A man gets a phonecall from the Earthquake Commission (EQC) informing him that he can 'remediate and build here again!' The call comes just as another aftershock happens causing the family and pets to huddle in a terrified crowd as the house collapses around them and they find themselves waist-deep in mud and water. Refers to the Canterbury earthquake of 4th September and its continuing aftershocks as well as the problems surrounding rebuilding. Quantity: 1 digital cartoon(s).
As a three-year-old in China, Quin Tang's mother was shot in front of her and her father taken away. After moving to Christchurch 25 years ago, she walked out of an abusive marriage with two young children, no money and speaking little English. Tang then attended Canterbury University, teaching herself to read English from the text books there. She attained four degrees with an A+ average, and began working as a psychiatrist and counsellor. Quin was working in the CTV building when it collapsed. She took two weeks off work to recover, then came back and began counselling other victims of the Christchurch earthquakes. She has written and self-published the story of her life, called Half a Walnut Tree.
The families of those who died in the CTV building's collapse during the Christchurch Earthquake in February of 2011 are vowing to continue their Fight For Justice after The Independent Police Conduct Authority rejected their complaint about the Police Investigation . The Police decided 3 years ago not to lay charges against the building's designer. Yesterday the families announced that the IPCA, the body that advised the Police, had told them that it had no jurisdiction over Crown Law. Families spokesperson, Maan Alkaisi, told reporter Conan Young that they will continue to push for somebody to be held to account. He wants a retired judge to take another look at the decision not to prosecute.
Survivors of our biggest national disasters say new guidelines will better supporting families in the wake of future tragedies. The new "Public Service Commission Model Standards" - to be released at parliament today - addresses what survivors say have been consistent shortcomings in the treatment by government agencies of those most closely affected by disaster. The standards were co-authored by the Pike River Families Group after consulting with families of survivors caught up with events such as the earthquake and mosque shootings in Christchurch, the Aramoana massacre, the Cave Creek platform collapse and the Whakaari White Island eruption. Sonya Rockhouse, who lost her son Ben in the Pike River mine explosion 12 years ago, spoke to Corin Dann.
Topics - The Parole Board has decided that Teina Pora should be released from prison. Pora has served 21 years of a life sentence for murdering and raping Susan Burdett in Auckland in 1992. He continues to protest his innocence, and he'll appear before the Privy Council in London at the end of the year in an effort to clear his name. A coroner's report criticises almost every aspect of the Fire Service's response to the CTV building collapse that killed 115 people in the February 2011 Christchurch earthquake. Gordon Matenga says more people, more resources, better communication and a better structure might have improved the chances of saving more lives that day.
In this edition: The report into the collapse of the CTV building in the Christchurch earthquake a year ago is released, the Maori Council lodges claims with the Waitangi tribunal that could throw a spanner in the works of the Government's asset sales programme, the Earthquake Recovery Minister nearing the end of his tether with the Christchurch City Council, more from the Pike River Royal Commission, Radio Live could face a potential one hundred thousand dollar fine under the electoral act over John Key's hour long radio show in the run up to the 2011 election, banks lift their collective profits for the second half of 2011 by 25 percent and the winners are announced at the 2012 Halberg Awards.
A photograph of Graeme Kershaw, Technician at the University of Canterbury Department of Physics and Astronomy, sitting among the damaged parts of the Townsend Telescope. The telescope was damaged during the 22 February 2011 earthquake, when the Observatory tower at the Christchurch Arts Centre collapsed. Kershaw has been given the task of restoring the telescope. In this photograph he is holding the telescope's clock drive. In the foreground there is a plaque reading, "The equatorial telescope and accessories in this observatory were presented to Canterbury College by James Townsend Esq. 1891. A large contribution towards the erection of the tower was made by the Canterbury Astronomical Society".
