Search

found 109040 results

Images for [empty query]; more images...

Research papers, The University of Auckland Library

The increasing prevalence of mixed-material buildings that combine concrete walls and steel frames in New Zealand, coupled with a lack of specific design and detailing guidelines for concrete wall-steel beam connections, underscores the need for comprehensive research to ensure that these structures behave as intended during earthquakes. Bolted web plate connections, commonly found in steel framing systems, are typically used to connect steel beams to concrete walls. These connections are idealised as pinned during design. However, research on steel framing systems has shown that these connections can develop significant stiffness and moment resistance when subjected to large rotations during seismic loading, potentially leading to brittle failure when used in concrete wall to steel beam applications. This thesis was written to understand the seismic performance of concrete wall-steel beam bolted web plate connections, providing experimental evidence, numerical modelling insights, and design recommendations to address critical gaps in current design practices. The study is divided into three phases. First, a review of 50 concrete wall-steel frame buildings in Auckland and Christchurch was conducted to understand current design practices and typical connection details. The findings revealed significant variation in design and detailing practices and a lack of specific guidelines for concrete wall-steel beam connections. Second, an experimental programme was conducted on four full-scale concrete wall-steel beam sub-assemblages, each incorporating variations in connection detailing. The tests were designed to quantify the rotation capacity of concrete wall-steel beam connections, identify failure modes and investigate the effectiveness of potential connection improvements. Results demonstrated that concrete wall-steel beam bolted web plate connections designed using current design standards and following existing practices are vulnerable to non-ductile failure characterised by concrete breakout. However, using slotted holes in the web plate and bent reinforcing bar anchors instead of headed stud anchors improved connection rotation capacity. Third, a numerical model of a case study building was developed on OpenSeesPy, with different connection conditions assumed based on the experimental results. Pushover and time history analyses were conducted to evaluate the implications of different connection conditions (pinned vs non-pinned) on global building response and local member demands. The findings revealed that using non-pinned connection conditions does not significantly affect the global building response and shear and bending moment demands on lateral load-resisting elements. However, doing so generates overstrength moments on the connections that induce different actions on out-of-plane concrete walls connected to steel beams. Synthesising findings from all three phases, this thesis concludes with a proposed design procedure for concrete wall-steel beam connections based on a capacity design approach to ensure ductile failure modes and suppress brittle ones. Key recommendations include selecting appropriate bolt hole geometry and anchorage, providing sufficient rotation capacity, and accounting for connection overstrength in global analyses.

Research papers, Victoria University of Wellington

The standard way in which disaster damages are measured involves examining separately the number of fatalities, of injuries, of people otherwise affected, and the financial damage that natural disasters cause. Here, we implement a novel way to aggregate these separate measures of disaster impact and apply it to two recent catastrophic events: the Christchurch (New Zealand) earthquakes and the Greater Bangkok (Thailand) floods of 2011. This new measure, which is similar to the World Health Organization’s calculation of Disability Adjusted Life Years (DALYs) lost from the burden of diseases and injuries, is described in detail in Noy (2014). It allows us to conclude that New Zealand lost 180 thousand lifeyears as a result of the 2011 events, and Thailand lost 2,644 thousand years. In per capita terms, the loss is similar, with both countries losing about 15 days per person due to the 2011 catastrophic events in these two countries. We also compare these events to other potentially similar events.

Research papers, Victoria University of Wellington

We examine the role of business interruption insurance in business recovery following the Christchurch earthquake in 2011 in the short- and medium-term. In the short-term analysis, we ask whether insurance increases the likelihood of business survival in the aftermath of a disaster. We find only weak evidence that those firms that had incurred damage, but were covered by business interruption insurance, had higher likelihood of survival post-quake compared with those firms that did not have insurance. This absence of evidence may reflect the high degree of uncertainty in the months following the 2011 earthquake and the multiplicity of severe aftershocks. For the medium-term, our results show a more explicit role for insurance in the aftermath of a disaster. Firms with business interruption insurance have a higher probability of increasing productivity and improved performance following a catastrophe. Furthermore, our results show that those organisations that receive prompt and full payments of their claims have a better recovery, in terms of profitability and a subjective ‘”better off” measure’ than those that had protracted or inadequate claim payments (less than 80% of the claim paid within 2.5 years). Interestingly, the latter group does worse than those organisations that had damage but no insurance coverage. This analysis strongly indicates the importance not only of good insurance coverage, but of an insurance system that also delivers prompt claim payments. As a first paper attempting to empirically identify a causal effect of insurance on business recovery, we also emphasize some caveats to our analysis.

Research papers, Victoria University of Wellington

Earthquakes are insured only with public sector involvement in high-income countries where the risk of earthquakes is perceived to be high. The proto-typical examples of this public sector involvement are the public earthquake insurance schemes in California, Japan, and New Zealand (NZ). Each of these insurance programs is structured differently, and the purpose of this paper is to examine these differences using a concrete case-study, the sequence of earthquakes that occurred in the Christchurch, New Zealand, in 2011. This event turned out to have been the most heavily insured earthquake event in history. We examine what would have been the outcome of the earthquakes had the system of insurance in NZ been different. In particular, we focus on the public earthquake insurance programs in California (the California Earthquake Authority - CEA), and in Japan (Japanese Earthquake Reinsurance - JER). Overall, the aggregate cost to the public insurer in NZ was $NZ 11.1 billion in its response to the earthquakes. If a similar-sized disaster event had occurred in Japan and California, homeowners would have received $NZ 2.5 billion and $NZ 1.4 billion from the JER and CEA, respectively. We further describe the spatial and distributive patterns of these different scenarios.

