
A complaint against an engineer whose firm designed the CTV building that collapsed in the Christchurch earthquake will be heard by a disciplinary committee on Monday. One-hundred-and-fifteen people were killed when the six-storey building came down in February 2011. Dr Alan Reay lost a High Court bid to stop the hearing. Reporter Anna Sargent spoke to Corin Dann.
Following the 2010-2011 Canterbury (New Zealand) earthquake sequence, lightly reinforced wall structures in the Christchurch central business district were observed to form undesirable crack patterns in the plastic hinge region, while yield penetration either side of cracks and into development zones was less than predicted using empirical expressions. To some extent this structural behaviour was unexpected and has therefore demonstrated that there may be less confidence in the seismic performance of conventionally designed reinforced concrete (RC) structures than previously anticipated. This paper provides an observation-based comparison between the behaviour of RC structural components in laboratory testing and the unexpected structural behaviour of some case study buildings in Christchurch that formed concentrated inelastic deformations. The unexpected behaviour and poor overall seismic performance of ‘real’ buildings (compared to the behaviour of laboratory test specimens) was due to the localization of peak inelastic strains, which in some cases has arguably led to: (i) significantly less ductility capacity; (ii) less hysteretic energy dissipation; and (iii) the fracture of the longitudinal reinforcement. These observations have raised concerns about whether lightly reinforced wall structures can satisfy the performance objective of “Life Safety” at the Ultimate Limit State. The significance of these issues and potential consequences has prompted a review of potential problems with the testing conditions and procedures that are commonly used in seismic experimentations on RC structures. This paper attempts to revisit the principles of RC mechanics, in particular, the influence of loading history, concrete tensile strength, and the quantity of longitudinal reinforcement on the performance of real RC structures. Consideration of these issues in future research on the seismic performance of RC might improve the current confidence levels in newly designed conventional RC structures.
The influence of nonlinear soil-foundation-structure interaction (SFSI) on the performance of multi-storey buildings during earthquake events has become increasingly important in earthquake resistant design. For buildings on shallow foundations, SFSI refers to nonlinear geometric effects associated with uplift of the foundation from the supporting soil as well as nonlinear soil deformation effects. These effects can potentially be beneficial for structural performance, reducing forces transmitted from ground shaking to the structure. However, there is also the potential consequence of residual settlement and rotation of the foundation. This Thesis investigates the influence of SFSI in the performance of multi-storey buildings on shallow foundations through earthquake observations, experimental testing, and development of spring-bed numerical models that can be incorporated into integrated earthquake resistant design procedures. Observations were made following the 22 February 2011 Christchurch Earthquake in New Zealand of a number of multi-storey buildings on shallow foundations that performed satisfactorily. This was predominantly the case in areas where shallow foundations, typically large raft foundations, were founded on competent gravel and where there was no significant manifestation of liquefaction at the ground surface. The properties of these buildings and the soils they are founded on directed experimental work that was conducted to investigate the mechanisms by which SFSI may have influenced the behaviour of these types of structure-foundation systems. Centrifuge experiments were undertaken at the University of Dundee, Scotland using a range of structure-foundation models and a layer of dense cohesionless soil to simulate the situation in Christchurch where multi-storey buildings on shallow foundations performed well. Three equivalent single degree of freedom (SDOF) models representing 3, 5, and 7 storey buildings with identical large raft foundations were subjected to a range of dynamic Ricker wavelet excitations and Christchurch Earthquake records to investigate the influence of SFSI on the response of the equivalent buildings. The experimental results show that nonlinear SFSI has a significant influence on structural response and overall foundation deformations, even though the large raft foundations on competent soil meant that there was a significant reserve of bearing capacity available and nonlinear deformations may have been considered to have had minimal effect. Uplift of the foundation from the supporting soil was observed across a wide range of input motion amplitudes and was particularly significant as the amplitude of motion increased. Permanent soil deformation represented by foundation settlement and residual rotation was also observed but mainly for the larger input motions. However, the absolute extent of uplift and permanent soil deformation was very small compared to the size of the foundation meaning the serviceability of the building would still likely be maintained during large earthquake events. Even so, the small extent of SFSI resulted in attenuation of the response of the structure as the equivalent period of vibration was lengthened and the equivalent damping in the system increased. The experimental work undertaken was used to validate and enhance numerical modelling techniques that are simple yet sophisticated and promote interaction between geotechnical and structural specialists involved in the design of multi-storey buildings. Spring-bed modelling techniques were utilised as they provide a balance between ease of use, and thus ease of interaction with structural specialists who have these techniques readily available in practice, and theoretically rigorous solutions. Fixed base and elastic spring-bed models showed they were unable to capture the behaviour of the structure-foundation models tested in the centrifuge experiments. SFSI spring-bed models were able to more accurately capture the behaviour but recommendations were proposed for the parameters used to define the springs so that the numerical models closely matched experimental results. From the spring-bed modelling and results of centrifuge experiments, an equivalent linear design procedure was proposed along with a procedure and recommendations for the implementation of nonlinear SFSI spring-bed models in practice. The combination of earthquake observations, experimental testing, and simplified numerical analysis has shown how SFSI is influential in the earthquake performance of multi-storey buildings on shallow foundations and should be incorporated into earthquake resistant design of these structures.
