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).
The objective of this project is to collect perishable seismic response data from the baseisolated Christchurch Women's Hospital. The strong and continuing sequence of aftershocks presents a unique opportunity to capture high-fidelity data from a modern base-isolated facility. These measurements will provide quantitative information required to assess the mechanisms at play in this and in many other seismically-isolated structures.
This paper presents an overview of the soil profile characteristics at strong motion station (SMS) locations in the Christchurch Central Business District (CBD) based on recently completed geotechnical site investigations. Given the variability of Christchurch soils, detailed investigations were needed in close vicinity to each SMS. In this regard, CPT, SPT and borehole data, and shear wave velocity (Vs) profiles from surface wave dispersion data in close vicinity to the SMSs have been used to develop detailed representative soil profiles at each site and to determine site classes according to the New Zealand standard NZS1170.5. A disparity between the NZS1170.5 site classes based on Vs and SPT N60 investigation techniques is highlighted, and additional studies are needed to harmonize site classification based on these techniques. The short period mode of vibration of soft deposits above gravels, which are found throughout Christchurch, are compared to the long period mode of vibration of the entire soil profile to bedrock. These two distinct modes of vibration require further investigation to determine their impact on the site response. According to current American and European approaches to seismic site classification, all SMSs were classified as problematic soil sites due to the presence of liquefiable strata, soils which are not directly accounted for by the NZS1170.5 approach.
A review of the week's news including... National MP Todd Barclay falls on his sword while Labour is in damage control, the decision to not prosecute the Pike River Mine CEO is to be contested in the Supreme Court, the lawyer for Akshay Chand says she sought bail on his behalf believing his mother and aunt would monitor his every movement, The Education Ministry is forced to apologise for its flawed handling of school closures and mergers after the 2011 Canterbury earthquake, The Health Minister is forced to defend his embattled Ministry following a major budget blunder, employment lawyers aren't surprised another health sector group is taking a pay equity claim, Ministry for Primary Industries officials come under fire at a packed Stewart Island public meeting on the cull of the island's farmed oysters, it's Plan B for a crowd funded initiative that wants to take control of Dunedin's Cadbury factory and All Black great Sir Colin 'pinetree' Meads has been immortalised in bronze.
Text across the top of the cartoon reads 'The reminder again' and shows a disaster kit in a box labeled 'Your B-Ready Disaster Kit'. Nearby are newspapers recording the text 'no power', 'shortage of blankets', 'boil water'. Context - a warning for everyone to prepare disaster kits brought home by the Christchurch earthquake of 22 February 2011. On 22 February 2011 at 12:51 pm (NZDT), Christchurch experienced a major magnitude 6.3 earthquake, which resulted in severe damage and many casualties. A National State of Emergency has been declared. This followed on from an original magnitude 7.1 earthquake on 4 September 2010 which did far less damage and in which no-one died. Quantity: 1 digital cartoon(s).
Recent field investigations were carried out to define the shear wave velocity (VS) profile and site periods across the Canterbury region, supplementing earlier efforts in urban Christchurch. Active source surface wave testing, ambient wave field (passive) and H/V spectral ratio methods were used to characterise the soil profile in the region. H/V spectral ratio peaks indicate site periods in the range of 5-7 seconds across much of the Canterbury Plains, broadly consistent with those based on a 1D velocity model for the region. Site periods decrease rapidly in the vicinity of the Canterbury foothills and the Banks Peninsula outcrops. In Christchurch, the Riccarton Gravels result in a significant mode of vibration that has a much shorter period than the site period of the entire soil column down to basement rock.
The old (or is that the new) Inland Revenue Department (IRD) building on the corner of Madras and Cashel Streets in central Christchurch. Built in 2006/07 on the site of the former Farmers department store (itself badly damaged by fire), it was just a few years old when the earthquake of February 2011 struck, and subsequent quakes (all through 2...
The September 2010 Canterbury and February 2011 Christchurch earthquakes and associated aftershocks have shown that the isolator displacement in Christchurch Women's Hospital (Christchurch City's only base-isolated structure) was significantly less than expected. Occupant accounts of the events have also indicated that the accelerations within the hospital superstructure were larger than would usually be expected within a base-isolated structure and that residual low-level shaking lasts for a longer period of time following the strong-motion of an event than for non-isolated structures.