A photograph of Graeme Kershaw, Technician at the University of Canterbury Department of Physics and Astronomy, sitting among the damaged parts of the Townsend Telescope. The telescope was damaged during the 22 February 2011 earthquake, when the Observatory tower at the Christchurch Arts Centre collapsed. Kershaw has been given the task of restoring the telescope. In this photograph he is holding the telescope's clock drive. In the foreground there is a plaque reading, "The equatorial telescope and accessories in this observatory were presented to Canterbury College by James Townsend Esq. 1891. A large contribution towards the erection of the tower was made by the Canterbury Astronomical Society".
A video of an interview with New Zealand Fire Service Chief Executive and National Commander Paul Baxter, about the findings of the coronial inquest into the CTV building deaths. Coroner Gordon Matenga found that failures by the Fire Service and Urban Search and Rescue did not contribute to the deaths of eight students at the CTV site in the aftermath of the 22 February 2011 earthquake. Baxter talks about the importance of acknowledging the families of the deceased, and the changes and improvements that have been made by the New Zealand Fire Service since the collapse of the CTV building.
Damage to ceiling systems resulted in a substantial financial loss to building owners in the Canterbury earthquakes. In some buildings, collapse of ceilings could easily have resulted in severe injury to occupants. This paper summarizes the types of ceiling damage observed in the Canterbury earthquakes, and draws useful lessons from the observed performance of different types of ceiling systems. Existing ceiling manufacturing and installing practices/regulations in New Zealand are critically scrutinized to identify deficiencies, and measures are suggested to improve the practice so that the damage to ceilings and the resulting loss are minimized in future earthquakes.
Aerial footage of Christchurch recorded the day after the 22 February 2011 earthquake. The footage shows damage to the Smith City car park, the Cathedral of the Blessed Sacrament, the CTV Building, the PGC Building, the Durham Street Methodist Church, the Lyttelton Timeball Station, the roads alongside the Avon River, and the ChristChurch Cathedral. It also shows New Zealand Army road blocks outside the hospital, crushed buses on Colombo Street, a Royal New Zealand Navy vessel in Lyttelton Harbour, rock fall on the Summit Road, collapsed cliffs in Sumner and Redcliffs, tents set up in a park, flooding in New Brighton, and liquefaction in QEII Park.
Text reads 'Rebuilding projects'. The first of the two frames shows collapsed buildings in Christchurch after the earthquake and the second frame shows leader of the Labour Party Phil Goff sorely in need of 'credibility' as he makes the 'V' for victory sign with both hands. Context - the rebuilding of Christchurch after the earthquake of 22 March 2011 and Phil Goff's disastrous personal polling as 'preferred PM' and the concomitant problems for the Labour Party with elections in November of this year. Colour and black and white versions of this cartoon are available Quantity: 2 digital cartoon(s).
Two men sit safe amongst the devastation of an earthquake surrounded by collapsed buildings and crushed cars; one has his head in his hands and the other says 'Remind me what we were all arguing about before all this'. Context - on 22 February 2011 a 6.3 magnitude earthquake struck in Christchurch which has probably killed more than 200 people (at this point the number is still not known) and caused very severe damage. The second man is aware of the relative unimportance of petty squabbles and differences of opinion against the enormity of the earthquake. Quantity: 1 digital cartoon(s).
The cartoon shows a digger dredging through the rubble and digging up a red heart representing 'hope' (Tom Scott doesn't do colour so this is significant). A rescuer nearby yells 'Careful! It's still beating'. Context - on 22 February 2011 a 6.3 magnitude earthquake struck in Christchurch which has probably killed more than 200 people (at this point the number is still not known) and caused much more severe damage. There were many people trapped in collapsed buildings and it was apparent in only two or three days that in most cases they could not have survived but of course people still held out impossible hope. Quantity: 1 digital cartoon(s).
