Perimeter Moment resisting steel frames (PMRSFs) are a commonly used seismic resisting system, placed around the perimeter of the building for maximum torsional stiffness. They are typically designed as “strong column weak beam” systems with fixed column bases. When subjected to severe earthquake demand, sufficient to push the beams into the inelastic range, it is expected that plastic hinging at the column bases will occur. However, the response of PMRSF systems to the severe 2010/2011 Christchurch earthquake series did not generate column base hinging in systems which exhibited beam yielding.
Ingham and Biggs were in Christchurch during the M6.3, 22 February 2011 earthquake and Moon arrived the next day. They were enlisted by officials to provide rapid assessment of buildings within the Central Business District (CBD). In addition, they were asked to: 1) provide a rapid assessment of the numbers and types of buildings that had been damaged, and 2) identify indicator buildings that represent classes of structures that can be used to monitor changing conditions for each class following continuing aftershocks and subsequent damage. This paper explains how transect methodology was incorporated into the rapid damage assessment that was performed 48 hours after the earthquake. Approximately 300 buildings were assessed using exterior Level 1 reporting techniques. That data was used to draw conclusions on the condition of the entire CBD of approximately 4400 buildings. In the context of a disaster investigation, a transect involves traveling a selected path assessing the condition of the buildings and documenting the class of each building, and using the results in conjunction with prior knowledge relating to the overall population of buildings affected in the area of the study. Read More: http://ascelibrary.org/doi/abs/10.1061/9780784412640.033
The performance of retrofitted unreinforced masonry (URM) bearing wall buildings in Christchurch is examined, considering ground motion recordings from multiple events. Suggestions for how the experiences in Christchurch might be relevant to retrofit practices common to New Zealand, U.S. and Canada are also provided. Whilst the poor performance of unretrofitted URM buildings in earthquakes is well known, much less is known about how retrofitted URM buildings perform when subjected to strong ground shaking.
The Canterbury earthquakes in New Zealand caused significant damage to a number of reinforced concrete (RC) walls and subsequent research that has been conducted to investigate the design provisions for lightly reinforced RC walls and precast concrete wall connection details is presented. A combination of numerical modelling and large-scale tests were conducted to investigate the seismic behaviour of lightly RC walls. The model and test results confirmed the observed behaviour of an RC wall building in Christchurch that exhibited a single flexural crack and also raised questions regarding the ability of current minimum reinforcement requirements to prevent the concentration of inelastic deformation at a small number of flexural cracks. These findings have led to changes to the minimum vertical reinforcement limits for RC walls in in the Concrete Structures Standard (NZS 3101:2006), with increased vertical reinforcement required in the end region of ductile RC walls. An additional series of wall tests were conducted to investigate the seismic behaviour of panel-to-foundation connections in singly reinforced precast concrete panels that often lack robustness. Both in-plane and out-of-plane panel tests were conducted to assess both grouted connections and dowel connections that use shallow embedded inserts. The initial test results have confirmed some of the previously identified vulnerabilities and tests are ongoing to refine the connection designs. http://www.aees.org.au/downloads/conference-papers/2015-2/
During the 2010/2011 Canterbury earthquakes, Reinforced Concrete Frame with Masonry Infill (RCFMI) buildings were subjected to significant lateral loads. A survey conducted by Christchurch City Council (CCC) and the Canterbury Earthquake Recovery Authority (CERA) documented 10,777 damaged buildings, which included building characteristics (building address, the number of storeys, the year of construction, and building use) and post-earthquake damage observations (building safety information, observed damage, level of damage, and current state of the buildings). This data was merged into the Canterbury Earthquake Building Assessment (CEBA) database and was utilised to generate empirical fragility curves using the lognormal distribution method. The proposed fragility curves were expected to provide a reliable estimation of the mean vulnerability for commercial RCFMI buildings in the region. http://www.13thcms.com/wp-content/uploads/2017/05/Symposium-Info-and-Presentation-Schedule.pdf VoR - Version of Record
The city of Christchurch has experienced over 10,000 aftershocks since the 4th of September 2010 earthquake of which approximately 50 have been greater than magnitude 5. The damage caused to URM buildings in Christchurch over this sequence of earthquakes has been well documented. Due to the similarity in age and construction of URM buildings in Adelaide, South Australia and Christchurch (they are sister cities, of similar age and heritage), an investigation was conducted to learn lessons for Adelaide based on the Christchurch experience. To this end, the number of URM buildings in the central business districts of both cities, the extent of seismic strengthening that exists in both cities, and the relative earthquake hazards for both cities were considered. This paper will report on these findings and recommend strategies that the city of Adelaide could consider to significantly reduce the seismic risk posed by URM buildings in future earthquake.
