Search

found 100 results

Images, Alexander Turnbull Library

Under the caption 'Best value for money?' is a football stadium displaying a red cross. From within a voice proclaims the advantages of having a combined covered stadium, hospital and blood bank. Under CERA, the Christchurch Central Development Unit had planned for a covered sports stadium, with attached facilities and shops as one of the key sites in the Christchurch rebuild after the 2010 and 2011 earthquakes. The 'blood bin' refers to the recent practice in rugby of sending off players with flesh wounds. There were also plans for a new hospital. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

The Canterbury earthquakes, which involved widespread damage in the February 2011 event and ongoing aftershocks near the Christchurch central business district (CBD), presented decision-makers with many recovery challenges. This paper identifies major government decisions, challenges, and lessons in the early recovery of Christchurch based on 23 key-informant interviews conducted 15 months after the February 2011 earthquake. It then focuses on one of the most important decisions – maintaining the cordon around the heavily damaged CBD – and investigates its impacts. The cordon displaced 50,000 central city jobs, raised questions about (and provided new opportunities for) the long-term viability of downtown, influenced the number and practice of building demolitions, and affected debris management; despite being associated with substantial losses, the cordon was commonly viewed as necessary, and provided some benefits in facilitating recovery. Management of the cordon poses important lessons for planning for catastrophic urban earthquakes around the world.

Other, National Library of New Zealand

An initiative developed by the Christchurch City Council in which the community can share their ideas on a new vision for the future development of the central city following the Canterbury earthquakes.

Research papers, University of Canterbury Library

This research attempts to understand how the Christchurch rebuild is promoting urban liveability in the Central City, focussing on the influence of communities and neighbourhoods in this area. To do this, gathering the perceptions of Christchurch residents through surveys, a focus group and semi-structured interviews was carried out to see what aspects they believe contribute to creating more liveable places. These methods revealed that there are pockets of neighbourhoods and communities in the inner-city, but no overall sense of community. Results from the semi-structured interviews reinforced this; the current buyers of inner-city property are in the financial position to be able to do this, and they seem to be purchasing in this area due to convenience and investment rather than to join the existing communities in the area. Analysing the survey responses from Central City residents revealed contrasting results. Those currently living in the area felt there is a sense of community in the inner-city, but these are found in pockets of neighbourhoods around the Central City rather than in the overall area. The focus group revealed that community is further prioritised later in life, and that many of the community groups in the inner-city predominantly consist of those who have lived there since before the Christchurch Earthquake Series. However, participants of all three methods believed that the Central City is slowly becoming a lively and vibrant place. To improve urban liveability in the inner-city, it seems that prioritisation of the needs of current inner-city residents is required. Improving these neighbourhoods, whether it be through the implementation of services or providing more communal spaces, is needed to create stronger communities. The feelings of place, connectedness, and belonging that arise from being part of a community or well-connected neighbourhood can improve mental health and wellbeing, ultimately enhancing the overall health of the population as well as the perceived urban liveability of the area.

Research papers, University of Canterbury Library

We examined changes in psychological distress experienced by residents of Christchurch following two catastrophic earthquakes in late 2010 and early 2011, using data from the New Zealand Attitudes and Values Study (NZAVS), a national probability panel study of New Zealand adults. Analyses focused on the 267 participants (172 women, 95 men) who were living in central Christchurch in 2009 (i.e., before the Christchurch earthquakes), and who also provided complete responses to our yearly panel questionnaire conducted in late 2010 (largely between the two major earthquakes), late 2011, and late 2012. Levels of psychological distress were similar across the different regions of central Christchurch immediately following the September 2010 earthquake, and remained comparable across regions in 2011. By late 2012, however, average levels of psychological distress in the regions had diverged as a function of the amount of property damage experienced within each given region. Specifically, participants in the least damaged region (i.e., the Fendalton-Waimairi and Riccarton-Wigram wards) experienced greater drops in psychological distress than did those in the moderately damaged region (i.e., across the Spreydon-Heathcote and Hagley- Ferrymead wards). However, the level of psychological distress reported by participants in the most damaged region (i.e., across Shirley-Papanui and Burwood-Pegasus) were not significantly different to those in the least damaged region of central Christchurch. These findings suggest that different patterns of psychological recovery emerged across the different regions of Christchurch, with the moderately damaged region faring the worst, but only after the initial shock of the destruction had passed.

