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Research papers, The University of Auckland Library

The author followed five primary (elementary) schools over three years as they responded to and began to recover from the 2010–2011 earthquakes in and around the city of Christchurch in the Canterbury region of New Zealand. The purpose was to capture the stories for the schools themselves, their communities, and for New Zealand’s historical records. From the wider study, data from the qualitative interviews highlighted themes such as children’s responses or the changing roles of principals and teachers. The theme discussed in this article, however, is the role that schools played in the provision of facilities and services to meet (a) physical needs (food, water, shelter, and safety); and (b) emotional, social, and psychological needs (communication, emotional support, psychological counseling, and social cohesion)—both for themselves and their wider communities. The role schools played is examined across the immediate, short-, medium-, and long-term response periods before being discussed through a social bonding theoretical lens. The article concludes by recommending stronger engagement with schools when considering disaster policy, planning, and preparation http://www.schoolcommunitynetwork.org/SCJ.aspx

Research papers, The University of Auckland Library

Many large-scale earthquakes all over the world have highlighted the impact of soil liquefaction to the built environment, but the scale of liquefaction-induced damage experienced in Christchurch and surrounding areas following the 2010-2011 Canterbury earthquake sequence (CES) was unparalleled, especially in terms of impact to an urban area. The short time interval between the large earthquakes presented a very rare occasion to examine liquefaction mechanism in natural deposits. The re-liquefaction experienced by the city highlighted the high liquefaction susceptibility of soil deposits in Christchurch, and presented a very challenging problem not only to the local residents but to the geotechnical engineering profession. This paper summarises the lessons learned from CES, and the impacts of the observations made to the current practice of liquefaction assessment and mitigation.

Research papers, The University of Auckland Library

In the aftermath of the 2010-2011 Canterbury earthquakes in New Zealand, the residual capacity and reparability of damaged reinforced concrete (RC) structures was an issue pertinent to building owners, insurers, and structural engineers. Three precast RC moment-resisting frame specimens were extracted during the demolition of the Clarendon Tower in Christchurch after sustaining earthquake damage. These specimens were subjected to quasi-static cyclic testing as part of a research program to determine the reparability of the building. It was concluded that the precast RC frames were able to be repaired and retrofitted to an enhanced strength capacity with no observed reduction in displacement capacity, although the frames with “shear-ductile” detailing exhibited less displacement ductility capacity and energy dissipation capacity than the more conventionally detailed RC frames. Furthermore, the cyclic test results from the earthquake-damaged RC frames were used to verify the predicted inelastic demands applied to the specimens during the 2010-2011 Canterbury earthquakes. https://www.concrete.org/publications/acistructuraljournal.aspx

Research papers, The University of Auckland Library

An UnReinforced clay brick Masonry (URM) chimney is composed of a cantilever URM appendage above a roofline and is considered one of the most earthquake prone non-structural compo¬nents within vintage URM and timber-framed buildings. Observations from past earthquakes including the 1992 Big Bear City earthquake, 1994 Northridge earthquake, 2001 Nisqually earthquake, 2010/2011 Canterbury earthquakes, 2012 Northern Italy earthquakes, and 2014 South Napa earthquake served repeatedly as a reminder of the hazard induced by URM chimneys. The observed failure types included several cases where the adopted retrofit techniques were not adequate to effectively secure chimneys dur¬ing the earthquake. Data collected during the 2010/2011 post-earthquake building assessments in Christchurch and insur¬ance claims are reported herein. Five full-scale solid clay brick URM chimneys which replicated the most encountered geometrical and construction characteristics were subjected to shake table testing. Two chim¬ney samples were representative of the as-built conditions, while three samples were retrofitted using two different configurations of Near-Surface-Mounted (NSM) Carbon-Fibre-Reinforced-Polymer (CFRP) strips and post-tensioning techniques. The adopted securing techniques allowed an increase in seismic acceleration capacity of more than five times for chimneys constructed with ultra-weak mortar and more than twice for chimneys built with weak mortar. http://www.16ibmac.com/

