The reality of just how many historic buildings will be lost to the Christchurch earthquake is now becoming apparent with Civil Defence adding another 123 buildings to the demolition list.
A video of an interview with Mayor Bob Parker, recorded at the Civil Defence Headquarters in the Christchurch Art Gallery on the evening of the 22 February 2011. Parker talks about the fatalities and damage caused by the 22 February 2011 earthquake.
A mobile toilet unit set up on Gloucester Street, outside the Christchurch Art Gallery. The art gallery was used as the temporary Civil Defence headquarters after the 22 February 2011 earthquakes.
University of Canterbury staff members are escorted by Civil Defence members in order to retrieve essential items from their offices. The photographer comments, "ICT network admins, Craig Miller and Aaron Eivers".
University of Canterbury staff members are escorted by Civil Defence members in order to retrieve essential items from their offices. The photographer comments, "E-learning team vacate their floor. (Blurry, sorry.)
An entry from Ruth Gardner's blog for 6 March 2011 entitled, "Day 13, 8am - inside the Christchurch cordon.".
Six months after the 4 September 2010 Mw 7.1 Darfield (Canterbury) earthquake, a Mw 6.2 Christchurch (Lyttelton) aftershock struck Christchurch on the 22 February 2011. This earthquake was centred approximately 10km south-east of the Christchurch CBD at a shallow depth of 5km, resulting in intense seismic shaking within the Christchurch central business district (CBD). Unlike the 4 Sept earthquake when limited-to-moderate damage was observed in engineered reinforced concrete (RC) buildings [35], in the 22 February event a high number of RC Buildings in the Christchurch CBD (16.2 % out of 833) were severely damaged. There were 182 fatalities, 135 of which were the unfortunate consequences of the complete collapse of two mid-rise RC buildings. This paper describes immediate observations of damage to RC buildings in the 22 February 2011 Christchurch earthquake. Some preliminary lessons are highlighted and discussed in light of the observed performance of the RC building stock. Damage statistics and typical damage patterns are presented for various configurations and lateral resisting systems. Data was collated predominantly from first-hand post-earthquake reconnaissance observations by the authors, complemented with detailed assessment of the structural drawings of critical buildings and the observed behaviour. Overall, the 22 February 2011 Mw 6.2 Christchurch earthquake was a particularly severe test for both modern seismically-designed and existing non-ductile RC buildings. The sequence of earthquakes since the 4 Sept 2010, particularly the 22 Feb event has confirmed old lessons and brought to life new critical ones, highlighting some urgent action required to remedy structural deficiencies in both existing and “modern” buildings. Given the major social and economic impact of the earthquakes to a country with strong seismic engineering tradition, no doubt some aspects of the seismic design will be improved based on the lessons from Christchurch. The bar needs to and can be raised, starting with a strong endorsement of new damage-resisting, whilst cost-efficient, technologies as well as the strict enforcement, including financial incentives, of active policies for the seismic retrofit of existing buildings at a national scale.
In order to provide information related to seismic vulnerability of non-ductile reinforced concrete (RC) frame buildings, and as a complementary investigation on innovative feasible retrofit solutions developed in the past six years at the University of Canterbury on pre-19170 reinforced concrete buildings, a frame building representative of older construction practice was tested on the shake table. The specimen, 1/2.5 scale, consists of two 3-storey 2-bay asymmetric frames in parallel, one interior and one exterior, jointed together by transverse beams and floor slabs. The as-built (benchmark) specimen was first tested under increasing ground motion amplitudes using records from Loma Prieta Earthquake (California, 1989) and suffered significant damage at the upper floor, most of it due to lap splices failure. As a consequence, in a second stage, the specimen was repaired and modified by removing the concrete in the lap splice region, welding the column longitudinal bars, replacing the removed concrete with structural mortar, and injecting cracks with epoxy resin. The modified as-built specimen was then tested using data recorded during Darfield (New Zealand, 2010) and Maule (Chile, 2010) Earthquakes, with whom the specimen showed remarkably different responses attributed to the main variation in frequency content and duration. In this contribution, the seismic performance of the three series of experiments are presented and compared.
An as-built reinforced concrete (RC) frame building designed and constructed according to pre-1970s code design construction practice has been recently tested on the shake table at the University of Canterbury. The specimen, 1/2.5 scaled version of the original prototype, consists of two 3-storey 2-bay asymmetric frames in parallel, one interior and one exterior, jointed together by transverse beams and floor slabs. Following the benchmark test, a retrofit intervention has been proposed to rehabilitate the tested specimen. In this paper, detailed information on the assessment and design of the seismic retrofit procedure using GFRP (glass fibre reinforced polymer) materials is given for the whole frame. Hierarchy of strength and sequence of events (damage mechanisms) in the panel zone region are evaluated using a moment-axial load (M-N) interaction performance domain, according to a performance-based retrofit philosophy. Specific limit states or design objectives are targeted with attention given to both strength and deformation limits. In addition, an innovative retrofit solution using FRP anchor dowels for the corner beam-column joints with slabs is proposed. Finally, in order to provide a practical tool for engineering practice, the retrofit procedure is provided in a step-by step flowchart fashion.
