Ruth Gardner's Blog 24/09/2011: EQC Evaluation
Articles, UC QuakeStudies
An entry from Ruth Gardner's blog for 24 September 2011 entitled, "EQC Evaluation".
An entry from Ruth Gardner's blog for 24 September 2011 entitled, "EQC Evaluation".
An entry from Ruth Gardner's blog for 24 March 2012 entitled, "Seismic Squeaks".
This paper describes the pounding damage sustained by buildings in the February 2011 Christchurch earthquake. Approximately 6% of buildings in Christchurch CBD were observed to have suffered some form of serious pounding damage. Typical and exceptional examples of building pounding damage are presented and discussed. Almost all building pounding damage occurred in unreinforced masonry buildings, highlighting their vulnerability to this phenomenon. Modern buildings were found to be vulnerable to pounding damage where overly stiff and strong ‘flashing’ components were installed in existing building separations. Soil variability is identified as a key aspect that amplifies the relative movement of buildings, and hence increases the likelihood of pounding damage. Building pounding damage is compared to the predicted critical pounding weaknesses that have been identified in previous analytical research.
This paper describes the pounding damage sustained by buildings in the February 2011 Christchurch earthquake. Approximately 6% of buildings in Christchurch CBD were observed to have suffered some form of serious pounding damage. Typical and exceptional examples of building pounding damage are presented and discussed. Almost all building pounding damage occurred in unreinforced masonry buildings, highlighting their vulnerability to this phenomenon. Modern buildings were found to be vulnerable to pounding damage where overly stiff and strong ‘flashing’ components were installed in existing building separations. Soil variability is identified as a key aspect that amplifies the relative movement of buildings, and hence increases the likelihood of pounding damage. Building pounding damage is compared to the predicted critical pounding weaknesses that have been identified in previous analytical research.
Timber-based hybrid structures provide a prospective solution for utilizing environmentally friendly timber material in the construction of mid-rise or high-rise structures. This study mainly focuses on structural damage evaluation for a type of timber-steel hybrid structures, which incorporate prefabricated light wood frame shear walls into steel moment-resisting frames (SMRFs). The structural damage of such a hybrid structure was evaluated through shake table tests on a four-story large-scale timber-steel hybrid structure. Four ground motion records (i.e., Wenchuan earthquake, Canterbury earthquake, El-Centro earthquake, and Kobe earthquake) were chosen for the tests, with the consideration of three different probability levels (i.e., minor, moderate and major earthquakes) for each record. During the shake table tests, the hybrid structure performed quite well with visual damage only to wood shear walls. No visual damage in SMRF and the frame-to-wall connections was observed. The correlation of visual damage to seismic intensity, modal-based damage index and inter-story drift was discussed. The reported work provided a basis of knowledge for performance-based seismic design (PBSD) for such timber-based hybrid structures.
An entry from Ruth Gardner's blog for 30 March 2012 entitled, "Going, going, gone".
The "Lyttelton Review" newsletter for 11 June 2012, produced by the Lyttelton Harbour Information Centre.
The "Lyttelton Review" newsletter for 15 October 2012, produced by the Lyttelton Harbour Information Centre.
An entry from Ruth Gardner's blog for 22 September 2011 entitled, "Steady on Stilts".
An entry from Ruth Gardner's blog for 9 November 2011 entitled, "Amuri Abandoned".
An entry from Roz Johnson's blog for 21 April 2012 entitled, "Demolition of a high story building in Christchurch".
The Canterbury earthquakes, which started with the 7.1 magnitude event on September 4, 2010, caused significant damage in the region. The September 4 earthquakes brought substantial damage to land, buildings, and infrastructure, while the 6.3 magnitude earthquake on February 22, 2011 (and its subsequent aftershocks), brought even greater property damage, but also significant loss of life in addition to the region. Thousands were injured, and 185 persons died. A national State of Emergency was declared and remained in effect until April 30, 2011. A significant number of people required immediate assistance and support to deal with loss, injury, trauma experiences, and property damages. Many had to find alternate accommodation as their houses were too damaged to stay in. Of those affected, many were already vulnerable, and others had been too traumatized by the events to effectively deal with the challenges they were faced with. A number of human service organizations in the region, from both government and non-government sectors, joined forces to be able to more effectively and efficiently help those in need. This was the start of what would become known as the Earthquake Support Coordination Service. The aim of this report is to present an evaluation of the Earthquake Support Coordination Service and its collaborative organization, based on documentation and interviews with key stakeholders of the service. The aim is also to evaluate the service based on perspectives gathered among the clients as well as the coordinators working in the service. The final aim is to offer a reflection on the service model, and on what factors enabled the service, as well as recommendations regarding aspects of the service which may require review, and aspects which may be useful in other contexts.
An entry from Ruth Gardner's blog for 22 March 2012 entitled, "Lamenting the Loss".
The "Lyttelton Harbour Review" newsletter for 5 August 2013, produced by the Lyttelton Harbour Information Centre.
The "Lyttelton Review" newsletter for 19 March 2012, produced by the Lyttelton Harbour Information Centre.
An entry from Roz Johnson's blog for 19 January 2013 entitled, "New Home".
The Lyttelton Harbour Information Centre's "Community Earthquake Update" bulletin, published on Friday 23 September 2011.
The "Lyttelton Review" newsletter for 29 October 2012, produced by the Lyttelton Harbour Information Centre.
The Lyttelton Harbour Information Centre's "Community Earthquake Update" bulletin, published on Friday 22 July 2011.
The "Lyttelton Review" newsletter for 12 March 2012, produced by the Lyttelton Harbour Information Centre.
An entry from Ruth Gardner's blog for 5 October 2011 entitled, "Drilling Down".
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 news item titled, "Lyttelton Tunnel", published on the Lyttelton Harbour Information Centre's website on Thursday, 29 September 2011.
The "Lyttelton Harbour Review" newsletter for 4 February 2013, produced by the Lyttelton Harbour Information Centre.
The "Lyttelton Harbour Review" newsletter for 28 January 2013, produced by the Lyttelton Harbour Information Centre.
The "Lyttelton Review" newsletter for 30 January 2012, produced by the Lyttelton Harbour Information Centre.
The Lyttelton Harbour Information Centre's "Community Earthquake Update" bulletin, published on Friday 12 August 2011.
The "Lyttelton Harbour Review" newsletter for 24 June 2013, produced by the Lyttelton Harbour Information Centre.
This study evaluated and recommended a methodology for undertaking an earthquake risk assessment for Christchurch, incorporating hazard analysis, inventory collection, damage modelling and loss estimation. See Object Overview for background and usage information.
USAR codes and a yellow sticker can be seen on the doors of a damaged building. The yellow sticker was part of a building assessment system used following the February earthquake and indicates that this building has limited access and needs further evaluation.