The Darfield earthquake caused widespread damage in the Canterbury region of New Zealand, with the majority of damage resulting from liquefaction and lateral spreading. One of the worst hit locations was the small town of Kaiapoi north of Christchurch, an area that has experienced liquefaction during past events and has been identified as highly susceptible to liquefaction. The low lying town sits on the banks of the Kaiapoi River, once a branch of the Waimakariri, a large braided river transporting gravelly sediment. The Waimakariri has been extensively modified both by natural and human processes, consequently many areas in and around the town were once former river channels.
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
Terminus calving of icebergs is a common mass-loss mechanism from water-terminating glaciers globally, including the lake-calving glaciers in New Zealand’s central Southern Alps. Calving rates can increase dramatically in response to increases in ice velocity and/or retreat of the glacier margin. Here, we describe a large calving event (c. 4.5 × 106 m3) observed at Tasman Glacier, which initiated around 30 min after the MW 6.2 Christchurch earthquake of 22 February 2011. The volume of this calving event was equalled or exceeded only once in a subsequent 13-month-long study. While the temporal association with the earthquake remains intriguing, the effects of any preconditioning factors remain unclear.
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.
Churches are an important part of New Zealand's historical and architectural heritage. Various earthquakes around the world have highlighted the significant seismic vulnerability of religious buildings, with the extensive damage that occurred to stone and clay-brick unreinforced masonry churches after the 2010-2011 Canterbury earthquakes emphasising the necessity to better understand this structural type. Consequently, a country-wide inventory of unreinforced masonry churches is here identified. After a bibliographic and archival investigation, and a 10 000 km field trip, it is estimated that currently 297 unreinforced masonry churches are present throughout New Zealand, excluding 12 churches demolished in Christchurch because of heavy damage sustained during the Canterbury earthquake sequence. The compiled database includes general information about the buildings, their architectural features and structural characteristics, and any architectural and structural transformations that have occurred in the past. Statistics about the occurrence of each feature are provided and preliminary interpretations of their role on seismic vulnerability are discussed. The list of identified churches is reported in annexes, supporting their identification and providing their address.
The progressive damage and subsequent demolition of unreinforced masonry (URM) buildings arising from the Canterbury earthquake sequence is reported. A dataset was compiled of all URM buildings located within the Christchurch CBD, including information on location, building characteristics, and damage levels after each major earthquake in this sequence. A general description of the overall damage and the hazard to both building occupants and to nearby pedestrians due to debris falling from URM buildings is presented with several case study buildings used to describe the accumulation of damage over the earthquake sequence. The benefit of seismic improvement techniques that had been installed to URM buildings is shown by the reduced damage ratios reported for increased levels of retrofit. Demolition statistics for URM buildings in the Christchurch CBD are also reported and discussed. VoR - Version of Record
"The nuclear meltdown at Fukushima ... the Fonterra botulism scare ... the Christchurch earthquakes – in all these recent crises the role played by scientists has been under the spotlight. What is the first duty of scientists in a crisis – to the government, to their employer, or to the wider public desperate for information? And what if these different objectives clash? In this penetrating BWB Text, leading scientist Shaun Hendy finds that in New Zealand, the public obligation of the scientist is often far from clear and that there have been many disturbing instances of scientists being silenced. Experts who have information the public seeks, he finds, have been prevented from speaking out. His own experiences have led him to conclude that New Zealanders have few scientific institutions that feel secure enough to criticise the government of the day." - Publisher information. http://librarysearch.auckland.ac.nz/UOA2_A:Combined_Local:uoa_alma21259423940002091
The role of belonging in post-disaster environments remains an under-theorised concept, particularly regarding refugee populations. This paper presents a qualitative study with 101 refugee-background participants from varying communities living in Christchurch, New Zealand, about their perspectives and responses to the Canterbury earthquakes of 2010–11. Participants spoke of how a sense of belonging as individuals and as a wider community was important in the recovery effort, and highlighted the multiple ways in which they understood this concept. Their comments demonstrate how belonging can have contextual, chronological and gendered dimensions that can help inform effective and resonant disaster responses with culturally and linguistically diverse populations. This analysis also illustrates how the participants' perspectives of belonging shifted over time, and discusses the corresponding role of social work in supporting post-disaster recovery through the concepts of civic, ethno and ethnic-based belonging. AM - Accepted Manuscript
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.