Images, Alexander Turnbull Library

Three people stand looking down at a small model of the 'Christchurch CBD'. One of the people says 'Love the safer low-rise plan What's the scale?' A second man says 'Scale? Er this is the actual size!' Context: Christchurch Mayor Bob Parker has dedicated the draft plan for a new-look Christchurch CBD to those lost in the February earthquake. The CBD will be about a quarter of its original size under the draft plan which was unanimously adopted by the council today. (TVNZ 11 August 2011) Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

Text above reads 'Central Christchurch business owners protest' and the words 'Cordon Blur' (wordplay on famous cookery schools 'Cordon Bleu' and 'blur' as in 'unclear'). The cartoon shows a striped barrier bearing the words 'KEEP OUT' that is being torn to pieces. A second version continues the text to read 'Central Christchurch business owners protest as future directions unclear'. Context - Protests from angry Christchurch business owners locked out of the damaged CBD have intensified today, with police physically intervening when several protesters went inside the cordon. They are worried about the state of their businesses inside the red zone, and say they have not been allowed in to collect critical records and basic tools so they can carry on working outside the cordon. (NZ Herald 21 March 2011) Quantity: 2 digital cartoon(s).

Images, Alexander Turnbull Library

A rescue worker carries the dead body of a woman out of the crumbled remains of a building. Nearby is a copy of the 'Building Code'. Context - there are questions being asked about whether some of the buildings that collapsed too readily in the Christchurch earthquake of 22 February 2011 had been subject to stringent enough building code regulations. The Department of Building and Housing said the vertical shaking in the central business district was both extreme and unusual and early indications suggest it was much more violent than designed for in the building code standards which are based on the kind of shaking expected to happen every 500 years. Quantity: 1 digital cartoon(s).

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.

Images, Alexander Turnbull Library

Aspects of Christchurch life after the earthquakes of 2010 and 2011, modelled on acts performed at the Buskers' Festival being held in Christchurch. Include `Silt walking'through liquefaction; 'Orange zone', representing the paralysis of homeowners whose properties were classified as 'orange', or of undecided status; 'Jugglers "Marryatt" and "Red Zone"': the Christchurch CEO, Tony Marryatt, juggles with money, his large pay rise, while the red-zoned householder juggles with unattractive options; 'The boy [CBD] with red tape all over him', referring to the cordon which was strangling the Central Business District; the columnist Joe Bennett with his dog, refusing to move from his house in Lyttelton, a cause celebre of resistance to the earthquake authorities in those days. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

Depicts huge elderly woman with 'CERA' on her dress scolding smaller adult dressed as schoolboy near bustop with sign 'CBD red zone tours' Text reads 'And don't talk to strangers and don't cross the road and remember to eat your lunch..' Context: After the 22 Feburary 2011 earthquake in Christchurch, the central business district (CBD) was marked as a red zone. Red zone areas were deemed unsuitable for habitation due to significant damage and at high risk of further damage from low levels of earth shaking. CERA (Christchurch Earthquake Recovery Authority) ran public bus tours of the Christchurch CBD from November to December 2011. For safety reasons the public was not allowed off the buses as it was a dangerous and active demolition site. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

Novel Gel-push sampling was employed to obtain high quality samples of Christchurch sands from the Central Business District, at sites where liquefaction was observed in 22 February 2011, and 13 June 2011 earthquakes. The results of cyclic triaxial testing on selected undisturbed specimens of typical Christchurch sands are presented and compared to empirical procedures used by practitioners. This comparison suggests cyclic triaxial data may be conservative, and the Magnitude Scaling Factor used in empirical procedures may be unconservative for highly compressible soils during near source moderate to low magnitude events. Comparison to empirical triggering curves suggests the empirical method generally estimates the cyclic strength of Christchurch sands within a reasonable degree of accuracy as a screening evaluation tool for liquefaction hazard, however for sands with moderate to high fines content it may be significantly unconservative, highlighting the need for high quality sampling and testing on important projects where seismic performance is critical.

