A house near the Avon river which has suffered damage. The door and one window have been boarded up.
A damaged residential property has been cordoned off with tape. Piles of brick can be seen around the house.
The homes in the cul-de-sac Seabreeze Close are no more than just three or four years old but the land they were built on liquified during the earthquake and sent masses of mud and silt through the houses.
Minor damage to tiles over the window of a two-storey house. A crane can be seen in the background.
Damaged building and the back of Argosy House, seen from behind cordon fencing. Cracks down the walls are clearly visible.
Damaged building and the back of Argosy House, seen from behind cordon fencing. Cracks down the walls are clearly visible.
Photograph captioned by Fairfax, "Steve Simpson and Janice Hartzer from the EQC inspect a house for earthquake damage at Fairview".
Damaged footpath outside a house in a residential area. Next to the fence is a road cone decorated with coloured tinsel.
A house which has sunk on one side. Damage to the roof can be seen. The property has been taped off.
Damage to a property where the brick wall has crumbled, revealing the internal wooden structure and the inside of the house.
There are hopes an earthquake simulation in Porirua might result in homes being better prepared for a big shake. Houses on Christchurch's Port Hills suffered more damage than houses in other areas during the Canterbury Earthquakes - even though the ground shaking was roughly the same. Now the Earthquake Commission is on a mission to find out why that was - and prevent the same level of damage in a future quake. Checkpoint reporter Logan Church and video journalist Dom Thomas start their report up on a hilly farm above Wellington.
A building on St Asaph Street has been demolished, exposing the interior structure of the adjoining building. The photographer comments, "The building that this one was part of has been demolished and the join looks very much like the exterior walls of an Anglo-Saxon house. It has been exposed due to the demolition of damaged buildings after the Christchurch earthquake".
A photograph of the earthquake damage to the porch of Robin Duff's house at 386 Oxford Terrace. The top half of the far wall has broken loose and is hanging at an angle.
The Canterbury Earthquakes of 2010-2011, in particular the 4th September 2010 Darfield earthquake and the 22nd February 2011 Christchurch earthquake, produced severe and widespread liquefaction in Christchurch and surrounding areas. The scale of the liquefaction was unprecedented, and caused extensive damage to a variety of man-made structures, including residential houses. Around 20,000 residential houses suffered serious damage as a direct result of the effects of liquefaction, and this resulted in approximately 7000 houses in the worst-hit areas being abandoned. Despite the good performance of light timber-framed houses under the inertial loads of the earthquake, these structures could not withstand the large loads and deformations associated with liquefaction, resulting in significant damage. The key structural component of houses subjected to liquefaction effects was found to be their foundations, as these are in direct contact with the ground. The performance of house foundations directly influenced the performance of the structure as a whole. Because of this, and due to the lack of research in this area, it was decided to investigate the performance of houses and in particular their foundations when subjected to the effects of liquefaction. The data from the inspections of approximately 500 houses conducted by a University of Canterbury summer research team following the 4th September 2010 earthquake in the worst-hit areas of Christchurch were analysed to determine the general performance of residential houses when subjected to high liquefaction loads. This was followed by the detailed inspection of around 170 houses with four different foundation types common to Christchurch and New Zealand: Concrete perimeter with short piers constructed to NZS3604, concrete slab-on-grade also to NZS3604, RibRaft slabs designed by Firth Industries and driven pile foundations. With a focus on foundations, floor levels and slopes were measured, and the damage to all areas of the house and property were recorded. Seven invasive inspections were also conducted on houses being demolished, to examine in more detail the deformation modes and the causes of damage in severely affected houses. The simplified modelling of concrete perimeter sections subjected to a variety of liquefaction-related scenarios was also performed, to examine the comparative performance of foundations built in different periods, and the loads generated under various bearing loss and lateral spreading cases. It was found that the level of foundation damage is directly related to the level of liquefaction experienced, and