The region in and around Christchurch, encompassing Christchurch city and the Selwyn and Waimakariri districts, contains more than 800 road, rail, and pedestrian bridges. Most of these bridges are reinforced concrete, symmetric, and have small to moderate spans (15–25 m). The 22 February 2011 moment magnitude (Mw) 6.2 Christchurch earthquake induced high levels of localized ground shaking (Bradley and Cubrinovski 2011, page 853 of this issue; Guidotti et al. 2011, page 767 of this issue; Smyrou et al. 2011, page 882 of this issue), with damage to bridges mainly confined to the central and eastern parts of Christchurch. Liquefaction was evident over much of this part of the city, with lateral spreading affecting bridges spanning both the Avon and Heathcote rivers.
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.
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.
Prime Minister John Key and Gerry Brownlee, the Minister of Economic Development, giving a briefing after the 22 February 2011 earthquake.
Evacuees from Christchurch boarding a United States Antarctic Program van to be transported to the C-130 Hercules.
Residents in a hercules being evacuated from Christchurch after the 22 February 2011 earthquake.
Forbes' Store on Norwich Quay with a broken awning and damage visible on the brick walls. Scaffolding placed around the building since the 4 September 2010 earthquake has tumbled during the 22 February 2011 earthquake.
Members of No. 40 Squadron, a transport squadron in the Royal New Zealand Air Force, preparing the Hercules to move people out of Christchurch after the 22 February 2011 earthquake.
People from Christchurch are transported across the tarmac of the Christchurch International Airport in buses. These people were evacuated from Christchurch in the Royal New Zealand Air Force's Hercules after the 22 February 2011 earthquake.
AIRCDRE Howse, CDRE Wayne Burroughs and AVM Peter Stockwell at the Christchurch Earthquake Memorial Service in Hagley Park.
The Royal New Zealand Air Force's C-130 Hercules almost ready to take off. The Hercules was being used to evacuate people from Christchurch after the 22 February 2011 earthquake.
A member of the Royal New Zealand Air Force examining documentation outside the C-130 Hercules at Christchurch airport. The Hercules was being used to evacuate people from Christchurch after the 22 February 2011 earthquake.
The Royal New Zealand Air Force's C-130 Hercules almost ready to take off. The Hercules was being used to evacuate people from Christchurch after the 22 February 2011 earthquake.
People from Christchurch boarding the Royal New Zealand Air Force's Hercules at the Christchurch airport. These people were evacuated from Christchurch after the 22 February 2011 earthquake.
Camera crew filming Prime Minister John Key and Gerry Brownlee, the Minister of Economic Development, giving a briefing after the 22 February 2011 earthquake.
Aerial image of a residential area in Christchurch taken by the Royal New Zealand Air Force for the Earthquake Commission.
Aerial image of a residential area in Christchurch taken by the Royal New Zealand Air Force for the Earthquake Commission.
Soldiers from the New Zealand Army and Singapore Armed Forces walking down the road in Christchurch. To the right, army trucks can be seen.
Photograph captioned by the New Zealand Defence Force, "Chief of Defence Force, Major General Rhys Jones taking off in a Iroquois helicopter as part of an operational tour of earthquake affected areas of Christchurch".
Photograph captioned by the New Zealand Defence Force, "Chief of Defence Force, Major General Rhys Jones on an operational tour of earthquake affected areas of Christchurch".
NZ Army personnel driving an armoured vehicle through the streets of Christchurch after the 22 February 2011 earthquake.
An Air Force craft bringing support to Christchurch after the 22 February 2011 earthquake.
Soldiers from the New Zealand Army guarding a cordon in the central city.
LCPL Ryan Dempsey, from the 3rd Catering and Supply Company, photographed in the NZ Army's decontamination area. The area was set up after the 22 February 2011 earthquake in order to decontaminate equipment used in Operation Christchurch Quake. In the background is a sign reading, 'Contaminated overalls'.
Members of the New Zealand Air Force unloading a generator from a NZ C130 Hercules at the Christchurch Air Movements Terminal. This was the first generators to arrive from Australia to support Operation Christchurch Quake.
PTE Sony Watson, from the 3rd Catering and Supply Company, cleaning a helmet in the decontamination area. The area was set up after the 22 February 2011 earthquake in order to decontaminate equipment used in Operation Christchurch Quake.
A member of Singapore's Air Force laying a wreath in the Christchurch Botanical Gardens. The wreath was laid in memory of those who lost their lives in the Christchurch Earthquake.
Aerial image of Lyttelton taken by the Royal New Zealand Air Force for the Earthquake Commission.
Aerial image of the Christ Church Cathedral in Christchurch taken by the Royal New Zealand Air Force for the Earthquake Commission.
Aerial image of a residential area in Christchurch taken by the Royal New Zealand Air Force for the Earthquake Commission.