A Christchurch community board member says government changes to a scheme helping owners of earthquake-damaged homes shows they don't understand what claimants are dealing with. Community board member Ali Jones spoke to Guyon Espiner.
A new exhibition showcases relics found underneath Christchurch's Cathedral of the Blessed Sacrament, which was badly damaged in the Christchurch earthquakes.
Christchurch's Cardboard Cathedral was designed as a temporary structure to fill the void left by the damage caused to Christ Church Cathedral in the 2011 earthquake.
Reinforced concrete (RC) frame buildings designed according to modern design standards achieved life-safety objectives during the Canterbury earthquakes in 2010-11 and the Kaikōura earthquake in 2016. These buildings formed ductile plastic hinges as intended and partial or total building collapse was prevented. However, despite the fact that the damage level of these buildings was relatively low to moderate, over 60% of multi-storey RC buildings in the Christchurch central business district were demolished due to insufficient insurance coverage and significant uncertainty in the residual capacity and repairability of those buildings. This observation emphasized an imperative need to improve understanding in evaluating the post-earthquake performance of earthquake-damaged buildings and to develop relevant post-earthquake assessment guidelines. This thesis focuses on improving the understanding of the residual capacity and repairability of RC frame buildings. A large-scale five-storey RC moment-resisting frame building was tested to investigate the behaviour of earthquake-damaged and repaired buildings. The original test building was tested with four ground motions, including two repeated design-level ground motions. Subsequently, the test building was repaired using epoxy injection and mortar patching and re-tested with three ground motions. The test building was assessed using key concepts of the ATC-145 post-earthquake assessment guideline to validate its assessment procedures and highlight potential limitations. Numerical models were developed to simulate the peak storey drift demand and identify damage locations. Additionally, fatigue assessment of steel reinforcement was conducted using methodologies as per ATC-145. The residual capacity of earthquake-strained steel reinforcement was experimentally investigated in terms of the residual fatigue capacity and the residual ultimate strain capacity. In addition to studying the fatigue capacity of steel reinforcement, the fatigue damage demand was estimated using 972 ground motion records. The deformation limit of RC beams and columns for damage control was explored to achieve a low likelihood of requiring performance-critical repair. A frame component test database was developed, and the deformation capacity at the initiation of lateral strength loss was examined in terms of the chord rotation, plastic rotation and curvature ductility capacity. Furthermore, the proposed curvature ductility capacity was discussed with the current design curvature ductility limits as per NZS 3101:2006
Residents of Christchurch's coastal suburbs around New Brighton are being promised they won't have to wait another decade for an urgently needed new bridge. The existing one is a critical emergency escape route but is almost 100 years old and suffered significant damage in the 2011 earthquake. And as Timothy Brown reports, plans for an upgrade are grinding slowly ahead.
The research presented in this thesis investigated the environmental impacts of structural design decisions across the life of buildings located in seismic regions. In particular, the impacts of expected earthquake damage were incorporated into a traditional life cycle assessment (LCA) using a probabilistic method, and links between sustainable and resilient design were established for a range of case-study buildings designed for different seismic performance objectives. These links were quantified using a metric herein referred to as the seismic carbon risk, which represents the expected environmental impacts and resource use indicators associated with earthquake damage during buildings’ life. The research was broken into three distinct parts: (1) a city-level evaluation of the environmental impacts of demolitions following the 2010/2011 Canterbury earthquake sequence in New Zealand, (2) the development of a probabilistic framework to incorporate earthquake damage into LCA, and (3) using case-study buildings to establish links between sustainable and resilient design. The first phase of the research focused on the environmental impacts of demolitions in Christchurch, New Zealand following the 2010/2011 Canterbury Earthquake Sequence. This large case study was used to investigate the environmental impact of the demolition of concrete buildings considering the embodied carbon and waste stream distribution. The embodied carbon was considered here as kilograms of CO2 equivalent that occurs on production, construction, and waste management stage. The results clearly demonstrated the significant environmental impacts that can result from moderate and large earthquakes in urban areas, and the importance of including environmental considerations when making post-earthquake demolition decisions. The next phase of the work introduced a framework for incorporating the impacts of expected earthquake damage based on a probabilistic approach into traditional LCA to allow for a comparison of seismic design decisions using a carbon lens. Here, in addition to initial construction impacts, the seismic carbon risk was quantified, including the impacts of seismic repair activities and total loss scenarios assuming reconstruction in case of non-reparability. A process-based LCA was performed to obtain the environmental consequence functions associated with structural and non-structural repair activities for multiple environmental indicators. In the final phase of the work, multiple case-study buildings were used to investigate the