Recent advances in timber design at the University of Canterbury have led to new structural systems that are appropriate for a wide range of building types, including multi-storey commercial office structures. These buildings are competitive with more traditional construction materials in terms of cost, sustainability and structural performance. This paper provides seismic design recommendations and analytical modelling approaches, appropriate for the seismic design of post-tensioned coupled timber wall systems. The models are based on existing seismic design theory for precast post-tensioned concrete, modified to more accurately account for elastic deformation of the timber wall systems and the influence of the floor system. Experimental test data from a two storey post-tensioned timber building, designed, constructed and tested at the University of Canterbury is used to validate the analytical models.
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.
An overview of the 22 February 2011 Christchurch earthquake is presented in the context of characterization of extreme/rare events. Focus is given to the earthquake source, observed near-source strong ground motions, and effects of site response, while structural response and consequences are mentioned for completeness. For each of the above topics comparisons and discussions are made with predictive models for each of phenomena considered. In light of the observations and predictive model comparisons, the author’s opinion on improving the characterization of such extreme/rare events, and their appropriate consideration in seismic design is presented
This paper describes pounding damage sustained by buildings and bridges in the February 2011 Christchurch earthquake. Approximately 6% of buildings in Christchurch CBD were observed to have suffered some form of serious pounding damage. Almost all of this pounding damage occurred in masonry buildings, further highlighting their vulnerability to this phenomenon. Modern buildings were found to be vulnerable to pounding damage where overly stiff and strong ‘flashing’ components were installed in existing building separations. Soil variability is identified as a key aspect that amplifies the relative movement of buildings, and hence increases the likelihood of pounding damage. Pounding damage in bridges was found to be relatively minor and infrequent in the Christchurch earthquake.
This paper describes the performance of (or damage to) ceilings in buildings during the 22nd February 2011 Christchurch earthquake and the subsequent aftershocks. In buildings that suffered severe structural damage, ceilings and other non-structural components (rather expectedly) failed, but even in buildings with little damage to their structural systems, ceilings were found to be severely damaged. The extent of ceiling damage, where the ceilings were subject to severe shaking, depended on the type of the ceiling system, the size and weight of the ceilings and the interaction of ceilings with other elements. The varieties and extent of observed ceiling damage are discussed in this paper with the help of photographs taken after the earthquake.
Site of industry representative organisations provides a one-stop portal where Cantabrians can research and engage local reconstruction professionals from plumbers and electricians to builders and civil contractors. Includes advice and tips.
A photograph of emergency management personnel working in the Christchurch Art Gallery.
A photograph of emergency management personnel working in the Christchurch Art Gallery.
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Heart-shaped notes on the fence of Burwood Primary School. The notes express appreciation for the efforts of the civil defence, fire service, volunteers and council workers from the students of Burwood Primary.
Heart-shaped notes on the fence of Burwood Primary School. The notes express appreciation for the efforts of the civil defence, fire service, volunteers and council workers from the students of Burwood Primary.
Heart-shaped notes on the fence of Burwood Primary School. The notes express appreciation for the efforts of the civil defence, fire service, volunteers and council workers from the students of Burwood Primary.
A video about the work which is being conducted in the Christchurch Red Zone in the weeks after the 22 February 2011 earthquake. Members of the New Zealand Army and Civil Defence are working to secure business premises by boarding up broken windows and doors. The video also includes footage of the damage to the Fisher's Building, the Press Building, Ballies Bar, and ChristChurch Cathedral, and many buildings on High Street.
A photograph of the photocopy template for the Christchurch City Council's yellow sticker. The sticker was used by the Civil Defence after the 2010 and 2011 earthquakes to indicate that a building had been inspected and that structural damage or other safety hazards had been found. The sticker states that there should be no entry to the building, 'except on essential business'. It also states that 'earthquake aftershocks present danger' and that people who enter must do so at their own risk.
A photograph of a make-shift toilet in the Christchurch Art Gallery. A sign behind it reads, "Portaloos Department. We know that 80,000 people need loos. We have 900-1800 available or coming, We don't need to be told people need loos. Thank you. We're number one with your number twos!". Signs below this read, "Toilet Occupied", "Toilet Vacant" and, "In Tray". The Art Gallery was used as the temporary headquarters for Civil Defence after the 22 February 2011 earthquake.
University of Canterbury ICT staff members prepare to be escorted to buildings by Civil Defence members in order to retrieve computers from offices. The photographer comments, "ICT staff head out to retrieve computers from buildings".
A photograph of emergency management personnel in the foyer of the Christchurch Art Gallery.
Page 18 of Section A of the Christchurch Press, published on Wednesday 6 April 2011.
Misko Cubrinovski, Civil Engineer, photographed with liquefaction and lateral spreading on Oxford Terrace. Misko's area is geotechnical earthquake engineering and foundation engineering, and he will feature in a UC in the News pull out supplement inThe Press.
The Lyttelton Harbour Information Centre's "Community Earthquake Update" bulletin, published on Friday 1 July 2011.
University of Canterbury staff members prepare to be escorted to their buildings by Civil Defence members in order to retrieve essential items from their offices. The photographer comments, "Susan Tull (E-learning), Leigh Davidson (MBA administrator), Bob Reed (Economics)".