Following the 22 February 2011, MW 6.2 earthquake located on a fault beneath the Port Hills of Christchurch, fissuring of up to several hundred metres in length was observed in the loess and loess-colluvium of foot-slope positions in north-facing valleys of the Port Hills. The fissuring was observed in all major valleys, occurred at similar low altitudes, showing a contour-parallel orientation and often accompanied by both lateral compression/extension features and spring formation in the valley floor below. Fissuring locations studied in depth included Bowenvale Valley, Hillsborough Valley, Huntlywood Terrace–Lucas Lane, Bridle Path Road, and Maffeys Road–La Costa Lane. Investigations into loess soil, its properties and mannerisms, as well as international examples of its failure were undertaken, including study of the Loess Plateau of China, the Teton Dam, and palaeo-fissuring on Banks Peninsula. These investigations lead to the conclusion that loess has the propensity to fail, often due to the infiltration of water, the presence of which can lead to its instantaneous disaggregation. Literature study and laboratory analysis of Port Hills loess concluded that is has the ability to be stable in steep, sub-vertical escarpments, and often has a sub-vertically jointed internal structure and has a peak shear strength when dry. Values for cohesion, c (kPa) and the internal friction angle, ϕ (degrees) of Port Hills loess were established. The c values for the 40 Rapaki Road, 3 Glenview Terrace loess samples were 13.4 kPa and 19.7 kPa, respectively. The corresponding ϕ values were thought unusually high, at 42.0° and 43.4°.The analysed loess behaved very plastically, with little or no peak strength visible in the plots as the test went almost directly to residual strength. A geophysics resistivity survey showed an area of low resistivity which likely corresponds to a zone of saturated clayey loess/loess colluvium, indicating a high water table in the area. This is consistent with the appearances of local springs which are located towards the northern end of each distinct section of fissure trace and chemical analysis shows that they are sourced from the Port Hills volcanics. Port Hills fissuring may be sub-divided into three categories, Category A, Category B, and Category C, each characterised by distinctive features of the fissures. Category A includes fissures which display evidence of, spring formation, tunnel-gullying, and lateral spreading-like behaviour or quasi-toppling. These fissures are several metres down-slope of the loess-bedrock interface, and are in valleys containing a loess-colluvium fill. Category B fissures are in wider valleys than those in Category A, and the valleys contain estuarine silty sediments which liquefied during the earthquake. Category C fissures occurred at higher elevations than the fissures in the preceding categories, being almost coincident with bedrock outcropping. It is believed that the mechanism responsible for causing the fissuring is a complex combination of three mechanisms: the trampoline effect, bedrock fracturing, and lateral spreading. These three mechanisms can be applied in varying degrees to each of the fissuring sites in categories A, B, and C, in order to provide explanation for the observations made at each. Toppling failure can describe the soil movement as a consequence of the a three causative mechanisms, and provides insight into the movement of the loess. Intra-loess water coursing and tunnel gullying is thought to have encouraged and exacerbated the fissuring, while not being the driving force per se. Incipient landsliding is considered to be the least likely of the possible fissuring interpretations.
Porritt Park was, before the earthquakes, the headquarters of hockey in this region. Two astro-turf fields (the main one was other side of the building), and corporate offices etc. The earthquakes buckled all the playing surfaces and damaged the buildings; a couple of smaller ones have been removed. Hockey shifted the other side of the city t...
This presentation summarizes the development of high-resolution surficial soil velocity models in the Canterbury, New Zealand basin. Shallow (<30m) shear wave velocities were primarily computed based on a combination of a large database of over 15,000 cone penetration test (CPT) logs in and around Christchurch, and a recently-developed Christchurch-specific empirical correlation between soil shear wave velocity and CPT. Large active-source testing at 22 locations and ambient-wavefield surface wave and H/V testing at over 80 locations were utilized in combination with 1700 water well logs to constrain the inter-bedded stratigraphy and velocity of Quaternary sediments up to depths of several hundred meters. Finally, seismic reflection profiles and the ambient-wavefield surface wave data provide constraint on velocities from several hundred meters to several kilometres. At all depths, the high resolution data illustrates the complexity of the soil conditions in the region, and the developed 3D models are presently being used in broadband ground motion simulations to further interpret the observed strong ground motions in the 2010-2011 Canterbury earthquake sequence.
© 2018 Springer Nature B.V. This study compares seismic losses considering initial construction costs and direct-repair costs for New Zealand steel moment-resisting frame buildings with friction connections and those with extended bolted-end-plate connections. A total of 12 buildings have been designed and analysed considering both connection types, two building heights (4-storey and 12-storey), and three locations around New Zealand (Auckland, Christchurch, and Wellington). It was found that buildings with friction connections required design to a higher design ductility, yet are generally stiffer due to larger beams being required to satisfy higher connection overstrength requirements. This resulted in the frames with friction connections experiencing lower interstorey drifts on most floors but similar peak total floor accelerations, and subsequently incurring lower drift-related seismic repair losses. Frames with friction connections tended to have lower expected net-present-costs within 50 years of the building being in service for shorter buildings and/or if located in regions of high seismicity. None of the frames with friction connections in Auckland showed any benefits due to the low seismicity of the region.