Research papers, The University of Auckland Library

The connections between walls of unreinforced masonry (URM) buildings and flexible timber diaphragms are critical building components that must perform adequately before desirable earthquake response of URM buildings may be achieved. Field observations made during the initial reconnaissance and the subsequent damage surveys of clay brick URM buildings following the 2010/2011 Canterbury, New Zealand, earthquakes revealed numerous cases where anchor connections joining masonry walls or parapets with roof or floor diaphragms appeared to have failed prematurely. These observations were more frequent for adhesive anchor connections than for through-bolt connections (i.e., anchorages having plates on the exterior facade of the masonry walls). Subsequently, an in-field test program was undertaken in an attempt to evaluate the performance of adhesive anchor connections between unreinforced clay brick URM walls and roof or floor diaphragm. The study consisted of a total of almost 400 anchor tests conducted in eleven existing URM buildings located in Christchurch, Whanganui and Auckland. Specific objectives of the study included the identification of failure modes of adhesive anchors in existing URM walls and the influence of the following variables on anchor load-displacement response: adhesive type, strength of the masonry materials (brick and mortar), anchor embedment depth, anchor rod diameter, overburden level, anchor rod type, quality of installation, and the use of metal mesh sleeves. In addition, the comparative performance of bent anchors (installed at an angle of minimum 22.5° to the perpendicular projection from the wall surface) and anchors positioned horizontally was investigated. Observations on the performance of wall-to-diaphragm connections in the 2010/2011 Canterbury earthquakes, a summary of the performed experimental program and test results, and a proposed pull-out capacity relationship for adhesive anchors installed into multi-leaf clay brick masonry are presented herein. AM - Accepted Manuscript

Research papers, The University of Auckland Library

Following the 2010/2011 Canterbury earthquakes the seismic design of buildings with precast concrete panels has received significant attention. Although this form of construction generally performed adequately in Christchurch, there were a considerable number of precast concrete panel connection failures. This observation prompted a review of more than 4700 panel details from 108 buildings to establish representative details used in both existing and new multi-storey and low rise industrial precast concrete buildings in three major New Zealand cities of Auckland, Wellington and Christchurch. Details were collected from precast manufacturers and city councils and were categorised according to type. The detailing and quantity of each reviewed connection type in the sampled data is reported, and advantages and potential deficiencies of each connection type are discussed. The results of this survey provide a better understanding of the relative prevalence of common detailing used in precast concrete panels and guidance for the design of future experimental studies. http://www.nzsee.org.nz/publications/nzsee-quarterly-bulletin/

Research papers, The University of Auckland Library

A dramatic consequence of the Christchurch, New Zealand, earthquakes of 2010 and 2011 was the widespread liquefaction in the city. Part of the central business district (CBD) was badly affected by liquefaction but elsewhere large volumes of ejecta were not evident for those parts of the CBD where the upper layers in the soil profile are sandy gravel and gravelly sand. The purpose of the paper is to investigate the effect of the gravel permeability on the rise and dissipation of excess pore water pressure during cyclic loading of a soil profile idealised from Christchurch data. The Cyclic1D software, which performs one-dimensional non-linear effective stress site response analysis, was used. Permeability values associated with gravel were found to suppress the cyclic accumulation of excess pore water pressure in gravel layers. Given that there has not been any systematic measurement of the in situ permeability of the gravels in Christchurch, the modelling in the paper suggests that likely values for the bulk permeability of the gravel layers are within the range suggested in the geotechnical literature. However, the work reported is of wider application than Christchurch and emphasises the controlling influence of permeability on the accumulation and dissipation of cyclic pore pressures. VoR - Version of Record

Research papers, The University of Auckland Library

A number of field testing techniques, such as standard penetration test (SPT), cone penetration test (CPT), and Swedish weight sounding (SWS), are popularly used for in-situ characterisation. The screw driving sounding (SDS) method, which has been recently developed in Japan, is an improved version of the SWS technique and measures more parameters, including the required torque, load, speed of penetration and rod friction; these provide more robust way of characterising soil stratigraphy. It is a cost-efficient technique which uses a machine-driven and portable device, making it ideal for testing in small-scale and confined areas. Moreover, with a testing depth of up to 10-15m, it is suitable for liquefaction assessment. Thus, the SDS method has great potential as an in-situ testing method for geotechnical site characterisation, especially for residential house construction. In this paper, the results of SDS tests performed at a variety of sites in New Zealand are presented. The soil database was employed to develop a soil classification chart based on SDS-derived parameters. Moreover, using the data obtained following the 2010-2011 Christchurch Earthquake Se-quence, a methodology was established for liquefaction potential evaluation using SDS data. http://www.isc5.com.au/wp-content/uploads/2016/09/1345-2-ORENSE.pdf