Research papers, University of Canterbury Library

In the period between September 2010 and December 2011, Christchurch (New Zealand) and its surroundings were hit by a series of strong earthquakes including six significant events, all generated by local faults in proximity to the city: 4 September 2010 (Mw=7.1), 22 February 2011 (Mw=6.2), 13 June 2011 (Mw=5.3 and Mw=6.0) and 23 December 2011 (M=5.8 and (M=5.9) earthquakes. As shown in Figure 1, the causative faults of the earthquakes were very close to or within the city boundaries thus generating very strong ground motions and causing tremendous damage throughout the city. Christchurch is shown as a lighter colour area, and its Central Business District (CBD) is marked with a white square area in the figure. Note that the sequence of earthquakes started to the west of the city and then propagated to the south, south-east and east of the city through a set of separate but apparently interacting faults. Because of their strength and proximity to the city, the earthquakes caused tremendous physical damage and impacts on the people, natural and built environments of Christchurch. The 22 February 2011 earthquake was particularly devastating. The ground motions generated by this earthquake were intense and in many parts of Christchurch substantially above the ground motions used to design the buildings in Christchurch. The earthquake caused 182 fatalities, collapse of two multi-storey reinforced concrete buildings, collapse or partial collapse of many unreinforced masonry structures including the historic Christchurch Cathedral. The Central Business District (CBD) of Christchurch, which is the central heart of the city just east of Hagley Park, was practically lost with majority of its 3,000 buildings being damaged beyond repair. Widespread liquefaction in the suburbs of Christchurch, as well as rock falls and slope/cliff instabilities in the Port Hills affected tens of thousands of residential buildings and properties, and shattered the lifelines and infrastructure over approximately one third of the city area. The total economic loss caused by the 2010-2011 Christchurch earthquakes is currently estimated to be in the range between 25 and 30 billion NZ dollars (or 15% to 18% of New Zealand’s GDP). After each major earthquake, comprehensive field investigations and inspections were conducted to document the liquefaction-induced land damage, lateral spreading displacements and their impacts on buildings and infrastructure. In addition, the ground motions produced by the earthquakes were recorded by approximately 15 strong motion stations within (close to) the city boundaries providing and impressive wealth of data, records and observations of the performance of ground and various types of structures during this unusual sequence of strong local earthquakes affecting a city. This paper discusses the liquefaction in residential areas and focuses on its impacts on dwellings (residential houses) and potable water system in the Christchurch suburbs. The ground conditions of Christchurch including the depositional history of soils, their composition, age and groundwater regime are first discussed. Detailed liquefaction maps illustrating the extent and severity of liquefaction across Christchurch triggered by the sequence of earthquakes including multiple episodes of severe re-liquefaction are next presented. Characteristic liquefaction-induced damage to residential houses is then described focussing on the performance of typical house foundations in areas affected by liquefaction. Liquefaction impacts on the potable water system of Christchurch is also briefly summarized including correlation between the damage to the system, liquefaction severity, and the performance of different pipe materials. Finally, the characteristics of Christchurch liquefaction and its impacts on built environment are discussed in relation to the liquefaction-induced damage in Japan during the 11 March 2011 Great East Japan Earthquake.