<b>New Zealand has experienced several strong earthquakes in its history. While an earthquake cannot be prevented from occurring, planning can reduce its consequences when it does occur. This dissertation research examines various aspects of disaster risk management policy in Aotearoa New Zealand.</b> Chapter 2 develops a method to rank and prioritise high-rise buildings for seismic retrofitting in Wellington, the earthquake-prone capital city of New Zealand. These buildings pose risks to Wellington’s long-term seismic resilience that are of clear concern to current and future policymakers. The prioritization strategy we propose, based on multi-criteria decision analysis (MCDA) methods, considers a variety of data on each building, including not only its structural characteristics, but also its location, its economic value to the city, and its social importance to the community around it. The study demonstrates how different measures, within four general criteria – life safety, geo-spatial location of the building, its economic role, and its socio-cultural role – can be operationalized into a viable framework for determining retrofitting/demolition policy priorities. Chapter 3 and chapter 4 analyse the Residential Red Zone (RRR) program that was implemented in Christchurch after the 2011 earthquake. In the program, approximately 8,000 homeowners were told that their homes were no longer permittable, and they were bought by the government (through the Canterbury Earthquake Recovery Authority). Chapter 3 examines the subjective wellbeing of the RRR residents (around 16000 people) after they were forced to move. We consider three indicators of subjective wellbeing: quality of life, stress, and emotional wellbeing. We found that demographic factors, health conditions, and the type of government compensation the residents accepted, were all significant determinants of the wellbeing of the Red Zone residents. More social relations, better financial circumstances, and the perception of better government communication were also all associated positively with a higher quality of life, less stress, and higher emotional wellbeing. Chapter 4 concentrates on the impact of this managed retreat program on RRR residents’ income. We use individual-level comprehensive, administrative, panel data from Canterbury, and difference in difference evaluation method to explore the effects of displacement on Red Zone residential residents. We found that compared to non-relocated neighbours, the displaced people experience a significant initial decrease in their wages and salaries, and their total income. The impacts vary with time spent in the Red Zone and when they moved away. Wages and salaries of those who were red-zoned and moved in 2011 were reduced by 8%, and 5.4% for those who moved in 2012. Females faced greater decreases in wages and salaries, and total income, than males. There were no discernible impacts of the relocation on people’s self-employment income.
This poster provides a summary of the development of a 3D shallow (z<40m) shear wave velocity (Vs) model for the urban Christchurch, New Zealand region. The model is based on a recently developed Christchurch-specific empirical correlation between Vs and cone penetration test (CPT) data (McGann et al. 2014a,b) and the large high-density database of CPT logs in the greater Christchurch urban area (> 15,000 logs as of 01/01/2014). In particular, the 3D model provides shear wave velocities for the surficial Springston Formation, Christchurch Formation, and Riccarton gravel layers which generally comprise the upper 40m in the Christchurch urban area. Point-estimates are provided on a 200m-by- 200m grid from which interpolation to other locations can be performed. This model has applications for future site characterization and numerical modeling efforts via maps of timeaveraged Vs over specific depths (e.g. Vs30, Vs10) and via the identification of typical Vs profiles for different regions and soil behaviour types within Christchurch. In addition, the Vs model can be used to constrain the near-surface velocities for the 3D seismic velocity model of the Canterbury basin (Lee et al. 2014) currently being developed for the purpose of broadband ground motion simulation.
Recurrent liquefaction in Christchurch during the 2010-2011 Canterbury earthquake sequence created a wealth of shallow subsurface intrusions with geometries and orientations governed by (1) strong ground motion severity and duration, and (2) intrinsic site characteristics including liquefaction susceptibility, lateral spreading severity, geomorphic setting, host sediment heterogeneity, and anthropogenic soil modifications. We present a suite of case studies that demonstrate how each of these characteristics influenced the geologic expressions of contemporary liquefaction in the shallow subsurface. We compare contemporary features with paleo-features to show how geologic investigations of recurrent liquefaction can provide novel insights into the shaking characteristics of modern and paleo-earthquakes, the influence of geomorphology on liquefaction vulnerability, and the possible controls of anthropogenic activity on the geologic record. We conclude that (a) sites of paleo-liquefaction in the last 1000-2000 years corresponded with most severe liquefaction during the Canterbury earthquake sequence, (b) less vulnerable sites that only liquefied in the strongest and most proximal contemporary earthquakes are unlikely to have liquefied in the last 1000-2000 years or more, (c) proximal strong earthquakes with large vertical accelerations favoured sill formation at some locations, (d) contemporary liquefaction was more severe than paleoliquefaction at all study sites, and (e) stratigraphic records of successive dike formation were more complete at sites with severe lateral spreading, (f) anthropogenic fill suppressed surface liquefaction features and altered subsurface liquefaction architecture.
