New Zealand Research Applications of, and Developments in, Low Damage Technology for Steel Structures

2018 ◽  
Vol 763 ◽  
pp. 3-10 ◽  
Author(s):  
Gregory A. MacRae ◽  
George Charles Clifton ◽  
Michel Bruneau

Over the past few years, the South Island of New Zealand has been subject to significant sequences of earthquake shaking. In particular, 2010-2011 events affected the city of Christchurch resulting in large scale demolition of buildings. Also, the recent and continuing 11/2016 events caused severe damage in the countryside, in small towns, and moderate damage further afield. This paper describes “low damage construction” methods being used in NZ, and especially in the Christchurch rebuild, to limit the possibility of building demolition in future large seismic events. The buildings used in the Christchurch rebuild are generally supported by structural steel framing. These steel buildings include BRB systems, EBF systems with replaceable active links, rocking systems, base isolation using friction pendulum systems and/or lead-rubber dissipaters, RBS beams, lead extrusion dissipaters, yielding flexural dissipaters, and friction connections. Concerns about a number of currently used systems are discussed.

2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Alexandros Tsipianitis ◽  
Yiannis Tsompanakis

Liquid-filled tanks are effective storage infrastructure for water, oil, and liquefied natural gas (LNG). Many such large-scale tanks are located in regions with high seismicity. Therefore, very frequently base isolation technology has to be adopted to reduce the dynamic distress of storage tanks, preventing the structure from typical modes of failure, such as elephant-foot buckling, diamond-shaped buckling, and roof damage caused by liquid sloshing. The cost-effective seismic design of base-isolated liquid storage tanks can be achieved by adopting performance-based design (PBD) principles. In this work, the focus is given on sliding-based systems, namely, single friction pendulum bearings (SFPBs), triple friction pendulum bearings (TFPBs), and mainly on the recently developed quintuple friction pendulum bearings (QFPBs). More specifically, the study is focused on the fragility analysis of tanks isolated by sliding-bearings, emphasizing on isolators’ displacements due to near-fault earthquakes. In addition, a surrogate model has been developed for simulating the dynamic response of the superstructure (tank and liquid content) to achieve an optimal balance between computational efficiency and accuracy.


1985 ◽  
Vol 12 (1) ◽  
pp. 73-81
Author(s):  
S. F. Stiemer ◽  
B. B. Barwig

Base isolation is a strategy for a design of buildings in areas where seismic loads govern. It enables the reduction of earthquake excitation to an acceptable level, without an increase of structural acceleration. This paper presents the results of the experimental investigations of various schemes of first-storey designs for steel buildings with base isolation.A scaled-down steel frame building was used for the shaking table tests, which were conducted in the Earthquake Simulator Laboratory of the University of British Columbia. The base-storey design was altered while the dynamic response of the frame was recorded. The base isolation consisted of steel roller bearings with parallel steel yield rings, to limit excessive displacements and provide wind restraint.The proposed base storey is substantially different from conventional solutions. The variation in the base-storey design was aimed at the elimination of the blind base storey or double foundation in order to increase the economy of the base-isolation system. The experimental tests showed suitable design approaches, and analytical studies to optimize them will follow.It was verified that uncoupling of buildings from the earthquake ground motion is relatively simple to achieve. Certain restraint is required to resist wind and other horizontal loads. This is usually achieved by mechanical fuses or energy absorbers. A solid state energy absorber was used in the described tests. Key words: base-isolation system for buildings, earthquake-resistant steel structures, experimental investigations, retrofit system.


2020 ◽  
Vol 4 (1) ◽  
Author(s):  
Catherine M. Febria ◽  
Maggie Bayfield ◽  
Kathryn E. Collins ◽  
Hayley S. Devlin ◽  
Brandon C. Goeller ◽  
...  

In Aotearoa New Zealand, agricultural land-use intensification and decline in freshwater ecosystem integrity pose complex challenges for science and society. Despite riparian management programmes across the country, there is frustration over a lack in widespread uptake, upfront financial costs, possible loss in income, obstructive legislation and delays in ecological recovery. Thus, social, economic and institutional barriers exist when implementing and assessing agricultural freshwater restoration. Partnerships are essential to overcome such barriers by identifying and promoting co-benefits that result in amplifying individual efforts among stakeholder groups into coordinated, large-scale change. Here, we describe how initial progress by a sole farming family at the Silverstream in the Canterbury region, South Island, New Zealand, was used as a catalyst for change by the Canterbury Waterway Rehabilitation Experiment, a university-led restoration research project. Partners included farmers, researchers, government, industry, treaty partners (Indigenous rights-holders) and practitioners. Local capacity and capability was strengthened with practitioner groups, schools and the wider community. With partnerships in place, co-benefits included lowered costs involved with large-scale actions (e.g., earth moving), reduced pressure on individual farmers to undertake large-scale change (e.g., increased participation and engagement), while also legitimising the social contracts for farmers, scientists, government and industry to engage in farming and freshwater management. We describe contributions and benefits generated from the project and describe iterative actions that together built trust, leveraged and aligned opportunities. These actions were scaled from a single farm to multiple catchments nationally.