A man wearing shorts and gumboots stands surrounded by liquefaction beside his collapsing house. He tries to phone the 'Quake helpline' for assistance and gets the response 'You have reached the quake helpline... If you're up to your knees in liquefaction... Press 1. If your house is down around your ears... Press 2. If you're looking for assistance or answers press on'. Context - The increasing frustration and misery of many Christchurch residents who are experiencing huge difficulty getting assistance after months of delays and continuing aftershocks following the Christchurch earthquakes of 4th September, 22 February and the two most recent ones on 13 June. Quantity: 1 digital cartoon(s).
A rat in a business suit representing 'insurance companies' carries a briefcase labelled 'Total replacement policies' and follows a fellow rat into a large hole 'loop holes' that leads into a collapsed building. The rat says 'Woo-hoo! Home sweet home!' Context - Problems for people whose houses were damaged in the Christchurch earthquakes. One of the options presented to residents in the red zone, ideal for people with replacement policies, was the government bought your land, and you dealt directly with your insurers about your house. However they got a shock when insurers told them they won't replace their homes, they'll only repair them, even though they're earmarked for certain demolition. Quantity: 1 digital cartoon(s).
A rescue worker carries the dead body of a woman out of the crumbled remains of a building. Nearby is a copy of the 'Building Code'. Context - there are questions being asked about whether some of the buildings that collapsed too readily in the Christchurch earthquake of 22 February 2011 had been subject to stringent enough building code regulations. The Department of Building and Housing said the vertical shaking in the central business district was both extreme and unusual and early indications suggest it was much more violent than designed for in the building code standards which are based on the kind of shaking expected to happen every 500 years. Quantity: 1 digital cartoon(s).
In the period between September 2010 and December 2011, Christchurch (New Zealand) and its surroundings were hit by a series of strong earthquakes including six significant events, all generated by local faults in proximity to the city: 4 September 2010 (Mw=7.1), 22 February 2011 (Mw=6.2), 13 June 2011 (Mw=5.3 and Mw=6.0) and 23 December 2011 (M=5.8 and (M=5.9) earthquakes. As shown in Figure 1, the causative faults of the earthquakes were very close to or within the city boundaries thus generating very strong ground motions and causing tremendous damage throughout the city. Christchurch is shown as a lighter colour area, and its Central Business District (CBD) is marked with a white square area in the figure. Note that the sequence of earthquakes started to the west of the city and then propagated to the south, south-east and east of the city through a set of separate but apparently interacting faults. Because of their strength and proximity to the city, the earthquakes caused tremendous physical damage and impacts on the people, natural and built environments of Christchurch. The 22 February 2011 earthquake was particularly devastating. The ground motions generated by this earthquake were intense and in many parts of Christchurch substantially above the ground motions used to design the buildings in Christchurch. The earthquake caused 182 fatalities, collapse of two multi-storey reinforced concrete buildings, collapse or partial collapse of many unreinforced masonry structures including the historic Christchurch Cathedral. The Central Business District (CBD) of Christchurch, which is the central heart of the city just east of Hagley Park, was practically lost with majority of its 3,000 buildings being damaged beyond repair. Widespread liquefaction in the suburbs of Christchurch, as well as rock falls and slope/cliff instabilities in the Port Hills affected tens of thousands of residential buildings and properties, and shattered the lifelines and infrastructure over approximately one third of the city area. The total economic loss caused by the 2010-2011 Christchurch earthquakes is currently estimated to be in the range between 25 and 30 billion NZ dollars (or 15% to 18% of New Zealand’s GDP). After each major earthquake, comprehensive field investigations and inspections were conducted to document the liquefaction-induced land damage, lateral spreading displacements and their impacts on buildings and infrastructure. In addition, the ground motions produced by the earthquakes were recorded by approximately 15 strong motion stations within (close to) the city boundaries providing and impressive wealth of data, records and observations of the performance of ground and various types of structures during this unusual sequence of strong local earthquakes affecting a city. This paper discusses the liquefaction in residential areas and focuses on its impacts on dwellings (residential houses) and potable water system in the Christchurch suburbs. The ground conditions of Christchurch including the depositional history of soils, their composition, age and groundwater regime are first discussed. Detailed liquefaction maps illustrating the extent and severity of liquefaction across Christchurch triggered by the sequence of earthquakes including multiple episodes of severe re-liquefaction are next presented. Characteristic liquefaction-induced damage to residential houses is then described focussing on the performance of typical house foundations in areas affected by liquefaction. Liquefaction impacts on the potable water system of Christchurch is also briefly summarized including correlation between the damage to the system, liquefaction severity, and the performance of different pipe materials. Finally, the characteristics of Christchurch liquefaction and its impacts on built environment are discussed in relation to the liquefaction-induced damage in Japan during the 11 March 2011 Great East Japan Earthquake.