Severe liquefaction was repeatedly observed during the 2010 - 2011 C hristchurch earthquake s , particularly affecting deposits of fine sands and silty sands of recent fluvial or estuarine origin. The effects of liquefaction included major sliding of soil tow ard water bodies ( i.e. lateral spreading ) rang ing from centimetres to several metres. In this paper, a series of undrained cyclic torsional shear tests were conducted to evaluate the liquefaction and extremely large deformation properties of Christchurch b oiled sand . In these tests, the simple shear conditions were reproduced in order to apply realistic stress conditions that soil s experience in the field during horizontal seismic shaking. Several hollow cylindrical medium dense specimens ( D r = 50%) were pr epared by pluviation method, isotropically consolidated at an effective stress of 100 kPa and then cyclically sheared under undrained conditions up to 10 0% double amplitude shear strain (γ DA ) . The cyclic strength at different levels of γ DA of 7.5%, 15%, 3 0 % and 6 0%, development of extremely large post - liquefaction deformation and shear strain locali s ation properties were assessed from the analysis of the effective stress paths and stress - strain responses . To reveal possible distinctiveness, the cyclic undra ined behaviour of CHCH boiled sand was compared with that of Toyoura sand previously examined under similar testing conditions
Lake Taupō in New Zealand is associated with frequent unrest and small to moderate eruptions. It presents a high consequence risk scenario with immense potential for destruction to the community and the surrounding environment. Unrest associated with eruptions may also trigger earthquakes. While it is challenging to educate people about the hazards and risks associated with multiple eruptive scenarios, effective education of students can lead to better mitigation strategies and risk reduction. Digital resources with user-directed outcomes have been successfully used to teach action oriented skills relevant for communication during volcanic crisis [4]. However, the use of choose your own adventure strategies to enhance low probability risk literacy for Secondary school outreach has not been fully explored. To investigate how digital narrative storytelling can mediate caldera risk literacy, a module “The Kid who cried Supervolcano” will be introduced in two secondary school classrooms in Christchurch and Rotorua. The module highlights four learning objectives: (a) Super-volcanoes are beautiful but can be dangerous (b) earthquake (unrest) activity is normal for super-volcanoes (c) Small eruptions are possible from super-volcanoes and can be dangerous in our lifetimes (d) Super-eruptions are unlikely in our lifetimes. Students will create their digital narrative using the platform Elementari (www.elementari.io). The findings from this study will provide clear understanding of students’ understanding of risk perceptions of volcanic eruption scenarios and associated hazards and inform the design of educational resources geared towards caldera risk literacy.
In the aftermath of the 22 February 2011 earthquake, the Natural Hazards Research Platform (NHRP) initiated a series of Short Term Recovery Projects (STRP) aimed at facilitating and supporting the recovery of Christchurch from the earthquake impacts. This report presents the outcomes of STRP 6: Impacts of Liquefaction on Pipe Networks, which focused on the impacts of liquefaction on the potable water and wastewater systems of Christchurch. The project was a collaborative effort of NHRP researchers with expertise in liquefaction, CCC personnel managing and designing the systems and a geotechnical practitioner with experience/expertise in Christchurch soils and seismic geotechnics.
Prime Minister John Key stands grinning on a cracked pedestal bearing the words 'Most popular P.M.' In the background is the Beehive flying a skull and crossbones flag. The landscape is a desert with cactus and dried bones and a vulture in a bare tree. A man and a woman comment that it looks as though the quake may have done damage in Wellington after all, that and the crash of the SCF fund. Refers to two major events in the Canterbury area in recent times that have incurred huge government costs; these are the collapse of the South Canterbury Finance Company and the earthquake that struck early Saturday morning 4th September. The South Canterbury Finance Company has been taken into receivership by the government which has guaranteed that all 30,000 fortunate high-risk investors will be paid out $1.6b thanks to the taxpayer. Treasury is assuming that the cost of the earthquake will reach $4 billion, including $2 billion worth of estimated damage to private dwellings and their contents, $1 billion of damage to commercial property, and $1 billion worth of damage to public infrastructure. There is a colour and a black and white version of this cartoon Quantity: 2 digital cartoon(s).