that foundation damage and liquefaction severity in turn influence the performance of the superstructure. Concrete perimeter foundations were found to have performed most poorly, suffering high local floor slopes and being likely to require foundation repairs even when liquefaction was low enough that no surface ejecta was seen. This was due to their weak, flexible foundation structure, which cannot withstand liquefaction loads without deforming. The vulnerability of concrete perimeter foundations was confirmed through modelling. Slab-on-grade foundations performed better, and were unlikely to require repairs at low levels of liquefaction. Ribraft and piled foundations performed the best, with repairs unlikely up to moderate levels of liquefaction. However, all foundation types were susceptible to significant damage at higher levels of liquefaction, with maximum differential settlements of 474mm, 202mm, 182mm and 250mm found for concrete perimeter, slab-on-grade, ribraft and piled foundations respectively when subjected to significant lateral spreading, the most severe loading scenario caused by liquefaction. It was found through the analysis of the data that the type of exterior wall cladding, either heavy or light, and the number of storeys, did not affect the performance of foundations. This was also shown through modelling for concrete perimeter foundations, and is due to the increased foundation strengths provided for heavily cladded and two-storey houses. Heavy roof claddings were found to increase the demands on foundations, worsening their performance. Pre-1930 concrete perimeter foundations were also found to be very vulnerable to damage under liquefaction loads, due to their weak and brittle construction.
A fallen chimney on Derby Street has left a pile of bricks on the roof of the house and damaged the fence.
A damaged property that has been fenced off with tape and road cones. A pile of building rubble sits beside the house.
A house which has sunk on one side. Damage to the roof and garage can be seen. The property has been taped off.
The land and houses close to the Avon River have been badly damaged. Many road and footpaths are covered in silt from liquefaction.
The land and houses close to the Avon River have been badly damaged. Many road and footpaths are covered in silt from liquefaction.
Damage inside a house in St Albans. A television in the living area is showing One News's coverage of the 22 February earthquake.
A house which has suffered miminal damage following the September earthquake. A small section of the roof valley has been covered with tarp.
A digitally manipulated photograph of a letterbox lying on the ground in front of a red-stickered house. The photographer comments, "An abandoned red stickered house just outside the four avenues that surround Christchurch CBD. The letterbox came down when the wall it was attached to collapsed. The occupants would have had strict instructions to stay out as the property is too dangerous to enter in case there is another earthquake or big aftershock".
With many in Christchurch still living in earthquake damaged houses, the cold snap has prompted a call for temporary emergency shelters. Daphne Lewis-Mannix lives in a quake-damaged home in New Brighton. Her power was out last night, and she's been shivering overnight, already sick with a cold before the storm hit.
Photograph captioned by Fairfax, "Nathan Worner with his son James (age 2) outside his earthquake-damaged house. Mr. Worner has become frustrated trying to get EQC to recognise the damage to one the chimneys (covered with blue tarp.) caused by the September 4th Canterbury Earthquake".
Photograph captioned by Fairfax, "Nathan Worner with his son James (age 2) outside his earthquake-damaged house. Mr. Worner has become frustrated trying to get EQC to recognise the damage to one the chimneys (covered with blue tarp.) caused by the September 4th Canterbury Earthquake".
Photograph captioned by Fairfax, "Nathan Worner with his son James (age 2) outside his earthquake-damaged house. Mr. Worner has become frustrated trying to get EQC to recognise the damage to one the chimneys (covered with blue tarp.) caused by the September 4th Canterbury Earthquake".
Photograph captioned by Fairfax, "Prime Minister John Key on his visit to Kaiapoi and Hororata to meet people badly affected and see the damage from the earthquake. Talking to Waimakariri Mayor Ron Keating and National party MP Kate Wilkinson outside a badly damaged house in Kaiapoi".
Photograph captioned by Fairfax, "Emma Goodall from Brooklands who wants to be paid out for the earthquake damage to her two houses".
Photograph captioned by Fairfax, "Workers pull down the two chimneys at Community House in Timaru after they were damaged in the earthquake".
Photograph captioned by Fairfax, "Emma Goodall from Brooklands who wants to be paid out for the earthquake damage to her two houses".