A multi-disciplinary geo-structural-environmental engineering project funded by the Ministry of Business Innovation and Employment (MBIE) is being carried out at the University of Canterbury. The project aims at developing an eco-friendly seismic isolation foundation system which will improve the seismic performance of medium-density low-rise buildings. Such system is characterized by two main elements: 1) granulated scrap rubber mixed with gravelly soils to be placed beneath the structure, with the goal damping part of the seismic energy before it reaches the superstructure; and 2) a basement raft made of steel-fibre reinforced rubberised concrete (SFRRuC) to enhance the flexibility and toughness of the foundation, looking at better accommodating the displacement demand. In this paper, the main objectives, scope and methodology of the project will be briefly described. A literature review of the engineering properties of steel-fibre reinforced rubberised concrete (RuC) will be presented. Then, preliminary results on concrete mixes with different rubber and steel fibres content will be exhibited.
There is an increasing recognition that the seismic performance of buildings will be affected by the behaviour of both structural and non-structural elements. In light of this, work has been progressing at the University of Canterbury to develop guidelines for the seismic assessment of commercial glazing systems. This paper reviews the seismic assessment guidelines prescribed in Section C10 of the MBIE building assessment guidelines. Subsequently, the C10 approach is used to assess the drift capacity of a number of glazing units recently tested at the University of Canterbury. Comparing the predicted and observed drift capacities, it would appear that the C10 guidelines may lead to nonconservative estimates of drift capacity. Furthermore, the experimental results indicate that watertightness may be lost at very low drift demands, suggesting that guidance for the assessment of serviceability performance would also be beneficial. As such, it is proposed that improved guidance be provided to assist engineers in considering the possible impact that glazing could have on the structural response of a building in a large earthquake.
Low Damage Seismic Design (LDSD) guidance material being developed by Engineering NZ is considering a design drift limit for multi-storey buildings of 0.5% at a new damage control limit state (DCLS). The impact of this new design requirement on the expected annual loss due to repair costs is investigated for a four-storey office building with reinforced concrete walls located in Christchurch. The LDSD guidance material aims to reduce the expected annual loss of complying buildings to below 0.1% of building replacement cost. The research tested this expectation. Losses were estimated in accordance with FEMA P58, using building responses from non-linear time history analyses (performed with OpenSees using lumped plasticity models). The equivalent static method, in line with NZS 1170.5 and NZS 3101, was used to design the building to LDSD specifications, representing a future state-of-practice design. The building designed to low-damage specification returned an expected annual loss of 0.10%, and the building designed conventionally returned an expected annual loss of 0.13%. Limitations with the NZS 3101 method for determining wall stiffness were identified, and a different method acknowledging the relationship between strength and stiffness was used to redesign the building. Along with improving this design assumption, the study finds that LDSD design criteria could be an effective way of limiting damage and losses.
Photograph captioned by Fairfax, "The Provincial Hotel Building getting loose material removed after becoming unstable due to the September earthquake".
Photograph captioned by Fairfax, "The Provincial Hotel Building getting loose material removed after becoming unstable due to the September earthquake".
A photograph captioned by BeckerFraserPhotos, "A crane lifting roof material off a demolition building at 705 Colombo Street".
Photograph captioned by Fairfax, "The Provincial Hotel Building getting loose material removed after becoming unstable due to the September earthquake".
Photograph captioned by Fairfax, "Post-earthquake demolition. Materials from a building on St Asaph Street still waiting to be cleared".
Photograph captioned by BeckerFraserPhotos, "Material stripped out of the building at the Haldenstein's/Unlimited Paenga School site, High Street".
A crane lifting material off the roof the damaged Cathedral of the Blessed Sacrament on Barbadoes Street.
Benches made out of recycled material from demolished buildings. These benches will serve as seats for Gap Filler's temporary cinema, 'The Night Club'.
A photograph of salvaged stained-glass windows from the demolished Warners Hotel.
Relates to the three new categories for residential foundation design that have been developed and will be required for repairing and rebuilding homes in Canterbury following the earthquakes of 2010 and 2011. The 'zones' referred to in the cartoon are the colours designated to different degrees of damage to particular areas or buildings in Christchurch after the earthquakes. Quantity: 1 digital cartoon(s).
A photograph captioned by BeckerFraserPhotos, "Materials salvaged from Our City, O-Tautahi on pallets out front".