With origins in the South Bronx area of New York in the early 1970s, hip-hop culture is now produced and consumed globally. While hip-hop activities can be varied, hip-hop is generally considered to have four forms or “elements”: DJing, MCing, b-boying/b-girling, and graffiti. Although all four elements of hip-hop have become a part of many youth work initiatives across the globe, public debate and controversy continue to surround hip-hop activities. Very little research and literature has explored the complexities involved in the assembling of hip-hop activities in youth work sites of practice using these hip-hop elements. This study attends to the gap in hip-hop and human service literature by tracing how hip-hop activities were assembled in several sites of youth work activity in Christchurch, New Zealand. Actor-network theory (ANT) is the methodological framework used to map the assemblage of hip-hop-youth work activities in this study. ANT follows how action is distributed across both human and non-human actors. By recognising the potential agency of “things”, this research traces the roles played by human actors, such as young people and youth workers, together with those of non-human actors such as funding documents, social media, clothing, and youth venue equipment. This ethnographic study provides rich descriptions or “snapshots” of some of the key socio-material practices that shaped the enactment of hip-hop-youth work activities. These are derived from fieldwork undertaken between October 2009 and December 2011, where participant observation took place across a range of sites of hip-hop-youth work activity. In addition to this fieldwork, formal interviews were undertaken with 22 participants, the majority being youth workers, young people, and youth trust administrators. The ANT framework reveals the complexity of the task of assembling hip-hop in youth work worlds. The thesis traces the work undertaken by both human and non-human actors in generating youth engagement in hip-hop-youth work activities. Young people’s hip-hop interests are shown to be varied, multiple, and continually evolving. It is also shown how generating youth interest in hip-hop-youth work activities involved overcoming young people’s indifference or lack of awareness of the hip-hop resources a youth trust had on offer. Furthermore, the study highlights where hip-hop activities were edited or “tinkered” with to avoid hip-hop “bads”. The thesis also unpacks how needed resources were enlisted, and how funders’ interests were translated into supporting hip-hop groups and activities. By tracing the range of actors mobilised to enact hip-hop-youth work activities, this research reveals how some youth trusts could avoid having to rely on obtaining government funds for their hip-hop activities. The thesis also includes an examination of one youth trust’s efforts to reconfigure its hip-hop activities after the earthquakes that struck Christchurch city in 2010 and 2011. Working both in and on the world, the text that is this thesis is also understood as an intervention. This study constitutes a deliberate attempt to strengthen understandings of hip-hop as a complex, multiple, and fluid entity. It therefore challenges traditional media and literature representations that simplify and thus either stigmatise or celebrate hip-hop. As such, this study opens up possibilities to consider the opportunities, as well as the complexities of assembling hip-hop in youth work sites of practice.
<b>Aotearoa has undoubtedly some of the most beautiful landscapes in the world, a privilege for its inhabitants. However, as our cities have developed post-colonisation, the connection between the natural environment and its occupants has diminished. Designers play a vital role within an ever evolving world to progress the built environment in a way that reflects and restores vital values that have been deprioritised. Future practice should prioritise diversity, care for the land, enhancement of community space, and sustainable practices.</b> This research sets out to demonstrate that new design methodologies can encourage kaitiakitanga, whilst meeting the needs of urban public space. Initially through critical analysis and literature based research, a study of Ōtautahi Christchurch, the South Island’s largest city, was undertaken. The principles of a ‘15 minute city’ were also explored and applied to the city, establishing issues within the built environment that drove the overall research direction. Through the tools of critical reflection and a research through design methodology, a design toolkit was constructed. This toolkit sets out to provide designers with a simple streamlined method of developing urban interventions that are sustainable and beneficial for human well-being. The toolkit incorporates an abstraction of the ‘15 minute city’ ideology and introduces the concepts of evolving green transportation routes within cities. Ōtautahi Christchurch, a city with a significant history of earthquake-caused damage, was chosen as the primary site for the application of this research’s proposed toolkit. The city becomes a canvas for an urban rebuild that explores and aims to set a precedent for a progressive 21st-century city. A key finding as the toolkit research developed was the idea of a ‘temporary’ phase or intervention, being added to traditional design methodologies prior to permanent building. The research explains how this temporary phase could more actively engage diverse user groups and create active conversations between communities and designers. The refined toolkit sets outs proposed timeline phases, methods of site analysis and development of design drivers. Alongside this, a modular architectural system establishes a design proposal for the temporary phase of an individual site within an evolving green route. This outcome provides further opportunity for realistic testing, which would actively involve communities and aims to shift our priorities within urban development. The introduction of the ‘temporary’ phase is beneficial in mitigating psychological implications on people and limiting physical impacts on the landscape. The final design stage of the thesis applied the toolkit process to three sites in Ōtautahi Christchurch. Through a holistic lens, the toolkit framework set out methods to collate information that provides guidance for development on the sites. While some layers are initiated simply by recognising site characteristics, others are informed through software such as GIS. Connected by a proposed green transport route, the three initial sites are developed with temporary interventions that utilise the modular design set out previously in the research. Contextualising the interventions on real world sites tested the flexibility of the system and allowed for critical reflection on the applicability of the toolkit to Aotearoa. The research concludes by identifying future research opportunities and speculates on possible applications of its findings within the real world. Temporary Permanence highlights the significant role that we, as designers, have in shifting urban priorities to create more holistic, sustainable, and inclusive cities for people and the planet.