Unreinforced masonry (URM) structures comprise a majority of the global built heritage. The masonry heritage of New Zealand is comparatively younger to its European counterparts. In a country facing frequent earthquakes, the URM buildings are prone to extensive damage and collapse. The Canterbury earthquake sequence proved the same, causing damage to over _% buildings. The ability to assess the severity of building damage is essential for emergency response and recovery. Following the Canterbury earthquakes, the damaged buildings were categorized into various damage states using the EMS-98 scale. This article investigates machine learning techniques such as k-nearest neighbors, decision trees, and random forests, to rapidly assess earthquake-induced building damage. The damage data from the Canterbury earthquake sequence is used to obtain the forecast model, and the performance of each machine learning technique is evaluated using the remaining (test) data. On getting a high accuracy the model is then run for building database collected for Dunedin to predict expected damage during the rupture of the Akatore fault.
Following a damaging earthquake, the immediate emergency response is focused on individual collapsed buildings or other "hotspots" rather than the overall state of damage. This lack of attention to the global damage condition of the affected region can lead to the reporting of misinformation and generate confusion, causing difficulties when attempting to determine the level of postdisaster resources required. A pre-planned building damage survey based on the transect method is recommended as a simple tool to generate an estimate of the overall level of building damage in a city or region. A methodology for such a transect survey is suggested, and an example of a similar survey conducted in Christchurch, New Zealand, following the 22 February 2011 earthquake is presented. The transect was found to give suitably accurate estimates of building damage at a time when information was keenly sought by government authorities and the general public. VoR - Version of Record
This paper begins with a discussion of the history of negligent manslaughter in New Zealand and its development from the standard of ordinary negligence to the current test of a “major departure” from the expected standard of care, as set out under s 150A of the Crimes Act 1961. The paper then examines failings in s 150A’s current application, arguing that the “major departure” test has created injustices due to its strictly objective nature. Two examples of this are discussed in-depth, Bawa-Garba v R (UK) where a doctor was convicted of grossly negligent manslaughter for the death of her patient; and the decision not to prosecute the negligent engineers of the CTV building which collapsed in the Christchurch earthquake of 2011. The paper discusses three potential resolutions moving forward. It concludes that a more subjective interpretation of the wording of s 150A, which takes account of circumstances excusing or condemning a defendant’s conduct, would prevent future injustices and be a reasonably open interpretation on the wording of s 150A.
Tax, water and housing concerns were all debated at length by Bill English and Jacinda Ardern in last night's TVNZ leaders debate. The debate came just an hour after shock 1 News Colmar Brunton poll put Labour out in front. There have been fires and explosions at a flood damaged chemical plant near Houston forcing the evacuation of people in nearby homes. A block of flats in Aro Street has been evacuated after a large slip has come down behind it. After heavy rains and flooding a Mumbai building has collapsed, killing at least 23 people. Biosecurity officials say they expect to decide by the end of the year whether they will need to order the destruction of dairy herds to wipe out a cow disease that's broken out in the South Island. It's been revealed that not a single one of New Zealand's 315 police buildings constructed before 2011 have had a full earthquake safety check. People who've bought houses in Canterbury since the September 2010 earthquake and are still battling with insurance companies over repairs, have been told that if they want to take the matter to court, today is their last chance. The Government has begun urgent talks with Australia over the Queensland's state government's "discriminatory" trade policy which takes effect today. Trade Minister Todd McClay joins us.
