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Images, Alexander Turnbull Library

Shows a happy crowd playing in the sea and sand in the Christchurch Square. Bishop Victoria Matthews is seen balancing on the Wizard of Christchurch who has turned himself into a surfboard. Context: refers to a proposal by Bishop of Christchurch Victoria Matthews that the earthquake-damaged Square could be made "welcoming and engaging" again by transforming it into an artificial beach with large movie screens. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

Between 2010 and 2011, Canterbury experienced a series of four large earthquake events with associated aftershocks which caused widespread damage to residential and commercial infrastructure. Fine grained and uncompacted alluvial soils, typical to the Canterbury outwash plains, were exposed to high peak ground acceleration (PGA) during these events. This rapid increase in PGA induced cyclic strain softening and liquefaction in the saturated, near surface alluvial soils. Extensive research into understanding the response of soils in Canterbury to dynamic loading has since occurred. The Earthquake Commission (EQC), the Ministry of Business and Employment (MBIE), and the Christchurch City Council (CCC) have quantified the potential hazards associated with future seismic events. Theses bodies have tested numerous ground improvement design methods, and subsequently are at the forefront of the Canterbury recovery and rebuild process. Deep Soil Mixing (DSM) has been proven as a viable ground improvement foundation method used to enhance in situ soils by increasing stiffness and positively altering in situ soil characteristics. However, current industry practice for confirming the effectiveness of the DSM method involves specific laboratory and absolute soil test methods associated with the mixed column element itself. Currently, the response of the soil around the columns to DSM installation is poorly understood. This research aims to understand and quantify the effects of DSM columns on near surface alluvial soils between the DSM columns though the implementation of standardised empirical soil test methods. These soil strength properties and ground improvement changes have been investigated using shear wave velocity (Vs), soil behaviour and density response methods. The results of the three different empirical tests indicated a consistent improvement within the ground around the DSM columns in sandier soils. By contrast, cohesive silty soils portrayed less of a consistent response to DSM, although still recorded increases. Generally, within the tests completed 50 mm from the column edge, the soil response indicated a deterioration to DSM. This is likely to be a result of the destruction of the soil fabric as the stress and strain of DSM is applied to the un‐mixed in situ soils. The results suggest that during the installation of DSM columns, a positive ground effect occurs in a similar way to other methods of ground improvement. However, further research, including additional testing following this empirical method, laboratory testing and finite 2D and 3D modelling, would be useful to quantify, in detail, how in situ soils respond and how practitioners should consider these test results in their designs. This thesis begins to evaluate how alluvial soils tend to respond to DSM. Conducting more testing on the research site, on other sites in Christchurch, and around the world, would provide a more complete data set to confirm the results of this research and enable further evaluation. Completing this additional research could help geotechnical DSM practitioners to use standardised empirical test methods to measure and confirm ground improvement rather than using existing test methods in future DSM projects. Further, demonstrating the effectiveness of empirical test methods in a DSM context is likely to enable more cost effective and efficient testing of DSM columns in future geotechnical projects.

Images, eqnz.chch.2010

The sign reads: The CTV Building was headquarters of Canterbury Television (CTV) and also housed King’s Education language School, a medical clinic, Hair Consultants, Relationship Services and a nursing school. On February 22nd 2011 the building collapsed as a result of a major earthquake. Sadly, 115 people who were in the building lost their l...

Research papers, University of Canterbury Library

The paper discusses modelling of cyclic stress-strain behaviour of soil, in particular a simple model that can produce a desired stiffness and hysteretic damping for a given strain level as observed in laboratory testing is formulated. The unloading-reloading relationship is developed for total stress seismic site response analysis with appropriate damping at large strain. The constitutive model employs a hyperbolic equation as the backbone curve, and uses a modification of the extended Masing unloading-reloading relationship leading to correct measured modulus reduction and damping curves simultaneously. A quasi-static cyclic loading of increasing amplitude is used to demonstrate the model’s performance and its capability to allow improved modelling of the magnitude of energy dissipation based on an experimental program on native sandy soils from Christchurch, New Zealand.