On 4 September 2010, a magnitude Mw 7.1 earthquake struck the Canterbury region on the South Island of New Zealand. The epicentre of the earthquake was located in the Darfield area about 40 km west of the city of Christchurch. Extensive damage occurred to unreinforced masonry buildings throughout the region during the mainshock and subsequent large aftershocks. Particularly extensive damage was inflicted to lifelines and residential houses due to widespread liquefaction and lateral spreading in areas close to major streams, rivers and wetlands throughout Christchurch and Kaiapoi. Despite the severe damage to infrastructure and residential houses, fortunately, no deaths occurred and only two injuries were reported in this earthquake. From an engineering viewpoint, one may argue that the most significant aspects of the 2010 Darfield Earthquake were geotechnical in nature, with liquefaction and lateral spreading being the principal culprits for the inflicted damage. Following the earthquake, a geotechnical reconnaissance was conducted over a period of six days (10–15 September 2010) by a team of geotechnical/earthquake engineers and geologists from New Zealand and USA (GEER team: Geo-engineering Extreme Event Reconnaissance). JGS (Japanese Geotechnical Society) members from Japan also participated in the reconnaissance team from 13 to 15 September 2010. The NZ, GEER and JGS members worked as one team and shared resources, information and logistics in order to conduct thorough and most efficient reconnaissance covering a large area over a very limited time period. This report summarises the key evidence and findings from the reconnaissance.
This paper provides a photographic tour of the ground-surface rupture features of the Greendale Fault, formed during the 4th September 2010 Darfield Earthquake. The fault, previously unknown, produced at least 29.5 km of strike-slip surface deformation of right-lateral (dextral) sense. Deformation, spread over a zone between 30 and 300 m wide, consisted mostly of horizontal flexure with subsidiary discrete shears, the latter only prominent where overall displacement across the zone exceeded about 1.5 m. A remarkable feature of this event was its location in an intensively farmed landscape, where a multitude of straight markers, such as fences, roads and ditches, allowed precise measurements of offsets, and permitted well-defined limits to be placed on the length and widths of the surface rupture deformation.
The cartoon is entitled 'seismic upheaval'. Prime Minister John Key and Finance Minister Bill English stand near great seismic cracks in the ground and stare sadly at a huge wallet, 'Bill's boodle', belonging to Bill English. Vast quantities of banknotes spill out of the cash pocket in the wallet which also contains a 'travel card', a 'house card' and an 'expenses card'. The various cards in the wallet refer to expense account embarrassments relating to Bill English. Etched in the ground are the words 'Christchurch quake' and 'South Canterbury Finance'. The cartoon refers to two major events in the Canterbury area in recent times that have incurred huge government costs; these are the collapse of the South Canterbury Finance Company and the earthquake that struck early Saturday morning 4th September. The South Canterbury Finance Company has been taken into receivership by the government which has guaranteed that all 30,000 fortunate high-risk investors will be paid out $1.6b thanks to the taxpayer. Treasury is assuming that the cost of the earthquake will reach $4 billion, including $2 billion worth of estimated damage to private dwellings and their contents, $1 billion of damage to commercial property, and $1 billion worth of damage to public infrastructure. Quantity: 1 digital cartoon(s).