Following the 2010/2011 Canterbury, New Zealand earthquakes, a detailed door-to-door survey was conducted in the Christchurch region to establish the earthquake performance of lightweight timber-framed residential dwellings with a masonry veneer external cladding system. The post-earthquake survey involved documenting the condition of dwellings in areas that had experienced different levels of earthquake shaking, allowing comparison between the performance of different veneer systems and different shaking intensities. In total, just fewer than 1,100 residential dwellings were inspected throughout the wider Christchurch area. The survey included parameters such as level of veneer damage, type of veneer damage, observed crack widths, and level of repair required. It is concluded that based on observed earthquake performance at the shaking intensities matching or exceeding ultimate limit state loading, the post-1996 veneer fixing details performed satisfactorily and continued use of the detail is recommended without further modification. AM - Accepted Manuscript
During the Christchurch earthquake of February 2011, several midrise reinforced concrete masonry (RCM) buildings showed performance levels that fall in the range of life safety to near collapse. A case study of one of these buildings, a six-story RCM building deemed to have reached the near collapse performance level, is presented in this paper. The RCM walls on the second floor failed due to toe crushing, reducing the building's lateral resistance in the east–west direction. A three-dimensional (3-D) nonlinear dynamic analysis was conducted to simulate the development of the governing failure mechanism. Analysis results showed that the walls that were damaged were subjected to large compression loads during the earthquake, which caused an increase in their in-plane lateral strength but reduced their ductility capacity. After toe crushing failure, axial instability of the model was prevented by a redistribution of gravity loads. VoR - Version of Record
A number of field testing techniques, such as standard penetration test (SPT), cone penetration test (CPT), and Swedish weight sounding (SWS), are popularly used for in-situ characterisation. The screw driving sounding (SDS) method, which has been recently developed in Japan, is an improved version of the SWS technique and measures more parameters, including the required torque, load, speed of penetration and rod friction; these provide more robust way of characterising soil stratigraphy. It is a cost-efficient technique which uses a machine-driven and portable device, making it ideal for testing in small-scale and confined areas. Moreover, with a testing depth of up to 10-15m, it is suitable for liquefaction assessment. Thus, the SDS method has great potential as an in-situ testing method for geotechnical site characterisation, especially for residential house construction. In this paper, the results of SDS tests performed at a variety of sites in New Zealand are presented. The soil database was employed to develop a soil classification chart based on SDS-derived parameters. Moreover, using the data obtained following the 2010-2011 Christchurch Earthquake Se-quence, a methodology was established for liquefaction potential evaluation using SDS data. http://www.isc5.com.au/wp-content/uploads/2016/09/1345-2-ORENSE.pdf
In the aftermath of the 2010-2011 Canterbury earthquakes in New Zealand, the residual capacity and reparability of damaged reinforced concrete (RC) structures was an issue pertinent to building owners, insurers, and structural engineers. Three precast RC moment-resisting frame specimens were extracted during the demolition of the Clarendon Tower in Christchurch after sustaining earthquake damage. These specimens were subjected to quasi-static cyclic testing as part of a research program to determine the reparability of the building. It was concluded that the precast RC frames were able to be repaired and retrofitted to an enhanced strength capacity with no observed reduction in displacement capacity, although the frames with “shear-ductile” detailing exhibited less displacement ductility capacity and energy dissipation capacity than the more conventionally detailed RC frames. Furthermore, the cyclic test results from the earthquake-damaged RC frames were used to verify the predicted inelastic demands applied to the specimens during the 2010-2011 Canterbury earthquakes. https://www.concrete.org/publications/acistructuraljournal.aspx
Following a damaging earthquake, the immediate emergency response is focused on individual collapsed buildings or other "hotspots" rather than the overall state of damage. This lack of attention to the global damage condition of the affected region can lead to the reporting of misinformation and generate confusion, causing difficulties when attempting to determine the level of postdisaster resources required. A pre-planned building damage survey based on the transect method is recommended as a simple tool to generate an estimate of the overall level of building damage in a city or region. A methodology for such a transect survey is suggested, and an example of a similar survey conducted in Christchurch, New Zealand, following the 22 February 2011 earthquake is presented. The transect was found to give suitably accurate estimates of building damage at a time when information was keenly sought by government authorities and the general public. VoR - Version of Record