It is well known that buildings constructed using unreinforced masonry (URM) are susceptible to damage from earthquake induced lateral forces that may result in partial or full building collapse. The 2010/2011 Canterbury earthquakes are the most recent New Zealand example of destructive earthquakes, which have drawn people's attention to the inherent seismic weaknesses of URM buildings and anchored masonry veneer systems in New Zealand. A brief review of the data collected following the 2010 Darfield earthquake and more comprehensive documentation of data that was collected following the 2011 Christchurch earthquake is presented, along with the findings from subsequent data interrogation. Large stocks of earthquake prone vintage URM buildings that remain in New Zealand and in other seismically active parts of the world result in the need for minimally invasive and cost effective seismic retrofit techniques. The principal objective of the doctoral research reported herein was to investigate the applicability of near surface mounted (NSM) carbon fibre reinforced polymer (CFRP) strips as a seismic improvement technique. A comprehensive experimental program consisting of 53 pull tests is presented and is used to assess the accuracy of existing FRP-to-masonry bond models, with a modified model being proposed. The strength characteristics of vintage clay brick URM wall panels from two existing URM buildings was established and used as a benchmark when manufacturing replica clay brick test assemblages. The applicability of using NSM CFRP strips as a retrofitting technique for improving the shear strength and the ductility capacity of multi-leaf URM walls constructed using solid clay brick masonry is investigated by varying CFRP reinforcement ratios. Lastly, an experimental program was undertaken to validate the proposed design methodology for improving the strength capacity of URM walls. The program involved testing full-scale walls in a laboratory setting and testing full-scale walls in-situ in existing vintage URM buildings. Experimental test results illustrated that the NSM CFRP technique is an effective method to seismically strengthen URM buildings.
Shows a couple in their car driving along a road festooned with election billboards. The man reads a billboard and comments that the mayor is promising to 'move our district forward' and his partner suggests that with all the new jobs down in Christchurch maybe he should move the district down there. Probably refers to mayoral hopefuls in Whangarei, Pamela Sue Peters or Stan Semenoff, suggesting that people should move to Christchurch for jobs which, since the 4th September 2010 earthquake, are going to be plentiful. But it seems that every mayoral candidate in the country is intent on moving his or her part of New Zealand forward if they win the October 9 local body election. Quantity: 1 digital cartoon(s).
Four cartoons in the same frame commenting on news and happenings in the week ending 15 December 2011. The cartoons refer to the expulsion of the controversial Member of Parliament, Brendan Horan, from the New Zealand First Party by its leader, Winston Peters; the stereotyping of New Zealand as being 'Middle Earth' following the filming of 'The Hobbit', punned as 'The Habbit'; the lax attitude to building design and standards, which led to the CTV Building disaster in the Christchurch earthquake; the news about the New Zealand SPCA teaching dogs to drive. Quantity: 1 digital cartoon(s).
Nel presente articolo si illustra una procedura per il processamento automatizzato di prove CPT, il calcolo di vari indici di liquefazione e la rappresentazione dei dati su mappa. La procedura è applicata al caso studio del terremoto di Christchurch, Nuova Zelanda, del 22 febbraio 2011 (magnitudo momento, Mw = 6.2). Dall’analisi spaziale dei risultati emerge una buona correlazione tra le mappe ottenute per l’indicatore degli effetti al suolo e i danni osservati (su terreni e strutture). Tuttavia, per confermare la validità di tale procedura, sarà necessario esaminare ulteriori casi studio nel mondo.
A pdf copy of panel 1 of Guy Frederick's 'The Space Between Words' exhibition. The panel includes text from an interview with Meredith Dyer about her experiences of the 22 February 2011 earthquake. Above this is an image of Dyer sitting on a path in the Botanical Gardens.