This report presents the simplified seismic assessment of a case study reinforced concrete (RC) building following the newly developed and refined NZSEE/MBIE guidelines on seismic assessment (NZSEE/MBIE, semi-final draft 26 October 2016). After an overview of the step-by-step ‘diagnostic’ process, including an holistic and qualitative description of the expected vulnerabilities and of the assessment strategy/methodology, focus is given, whilst not limited, to the implementation of a Detailed Seismic Assessment (DSA) (NZSEE/MBIE, 2016c). The DSA is intended to provide a more reliable and consistent outcome than what can be provided by an initial seismic assessment (ISA). In fact, while the Initial Seismic Assessment (ISA), of which the Initial Evaluation Procedure is only a part of, is the more natural and still recommended first step in the overall assessment process, it is mostly intended to be a coarse evaluation involving as few resources as reasonably possible. It is thus expected that an ISA will be followed by a Detailed Seismic Assessment (DSA) not only where the threshold of 33%NBS is not achieved but also where important decisions are intended that are reliant on the seismic status of the building. The use of %NBS (% New Building Standard) as a capacity/demand ratio to describe the result of the seismic assessment at all levels of assessment procedure (ISA through to DSA) is deliberate by the NZSEE/MBIE guidelines (Part A) (NZSEE/MBIE 2016a). The rating for the building needs only be based on the lowest level of assessment that is warranted for the particular circumstances. Discussion on how the %NBS rating is to be determined can be found in Section A3.3 (NZSEE/MBIE 2016a), and, more specifically, in Part B for the ISA (NZSEE/MBIE 2016b) and Part C for the DSA (NZSEE/MBIE 2016c). As per other international approaches, the DSA can be based on several analysis procedures to assess the structural behaviour (linear, nonlinear, static or dynamic, force or displacement-based). The significantly revamped NZSEE 2016 Seismic Assessment Guidelines strongly recommend the use of an analytical (basically ‘by hand’) method, referred to the Simple Lateral Mechanism Analysis (SLaMA) as a first phase of any other numerically-based analysis method. Significant effort has thus been dedicated to provide within the NZSEE 2016 guidelines (NZSEE/MBIE 2016c) a step-by-step description of the procedure, either in general terms (Chapter 2) or with specific reference to Reinforced Concrete Buildings (Chapter 5). More specifically, extract from the guidelines, NZSEE “recommend using the Simple Lateral Mechanism Analysis (SLaMA) procedure as a first step in any assessment. While SLaMA is essentially an analysis technique, it enables assessors to investigate (and present in a simple form) the potential contribution and interaction of a number of structural elements and their likely effect on the building’s global capacity. In some cases, the results of a SLaMA will only be indicative. However, it is expected that its use should help assessors achieve a more reliable outcome than if they only carried out a detailed analysis, especially if that analysis is limited to the elastic range For complex structural systems, a 3D dynamic analysis may be necessary to supplement the simplified nonlinear Simple Lateral Mechanism Analysis (SLaMA).” This report presents the development of a full design example for the the implementation of the SLaMA method on a case study buildings and a validation/comparison with a non-linear static (pushover) analysis. The step-by-step-procedure, summarized in Figure 1, will be herein demonstrated from a component level (beams, columns, wall elements) to a subassembly level (hierarchy of strength in a beam-column joint) and to a system level (frame, C-Wall) assuming initially a 2D behaviour of the key structural system, and then incorporating a by-hand 3D behaviour (torsional effects).
Since the early 1980s seismic hazard assessment in New Zealand has been based on Probabilistic Seismic Hazard Analysis (PSHA). The most recent version of the New Zealand National Seismic Hazard Model, a PSHA model, was published by Stirling et al, in 2012. This model follows standard PSHA principals and combines a nation-wide model of active faults with a gridded point-source model based on the earthquake catalogue since 1840. These models are coupled with the ground-motion prediction equation of McVerry et al (2006). Additionally, we have developed a time-dependent clustering-based PSHA model for the Canterbury region (Gerstenberger et al, 2014) in response to the Canterbury earthquake sequence. We are now in the process of revising that national model. In this process we are investigating several of the fundamental assumptions in traditional PSHA and in how we modelled hazard in the past. For this project, we have three main focuses: 1) how do we design an optimal combination of multiple sources of information to produce the best forecast of earthquake rates in the next 50 years: can we improve upon a simple hybrid of fault sources and background sources, and can we better handle the uncertainties in the data and models (e.g., fault segmentation, frequency-magnitude distributions, time-dependence & clustering, low strain-rate areas, and subduction zone modelling)? 2) developing revised and new ground-motion predictions models including better capturing of epistemic uncertainty – a key focus in this work is developing a new strong ground motion catalogue for model development; and 3) how can we best quantify if changes we have made in our modelling are truly improvements? Throughout this process we are working toward incorporating numerical modelling results from physics based synthetic seismicity and ground-motion models.
This study followed two similarly affected, but socio-economically disparate suburbs as residents responded to and attempted to recover from the devastating 6.3 magnitude earthquake that struck Christchurch, New Zealand, on February 22, 2011. More specifically, it focuses on the role of local churches, community-based organisations (CBOs) and non-governmental organisations (NGOs), here referred to broadly as civil society, in meeting the immediate needs of local residents and assisting with the longer-term recovery of each neighbourhood. Despite considerable socioeconomic differences between the two neighbourhoods, civil society in both suburbs has been vital in addressing the needs of locals in the short and long term following the earthquake. Institutions were able to utilise local knowledge of both residents and the extent of damage in the area to a) provide a swifter local response than government or civil defence and then help direct the relief these agencies provided locally; b) set up central points for distribution of supplies and information where locals would naturally gather; c) take action on what were perceived to be unmet needs; and d) act as a way of bridging locals to a variety of material, informational, and emotional resources. However the findings also support literature which indicates that other factors are also important in understanding neighbourhood recovery and the role of civil society, including: local leadership; a shared, place-based identity; the type and form of civil society organizations; social capital; and neighbourhood- and household-level indicators of relative vulnerability and inequality. The intertwining of these various factors seems to influence how these neighbourhoods have coped with and taken steps in recovering from this disaster. It is recommended that future research be directed at developing a better understanding of how this occurs. It is suggested that a model similar to Yasui’s (2007) Community Vulnerability and Capacity model be developed as a useful way to approach future research in this area.