Research papers, University of Canterbury Library

This report presents an overview of the soil profile characteristics at a number of strong motion station (SMS) sites in Christchurch and its surrounds. An extensive database of ground motion records has been captured by the SMS network in the Canterbury region during the Canterbury earthquake sequence. However in order to comprehensively understand the ground motions recorded at these sites and to be able to relate these motions to other locations, a detailed understanding of the shallow geotechnical profile at each SMS is required. The original NZS1170.5 (SNZ 2004) site subsoil classifications for each SMS site is based on regional geological information and well logs located at varying distances from the site. Given the variability of Christchurch soils, more detailed investigations are required in close vicinity to each SMS to better understand stratigraphy and soil properties, which are important in seismic site response. In this regard, CPT, SPT and borehole data, shear wave velocity (Vs) profiles, and horizontal to vertical spectral ratio measurements (H/V) in close vicinity to the SMS were used to develop representative soil profiles at each site. NZS1170.5 (SNZ 2004) site subsoil classifications were updated using Vs and SPT N60 criteria. Site class E boundaries were treated as a sliding scale rather than as a discrete boundary to account for locations with similar site effects potential, an approach which was shown to result in a better delineation between the site classes. SPT N60 values often indicate a stiffer site class than the Vs data for softer soil sites, highlighting the disparity between the two site investigation techniques. Both SPT N60 and Vs based site classes did not always agree with the original site classifications. This emphasises the importance of having detailed site‐specific information at SMS locations in order to properly classify them. Furthermore, additional studies are required to harmonize site classification based on SPT N60 and Vs. Liquefaction triggering assessments were carried out for the Darfield and Christchurch earthquakes, and compared against observed liquefaction surface manifestations and ground motions characteristics at each SMS. In general, the characteristics of the recorded ground motions at each site correlate well with the triggering analyses. However, at sites that likely liquefied at depth (as indicated by triggering analyses and/or inferred from the characteristics of the recorded surface acceleration time series), the presence of a non‐liquefiable crust layer at many of the SMS locations prevented the manifestation of any surface effects.

Research papers, University of Canterbury Library

The 2010-2011 Canterbury earthquakes were recorded over a dense strong motion network in the near-source region, yielding significant observational evidence of seismic complexities, and a basis for interpretation of multi-disciplinary datasets and induced damage to the natural and built environment. This paper provides an overview of observed strong motions from these events and retrospective comparisons with both empirical and physics-based ground motion models. Both empirical and physics-based methods provide good predictions of observations at short vibration periods in an average sense. However, observed ground motion amplitudes at specific locations, such as Heathcote Valley, are seen to systematically depart from ‘average’ empirical predictions as a result of near surface stratigraphic and topographic features which are well modelled via sitespecific response analyses. Significant insight into the long period bias in empirical predictions is obtained from the use of hybrid broadband ground motion simulation. The comparison of both empirical and physics-based simulations against a set of 10 events in the sequence clearly illustrates the potential for simulations to improve ground motion and site response prediction, both at present, and further in the future.