Between September 4, 2010 and December 23, 2011, a series of earthquakes struck the South Island of New Zealand including the city of Christchurch producing heavy damage. During the strongest shaking, the unreinforced masonry (URM) building stock in Christchurch was subjected to seismic loading equal to approximately 150-200% of code values. Post-earthquake reconnaissance suggested numerous failures of adhesive anchors used for retrofit connection of roof and floor diaphragms to masonry walls. A team of researchers from the Universities of Auckland (NZ) and Minnesota (USA) conducted a field investigation on the performance of new adhesive anchors installed in existing masonry walls. Variables included adhesive type, anchor diameter, embedment length, anchor inclination, and masonry quality. Buildings were selected that had been slated for demolition but which featured exterior walls that had not been damaged. A summary of the deformation response measured during the field tests are presented. AM - Accepted Manuscript
This article is a critical commentary of how political documentary embodies the traits and functions of alternative journalism. I explore this notion through Obrero (‘worker’) my independent documentary project about the labour migration of Filipino workers to Christchurch, Aotearoa New Zealand, after the earthquake in 2011. This article maps out the points at where the theories and practices of alternative media and documentary intersect. Analysing political documentary as a format of alternative journalism has links to the long tradition of film and video production as a tool for social critique. As a form of practice-based research, Obrero falls under the rubric of alternative journalism—able to represent the politically marginal sectors of the polity and report on issues underreported in the mainstream press. This article concludes that a distribution plan that is responsive to fragmenting audiences works best when alternative journalism no longer targets a niche but transborder audiences.
This paper explores the responses by a group of children to an art project that was undertaken by a small school in New Zealand after the September 2010 and February 2011 Christchurch earthquakes. Undertaken over a period of two years, the project aimed to find a suitable form of memorialising this significant event in a way that was appropriate and meaningful to the community. Alongside images that related directly to the event of the earthquakes, the art form of a mosaic was chosen, and consisted of images and symbols that clearly drew on the hopes and dreams of a school community who were refusing to be defined by the disaster. The paper 'writes' the mosaic by placing fragments of speech spoken by the children involved in relation to ideas about memory, affect, and the 'sublime', through the work of Jean-Francois Lyotard. The paper explores the mosaic as constituted by the literal and metaphorical 'broken pieces' of the city of Christchurch in ways that confer pedagogic value inscribed through the creation of a public art space by children. AM - Accepted Manuscript
New Zealand's devastating Canterbury earthquakes provided an opportunity to examine the efficacy of existing regulations and policies relevant to seismic strengthening of vulnerable buildings. The mixed-methods approach adopted, comprising both qualitative and quantitative approaches, revealed that some of the provisions in these regulations pose as constraints to appropriate strengthening of earthquake-prone buildings. Those provisions include the current seismic design philosophy, lack of mandatory disclosure of seismic risks and ineffective timeframes for strengthening vulnerable buildings. Recommendations arising from these research findings and implications for pre-disaster mitigation for future earthquake and Canterbury's post-disaster reconstruction suggest: (1) a reappraisal of the requirements for earthquake engineering design and construction, (2) a review and realignment of all regulatory frameworks relevant to earthquake risk mitigation, and (3) the need to develop a national programme necessary to achieve consistent mitigation efforts across the country. These recommendations are important in order to present a robust framework where New Zealand communities such as Christchurch can gradually recover after a major earthquake disaster, while planning for pre-disaster mitigation against future earthquakes. AM - Accepted Manuscript
This section considers forms of collaboration in situated and community projects embedded in important spatial transformation processes in New Zealand cities. It aims to shed light on specific combinations of material and semantic aspects characterising the relation between people and their environment. Contributions focus on participative urban transformations. The essays that follow concentrate on the dynamics of territorial production of associations between multiple actors belonging both to civil society and constituted authority. Their authors were directly engaged in the processes that are reported and conceptualised, thereby offering evidence gained through direct hands-on experience. Some of the investigations use case studies that are conspicuous examples of the recent post-traumatic urban development stemming from the Canterbury earthquakes of 2010-2011. More precisely, these cases belong to the early phases of the programmes of the Christchurch recovery or the Wellington seismic prevention. The relevance of these experiences for the scope of this study lies in the unprecedented height of public engagement at local, national and international levels, a commitment reached also due to the high impact, both emotional and concrete, that affected the entire society.