Research papers, University of Canterbury Library

Organisations locate strategically within Business Districts (CBDs) in order to cultivate their image, increase their profile, and improve access to customers, suppliers, and services. While CBDs offer an economic benefit to organisations, they also present a unique set of hazard vulnerabilities and planning challenges for businesses. As of May 2012, the Christchurch CBD has been partially cordoned off for over 14 months. Economic activity within the cordoned CBD, which previously contained 6,000 businesses and over 51,000 workers, has been significantly diminished and organisations have been forced to find new ways of operating. The vulnerabilities and resilience of CBDs not only influences outcomes for CBD organisations, but also the broader interconnected (urban/regional/national) system. A CBD is a hub of economic, social, and built infrastructure within a network of links and nodes. When the hub is disrupted all of the people, objects, and transactions that usually flow into and out of the hub must be redirected elsewhere. In an urban situation this means traffic jams in peripheries of the city, increased prices of commercial property, and capital flight; all of which are currently being faced in Canterbury. This report presents the lessons learned from organisations in CBDs affected by the Canterbury earthquakes. Here we focus on the Christchurch CBD; however, several urban town centres were extensively disrupted by the earthquakes. The statistics and discussion presented in this report are based on the results of an ongoing study conducted by Resilient Organisations (www.resorgs.org.nz). The data was captured using two questionnaire surveys of Canterbury organisations (issued November 2010 and May 2011), interviews with key informants, and in-depth case studies of organisations. Several industry sectors were sampled, and geographic samples of organisations in the Christchurch CBD, Lyttelton, and the Kaiapoi town centre were also collected. Results in this report describing “non-CBD organisations” refer to all organisations outside of the Christchurch CBD, Lyttelton, and Kaiapoi town centres.

Images, Alexander Turnbull Library

Shows Minister for Christchurch Earthquake Recovery Gerry Brownlee delighted with his plan to rebuild Christchurch and to have it paid for buy the PM's casino. Context: Refers to the Christchurch Central Development Unit that Minister for Christchurch Earthquake Recovery Gerry Brownlee has put in place. Refers also to the very controversial deal that Prime Minister John Key has made with Auckland's SkyCity to the effect that SkyCity will pay the full construction cost of a new convention centre - estimated at $350 million, in return for being allowed to add more gaming tables and machines, and extending its licence beyond 2021. Colour and black and white versions of this cartoon are available Quantity: 2 digital cartoon(s).

Research papers, University of Canterbury Library

Over 900 buildings in the Christchurch central business district and 10,000 residential homes were demolished following the 22nd of February 2011 Canterbury earthquake, significantly disrupting the rebuild progress. This study looks to quantify the time required for demolitions during this event which will be useful for future earthquake recovery planning. This was done using the Canterbury Earthquake Recovery Authority (CERA) demolition database, which allowed an in-depth look into the duration of each phase of the demolition process. The effect of building location, building height, and the stakeholder which initiated the demolition process (i.e. building owner or CERA) was investigated. The demolition process comprises of five phases; (i) decision making, (ii) procurement and planning, (iii) demolition, (iv) site clean-up, and (v) completion certification. It was found that the time required to decide to demolish the building made up majority of the total demolition duration. Demolition projects initiated by CERA had longer procurement and planning durations, but was quicker in other phases. Demolished buildings in the suburbs had a longer decision making duration, but had little effect on other phases of the demolition process. The decision making and procurement and planning phases of the demolition process were shorter for taller buildings, though the other phases took longer. Fragility functions for the duration of each phase in the demolition process are provided for the various categories of buildings for use in future studies.

Research papers, University of Canterbury Library

This paper presents insights from recent advanced laboratory testing of undisturbed and reconstituted specimens of Christchurch silty-sands. The purpose of the testing was to establish the cyclic strength of silty-sands from sites in the Central Business District (CBD), where liquefaction was observed in 4 September 2010, 22 February 2011, and 13 June 2011. Similar overall strengths were obtained from undisturbed and reconstituted tests prepared at similar densities, albeit with higher variability for the reconstituted specimens. Reconstituted specimens exhibited distinctly different response in terms of lower compressibility during initial loading cycles, and exhibited a more brittle response when large strains were mobilised, particularly for samples with high fines content. Given the lower variability in natural sample response and the possibility of age-related strength to be significant for sites not subjected to earthquakes, high quality undisturbed samples are recommended over the use of reconstituted specimens to establish the cyclic strength of natural sands.

