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.
Photograph captioned by Fairfax, "2010 Canterbury Earthquake. Workers apply steel framing to protect the historic building now the 'Octagon' restaurant on the corner of Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Major earthquake hits Christchurch. A building inspector puts a yellow ticket (restricted use) on the Octagon restaurant on corner of Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Major earthquake hits Christchurch. A building inspector puts a yellow ticket (restricted use) on the Octagon restaurant on corner of Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Police search a building on the corner of St Asaph Street and Barbadoes Street, after reports of a person in the wreckage following Canterbury's earthquake".
Photograph captioned by Fairfax, "Aftermath of the earthquake in Christchurch, where the clean-up has begun. Historic buildings around Christchurch received varying degrees of damage. Canterbury Museum seems unscathed".
Photograph captioned by Fairfax, "Owners of The Octagon hang models to decorate the structures holding up the tower of the building after earthquake damage. Chris Stead from Theme Pro".
Photograph captioned by Fairfax, "Major earthquake hits Christchurch. A building inspector puts a yellow ticket (restricted use) on the Octagon restaurant on corner of Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Earthquake hits Christchurch. Damage to buildings after the 7.1 earthquake which hit Christchurch in the very early hours. Corner Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Major earthquake hits Christchurch. A building inspector puts a yellow ticket (restricted use) on the Octagon restaurant on corner of Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Earthquake hits Christchurch. Damage to buildings after the 7.1 earthquake which hit Christchurch in the very early hours. Corner Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Earthquake hits Christchurch. Damage to buildings after the 7.1 earthquake which hit Christchurch in the very early hours. Corner Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Earthquake hits Christchurch. Damage to buildings after the 7.1 earthquake which hit Christchurch in the very early hours. Corner Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "Earthquake hits Christchurch. Damage to buildings after the 7.1 earthquake which hit Christchurch in the very early hours. Corner Manchester Street and Worcester Street".
Photograph captioned by Fairfax, "The new Christchurch Council building has suffered only cosmetic damage in the September 4th earthquake. Scaffold under a stairwell which is only slightly damaged".
Photograph captioned by Fairfax, "The new Christchurch Council building has suffered only cosmetic damage in the September 4th earthquake. Construction workers are kept busy moving scaffolding and fixtures".
A video of the Christchurch City Council meeting to discuss its consenting process. The meeting was called after the council received a letter from International Accreditation New Zealand (IANZ) on 30 May 2013. The letter states that the Council has until 28 June 2013 to improve its processes or it will be stripped of its accreditation as a building consent authority. The video includes discussion from Councillor Barry Corbett, Acting Building Operations Manager Steve McCarthy, Democracy Services General Manager Peter Mitchell, Councillor Aaron Keown, and Councillor Claudia Reid.
A video of the damage to central Christchurch after the 4 September earthquake. The video includes footage of car sirens going off, earthquake damage to the shops on the corner of Barbadoes Street and Edgeware Road, the Westende Jewellers building on the corner of Worcester and Manchester Streets, the Repertory Theatre on Kilmore Street, the Asko Design Store on Victoria Street, and a building on the corner of Colombo and Byron Streets. It also includes an interview with Christchurch resident Quentin Garlick.
The Royal Commission hearings into the Canterbury earthquake begin in Christchurch today to examine why some of the newer buildings in the city's CBD failed so badly.
Four cartoons in the same frame commenting on news and happenings in the week ending 15 December 2011. The cartoons refer to the expulsion of the controversial Member of Parliament, Brendan Horan, from the New Zealand First Party by its leader, Winston Peters; the stereotyping of New Zealand as being 'Middle Earth' following the filming of 'The Hobbit', punned as 'The Habbit'; the lax attitude to building design and standards, which led to the CTV Building disaster in the Christchurch earthquake; the news about the New Zealand SPCA teaching dogs to drive. Quantity: 1 digital cartoon(s).