As part of the 'Project Masonry' Recovery Project funded by the New Zealand Natural Hazards Research Platform, commencing in March 2011, an international team of researchers was deployed to document and interpret the observed earthquake damage to masonry buildings and to churches as a result of the 22nd February 2011 Christchurch earthquake. The study focused on investigating commonly encountered failure patterns and collapse mechanisms. A brief summary of activities undertaken is presented, detailing the observations that were made on the performance of and the deficiencies that contributed to the damage to approximately 650 inspected unreinforced clay brick masonry (URM) buildings, to 90 unreinforced stone masonry buildings, to 342 reinforced concrete masonry (RCM) buildings, to 112 churches in the Canterbury region, and to just under 1100 residential dwellings having external masonry veneer cladding. In addition, details are provided of retrofit techniques that were implemented within relevant Christchurch URM buildings prior to the 22nd February earthquake and brief suggestions are provided regarding appropriate seismic retrofit and remediation techniques for stone masonry buildings. http://www.nzsee.org.nz/publications/nzsee-quarterly-bulletin/
The cartoon shows the Christchurch Anglican Cathedral tower in ruins and without its steeple. Above the drawing is the date '22.2.11'. A second version shows a huge magnitude 6.3 earthquake tremor on a seismic graph on top of which is the date '22.2.11'. Context - 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. The cathedral tower has collapsed and there has been devastating damage to the remaining structure. The Cathedral is one of around six sites of extreme concern around the city where many are believed to still be trapped. This earthquake followed on from an original magnitude 7.1 earthquake on 4 September 2010 which did far less damage and in which no-one died. Two versions of this cartoon are available Quantity: 2 digital cartoon(s).
The Catholic Cathedral is classified as a category 1 listed heritage building constructed largely of unreinforced stone masonry, and was significantly damaged in the recent Canterbury earthquakes of 2010 and 2011. In the 2010 event the building presented slight to moderta damage, meanwhile in the 2011 one experienced ground shaking in excess of its capacity leading to block failures and partial collapse of parts of the building, which left the building standing but still posing a significant hazard. In this paper we discuss the approach to develop the earthquake analysis of the building by 3D numerical simulations, and the results are compared/calibrated with the observed damage of the 2010 earthquake. Very accurate records were obtained during both earthquakes due to a record station located least than 80 m of distance from the building and used in the simulations. Moreover it is included in the model the soil structure interaction because it was observed that the ground and foundation played an important role on the seismic behavior of the structure. A very good agreement was found between the real observed damage and the nonlinear dynamic simulations described trough inelastic deformation (cracking) and building´s performance.
This paper presents site-specific and spatially-distributed ground-motion intensity estimates which have been utilized in the aftermath of the 2010-2011 Canterbury, New Zealand earthquakes. The methodology underpinning the ground motion intensity estimation makes use of both prediction models for ground motion intensity and its within-event spatial correlation. A key benefit of the methodology is that the estimated ground motion intensity at a given location is not a single value but a distribution of values. The distribution is comprised of both a mean and standard deviation, with the standard deviation being a function of the distance to nearby observations at strong motion stations. The methodology is illustrated for two applications. Firstly, maps of conditional peak ground acceleration (PGA) have been developed for the major events in the Canterbury earthquake sequence, which among other things, have been utilized for assessing liquefaction triggering susceptibility of land in residential areas. Secondly, the conditional distribution of response spectral ordinates is obtained at the location of the Canterbury Television building (CTV), which catastrophically collapsed in the 22 February 2011 earthquake. The conditional response spectra provide insight for the selection of ground motion records for use in forensic seismic response analyses of important structures at locations where direct recordings are absent.