Research papers, University of Canterbury Library

This study uses 44 high quality liquefaction case histories taken from 22 locations affected by the 2010-2011 Canterbury earthquake sequence to evaluate four commonly used CPT-VS correlations (i.e., Robertson, 2009; Hegazy and Mayne, 2006; Andrus et al., 2007; McGann et al., 2015b). Co-located CPT soundings and VS profiles, developed from surface wave testing, were obtained at 22 locations and case histories were developed for the Mw 7.1, 4 September 2010 Darfield and Mw 6.2, 22 February 2011 Christchurch earthquakes. The CPT soundings are used to generate VS profiles using each of four CPT-VS correlations. These correlated VS profiles are used to estimate the factor of safety against liquefaction using the Kayen et al. (2013) VS-based simplified liquefaction evaluation procedure. An error index is used to quantify the predictive capabilities of these correlations in relation to the observations of liquefaction (or the lack thereof). Additionally, the error indices from the CPT-correlated VS profiles are compared to those obtained using: (1) the Kayen et al. (2013) procedure with surface wave-derived VS profiles, and (2) the Idriss and Boulanger (2008) CPT-based liquefaction evaluation procedure. Based on the error indices, the evaluation procedures based on direct measurements of either CPT or VS provided more accurate liquefaction triggering estimates than those obtained from any of the CPT-VS correlations. However, the performance of the CPT-VS correlations varied, with the Robertson (2009) and Hegazy and Mayne (2006) correlations performing relatively poorly for the Christchurch soils and the Andrus et al. (2007) and McGann et al. (2015b) correlations performing better. The McGann et al. (2015b) correlation had the lowest error indices of the CPT-VS correlations tested, however, none of the CPT-VS correlations provided accurate enough VS predictions to be used for the evaluation of liquefaction triggering using the VS-based liquefaction evaluation procedures.

Research papers, University of Canterbury Library

La pericolosità associata ad un dato fenomeno costituisce uno dei fattori più importanti e difficili da quantificare nelle analisi di rischio, a maggior ragione quando si tratta di fenomeni complessi come nel caso della liquefazione sismica. Il presente lavoro illustra sinteticamente uno studio della pericolosità indotta al suolo da liquefazione basato su un caso campione statistico particolarmente significativo, il terremoto (Mw 6.2) che ha colpito Christchurch, Nuova Zelanda, del 2011. La notevole mole di dati disponibili, relativi alle caratteristiche geotecniche del sottosuolo, unitamente al rilievo dei danni ha consentito innanzitutto di caratterizzare la suscettibilità a liquefazione dell’area, indipendentemente dall’evento sismico, quindi di correlare statisticamente le diverse grandezze e di derivare delle curve di vulnerabilità del suolo.

Images, UC QuakeStudies

The Taiwanese Search and Rescue team (USAR) being farewelled at the Christchurch International Airport after helping out with the emergency response to the Canterbury Earthquake. In the centre is Rob Saunders from the New Zealand Fire Department, and on the right is Kao Wei, Team Leader of the Taiwan USAR team.

Images, UC QuakeStudies

Prime Minister John Key talking to members of the USAID Disaster Assistance Response Team (DART) outside the US headquarters in Latimer Square. John Key is visiting to thank DART for their efforts in the aftermath of the 22 February 2011 earthquake. Canterbury Recovery Minister Gerry Brownlee is standing behind him.

Images, UC QuakeStudies

A photograph of three petrol pumps at a BP station. One of the pumps has been covered by a piece of paper with a sticker reading, "out". Underneath the sticker, the paper reads, "Available - diesel only. Due to high demand (following the Canterbury Earthquake) we are currently out of petrol".

Images, Alexander Turnbull Library

It is the middle of the night and a man wearing his dressing-gown runs out of his house towards a portaloo clutching a toilet roll and saying 'Try me'. The neighbourhood is wrecked by earthquakes. On the ground is a newspaper with a headline that reads 'New Delhi athletes substandard accomodation facilities'. A second newspaper reads 'Given the choice many prefer to stay home'. Context: The first Christchurch earthquake shook the city on early morning of the 4th September 2010. The destruction of sewage infrastructure has meant portaloos and long-drops have become de rigeur as a consequence. There was a desperate rush to get the village ready for the influx of athletes before the opening of the Commonwealth Games on 3rd October 2010 and there was a fear that unsatisfactory sanitation systems might cause health and safety problems. Quantity: 1 digital cartoon(s).

Articles, UC QuakeStudies

A PDF of an article written by Dr Lucy D'Aeth (CDHB) titled "All Right? The question that starts a conversation about wellbeing". D'Aeth discusses the All Right? campaign in the context of research into peoples wellbeing following the Canterbury earthquake. The article was intended as a 'Perspectives Piece' in April 2013.