Research papers, Victoria University of Wellington

We measure the longer-term effect of a major earthquake on the local economy, using night-time light intensity measured from space, and investigate whether insurance claim payments for damaged residential property affected the local recovery process. We focus on the destructive Christchurch earthquake of 2011 as our case study. In this event more than 95% of residential housing units were covered by insurance, but insurance payments were staggered over 5 years, enabling us to identify their local impact. We find that night-time luminosity can capture the process of recovery and describe the recovery’s determinants. We also find that insurance payments contributed significantly to the process of economic recovery after the earthquake, but delayed payments were less affective and cash settlement of claims were more affective in contributing to local recovery than insurance-managed rebuilding.

Research papers, Victoria University of Wellington

We estimate the causal effects of a large unanticipated natural disaster on high schoolers’ university enrolment decisions and subsequent medium-term labour market outcomes. Using national administrative data after a destructive earthquake in New Zealand, we estimate that the disaster raises tertiary education enrolment of recent high school graduates by 6.1 percentage points. The effects are most pronounced for males, students who are academically weak relative to their peers, and students from schools directly damaged by the disaster. As relatively low ability males are overrepresented in sectors of the labour market helped by the earthquake, greater demand for university may stem from permanent changes in deeper behavioural parameters such as risk aversion or time preference, rather than as a coping response to poor economic opportunities.

Images, eqnz.chch.2010

20140522_8951_EOS M-22 Demolition Of what many in Christchurch know as the Millers building, but for many recent years was the home to the Christchurch City Council, till just a week or two before the first earthquake of 2010. Now, in mid-2014 it is finally being demolished after nearly 45 months empty. A bus is leaving the new (temporary) bu...

Images, eqnz.chch.2010

20140521_1080_1D3-24 It has started! Removal of the double-glazed windows is underway at my "red zone" house, now owned by the Government of New Zealand. Sold to CERA (the government agency) in October 2012 and has remained empty since, despite having little damage, apart from the tilt to the front from the land damage that occurred during the...

Images, eqnz.chch.2010

A sight becoming more common in post-earthquake Christchurch - lifting earthquake-affected buildings to allow their foundations to be replaced and or completely replaced.

Images, eqnz.chch.2010

Overlooking McCormacks bay out across the city with the Southern Alps as a backdrop. There is still a strong effect from the July 11, 2011 Volcanic erruption (Puyehue) in Chile. Ash made it over to New Zealand causing very strong colours at sunset. The colours have not been artificially changed and its not a mash up. The parts of the city (and...

Images, eqnz.chch.2010

Another house has gone from Seabreeze Close, Pacific Park, Bexley, leaving just the concrete base, a few floor tiles and the smashed toilet (throne). Houses are being demolished (85%) or deconstructed/shifted (15%) as a result of land damage in the major earthquakes of 4th September 2010, 22nd February 2011, 13th June 2011 and 23rd December 2...

Images, eqnz.chch.2010

Christchurch's Graffiti House... This Cranford Street house was damaged in the earthquakes and is due for demolished this week but has been given a Graffiti Makeover by local Street Artists.

Images, eqnz.chch.2010

20140927_2219_1D3-24 Planting natives at Harold Henry Park A planting of native bushes and trees in the old children's playground area in Bexley, Organised by the Facebook group Avon River Park and assisted by ex Bexley residents. This is right in the middle of the Bexley red zone with most houses removed or demolished now. #5832

Images, eqnz.chch.2010

Today (04/09/14) marks the fourth anniversary since the first earthquake rocked the city and greater Christchurch area. That first quake was magnitude 7.1, and luckily there was only one fatality (possible a heart attack). Since then we have had over 14,000 quakes, most very small in magnitude, but well over 500 of magnitude 4 or greater. 5...

Images, eqnz.chch.2010

The sign reads: The CTV Building was headquarters of Canterbury Television (CTV) and also housed King’s Education language School, a medical clinic, Hair Consultants, Relationship Services and a nursing school. On February 22nd 2011 the building collapsed as a result of a major earthquake. Sadly, 115 people who were in the building lost their l...

Images, eqnz.chch.2010

On a walk over to Hagley Park to great some shots of the wonderful Cherry Blossom I past by the Knox Church rebuild and found that the scaffolding has come down at last. It sure was shinning in the midday light. Victoria Street September 12, 2014 Christchurch New Zealand

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.

Images, eqnz.chch.2010

A crane topples over on Victoria Street while taking glass up to some windows. No one was hurt and the glass never broke. Victoria Street was closed from 7:30am to later in the evening. This all happen on the Knox Plaza building site. Christchurch October 13, 2014 New Zealand.