One of the failure modes that got the attention of researchers in the 2011 February New Zealand earthquake was the collapse of a key supporting structural wall of Grand Chancellor Hotel in Christchurch which failed in a brittle manner. However, until now this failure mode has been still a bit of a mystery for the researchers in the field of structural engineering. Moreover, there is no method to identify, assess and design the walls prone to such failure mode. Following the recent break through regarding the mechanism of this failure mode based on experimental observations (out-of-plane shear failure), a numerical model that can capture this failure was developed using the FE software DIANA. A comprehensive numerical parametric study was conducted to identify the key parameters contributing to the development of out-of-plane shear failure in reinforced concrete (RC) walls. Based on the earthquake observations, experimental and numerical studies conducted by the authors of this paper, an analytical method to identify walls prone to out-of-plane shear failure that can be used in practice by engineers is proposed. The method is developed based on the key parameters affecting the seismic performance of RC walls prone to out-of-plane shear failure and can be used for both design and assessment purposes
Capacity design and hierarchy of strength philosophies at the base of modern seismic codes allow inelastic response in case of severe earthquakes and thus, in most traditional systems, damage develops at well-defined locations of reinforced concrete (RC) structures, known as plastic hinges. The 2010 and 2011 Christchurch earthquakes have demonstrated that this philosophy worked as expected. Plastic hinges formed in beams, in coupling beams and at the base of columns and walls. Structures were damaged permanently, but did not collapse. The 2010 and 2011 Christchurch earthquakes also highlighted a critical issue: the reparability of damaged buildings. No methodologies or techniques were available to estimate the level of subsequent earthquakes that RC buildings could still sustain before collapse. No repair techniques capable of restoring the initial condition of buildings were known. Finally, the cost-effectiveness of an eventual repair intervention, when compared with a new building, was unknown. These aspects, added to nuances of New Zealand building owners’ insurance coverage, encouraged the demolition of many buildings. Moreover, there was a perceived strong demand from government and industry to develop techniques for assessing damage to steel reinforcement bars embedded in cracked structural concrete elements. The most common questions were: “Have the steel bars been damaged in correspondence to the concrete cracks?”, “How much plastic deformation have the steel bars undergone?”, and “What is the residual strain capacity of the damaged bars?” Minimally invasive techniques capable of quantifying the level and extent of plastic deformation and residual strain capacity are not yet available. Although some studies had been recently conducted, a validated method is yet to be widely accepted. In this thesis, a least-invasive method for the damage-assessment of steel reinforcement is developed. Based on the information obtained from hardness testing and a single tensile test, it is possible to estimate the mechanical properties of earthquake-damaged rebars. The reduction in the low-cycle fatigue life due to strain ageing is also quantified. The proposed damage assessment methodology is based on empirical relationships between hardness and strain and residual strain capacity. If damage is suspected from in situ measurements, visual inspection or computer analysis, a bar may be removed and more accurate hardness measurements can be obtained using the lab-based Vickers hardness methodology. The Vickers hardness profile of damaged bars is then compared with calibration curves (Vickers hardness versus strain and residual strain capacity) previously developed for similar steel reinforcement bars extracted from undamaged locations. Experimental tests demonstrated that the time- and temperature-dependent strain-ageing phenomenon causes changes in the mechanical properties of plastically deformed steels. In particular, yield strength and hardness increases, whereas ductility decreases. The changes in mechanical properties are quantified and their implications on the hardness method are highlighted. Low-cycle fatigue (LCF) failures of steel reinforcing bars have been observed in laboratory testing and post-earthquake damage inspections. Often, failure might not occur during a first seismic event. However, damage is accumulated and the remaining fatigue life is reduced. Failure might therefore occur in a subsequent seismic event. Although numerous studies exist on the LCF behaviour of steel rebars, no studies had been conducted on the strain-ageing effects on the remaining fatigue life. In this thesis, the reduction in fatigue life due to this phenomenon is determined through a number of experimental tests.