2011 ◽  
Vol 255-260 ◽  
pp. 2341-2344
Author(s):  
Mohammad Saeed Masoomi ◽  
Siti Aminah Osman ◽  
Ali Jahanshahi

This paper presents the performance of base-isolated steel structures under the seismic load. The main goals of this study are to evaluate the effectiveness of base isolation systems for steel structures against earthquake loads; to verify the modal analysis of steel frame compared with the hand calculation results; and development of a simulating method for base-isolated structure’s responses. Two models were considered in this study, one a steel structure with base-isolated and the other without base-isolated system. The nonlinear time-history analysis of both structures under El Centro 1940 seismic ground motion was used based on finite element method through SAP2000. The mentioned frames were analyzed by Eigenvalue method for linear analysis and Ritz-vector method for nonlinear analysis. Simulation results were presented as time-acceleration graphs for each story, period and frequency of both structures for the first three modes.


2004 ◽  
Vol 31 (3) ◽  
pp. 319 ◽  
Author(s):  
Jane Catherine Kitson

Sooty shearwaters (tītī, muttonbird, Puffinus griseus) are highly abundant migratory seabirds, which return to breeding colonies in New Zealand. The Rakiura Māori annual chick harvest on islands adjacent to Rakiura (Stewart Island), is one of the last large-scale customary uses of native wildlife in New Zealand. This study aimed to establish whether the rate at which muttonbirders can extract chicks from their breeding burrows indicates population trends of sooty shearwaters. Harvest rates increased slightly with increasing chick densities on Putauhinu Island. Birders' harvest rates vary in their sensitivities to changing chick density. Therefore a monitoring panel requires careful screening to ensure that harvest rates of the birders selected are sensitive to chick density, and represents a cross-section of different islands. Though harvest rates can provide only a general index of population change, it can provide an inexpensive and feasible way to measure population trends. Detecting trends is the first step to assessing the long-term sustainability of the harvest.


Author(s):  
Carla Houkamau ◽  
Petar Milojev ◽  
Lara Greaves ◽  
Kiri Dell ◽  
Chris G Sibley ◽  
...  

AbstractLongitudinal studies into the relationship between affect (positive or negative feelings) towards one’s own ethnic group and wellbeing are rare, particularly for Indigenous peoples. In this paper, we test the longitudinal effects of in-group warmth (a measure of ethnic identity affect) and ethnic identity centrality on three wellbeing measures for New Zealand Māori: life satisfaction (LS), self-esteem (SE), and personal wellbeing (PW). Longitudinal panel data collected from Māori (N = 3803) aged 18 or over throughout seven annual assessments (2009–2015) in the New Zealand Attitudes and Values Study were analyzed using latent trajectory models with structured residuals to examine cross-lagged within-person effects. Higher in-group warmth towards Māori predicted increases in all three wellbeing measures, even more strongly than ethnic identity centrality. Bi-directionally, PW and SE predicted increased in-group warmth, and SE predicted ethnic identification. Further, in sample-level (between-person) trends, LS and PW rose, but ethnic identity centrality interestingly declined over time. This is the first large-scale longitudinal study showing a strong relationship between positive affect towards one’s Indigenous ethnic group and wellbeing. Efforts at cultural recovery and restoration have been a deliberate protective response to colonization, but among Māori, enculturation and access to traditional cultural knowledge varies widely. The data reported here underline the role of ethnic identity affect as an important dimension of wellbeing and call for continued research into the role of this dimension of ethnic identity for Indigenous peoples.


Author(s):  
Amber Colibaba ◽  
Mark W. Skinner ◽  
Elizabeth Russell

Abstract During large-scale crises such as the COVID-19 pandemic, the precarity of older people and older volunteers can become exacerbated, especially in under-serviced rural regions and small towns. To understand how the pandemic has affected “older voluntarism”, this article presents a case study of three volunteer-based programs in rural Ontario, Canada. Interviews with 34 volunteers and administrators reveal both challenging and growth-oriented experiences of volunteers and the programs during the first wave of COVID-19. The findings demonstrate the vulnerability and resiliency of older volunteers and the adaptability and uncertainty of programs that rely on older voluntarism, as the community and its older residents navigate pandemic-related changes. The article advances a framework for understanding the pandemic’s impacts on older voluntarism in relation to personal, program, and community dimensions of sustainable rural aging. Further, it explores ways that older volunteers, organizations that depend on them, and communities experiencing population aging can persevere post-pandemic.


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