Research papers, University of Canterbury Library

The city of Christchurch and its surrounds experienced widespread damage due to soil liquefaction induced by seismic shaking during the Canterbury earthquake sequence that began in September 2010 with the Mw7.1 Darfield earthquake. Prior to the start of this sequence, the city had a large network of strong motion stations (SMSs) installed, which were able to record a vast database of strong ground motions. This paper uses this database of strong ground motion recordings, observations of liquefaction manifestation at the ground surface, and data from a recently completed extensive geotechnical site investigation program at each SMS to assess a range of liquefaction evaluation procedures at the four SMSs in the Christchurch Central Business District (CBD). In general, the characteristics of the accelerograms recorded at each SMS correlated well with the liquefaction evaluation procedures, with low liquefaction factors of safety predicted at sites with clear liquefaction identifiers in the ground motions. However, at sites that likely liquefied at depth (as indicated by evaluation procedures and/or inferred from the characteristics of the recorded surface accelerograms), the presence of a non-liquefiable crust layer at many of the SMS locations prevented the manifestation of any surface effects. Because of this, there was not a good correlation between surface manifestation and two surface manifestation indices, the Liquefaction Potential Index (LPI) and the Liquefaction Severity Number (LSN).

Research papers, University of Canterbury Library

Local independent radio stations in Christchurch, New Zealand, had their operations severely disrupted by major earthquakes in September 2010 and February 2011. This article examines the experiences of three radio stations that were shut out of their central city premises by the cordon drawn around the city after the 22 February quake. One of the stations continued broadcasting automatically, while the others were unable to fully get back on air for several weeks afterwards. All of the stations had to manage access to workspaces, the emotional needs of staff and volunteers, the technical ability to broadcast, and the need to adapt content appropriately when back on air. For the locally based radio managers decisions had to be made about the future of the stations in a time of significant emotional, physical, and geological upheaval. The article explores how these radio stations were disrupted by the earthquake, and how they returned to air through new combinations and interconnections of people, workspace, technology, content and transmission.

Images, Alexander Turnbull Library

The title reads 'Satellite to plunge to earth "People should see quite a show." A 'NASA' satellite heads towards New Zealand; someone inside says 'Beep! Beep! Christchurch CBD here we come! Woo-hoo!' Context: A great deal of the CBD (Central Business District) in Christchurch is being demolished, considered to dangerous or too expensive to restore. A defunct 6.5 ton NASA satellite falls to earth this week... 26 pieces, with a combined mass of 500kg will survive the fiery re-entry and hurtle towards us. NASA doesn't have much idea of where it will land so it may demolish some of Christchurch. Quantity: 1 digital cartoon(s).

Images, Alexander Turnbull Library

Finance Minister Bill English holds a large axe that represents the 'budget' and says 'I wanted to retrieve all my spending tools, but, sadly, with allotted time short, I could only grab this!..' He is standing outside the barrier that surrounds the Christchurch CBD. Context - The Christchurch central business district has been largely out of bounds to anyone but those dealing with the after-effects of the earthquake of February 22 but business owners have been allowed restricted access to retrieve gear and belongings. The 2011 budget looks as though it will be focused on paring everything down because of the sad state of New Zealand's economy at present (made worse by the need to rebuild Christchurch), hence the axe. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

