This paper discusses the seismic performance of the standard RC office building in Christchurch that is given as a structural design example in NZS3101, the concrete structures seismic standard in New Zealand. Firstly the push-over analysis was carried out to evaluate the lateral load carrying capacity of the RC building and then to compare that carrying capacity with the Japanese standard law. The estimated figures showed that the carrying capacity of the New Zealand standard RC office building of NZS3101:2006 was about one third of Japanese demanded carrying capacity. Secondly, time history analysis of the multi-mass system was performed to estimate the maximum response story drift angle using recorded ground motions. Finally, a three-dimensional analysis was carried out to estimate the response of the building to the 22nd February, 2011 Canterbury earthquake. The following outcomes were obtained. 1) The fundamental period of the example RC building is more than twice that of Japanese simplified calculation, 2) The example building’s maximum storey drift angle reached 2.5% under the recorded ground motions. The main purpose of this work is to provide background information of seismic design practice for the reconstruction of Christchurch.
The 2010/2011 Canterbury earthquakes have provided a unique opportunity to investigate the seismic performance of both traditional and modern buildings constructed in New Zealand. It is critical that the observed performance is examined and compared against the expected levels of performance that are outlined by the Building Code and Design Standards. In particular, in recent years there has been a significant amount of research into the seismic behaviour of precast concrete floor systems and the robustness of the support connections as a building deforms during an earthquake. An investigation of precast concrete floor systems in Christchurch has been undertaken to assess both the performance of traditional and current design practice. The observed performance for each type of precast floor unit was collated from a number of post-earthquake recognisance activities and compared against the expected performance determined for previous experimental testing and analysis. Possible reasons for both the observed damage, and in some cases the lack of damage, were identified. This critical review of precast concrete floor systems will assist in determining the success of current design practice as well as identify any areas that require further research and/or changes to design standards.
The recent earthquakes in Christchurch have made it clear that issues exist with current RC frame design in New Zealand. In particular, beam elongation in RC frame buildings was widespread and resulted in numerous buildings being rendered irreparable. Design solutions to overcome this problem are clearly needed, and the slotted beam is one such solution. This system has a distinct advantage over other damage avoidance design systems in that it can be constructed using current industry techniques and conventional reinforcing steel. As the name suggests, the slotted beam incorporates a vertical slot along part of the beam depth at the beam-column interface. Geometric beam elongation is accommodated via opening and closing of these slots during seismically induced rotations, while the top concrete hinge is heavily reinforced to prevent material inelastic elongation. Past research on slotted beams has shown that the bond demand on the bottom longitudinal reinforcement is increased compared with equivalent monolithic systems. Satisfying this increased bond demand through conventional means may yield impractical and economically less viable column dimensions. The same research also indicated that the joint shear mechanism was different to that observed within monolithic joints and that additional horizontal reinforcement was required as a result. Through a combination of theoretical investigation, forensic analysis, and database study, this research addresses the above issues and develops design guidelines. The use of supplementary vertical joint stirrups was investigated as a means of improving bond performance without the need for non-standard reinforcing steel or other hardware. These design guidelines were then validated experimentally with the testing of two 80% scale beam-column sub-assemblies. The revised provisions for bond within the bottom longitudinal reinforcement were found to be adequate while the top longitudinal reinforcement remained nominally elastic throughout both tests. An alternate mechanism was found to govern joint shear behaviour, removing the need for additional horizontal joint reinforcement. Current NZS3101:2006 joint shear reinforcement provisions were found to be more than adequate given the typically larger column depths required rendering the strut mechanism more effective. The test results were then used to further refine design recommendations for practicing engineers. Finally, conclusions and future research requirements were outlined.
Four cartoons in the same frame commenting on news and happenings in the week ending 15 December 2011. The cartoons refer to the expulsion of the controversial Member of Parliament, Brendan Horan, from the New Zealand First Party by its leader, Winston Peters; the stereotyping of New Zealand as being 'Middle Earth' following the filming of 'The Hobbit', punned as 'The Habbit'; the lax attitude to building design and standards, which led to the CTV Building disaster in the Christchurch earthquake; the news about the New Zealand SPCA teaching dogs to drive.
Quantity: 1 digital cartoon(s).
A preliminary case study assessing the seismic sustainability of two reinforced concrete structures, a frame structure and a wall structure, was conducted to determine which structural system is more seismically sustainable. The two structures were designed to the same standards and were assumed to be located in Christchurch, New Zealand. A component-based probabilistic seismic loss assessment, considering direct losses only, was conducted for two ground motion records, regarded to approximately represent a 1 in 500 year earthquake event and a 1 in 2500 year earthquake event, respectively. It is shown that the wall structure results in lower direct losses than the frame structure in the less severe ground motion scenario. However, in the more severe ground motion scenario, the frame structure results in lower direct losses. Hence, this study demonstrates that which structural system has the lower direct losses depends on the ground motion intensity level.