A photograph of the earthquake damage to the Cathedral of the Blessed Sacrament on Barbadoes Street. The tower on the right has crumbled, and the masonry has fallen to the pavement below. A car has been crushed by the fallen rubble. Windows in the tower behind are broken.
The David and Goliath battle over a heritage building sitting in the way of a planned $473 million dollar, multi-use arena for Christchurch has ended up in court. The 25,000-seated, roofed arena is the final anchor project for the Christchurch rebuild and will be designed to host everything from All Blacks tests to big concerts. But sitting on the edge of the site, at 212 Madras Street, is the NG Building, a 115-year old warehouse that's home to a number of creative businesses. It escaped the worst of the 2011 earthquake and was strengthened by its owners: Roland Logan and Sharon Ng. They say they were told in 2013 the building could be incorporated into the arena's design, and are at loggerheads over its compulsory acquisition. Last week they were at the High Court seeking an injunction that would allow them to temporarily maintain ownership of the building, and that decision was released yesterday - and upheld. Roland joins Kathryn to discuss why they hope the building can be saved.
Existing New Zealand (NZ) building stock contains a significant number of structures designed prior to 1995 with non-ductile reinforced concrete (RC) columns. Recent earthquakes and research show that columns with such details perform poorly when subjected to seismic demand, losing gravity load carrying capacity at drift levels lower than the expected one. Therefore, in order to have a better understanding of existing RC columns in NZ, the history of these elements is investigated in this paper. The evolution of RC column design guidelines in NZ standards since the 1970s is scrutinized. For this purpose, a number of RC columns from Christchurch buildings built prior to 1995 are assessed using the current code of practice.
A video showing members of the SPCA standing for two minutes in silence a week after the 22 February 2011 earthquake, in memory of those who lost their lives. A pigeon, found in the ChristChurch Cathedral after the quakes, is released at the end of the two-minutes' silence.
A digitally manipulated image of the high diving boards at QEII swimming pool. Rubble has fallen on the boards during the demolition of the complex. The photographer comments, "The diving board at the QEII stadium swimming pool during its demolition after being damaged in the Christchurch earthquake in February 2011".
A press release from the United States Embassy New Zealand about the US-NZ Partnership Forum which was interrupted by the 22 February 2011 earthquake in Christchurch. Two months later, delegates from both New Zealand and the United States met in a video conference session designed to conclude the forum.
A brick wall has fallen from this house, exposing the rooms within and leaving a pile of rubble in front. The ceiling has slumped and is held up with jacks. The photographer comments, "This was probably the result of the shallower February Christchurch earthquake rather than the bigger September one".
A photograph of a group of tents set up in Latimer Square next to the Singapore Rescue Team's store and equipment area. Plastic mesh and tape has been placed around the tents as a fence. The tents were used as temporary accommodation for emergency management personnel after the 22 February 2011 earthquake.
A digitally manipulated image of the high diving boards at QEII swimming pool. Rubble has fallen on the boards during the demolition of the complex. A sign reads "Poseidon Extreme". The photographer comments, "I do not know what Poseidon Extreme at this swimming pool looked like before the earthquake damaged it, but it looks really radical now during it's demolition. A strange coincidence is that Poseidon is referred to as 'Earth-Shaker' due to his role in causing earthquakes. So the demolition of this pool due to the series of quakes in Christchurch all seems to be foretold by the gods and that sign".
Aerial footage of Christchurch after the 4 September 2010 earthquake. The footage shows the earthquake damage to Wizard Home Loans & Cartridge World on Riccarton Road, Harding's Chemist and Angus Donaldson Copy Service on Colombo Street, Para Rubber and Westende Jewellers on Manchester Street, The Loaded Hog on Cashel Street, St Mary & St Athanasios Church on Edgeware Road, The Daily Bagel on Victoria Street, the Laxmi Foodstore on Barbadoes Street, Television Services on Westminster Street, The Hat Shop on High Street, St Paul's Parish Church on Gayhurst Road, Sullivan Park on Galbraith Road, and Avonside Drive.
A preliminary case study assessing the seismic sustainability of two reinforced concrete structures, a frame structure and a wall structure, was conducted to determine which structural system is more seismically sustainable. The two structures were designed to the same standards and were assumed to be located in Christchurch, New Zealand. A component-based probabilistic seismic loss assessment, considering direct losses only, was conducted for two ground motion records, regarded to approximately represent a 1 in 500 year earthquake event and a 1 in 2500 year earthquake event, respectively. It is shown that the wall structure results in lower direct losses than the frame structure in the less severe ground motion scenario. However, in the more severe ground motion scenario, the frame structure results in lower direct losses. Hence, this study demonstrates that which structural system has the lower direct losses depends on the ground motion intensity level.