Research papers, The University of Auckland Library

Eccentrically Braced Frames (EBFs) are a widely used seismic resisting structural steel system. Since their inception in the late 1970s, they have been a viable option with an available stiffness that is between simple braced systems and moment resisting systems. A similar concept, the linked column frame (LCF), uses shear links between two closely spaced columns. In both cases, the key component is the active link or the shear link, and this component is the objective of this study. The performance of high rise EBF buildings in the 2010 and 2011 Christchurch earthquakes was beyond that which was expected, especially considering the very high accelerations recorded. As the concrete high-rises were torn down, two EBF buildings remained standing and only required some structural repair. These events prompted a renewed interest in bolted shear links, as well as their performance. While some research into replaceable shear links had already been done (Mansour, 2011), the objectives of this study were to improve on the shear link itself, with the consideration that links built in the future are likely to be bolted. The main components of this study were to: 1. Reduce or eliminate the requirements for intermediate web stiffeners, as they were suspected of being detrimental to performance. Furthermore, any reduction in stiffening requirements is a direct fabrication cost saving. Links with low web aspect ratios were found to achieve exceptional ductilities when no stiffeners were included, prompting new design equations. 2. Ensure that the stresses in the ends of links are adequately transferred into the endplates without causing fractures. Although most of the experimental links had web doubler plates included, four had varied lengths of such doubler plates from 0.0 in. to 8.0 in. The link without any doubler plates performed to a similar level to its peers, and thus it is likely that links with quality end details may not need web doubler plates at all. 3. Evaluate the performance of a link with double sided stiffeners without the use of web welds, as opposed to conventional single sided, welded stiffeners. This link performed well, and web-weld-less double sided stiffeners may be an economical alternative to conventional stiffeners for deeper sections of links. 4. Evaluate the performance of a link with thin endplates that are made efficient with the use of gusset plates. This link performed to an acceptable level and provides evidence for a cost effective alternative to thick endplates, especially considering the high overstrength end moments in links, typically requiring 16-bolt connections. 5. Examine the potential use of an alternative EBF arrangement where the collector beam is over sized, and the link section is formed by cutting out parts of the beam's web. After running a series of finite element models each with a unique variation, a number of approximate design rules were derived such that future research could develop this idea further experimentally. 6. Ensure that during testing, the secondary elements (members that are not the shear link), do not yield and are not close to yielding. None of the instrumented elements experienced any unexpected yielding, however the concerns for high stresses in the collector beam panel zone during design were warranted. The use of an existing New Zealand design equation is recommended as an extra check for design codes worldwide. The above objectives were mainly conducted experimentally, except: the data set for item 1 was greatly expanded through the use of a calibrated numerical model which was then used in an extensive parametric study; item 5 was purely finite element based; and, a small parametric study was included for item 3 in an attempt to expand on the trends found there.

Research papers, The University of Auckland Library

Unreinforced masonry (URM) cavity-wall construction is a form of masonry where two leaves of clay brick masonry are separated by a continuous air cavity and are interconnected using some form of tie system. A brief historical introduction is followed by details of a survey undertaken to determine the prevalence of URM cavity-wall buildings in New Zealand. Following the 2010/2011 Canterbury earthquakes it was observed that URM cavity-walls generally suffered irreparable damage due to a lack of effective wall restraint and deficient cavity-tie connections, combined with weak mortar strength. It was found that the original cavity-ties were typically corroded due to moisture ingress, resulting in decreased lateral loadbearing capacity of the cavity-walls. Using photographic data pertaining to Christchurch URM buildings that were obtained during post-earthquake reconnaissance, 252 cavity-walls were identified and utilised to study typical construction details and seismic performance. The majority (72%, 182) of the observed damage to URM cavity-wall construction was a result of out-of-plane type wall failures. Three types of out-of-plane wall failure were recognised: (1) overturning response, (2) one-way bending, and (3) two-way bending. In-plane damage was less widely observed (28%) and commonly included diagonal shear cracking through mortar bed joints or bricks. The collected data was used to develop an overview of the most commonly-encountered construction details and to identify typical deficiencies in earthquake response that can be addressed via the selection and implementation of appropriate mitigation interventions. http://www.journals.elsevier.com/structures

