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 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.
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 the earthquake damage to the Cranmer Courts on the corner of Montreal and Kilmore Streets. On of the gables has crumbled, the masonry falling to the footpath. A tarpaulin has been used to cover the hole.
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.
Between September 4, 2010 and December 23, 2011, a series of earthquakes struck the South Island of New Zealand including the city of Christchurch producing heavy damage. During the strongest shaking, the unreinforced masonry (URM) building stock in Christchurch was subjected to seismic loading equal to approximately 150-200% of code values. Post-earthquake reconnaissance suggested numerous failures of adhesive anchors used for retrofit connection of roof and floor diaphragms to masonry walls. A team of researchers from the Universities of Auckland (NZ) and Minnesota (USA) conducted a field investigation on the performance of new adhesive anchors installed in existing masonry walls. Variables included adhesive type, anchor diameter, embedment length, anchor inclination, and masonry quality. Buildings were selected that had been slated for demolition but which featured exterior walls that had not been damaged. A summary of the deformation response measured during the field tests are presented. AM - Accepted Manuscript
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.
St Elmo Courts, a NZHPT heritage building on the corner of Hereford and Montreal Streets. The building was severely damaged during the 4 September earthquake, with diagonal cracking between the windows. Scaffolding has been placed around the bottom of the building.
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.
The Catholic Cathedral is classified as a category 1 listed heritage building constructed largely of unreinforced stone masonry, and was significantly damaged in the recent Canterbury earthquakes of 2010 and 2011. In the 2010 event the building presented slight to moderta damage, meanwhile in the 2011 one experienced ground shaking in excess of its capacity leading to block failures and partial collapse of parts of the building, which left the building standing but still posing a significant hazard. In this paper we discuss the approach to develop the earthquake analysis of the building by 3D numerical simulations, and the results are compared/calibrated with the observed damage of the 2010 earthquake. Very accurate records were obtained during both earthquakes due to a record station located least than 80 m of distance from the building and used in the simulations. Moreover it is included in the model the soil structure interaction because it was observed that the ground and foundation played an important role on the seismic behavior of the structure. A very good agreement was found between the real observed damage and the nonlinear dynamic simulations described trough inelastic deformation (cracking) and building´s performance.
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.
During the Christchurch earthquake of February 2011, several midrise buildings of Reinforced Concrete Masonry (RCM) construction achieved performance levels in the range of life safety to near collapse levels. These buildings were subjected to seismic demands higher than the building code requirements of the time and higher than the current New Zealand Loadings Standard (NZS-1170.5:2004). Structural damage to these buildings has been documented and is currently being studied to establish lessons to be learned from their performance and how to incorporate these lessons into future RCM design and construction practices. This paper presents a case study of a six story RCM building deemed to have reached the near collapse performance level. The RCM walls on the 2nd floor failed due to toe crushing reducing the building’s lateral resistance in the east-west direction. A nonlinear dynamic analysis on a 3D model was conducted to simulate the development of the governing failure mechanism. Preliminary analysis results show that the damaged walls were initially under large compression forces from gravity loads which caused increase in their lateral strength and reduced their ductility. After toe crushing failure developed, axial instability of the model was prevented by a redistribution of gravity loads.
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.
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 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.
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.
Following the magnitude 6.3 aftershock in Christchurch, New Zealand, on 22 February 2011, a number of researchers were sent to Christchurch as part of the New Zealand Natural Hazard Research Platform funded “Project Masonry” Recovery Project. Their goal was to document and interpret the damage to the masonry buildings and churches in the region. Approximately 650 unreinforced and retrofitted clay brick masonry buildings in the Christchurch area were surveyed for commonly occurring failure patterns and collapse mechanisms. The entire building stock of Christchurch, and in particular the unreinforced masonry building stock, is similar to that in the rest of New Zealand, Australia, and abroad, so the observations made here are relevant for the entire world.
The city of Christchurch has experienced over 10,000 aftershocks since the 4th of September 2010 earthquake of which approximately 50 have been greater than magnitude 5. The damage caused to URM buildings in Christchurch over this sequence of earthquakes has been well documented. Due to the similarity in age and construction of URM buildings in Adelaide, South Australia and Christchurch (they are sister cities, of similar age and heritage), an investigation was conducted to learn lessons for Adelaide based on the Christchurch experience. To this end, the number of URM buildings in the central business districts of both cities, the extent of seismic strengthening that exists in both cities, and the relative earthquake hazards for both cities were considered. This paper will report on these findings and recommend strategies that the city of Adelaide could consider to significantly reduce the seismic risk posed by URM buildings in future earthquake.
The damaged Cranmer Courts on the corner of Kilmore and Montreal Streets. The corner of the building has crumbled onto the street, which is now littered with broken masonry. Wire fencing placed around the building after the 4 September 2010 earthquake has managed to keep the debris away from the road.
A photograph of the earthquake damage to the Canterbury Provincial Chambers on Durham Street. The top of one of the chambers has crumbled and the masonry has fallen onto the footpath. Scaffolding which was erected after the 4 September 2010 earthquake has also fallen. Wire fences have been placed around the building as a cordon.
A photograph of the earthquake damage to the former Canterbury Public Library on the corner of Hereford Street and Cambridge Terrace. The bricks in the corner of the building have crumbled and masonry can be seen on the footpath below. Wire fences have 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 one of the chambers has crumbled and the masonry has fallen onto the footpath. Scaffolding which was erected after the 4 September 2010 earthquake has also fallen. Wire fences have been placed around the building as a cordon.
A photograph of the earthquake damage to Avonmore House on Hereford Street. Sections of the walls have crumbled, spilling bricks and masonry onto the footpath and street below. Many of the windows have warped, breaking the glass. USAR codes have been spray-painted on one of the columns.
A photograph of the Durham Street Methodist Church blocked off by wire fencing. The tip of the façade is damaged.