seismic consequences of different structural design decisions for buildings in seismic regions. Here, two case-study buildings were designed to multiple performance objectives, and the upfront carbon costs, and well as the seismic carbon risk across the building life were compared. The buildings were evaluated using the framework established in phase 2, and the results demonstrated that the seismic carbon risk can significantly be reduced with only minimal changes to the upfront carbon for buildings designed for a higher base shear or with seismic protective systems. This provided valuable insight into the links between resilient and sustainable design decisions. Finally, the results and observations from the work across the three phases of research described above were used to inform a discussion on important assumptions and topics that need to be considered when quantifying the environmental impacts of earthquake damage on buildings. These include: selection of a non-repairable threshold (e.g. a value beyond which a building would be demolished rather than repaired), the time value of carbon (e.g. when in the building life the carbon is released), the changing carbon intensity of structural materials over time, and the consideration of deterministic vs. probabilistic results. Each of these topics was explored in some detail to provide a clear pathway for future work in this area
Recent seismic events, such as the 2010-2011 Canterbury earthquakes and the 2016 Kaikōura earthquakes, have shed light on issues with the seismic performance of glazing systems. This is attributed to the limited amount of research and consideration of glazing systems in design and assessments. Previous research and evidence from post-earthquake reconnaissance have shown that glazing systems pose a hazard due to falling glass. As such, it is vital to ensure that glazing systems are designed with the necessary levels of seismic performance. Furthermore, the post-earthquake repair of glass facades can be costly and time-consuming. Some previous research has been conducted to highlight the seismic performance and fragility of glazing systems. However, most prior research only focussed on life-safety issues of glazing systems and rarely on the serviceability of glazing systems. The serviceability of glazing systems, such as water-tightness, is a vital aspect of glazing systems as a low serviceability capacity will increase the likelihood of further damage which will increase economic losses. This is the aim of this research, to provide insight towards the seismic performance of glazing systems considering both the serviceability and ultimate limit state by generating insight into the behaviour of glazing systems and developing tools for the consideration of glazing systems in design and assessment. This will allow a value proposition for seismic detailing of glazing to be evaluated. In order to provide insight into the behaviour of glazing systems and a means for evaluating their seismic performance, this research firstly develops an applicable experimental testing procedure that allows for serviceability limit state tests on glazing units. This experimental testing procedure is used to obtain data on the vulnerability of general New Zealand glazing systems’ performance, specifically unitised glazing systems that are commonly used as commercial shopfront glazing system types. These glazing systems typically realised using aluminium framing with gaskets connecting the frame to the glass. After the experimental testing, numerical analyses calibrated to the experimental testing results are conducted to enable robust analyses of glazing systems’ fragility. Finally, a value proposition for glazing systems with seismic detailing is made by comparing the performance of glazing systems with seismic detailing and conventional glazing systems. This comparison is done using the PEER-PBEE method and the economic implications of each glazing system is shown. Suggestions for designers and stakeholders aimed at reducing costs related to the seismic performance of glazing systems is also shown. Using the novel experimental method developed in this research, three different full-scale glazing systems were tested. A total of 10 unitised glazing specimens were tested; three with standard detailing, three with seismic detailing and four that were structurally glazed. These tests evaluated three damage states (DS): loss of water-tightness (DS1), gasket damage (DS2), and glass or framing failure (DS3). The experimental method that was adopted is considered to be more desirable than the optional procedures set out in New Zealand glazing standards. The method does not require high-speed testing equipment and is easy to replicate by the industry. The test results show that water-tightness was lost at low drift levels, with the first leakage occurring at just 0.15% drift for one specimen, while a standard glazing system had a median drift capacity of 0.35%. In contrast, seismic glazing systems detailed to better accommodate in-plane movements, demonstrated a significantly higher median drift capacity of 1.88%. The numerical approach proposed in this research has shown that it is possible to numerically model the glazing-gasket interaction to conservatively predict the water-leakage drift (damage state 1). The modelling approach still needs further development if it were to be used for damage states DS2 and DS3. The last part of the research considered the value proposition for seismic glazing systems. This was achieved by applying the FEMA P-58 performance assessment framework to a number of case study buldings that are typical of New Zealand design. The results suggest that it may not be economically worthwhile to use well-detailed seismic glazing systems despite the considerably larger drift capacity they possess relative to standard systems. However, as the cost of seismic glazing systems reduces, and more information on repair costs for different damage states is obtained, the value proposition may change.