To this extent, modern buildings generally demonstrated good resistance to collapse during the recent earthquakes in New Zealand. However, damage to non-structural elements (NSE) has been persistent during these events. NSEs include secondary systems or components attached to the floors, roofs, and walls of a building or industrial facility that are not explicitly designed to participate in the main vertical or lateral load-bearing mechanism of the structure. They play a major role in the operational and functional aspects of buildings and contribute a major portion of the building’s overall cost. Therefore, they are expected to accommodate the effects of seismic actions such as drifts and accelerations. Typical examples of NSEs include internal non-loadbearing partitions, suspended ceilings, sprinkler piping systems, architectural claddings, building contents, mechanical/electrical equipment, and furnishings. The main focus of this thesis is the drift sensitive NSEs: precast concrete cladding panels and internal partition walls. Even though most precast concrete cladding panels performed well from a life-safety point of view during recent earthquakes in NZ, some collapsed panels posed a significant threat to life safety. It is, therefore, important that the design and detailing of the panel-to-structure connections ensure that their strength and displacement capacity are adequate to meet the corresponding seismic demands, at least during design level earthquakes. In contrast, the partition wall is likely to get damaged and lose serviceability at a low inter-story drift unless designed to accommodate the relative deformations between them and the structure. Partition walls suffered wide-ranging damage such as screw failures, diagonal cracking, detachments to the gypsum linings, and anchorage failures during the 2011 Canterbury Earthquake Sequence in NZ. Therefore, the thesis is divided into two parts. Part I of the thesis focuses on developing novel low-damage precast concrete cladding panel connections, i.e. “rocking” connection details comprising vertically slotted steel embeds and weld plates. The low-damage seismic performance of novel “rocking” connection details is verified through experimental tests comprising uni-directional, bi-directional, and multi-storey scaled quasi-static cyclic tests. Comparison with the seismic performance of traditional panel connections reported in the literature demonstrated the system’s significantly improved seismic resilience. Furthermore, the finite element models of panel connections and sealants are developed in ABAQUS. The force-drift responses of the “rocking” panel system modelled in SAP2000 is compared with the experimental results to evaluate their accuracy and validity. Part II of the thesis focuses on a) understanding the seismic performance of traditional rigid timber-framed partition wall, b) development and verification of low-damage connections (i.e. “rocking” connection details comprising of dual-slot tracks), and c) seismic evaluation of partition walls with a novel “bracketed and slotted” connections (comprising of innovative fastener and plastic bracket named Flexibracket) under uni-directional and bidirectional quasi-static cyclic loadings. Moreover, parametric investigation of the partition walls was conducted through several experimental tests to understand better the pros and cons of the rocking connection details. The experimental results have confirmed that the implementation of the proposed low damage solutions of precast cladding panels and internal partition walls can significantly reduce their damage in a building.
The 4th of September 2010 Mw 7.1 Darfield (Canterbury) earthquake had generated significant ground shaking within the Christchurch Central Business District (CBD). Despite the apparently significant shaking, the observed structural damage for pre-1970s reinforced concrete (RC) buildings was indeed limited and lower than what was expected for such typology of buildings. This paper explores analytically and qualitatively the different aspects of the "apparent‟ good seismic performance of the pre-1970s RC buildings in the Christchurch CBD, following the earthquake reconnaissance survey by the authors. Damage and building parameters survey result, based on a previously established inventory of building stock of these non-ductile RC buildings, is briefly reported. From an inventory of 75 buildings, one building was selected as a numerical case-study to correlate the observed damage with the non-linear analyses. The result shows that the pre-1970s RC frame buildings performed as expected given the intensity of the ground motion shaking during the Canterbury earthquake. Given the brittle nature of this type of structure, it was demonstrated that more significant structural damage and higher probability of collapse could occur when the buildings were subjected to alternative input signals with different frequency content and duration characteristics and still compatible to the seismicity hazard for Christchurch CBD.