The M7.1 Darfield earthquake shook the town of Christchurch (New Zealand) in the early morning on Saturday 4th September 2010 and caused damage to a number of heritage unreinforced masonry buildings. No fatalities were reported directly linked to the earthquake, but the damage to important heritage buildings was the most extensive to have occurred since the 1931 Hawke‟s Bay earthquake. In general, the nature of damage was consistent with observations previously made on the seismic performance of unreinforced masonry buildings in large earthquakes, with aspects such as toppled chimneys and parapets, failure of gables and poorly secured face-loaded walls, and in-plane damage to masonry frames all being extensively documented. This report on the performance of the unreinforced masonry buildings in the 2010 Darfield earthquake provides details on typical building characteristics, a review of damage statistics obtained by interrogating the building assessment database that was compiled in association with post-earthquake building inspections, and a review of the characteristic failure modes that were observed.
A photograph of an earthquake-damaged building on Manchester Street. The corner of the building has cracks running through the masonry.
A photograph of the earthquake damage to the Fisher's Building on the corner of High and Hereford Streets. Large sections of the top storey have collapsed, the masonry spilling onto the footpath and damaging the awning.
Damage to the masonry of an old building on Ferry Road in Woolson.
Damage to the masonry of an old building on Ferry Road in Woolson.
A photograph of an earthquake-damaged building on the corner of Welles and Manchester Streets. Masonry from the top floor of the building has come away and windows have been broken.
A photograph of the badly damaged Canterbury Provincial Chambers on Durham Street. The roof and upper walls of the Stone Chamber have collapsed, the masonry falling onto the footpath below.
Damaged masonry at the top of the former Canterbury Jockey Club building on Oxford Terrace.
A photograph of emergency management personnel crossing the intersection of High, Colombo, and Hereford Streets. In the background is the earthquake-damaged Fisher's Building. Large sections of the top storey have collapsed, the masonry spilling onto the footpath and damaging the awning.
Martin van Beynen, a reporter for The Press newspaper, photographing damage to Wave House (Winnie Bagoes Pizza Bar). Masonry from the building has collapsed onto several parked cars.
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/
A photograph of the earthquake damage to the Registry Building on the corner of Montreal and Worcester Streets. Masonry around the gable has collapsed onto the footpath below. Steel bracing has been used to hold up the remaining masonry. Wire fencing has been placed around the building as a cordon.
A photograph of the earthquake damage to the Registry Building on the corner of Montreal and Worcester Streets. Masonry around the gable has collapsed onto the footpath below. Steel bracing has been used to hold up the remaining masonry. Wire fencing has been placed around the building as a cordon.
A photograph of the earthquake damage to the Canterbury Provincial Chambers on Durham Street. The top of the chamber has crumbled, and the masonry has fallen onto the footpath. Scaffolding which was erected after the 4 September 2010 earthquake has also fallen.
A photograph of the earthquake damage to the Canterbury Provincial Chambers on Durham Street. The top of the chamber has crumbled, and the masonry has fallen onto the footpath. Scaffolding which was erected after the 4 September 2010 earthquake has also fallen.
The sequence of earthquakes that has greatly affected Christchurch and Canterbury since September 2010 has again demonstrated the need for seismic retrofit of heritage unreinforced masonry buildings. Commencing in April 2011, the damage to unreinforced stone masonry buildings in Christchurch was assessed and recorded with the primary objective being to document the seismic performance of these structures, recognising that they constitute an important component of New Zealand’s heritage architecture. A damage statistics database was compiled by combining the results of safety evaluation placarding and post-earthquake inspections, and it was determined that the damage observed was consistent with observations previously made on the seismic performance of stone masonry structures in large earthquakes. Details are also given on typical building characteristics and on failure modes observed. Suggestions on appropriate seismic retrofit and remediation techniques are presented, in relation also to strengthening interventions that are typical for similar unreinforced stone masonry structures in Europe.
A photograph of earthquake damage to the Canterbury Provincial Chambers Buildings, taken from Oxford Terrace, across the Avon River. One of the chimneys has fallen onto the roof, knocking off tiles and pieces of masonry.
A photograph of the earthquake damage to The Press building in Cathedral Square. The top storey of the building has collapsed into the storey below, some of the masonry falling onto the pavement below. Wire fencing has been placed around the building as a cordon.
A photograph of earthquake damage to the Cranmer Courts on the corner of Kilmore and Montreal Streets. Masonry and other rubble is sitting on the footpath in front. Wire fencing has been placed around the building as a cordon.
A photograph of the earthquake damage to the Cranmer Courts on the corner of Montreal and Kilmore Streets. A large section of the building has crumbled, masonry spilling onto the footpath below. Wire fencing has been placed around the building as a cordon.
A photograph of the earthquake damage to the Cranmer Courts on the corner of Montreal and Kilmore Streets. A large section of the building has crumbled, masonry spilling onto the footpath below. Wire fencing has been placed around the building as a cordon.
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.
Damage to the Community of the Sacred Name building on Barbadoes Street. Masonry from one of the building's gables has collapsed onto the footpath.
A photograph of the earthquake-damaged Canterbury Provincial Chambers on Durham Street. The roof and upper walls of the Stone Chamber have collapsed, the masonry falling onto the footpath below. The building has been cordoned off with wire fencing.
A photograph of the earthquake-damaged Canterbury Provincial Chambers on Durham Street. The roof and upper walls of the Stone Chamber have collapsed, the masonry falling onto the footpath below. The building has been cordoned off with wire fencing.
A photograph of the earthquake damage to the old Registry Building on the corner of Worcester and Montreal Streets. The masonry of the Worcester Street gable has crumbled and is lying on the street in front. Wire fencing has been used to cordon off the building.
A photograph of the earthquake damage to the Canterbury Provincial Chambers Building on Durham Street. Large sections of the masonry have collapsed, spilling onto the road. Wire fencing has been placed around the building as a cordon. Scaffolding erected up the side has collapsed.
A photograph of the earthquake damage to the Canterbury Provincial Chambers Building on Durham Street. Large sections of the masonry have collapsed, spilling onto the road. Wire fencing has been placed around the building as a cordon. Scaffolding erected up the side has collapsed.
A photograph of the earthquake-damaged Oxford Terrace Baptist Church. Steels bracing has been used to stabilise the front of the building. Crumbled masonry and other rubble is still lying in front. Wire fences have been placed around the building site as a cordon.
A photograph of the earthquake-damaged Oxford Terrace Baptist Church. Steels bracing has been used to stabilise the front of the building. Crumbled masonry and other rubble is still lying in front. Wire fences have been placed around the building site as a cordon.