The initial goal of this research was to explore how SME business models change in response to a crisis. Keeping this in mind, the business model canvas (Osterwalder & Pigneur, 2010) was used as a tool to analyse SME business models in the Canterbury region of New Zealand. The purpose was to evaluate the changes SMEs instituted in their business models after being hit by a series of earthquakes in 2010 and 2011. The idea was to conduct interviews with business owners and analyse them using grounded theory methods. As this method is iterative and requires simultaneous data collection and analysis, a tentative model was proposed after first phase of the data collection and analysis. However, as a result of this process, it became apparent that owner-specific characteristics, action orientation and networks were more prominent in the data than business model elements. Although the SMEs in this study experienced several operational changes in their business models, such as a change of location, modifications to their payment terms or expanded/restricted target markets, the suggested framework highlights how owner-specific attributes ensured the recovery of their businesses. After the initial framework was suggested, subsequent interviews were conducted to test, verify, and modify the tentative model. Three aspects of business recovery emerged: (a) cognitive coping – the business owner’s mind-set and motive; (b) adaptive coping – the ability of business owner to take corrective actions; and (c) social capital – the social network of a business owner, including formal and informal connections and their significance. Three distinct groups were identified; self-sufficient SMEs, socially-based SMEs and surviving SMEs. This thesis proposes a grounded theory of business recovery for SMEs following a disaster. Cognitive coping and social capital enabled the owners to take actions, which eventually led to the desired outcomes for the businesses.
On November 14 2016 a magnitude 7.8 earthquake struck the south island of New Zealand. The earthquake lasted for just two minutes with severe seismic shaking and damage in the Hurunui and Kaikōura districts. Although these are predominantly rural areas, with scattered small towns and mountainous topography, they also contain road and rail routes that are essential parts of the national transport infrastructure. This earthquake and the subsequent recovery are of particular significance as they represent a disaster following in close proximity to another similar disaster, with the Canterbury earthquakes occurring in a neighboring district five years earlier. The research used an inductive qualitative case study to explore the nature of the Kaikōura recovery. That recovery process involved a complex interplay between the three parties; (a) the existing local government in the district, (b) central government agencies funding the recovery of the local residents and the national transport infrastructure, and (c) recovery leaders arriving with recent expertise from the earlier Canterbury disaster. It was evident that three groups: locals, government, and experts represented a multi-party governance debate in which the control of the Kaikōura earthquake recovery was shared amongst them. Each party had their own expertise, adgenda and networks that they brought to the Kaikōura recovery, but this created tensions between external expertise and local, community leadership. Recent earthquake research suggests that New Zealand is currently in the midst of an earthquake cluster, with further seismic disasters likely to occur in relatively close succession. This is likely to be compounded by the increasing frequency of other natural disasters with the effects of climate change. The present study investigates a phenomenon that may become increasingly common, with the transfer of disaster expertise from one event to another, and the interface between those experts with local and national government in directing recoveries. The findings of this study have implications for practitioners and policy makers in NZ and other countries where disasters are experienced in close spatial and temporal proximity.
The timing of large Holocene prehistoric earthquakes is determined by dated surface ruptures and landslides at the edge of the Australia-Pacific plate boundary zone in North Canterbury, New Zealand. Collectively, these data indicate two large (M > 7) earthquakes during the last circa 2500 years, within a newly formed zone of hybrid strike-slip and thrust faulting herein described as the Porter's Pass-to-Amberley Fault Zone (PPAFZ). Two earlier events during the Holocene are also recognized, but the data prior to 2500 years are presumed to be incomplete. A return period of 1300–2000 years between large earthquakes in the PPAFZ is consistent with a late Holocene slip rate of 3–4 mm/yr if each displacement is in the range 4–8 m. Historical seismicity in the PPAFZ is characterized by frequent small and moderate magnitude earthquakes and a seismicity rate that is identical to a region surrounding the structurally mature Hope fault of the Marlborough Fault System farther north. This is despite an order-of-magnitude difference in slip rate between the respective fault zones and considerable differences in the recurrence rate of large earthquakes. The magnitude-frequency distribution in the Hope fault region is in accord with the characteristic earthquake model, whereas the rate of large earthquakes in the PPAFZ is approximated (but over predicted) by the Gutenberg-Richter model. The comparison of these two fault zones demonstrates the importance of the structural maturity of the fault zone in relation to seismicity rates inferred from recent, historical, and paleoseismic data.