Images, UC QuakeStudies

A photograph of the rebuilt Blackwell's Department Store on the corner of Williams Street and Raven Quay in Kaiapoi. The department store was rebuilt after the previous building was damaged in the 2010 and 2011 Canterbury earthquakes. This photograph was modelled off an image taken by BeckerFraserPhotos in September 2010.

Images, Alexander Turnbull Library

Shows Bishop Victoria Matthews reading a brochure offering cheap deals for cathedrals and their various accoutrements. Context: refers to the debate about the fate of the Christchurch Cathedral. Bishop Victoria Matthews is in favour of demolishing the cathedral to a certain safe level. The lobby for saving the cathedral, wrecked by the earthquakes of 2010 and 2011, is very strong. Quantity: 1 digital cartoon(s).

Research papers, University of Canterbury Library

High-Force-to-Volume lead dampers (HF2V) have been recently developed through an experimental research program at University of Canterbury – New Zealand. Testing of the device and applications on beam column joints have demonstrated stable hysteretic behaviour with almost no damage. This paper reports testing of HF2V devices with straight, bulged and constricted shaft configurations subjected to velocities of 0.15 - 5.0mm/s. The effect of the shaft configuration on the hysteresis loop shape, design relationships and the effect of the velocity on the resistive force of the device are described. Results show that hysteresis loop shape of the device is almost square regardless of the shaft configuration, and that devices are characterized by noticeable velocity dependence in the range of 0.15-1.0mm/s.

Research papers, University of Canterbury Library

Results from cyclic undrained direct simple shear tests on reconstituted specimens of two sands from Christchurch are compared against the liquefaction resistance inferred from CPT-based empirical liquefaction triggering methods. Limitations in existing empirical triggering relationships to capture important effects related to processes which originated test soils are highlighted and discussed.

Videos, UC QuakeStudies

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.

Audio, Radio New Zealand

Te Pae, Christchurch's near $450 million convention centre, has been officially opened this afternoon with a pōwhiri and unveiling by Mayor Lianne Dalziel and Minister Megan Woods. Billed as a legacy for the city, it replaces the old centre which was demolished following the Canterbury earthquakes. Niva Chittock is at the ceremony and joins Lisa with the details.

Audio, Radio New Zealand

The Christchurch City Council's plans to to help curb a rising homeless population has left some people who live rough worried. The council is considering funding the Christchurch City Mission to employ outreach workers for the first time since the Canterbury earthquakes, and police are increasing central city patrols. Christchurch reporter Logan Church has the story.

Audio, Radio New Zealand

Displaced residents of Merivale Retirement village in Christchurch were told that they need to move out by April 1. A new facility that has replaced the earthquake damaged one won't have enough beds for everyone. The CEO of Age Concern Canterbury Simon Templeton talks about what measures are in place to look after these vulnerable elderly people.

Audio, Radio New Zealand

The old Ngaio Marsh theatre at the University of Canterbury was one of the many casualties of the earthquakes.The Student Association is encouraging people who performed on stage or helped out behind the scenes to buy a seat for the replacement Ngaio Marsh Theatre. Lynn Freeman talks with the UCSA president Sam Brosnahan about the project.

Audio, Radio New Zealand

A legal settlement between the Earthquake Commission and a group of Canterbury homeowners over the standard of quake repairs, is being described as a milestone for house owners throughout the country. The Reserve Bank has left the cost of borrowing unchanged at a record low 2-point-25 percent, athough it is signalling further cuts remain on the cards.

Audio, Radio New Zealand

Kaiapoi, just north of Christchurch, has unveiled a bold new plan for the parts of the town wiped off the map in the Canterbury earthquakes. The plan proposes having house boats on the river that runs through the town, there'll be a place for campervans to park up and a covered sports facility is on the cards.

Audio, Radio New Zealand

The government plans to introduce legislation to change the Earthquake Commission's operations, after a report found major failings. It found EQC was woefully unprepared as it dealt with the Canterbury quakes, and made dozens of recommendations about clarifying EQC's role and improving the way it deals with claimants. RNZ political reporter Yvette McCullough has more.