This research is a creative exploration of transmedia’s ability to offer up a model of distribution and audience engagement for political documentary. Transmedia, as is well known, is a fluid concept. It is not restricted to the activities of the entertainment industry and its principles also reverberate in the practice of political and activist documentary projects. This practice-led research draws on data derived from the production and circulation of Obrero, an independent transmedia documentary. The project explores the conditions and context of the Filipino rebuild workers who migrated to Christchurch, New Zealand after the earthquake in 2011. Obrero began as a film festival documentary that co-exists with two other new media iterations, each reaching its respective target audience: a web documentary, and a Facebook-native documentary. This study argues that relocating the documentary across new media spaces not only expands the narrative but also extends the fieldwork and investigation, forms like-minded publics, and affords the creation of an organised hub of information for researchers, academics and the general public. Treating documentary as research can represent a novel pathway to knowledge generation and the present case study, overall, provides an innovative model for future scholarship.
The sequence of earthquakes that has affected Christchurch and Canterbury since September 2010 has caused damage to a great number of buildings of all construction types. Following post-event damage surveys performed between April 2011 and June 2011, an inventory of the stone masonry buildings in Christchurch and surrounding areas was carried out in order to assemble a database containing the characteristic features of the building stock, as a basis for studying the vulnerability factors that might have influenced the seismic performance of the stone masonry building stock during the Canterbury earthquake sequence. The damage suffered by unreinforced stone masonry buildings is reported and different types of observed failures are described using a specific survey procedure currently in use in Italy. The observed performance of seismic retrofit interventions applied to stone masonry buildings is also described, as an understanding of the seismic response of these interventions is of fundamental importance for assessing the utility of such strengthening techniques when applied to unreinforced stone masonry structures. AM - Accepted Manuscript
In 2013 Becca Wood, Spatial Performance Practitioner, and Molly Mullen, Applied Theatre Practitioner, collaborated to create a short ambulatory performance with audio score for a group of drama educators attending a conference workshop on the possibilities of walking as performance. The performance was created remotely from the intended site: Rangi Ruru Girls’ School, in Christchurch, New Zealand. Following the destruction of the 2012 earthquake, this site was in a state of transformation and recovery. The performance walk attended to the histories, geographies and politics of this place, somatically, architecturally and socially. This paper engages with three critical questions: How might mediated listening and walking activate the coming together of bodies and place? What performative shifts occurred for the participants in the walk and workshop? How might we come to our senses? Through a performative practice of mediated site-based listening and walking, this paper is a reflection on the creative process and performance. We consider the potential for technologically mediated performance to offer new modes for learning and creative practice through interdisciplinary and evolving intermedial practices. http://www.tandfonline.com/toc/crde20/current AM - Accepted Manuscript
A dramatic consequence of the Christchurch, New Zealand, earthquakes of 2010 and 2011 was the widespread liquefaction in the city. Part of the central business district (CBD) was badly affected by liquefaction but elsewhere large volumes of ejecta were not evident for those parts of the CBD where the upper layers in the soil profile are sandy gravel and gravelly sand. The purpose of the paper is to investigate the effect of the gravel permeability on the rise and dissipation of excess pore water pressure during cyclic loading of a soil profile idealised from Christchurch data. The Cyclic1D software, which performs one-dimensional non-linear effective stress site response analysis, was used. Permeability values associated with gravel were found to suppress the cyclic accumulation of excess pore water pressure in gravel layers. Given that there has not been any systematic measurement of the in situ permeability of the gravels in Christchurch, the modelling in the paper suggests that likely values for the bulk permeability of the gravel layers are within the range suggested in the geotechnical literature. However, the work reported is of wider application than Christchurch and emphasises the controlling influence of permeability on the accumulation and dissipation of cyclic pore pressures. VoR - Version of Record
The Manchester Courts building was a heritage building located in central Christchurch (New Zealand) that was damaged in the Mw 7.1 Darfield earthquake on 4 September 2010 and subsequently demolished as a risk reduction exercise. Because the building was heritage listed, the decision to demolish the building resulted in strong objections from heritage supporters who were of the opinion that the building had sufficient residual strength to survive possible aftershock earthquakes. On 22 February 2011 Christchurch was struck by a severe aftershock, leading to the question of whether building demolition had proven to be the correct risk reduction strategy. Finite element analysis was used to undertake a performance-based assessment, validating the accuracy of the model using the damage observed in the building before its collapse. In addition, soil-structure interaction was introduced into the research due to the comparatively low shear wave velocity of the soil. The demolition of a landmark heritage building was a tragedy that Christchurch will never recover from, but the decision was made considering safety, societal, economic and psychological aspects in order to protect the city and its citizens. The analytical results suggest that the Manchester Courts building would have collapsed during the 2011 Christchurch earthquake, and that the collapse of the building would have resulted in significant fatalities.