Film and TV reviewer Perlina Lau joins Kathryn to talk about murder mystery The Perfect Couple (Netflix), starring Nicole Kidman and Eve Hewson. She'll also talk about documentary Maurice and I (cinemas) that celebrates Sir Miles Warren and Maurice Mahoney's hugely influential architectural partnership, and impact the Christchurch earthquakes had on their legacy. And A Very Royal Scandal (Prime Video) is the second recent production that goes behind the scenes of the damaging interview Prince Andrew gave over his friendship with Jeffrey Epstein. Perlina Lau is co-host of RNZ's Culture 101 programme.
Gulls are well known for swooping in and flogging food off your plate or picnic and now they are making a complete menace of themselves in Christchurch's New Regent street. Local businesses are being over-run by the red and black-billed gulls that are nesting on the rooves of buildings along the street, swooping and pooping all over the place. It's not the first time they've invaded, they started breeding in 2019 in an earthquake damaged building on the corner of Armagh and New Regent streets. The problem is both the red and black-billed gulls are protected. Casey Alderson from Belle Cafe spoke to Lisa Owen.
Observations in major earthquakes have shown that rockable structures suffered less to no damage. During rocking, that is, partial and temporary footing separations, the influx of seismic energy is interrupted and thus the impact of the base excitation is reduced. Rocking causes the structure to deform more rigid like. Consequently, the structure experiences less deformation along the height and thus a lower damage potential. Although many researchers have studied the influence of rockable footings, most of these are either analytical or numerical, and only a very few structures have been built with rockable footings worldwide, for example, the chimney at Christchurch Airport and the South Rangitikei Viaduct in New Zealand. Despite these studies, a thorough and understanding is not yet available, especially with respect to experimental validations. This work is the first to investigate the rocking behaviour of bridges with different slenderness using large‐scale shake table experiments. To limit the number of influence factors, a stiff footing support and the same fixed‐base fundamental frequency of the bridges were assumed. The result shows that the girder displacement and the footing rotation of the tall bridge do not always move in phase, which cannot be observed in the short bridge. The results demonstrate the important role of slenderness in the overall responses of rockable bridges. This behaviour cannot be observed in bridges with a commonly assumed fixed base since the slenderness effect cannot be activated
Natural disasters are often unpredictable and are happening frequently. Some natural disasters cause damage to communities, resulting in displaced individuals. Due to this there is a need for shelter, however, there are many unknown factors. These include unknown demographics, a strain on time, cost, and resources, and the unknown location. This study begins by identifying a lack of identity and personality in existing post-disaster shelter designs, including the example of Linwood Park from the Christchurch 2011 earthquake. Further research shows the lack of personalisation within shelters, along with addressing key requirements needed for shelters. While providing the basic needs is essential, this thesis also addresses how personalisation can impact a space. Taking bach architecture as a driver for a basic, yet unique approach to temporary accommodation, Lake Clearwater Settlement was used as a case study. Through surveys, interviews, and a reflective design process, the importance of embracing identity emerges as a key element in fostering dignity, livelihood, and a sense of self in displaced individuals. This thesis explores innovative approaches to post-disaster shelter design with a focus on accommodating the unique needs and individuality of displaced individuals. From challenging conventional shelter concepts to embracing self-design and community involvement, the research addresses the question of how interior and exterior features can cater to the diverse requirements of those affected by natural disasters.
- The Avon-Ōtākaro Redzone is an 11 kilometer stretch of land along the Avon-Ōtākaro River in Christchurch. - This project focused on the creation of a publicly available biodiversity map of the AvonŌtākaro River Corridor, a project undertaken as part of the ecological restoration of the Christchurch redzone. - This project originated from the Christchurch 2010-2011 earthquake sequence which saw liquefaction damage along 11km of the Avon River. Under guidance from The Nature Lab & Ōtākaro Living Laboratory, and various other experts, the primary research objective was to map historical biodiversity, identify hotspots, and assess areas for potential revegetation. - The data collected came from historical black maps, current iNaturalist data, and soil classification information. - The findings show that, pre-colonialism, the area was composed of herbaceous areas, wetlands, native shrubland, and tussock land, with key plants such as river, fern, tutu, and cabbage trees. - The post-earthquake analysis shows a transition from a residential area to patchy grasslands and swampy areas. - The findings also showed a strong relationship between historic sites and soil classifications, providing knowledge for past and future vegetation patterns and spread. - This map will be a valuable resource for conservation efforts and public engagement as the area transitions into a blue-green corridor.