Research papers, The University of Auckland Library

In September 2010 and February 2011 the Canterbury region of New Zealand was struck by two powerful earthquakes, registering magnitude 7.1 and 6.3 respectively on the Richter scale. The second earthquake was centred 10 kilometres south-east of the centre of Christchurch (the region’s capital and New Zealand’s third most populous urban area, with approximately 360,000 residents) at a depth of five kilometres. 185 people were killed, making it the second deadliest natural disaster in New Zealand’s history. (66 people were killed in the collapse of one building alone, the six-storey Canterbury Television building.) The earthquake occurred during the lunch hour, increasing the number of people killed on footpaths and in buses and cars by falling debris. In addition to the loss of life, the earthquake caused catastrophic damage to both land and buildings in Christchurch, particularly in the central business district. Many commercial and residential buildings collapsed in the tremors; others were damaged through soil liquefaction and surface flooding. Over 1,000 buildings in the central business district were eventually demolished because of safety concerns, and an estimated 70,000 people had to leave the city after the earthquakes because their homes were uninhabitable. The New Zealand Government declared a state of national emergency, which stayed in force for ten weeks. In 2014 the Government estimated that the rebuild process would cost NZ$40 billion (approximately US$27.3 billion, a cost equivalent to 17% of New Zealand’s annual GDP). Economists now estimate it could take the New Zealand economy between 50 and 100 years to recover. The earthquakes generated tens of thousands of insurance claims, both against private home insurance companies and against the New Zealand Earthquake Commission, a government-owned statutory body which provides primary natural disaster insurance to residential property owners in New Zealand. These ranged from claims for hundreds of millions of dollars concerning the local port and university to much smaller claims in respect of the thousands of residential homes damaged. Many of these insurance claims resulted in civil proceedings, caused by disputes about policy cover, the extent of the damage and the cost and/or methodology of repairs, as well as failures in communication and delays caused by the overwhelming number of claims. Disputes were complicated by the fact that the Earthquake Commission provides primary insurance cover up to a monetary cap, with any additional costs to be met by the property owner’s private insurer. Litigation funders and non-lawyer claims advocates who took a percentage of any insurance proceeds also soon became involved. These two factors increased the number of parties involved in any given claim and introduced further obstacles to resolution. Resolving these disputes both efficiently and fairly was (and remains) central to the rebuild process. This created an unprecedented challenge for the justice system in Christchurch (and New Zealand), exacerbated by the fact that the Christchurch High Court building was itself damaged in the earthquakes, with the Court having to relocate to temporary premises. (The High Court hears civil claims exceeding NZ$200,000 in value (approximately US$140,000) or those involving particularly complex issues. Most of the claims fell into this category.) This paper will examine the response of the Christchurch High Court to this extraordinary situation as a case study in innovative judging practices and from a jurisprudential perspective. In 2011, following the earthquakes, the High Court made a commitment that earthquake-related civil claims would be dealt with as swiftly as the Court's resources permitted. In May 2012, it commenced a special “Earthquake List” to manage these cases. The list (which is ongoing) seeks to streamline the trial process, resolve quickly claims with precedent value or involving acute personal hardship or large numbers of people, facilitate settlement and generally work proactively and innovatively with local lawyers, technical experts and other stakeholders. For example, the Court maintains a public list (in spreadsheet format, available online) with details of all active cases before the Court, listing the parties and their lawyers, summarising the facts and identifying the legal issues raised. It identifies cases in which issues of general importance have been or will be decided, with the expressed purpose being to assist earthquake litigants and those contemplating litigation and to facilitate communication among parties and lawyers. This paper will posit the Earthquake List as an attempt to implement innovative judging techniques to provide efficient yet just legal processes, and which can be examined from a variety of jurisprudential perspectives. One of these is as a case study in the well-established debate about the dialogic relationship between public decisions and private settlement in the rule of law. Drawing on the work of scholars such as Hazel Genn, Owen Fiss, David Luban, Carrie Menkel-Meadow and Judith Resnik, it will explore the tension between the need to develop the law through the doctrine of precedent and the need to resolve civil disputes fairly, affordably and expeditiously. It will also be informed by the presenter’s personal experience of the interplay between reported decisions and private settlement in post-earthquake Christchurch through her work mediating insurance disputes. From a methodological perspective, this research project itself gives rise to issues suitable for discussion at the Law and Society Annual Meeting. These include the challenges in empirical study of judges, working with data collected by the courts and statistical analysis of the legal process in reference to settlement. September 2015 marked the five-year anniversary of the first Christchurch earthquake. There remains widespread dissatisfaction amongst Christchurch residents with the ongoing delays in resolving claims, particularly insurers, and the rebuild process. There will continue to be challenges in Christchurch for years to come, both from as-yet unresolved claims but also because of the possibility of a new wave of claims arising from poor quality repairs. Thus, a final purpose of presenting this paper at the 2016 Meeting is to gain the benefit of other scholarly perspectives and experiences of innovative judging best practice, with a view to strengthening and improving the judicial processes in Christchurch. This Annual Meeting of the Law and Society Association in New Orleans is a particularly appropriate forum for this paper, given the recent ten year anniversary of Hurricane Katrina and the plenary session theme of “Natural and Unnatural Disasters – human crises and law’s response.” The presenter has a personal connection with this theme, as she was a Fulbright scholar from New Zealand at New York University in 2005/2006 and participated in the student volunteer cleanup effort in New Orleans following Katrina. http://www.lawandsociety.org/NewOrleans2016/docs/2016_Program.pdf