The performance of buildings in recent New Zealand earthquakes (Canterbury, Seddon and Kaikōura), delivered stark lessons on seismic resilience. Most of our buildings, with a few notable exceptions, performed as our Codes intended them to, that is, to safeguard people from injury. Many buildings only suffered minor structural damage but were unable to be reused and occupied for significant periods of time due to the damage and failure of non-structural elements. This resulted in substantial economic losses and major disruptions to our businesses and communities. Research has attributed the damage to poor overall design coordination, inadequate or lack of seismic restraints for non structural elements and insufficient clearances between building components to cater for the interaction of non structural elements under seismic actions. Investigations have found a clear connection between the poor performance of non-structural elements and the issues causing pain in the industry (procurement methods, risk aversion, the lack of clear understanding of design and inspection responsibility and the need for better alignment of the design codes to enable a consistent integrated design approach). The challenge to improve the seismic performance of non structural elements in New Zealand is a complex one that cuts across a diverse construction industry. Adopting the key steps as recommended in this paper is expected to have significant co-benefits to the New Zealand construction industry, with improvements in productivity alongside reductions in costs and waste, as the rework which plagues the industry decreases.
A photograph of a window of the IRD building. Directions to a rear entrance have been written on the window.
Light timber framed (LTF) structures provide a cost-effective and structurally efficient solution for low-rise residential buildings. This paper studies seismic performance of single-storey LTF buildings sheathed by gypsum-plasterboards (GPBs) that are a typical lining product in New Zealand houses. Compared with wood-based structural panels, GPBs tend to be more susceptible to damage when they are used in bracing walls to resist earthquake loads. This study aims to provide insights on how the bracing wall irregularity allowed by the current New Zealand standard NZS 3604 and the in-plane rigidity of ceiling diaphragms affect the overall seismic performance of these GPB-braced LTF buildings. Nonlinear time-history analyses were conducted on a series of single-storey baseline buildings with different levels of bracing wall irregularities and ceiling diaphragm rigidity. The results showed significant torsional effect caused by the eccentric bracing wall layout with semi-rigid/rigid ceiling diaphragms. On average, bracing wall drift demand caused by the extreme bracing wall irregularities was three times of that in the regular bracing wall layout under the rigid diaphragm assumption. This finding agreed well with the house survey after the 2011 Canterbury Earthquake in which significantly more damage was observed in the houses with irregular bracing wall layouts and relatively rigid diaphragms. Therefore, it is recommended to limit the level of bracing wall eccentricity and ensure the sufficiently rigid diaphragms to avoid excessive damage in these LTF buildings in future events.
One landscape colour digital photograph taken on 25 February 2011 showing the damage to the former Anglican Vicarage on Ripon Street Lyttelton. Taken from the footpath. Architect The sense of loss felt when confronted with the collapse or demolition of an historic building is compounded when that building is also a home. While the community sees...
A video showing part of the demolition of the Ozone Hotel in New Brighton. Steve Taylor comments "She put up a good fight. The Ozone in New Brighton was damaged in the February earthquake in Christchurch, New Zealand. Here is the main corner of the structure being, as they say, deconstructed. At the end there is a reverent bow by the excavator. Just before this the claw had caught on the floor/ceiling and the whole building shook from side to side, but it still stayed in place."
A view down New Regent Street. Several of the buildings have had their verandahs propped with steel poles, and scaffolding has been constructed on their facades.
A digitally manipulated photograph of a building on Poplar Lane. The photographer comments, "I felt that this building had a real Italian feel about it. It is actually in Christchurch, New Zealand. It appears on the list to be partially demolished after the Christchurch earthquake, so it might not be around for much longer".
Timber Mill being condemed.
Implementing seismic risk mitigation is a major challenge in many earthquake prone regions. The objective of this research is to investigate how property investment market practices can be used to enhance building owners’ decisions to improve seismic performance of earthquake prone buildings (EPBs). A case study method adopted, revealed the impacts of the property market stakeholders’ practices on seismic retrofit decisions. The findings from this research provide significant new insights on how property market-based incentives such as such as mandatory disclosure of seismic risks in all transactions in the property market, effective awareness seismic risk program and a unified earthquake safety assessment information system, can be used to enhance EPBs owners seismic retrofit decisions. These market-based incentives offer compelling reasons for the different property market stakeholders and the public at large to retain, care, invest, and act responsibly to rehabilitate EPBs. The findings suggest need for stakeholders involved in property investment and retrofit decisions to work together to foster seismic rehabilitation of EPBs.
A PDF copy of The Star newspaper, published on Wednesday 5 December 2012.