A volunteer constructs benches out of recycled material from demolished building. These benches will serve as seats for Gap Filler's temporary cinema, 'The Night Club'.
Damage to the side of the Cathedral of the Blessed Sacrament on Barbadoes Street. Above, a crane is lifting material off the roof.
An artwork in the walls of the Gap Filler Headquarters office building in Sydenham. The wall is made out of perspex which reveals recycled materials underneath.
An artwork in the walls of the Gap Filler Headquarters office building in Sydenham. The wall is made out of perspex which reveals recycled materials underneath.
Photograph captioned by BeckerFraserPhotos, "Container shops being constructed in Cashel Mall on the Whitcoulls site".
Unreinforced masonry (URM) buildings have repeatedly been shown to perform poorly in large magnitude earthquakes, with both New Zealand and Australia having a history of past earthquakes that have resulted in fatalities due to collapsed URM buildings. A comparison is presented here of the URM building stock and the seismic vulnerability of Christchurch and Adelaide in order to demonstrate the relevance to Australian cities of observations in Christchurch resulting from the 2010/2011 Canterbury earthquake swarm. It is shown that the materials, architecture and hence earthquake strength of URM buildings in both countries is comparable and that Adelaide and other cities of Australia have seismic vulnerability sufficient to cause major damage to their URM buildings should a design level earthquake occur. Such an earthquake is expected to cause major building damage, and fatalities should be expected.
A photograph of a mural on a wall in the former site of a building on Norwich Quay in Lyttelton. Construction material has been laid up against the mural.
A photograph of a room in the Diabetes Centre with building materials in the corner. Plastic sheeting has been placed over the carpet and has been used to create a temporary wall on the right.
Photograph captioned by BeckerFraserPhotos, "Looking along Gloucester Street towards the Marque Hotel with the Novotel on the right. Demolition material is the Coachman".
Photograph captioned by BeckerFraserPhotos, "Cashel Mall looking towards the Whitcoulls site and the BNZ in the distance behind the centre tree".
Semi-circular quilt made from cotton, silk and bandage material to commemorate the 22 February 2011 earthquake. The quilt references Christchurch landscape features, buildings and soil profiles and displays 185 sewn crosses, eight facial profiles and a Harakeke (flax).
Following the devastating 1931 Hawke's Bay earthquake, buildings in Napier and surrounding areas in the Hawke's Bay region were rebuilt in a comparatively homogenous structural and architectural style comprising the region's famous Art Deco stock. These interwar buildings are most often composed of reinforced concrete two-way space frames, and although they have comparatively ductile detailing for their date of construction, are often expected to be brittle, earthquake-prone buildings in preliminary seismic assessments. Furthermore, the likelihood of global collapse of an RC building during a design-level earthquake became an issue warranting particular attention following the collapse of multiple RC buildings in the February 22, 2011 Christchurch earthquake. Those who value the architectural heritage and future use of these iconic Art Deco buildings - including building owners, tenants, and city officials, among others - must consider how they can be best preserved and utilized functionally given the especially pressing implications of relevant safety, regulatory, and economic factors. This study was intended to provide information on the seismic hazard, geometric weaknesses, collapse hazards, material properties, structural detailing, empirically based vulnerability, and recommended analysis approaches particular to Art Deco buildings in Hawke's Bay as a resource for professional structural engineers tasked with seismic assessments and retrofit designs for these buildings. The observed satisfactory performance of similar low-rise, ostensibly brittle RC buildings in other earthquakes and the examination of the structural redundancy and expected column drift capacities in these buildings, led to the conclusion that the seismic capacity of these buildings is generally underrated in simple, force-based assessments.
The perspex wall of the 10 square metre office building viewed from the inside. Volunteers have begun to fill the wall with recycled materials which will be sealed inside with another sheet of perspex.
A photograph of the street art in front of St Barnabas Church on Fendalton Road. The message, "Outrageous", has been constructed from fabric and other materials on the wire fences in front of the building.
A photograph of a mural on a wall in the former site of a building on Norwich Quay in Lyttelton. Sections of reinforcing steel and other construction material have been laid up against the mural.
A photograph of the street art in front of St Barnabas Church on Fendalton Road. The message, "Outrageous", has been constructed from fabric and other materials on the wire fences in front of the building.