The 2010-2011 Canterbury Earthquakes brought devastation to the city of Christchurch and has irrevocably affected the lives of the city’s residents. Years after the conclusion of these earthquakes, Christchurch and its residents are well on the path to recovery. Crime has proven an ongoing topic of discussion throughout this period, with news reports of increased burglary and arson in areas left largely abandoned by earthquake damage, and a rise in violent crime in suburban areas of Christchurch. Following the body of research that has considered the reaction of crime to natural disasters, this research has sought to comprehensively examine and understand the effects that the Canterbury Earthquakes had on crime. Examining Christchurch-wide offending, crime rates fell over the study period (July 2008 to June 2013), with the exception of domestic violence. Aside from a momentary increase in burglary in the days immediately following the Christchurch Earthquake, crime rates (as of 2013) have remained largely below pre-earthquake levels. Using Dual Kernel Density Estimation Analysis, a distinct spatial change in pre-earthquake crime hotspots was observed. These changes included an enormous decrease in central city offences, a rise in burglary in the eastern suburbs, and an increase in assault in areas outside of the central city. Logistic regression analysis, using a time-compensated dependent variable, identified a number of statistically-significant relationships between per CAU crime rate change and factors measuring socio-demographic characteristics, community cohesion, and the severity of disaster effects. The significance of these findings was discussed using elements of Social Disorganisation Theory, Routine Activity Theory, and Strain Theory. Consistent with past findings, social order was largely maintained following the Canterbury Earthquakes, with suggestion that increased collective efficacy and therapeutic communities had a negative influence on crime in the post-earthquake period. Areas of increased burglary and assault were associated with large population decreases, suggesting a link with the dissolution of communities and the removal of their inherent informal guardianship. Though observed, the increase in domestic violence was not associated with most neighbourhood-level variables. Trends in crime after the Canterbury Earthquakes were largely consistent with past research, and the media’s portrayal.

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 thesis considers the presence and potential readings of graffiti and street art as part of the wider creative public landscape of Christchurch in the wake of the series of earthquakes that significantly disrupted the city physically and socially. While documenting a specific and unprecedented period of time in the city’s history, the prominence of graffiti and street art throughout the constantly changing landscape has also highlighted their popularity as increasingly entrenched additions to urban and suburban settings across the globe. In post-quake Christchurch, graffiti and street art have often displayed established tactics, techniques and styles while exploring and exposing the unique issues confronting this disrupted environment, illustrating both a transposable nature and the entwined relationship with the surrounding landscape evident in the conception of these art forms. The post-quake city has afforded graffiti and street art the opportunity to engage with a range of concepts: from the re-activation and re-population of the empty and abandoned spaces of the city, to commentaries on specific social and political issues, both angry and humorous, and notably the reconsideration of entrenched and evolving traditions, including the distinction between guerrilla and sanctioned work. The examples of graffiti and street art within this work range from the more immediate post-quake appearance of art in a group of affected suburbs, including the increasingly empty residential red-zone, to the use of the undefined spaces sweeping the central city, and even inside the Canterbury Museum, which housed the significant street art exhibition Rise in 2013-2014. These settings expose a number of themes, both distinctive and shared, that relate to both the post-disaster landscape and the concerns of graffiti and street art as art movements unavoidably entangled with public space.

Research papers, The University of Auckland Library

The 2011, 6.3 magnitude Christchurch earthquake in New Zealand caused considerable structural damage. It is believed that this event has now resulted in demolition of about 65-70% of the building stock in the Central Business District (CBD), significantly crippling economic activities in the city of Christchurch. A major concern raised from this event was adequacy of the current seismic design practice adopted for reinforced concrete walls due to their poor performance in modern buildings. The relatively short-duration earthquake motion implied that the observed wall damage occurred in a brittle manner despite adopting a ductile design philosophy. This paper presents the lessons learned from the observed wall damage in the context of current state of knowledge in the following areas: concentrating longitudinal reinforcement in wall end regions; determining wall thickness to prevent out-of-plane wall buckling; avoiding lap splices in plastic hinge zones; and quantifying minimum vertical reinforcement. http://www.2eceesistanbul.org/

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.