricia Waugh‟s hypothesis in Practising Postmodernism: Reading Modernism (1992) which suggests that that the postmodern is characterised by an apocalyptic sense of crisis, and argues that there is in fact a strong relationship between the apocalyptic and the postmodern. It does so through an exploration of apocalyptic narratives and themes in five postmodern novels. It also draws on additional supporting material which includes literary and cultural theory and criticism, as well as historical theory. In using the novel as a medium through which to explore apocalyptic narratives, this thesis both assumes and affirms the novel‟s importance as a cultural artefact which reflects the concerns of the age in which it is written. I suggest that each of the novels discussed in this thesis demonstrates the close relationship between the apocalyptic and the postmodern through society‟s concern over the direction of history, the validity of meta-narratives, and other cultural phenomenon, such as war, the development of nuclear weaponry, and terrorism. Although the scope of this thesis is largely confined to the historical-cultural epoch known as postmodernity, it also draws on literature and cultural criticism from earlier periods so as to provide a more comprehensive framework for investigating apocalyptic ideas and their importance inside the postmodern novel. A number of modernist writers are therefore referred to or quoted throughout this thesis, as are other important thinkers from preceding periods whose ideas are especially pertinent. The present thesis was researched and written between March 2010 and August 2011 and is dedicated to all of those people who lost their lives in the apocalyptic events of the February 22nd Christchurch earthquake.