A compilation video of footage about the 4 September 2010 earthquake. The video includes footage of the damage to the central city, members of the police guarding cordons, residents at a Civil Defence Emergency Centre, a fire on Worcester Street, and aerial footage of New Brighton, the central city, and Homebush. It also includes an interview with local resident Quentin Garlick, and a press conference with Mayor Bob Parker outside the Christchurch Art Gallery.
A member of the Los Angeles County Fire Department Search and Rescue Team looking at the maps at the entrance to 'Camp Hollywood', the headquarters of the American Civil Defence Forces in Latimer Square. After the 22 February 2011 earthquake, emergency service agencies set up their headquarters in Latimer Square.
A member of the Los Angeles County Fire Department Search and Rescue Team looking at the maps at the entrance to 'Camp Hollywood', the headquarters of the American Civil Defence Forces in Latimer Square. After the 22 February 2011 earthquake, emergency service agencies set up their headquarters in Latimer Square.
A member of the Los Angeles County Fire Department Search and Rescue Team with an Australian Police Officer at the entrance to 'Camp Hollywood', the headquarters of the American Civil Defence Forces in Latimer Square. After the 22 February 2011 earthquake, emergency service agencies set up their headquarters in Latimer Square.
A photograph of the earthquake-damaged Cathedral of the Blessed Sacrament on Barbadoes Street. Rubble from the collapsed tower is lying on the ground in front. A car has been crushed under this rubble. Wire fencing, shipping containers, and road cones have been placed around the building as a cordon.
A photograph of the earthquake-damaged Cathedral of the Blessed Sacrament on Barbadoes Street. Rubble from the collapsed tower is lying on the ground in front. A car has been crushed under this rubble. Wire fencing, shipping containers, and road cones have been placed around the building as a cordon.
A photograph of the earthquake-damaged Cathedral of the Blessed Sacrament on Barbadoes Street. Rubble from the collapsed tower is lying on the ground in front. A car has been crushed under this rubble. Wire fencing, shipping containers, and road cones have been placed around the building as a cordon.
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.
This article discusses the use of radio after major earthquakes in Christchurch, New Zealand, in 2010 and 2011. It draws on archival sources to retrospectively research post-quake audiences in the terms people used during and soon after the earthquakes through personal narratives and Twitter. Retrospective narratives of earthquake experiences affirm the value of radio for communicating the scale of disaster and comforting listeners during dislocation from safe home spaces. In the narratives radio is often compared with television, which signifies electricity supply and associated comfort but also visually confirms the city’s destruction. Twitter provides insights into radio use from within the disaster period, but its more global reach facilitates reflection on online and international radio from outside the disaster-affected area. This research demonstrates the value of archival audience research, and finds that the combination of online radio and Twitter enables a new form of participatory disaster spectatorship from afar.
Initial recovery focus is on road access (especially the inland SH70) although attention also needs to be focussed on the timelines for reopening SH1 to the south. Information on progress and projected timelines is updated daily via NZTA (www.nzta.govt.nz/eq-travel ). Network analyses indicate potential day trip access and re-establishment of the Alpine Pacific triangle route. When verified against ‘capacity to host’ (Part 2 (15th December) there appears to potential for the reestablishment of overnight visits. Establishing secure road access is the key constraint to recovery. In terms of the economic recovery the Kaikoura District has traditionallyattracted a large number of visitors which can be grouped as: second home (and caravan) owners, domestic New Zealand and international travellers. These have been seen through a behaviour lens as “short stop”, ‘day” (where Kaikoura is the specific focal destination) and overnight visitors. At the present restricted access appears to make the latter group less amenable to visiting Kaikoura, not the least because the two large marine mammal operators have a strong focus on international visitors. For the present the domestic market provides a greater initial pathway to recovery. Our experiences in and reflections on Christchurch suggest Kaikoura will not go back to what it once was. A unique opportunity exists to reframe the Kaikoura experience around earthquake geology and its effects on human and natural elements. To capitalise on this opportunity there appears to be a need to move quickly on programming and presenting such experiences as part of a pathway to re-enabling domestic tourists while international visitor bookings and flows can be re-established. The framework developed for this study appears to be robust for rapid post disaster assessment. It needs to be regularly updated and linked with emerging governance and recovery processes.
Damage to Christchurch city following the 22 February earthquake 2011. A collapsed building on the corner of Ferry Road and Lancaster Street. The brick walls of the building have crumbled, bringing the roof down with them. The wall of the building opposite has been exposed, and there is now a doorway to nowhere.