Despite over a century of study, the relationship between lunar cycles and earthquakes remains controversial and difficult to quantitatively investigate. Perhaps as a consequence, major earthquakes around the globe are frequently followed by 'prediction' claims, using lunar cycles, that generate media furore and pressure scientists to provide resolute answers. The 2010-2011 Canterbury earthquakes in New Zealand were no exception; significant media attention was given to lunarderived earthquake predictions by non-scientists, even though the predictions were merely 'opinions' and were not based on any statistically robust temporal or causal relationships. This thesis provides a framework for studying lunisolar earthquake temporal relationships by developing replicable statistical methodology based on peer reviewed literature. Notable in the methodology is a high accuracy ephemeris, called ECLPSE, designed specifically by the author for use on earthquake catalogs, and a model for performing phase angle analysis. The statistical tests were carried out on two 'declustered' seismic catalogs, one containing the aftershocks from the Mw7.1 earthquake in Canterbury, and the other containing Australian seismicity from the past two decades. Australia is an intraplate setting far removed from active plate boundaries and Canterbury is proximal to a plate boundary, thus allowing for comparison based on tectonic regime and corresponding tectonic loading rate. No strong, conclusive, statistical correlations were found at any level of the earthquake catalogs, looking at large events, onshore events, offshore events, and the fault type of some events. This was concluded using Schuster's test of significance with α=5% and analysis of standard deviations. A few weak correlations, with p-5-10% of rejecting the null hypothesis, and anomalous standard deviations were found, but these are difficult to interpret. The results invalidate the statistical robustness of 'earthquake predictions' using lunisolar parameters in this instance. An ambitious researcher could improve on the quality of the results and on the range of parameters analyzed. The conclusions of the thesis raise more questions than answers, but the thesis provides an adaptable methodology that can be used to further investigation the problem.
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.
TODD McCLAY to the Minister of Finance: What progress has the Government made with its economic programme in 2012?
Dr RUSSEL NORMAN to the Prime Minister: Does he stand by his promise to New Zealanders that "I expect high standards from my Ministers … if they don't meet the standards I set then obviously I will take action if necessary"?
DAVID SHEARER to the Prime Minister: Does he stand by all his statements and have confidence in the statements of all his Ministers?
NICKY WAGNER to the Minister for Canterbury Earthquake Recovery: How is the Government delivering a strong and effective recovery for greater Christchurch following the earthquakes?
CHARLES CHAUVEL to the Minister of Justice: What are the specific "assumptions" based on "incorrect facts" demonstrating some "misunderstanding of New Zealand law" that she alleges are contained in the report of Justice Binnie concerning the application by Mr Bain for compensation for wrongful conviction and imprisonment?
Dr PAUL HUTCHISON to the Minister of Health: What progress has the Government made on its national preventive health targets this year?
Rt Hon WINSTON PETERS to the Prime Minister: Why does he have confidence in the Minister for Whānau Ora?
KRIS FAAFOI to the Minister of Police: Is she committed to all of her promises in regards to the New Zealand Police?
TIM MACINDOE to the Minister of Justice: What progress has been made towards achieving Better Public Services across the justice sector?
HONE HARAWIRA to the Minister of Education: Does she accept the finding of the Children's Commissioner's Expert Advisory Group on Solutions to Child Poverty that a government funded food programme in low-decile schools is a simple, do-able, and low-cost solution to help children in poverty learn and achieve at school, and the recommendation that Government design and implement such a programme; if not, why not?
CHRIS HIPKINS to the Minister of Education: Does she believe that her consultation process around the possible closure of residential special schools provided all those affected with an opportunity to have a meaningful say and have that say properly considered; if so, why?
MELISSA LEE to the Minister for Social Development: What progress has the Government made in 2012 to shift the focus of our welfare system to one that is active, work focused and delivers better outcomes for New Zealanders?
TODD McCLAY to the Minister of Finance: What progress has the Government made with its economic programme in 2012?
Dr RUSSEL NORMAN to the Prime Minister: Does he stand by his promise to New Zealanders that "I expect high standards from my Ministers … if they don't meet the standards I set then obviously I will take action if necessary"?
DAVID SHEARER to the Prime Minister: Does he stand by all his statements and have confidence in the statements of all his Ministers?
NICKY WAGNER to the Minister for Canterbury Earthquake Recovery: How is the Government delivering a strong and effective recovery for greater Christchurch following the earthquakes?
CHARLES CHAUVEL to the Minister of Justice: What are the specific "assumptions" based on "incorrect facts" demonstrating some "misunderstanding of New Zealand law" that she alleges are contained in the report of Justice Binnie concerning the application by Mr Bain for compensation for wrongful conviction and imprisonment?
Dr PAUL HUTCHISON to the Minister of Health: What progress has the Government made on its national preventive health targets this year?
Rt Hon WINSTON PETERS to the Prime Minister: Why does he have confidence in the Minister for Whānau Ora?
KRIS FAAFOI to the Minister of Police: Is she committed to all of her promises in regards to the New Zealand Police?
TIM MACINDOE to the Minister of Justice: What progress has been made towards achieving Better Public Services across the justice sector?
HONE HARAWIRA to the Minister of Education: Does she accept the finding of the Children's Commissioner's Expert Advisory Group on Solutions to Child Poverty that a government funded food programme in low-decile schools is a simple, do-able, and low-cost solution to help children in poverty learn and achieve at school, and the recommendation that Government design and implement such a programme; if not, why not?
CHRIS HIPKINS to the Minister of Education: Does she believe that her consultation process around the possible closure of residential special schools provided all those affected with an opportunity to have a meaningful say and have that say properly considered; if so, why?
MELISSA LEE to the Minister for Social Development: What progress has the Government made in 2012 to shift the focus of our welfare system to one that is active, work focused and delivers better outcomes for New Zealanders?
