Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.135-152
S. Uma, F. Scheele, E. Abbott, J. Moratalla
Water networks are vulnerable to earthquakes and failures of network components can result in a lack of availability of services, sometimes leading to relocation of the community. In New Zealand, there are statutory requirements for the water network providers to address the resilience of infrastructure assets. This is done by identifying and managing risks related to natural hazards and planning for appropriate financial provision to manage those risks. In addition to this, the impact from the Canterbury region earthquakes has accelerated the need for understanding the potential risk to critical infrastructure networks to minimise socio-economic impact. As such, there is a need for developing pragmatic approaches to deliver appropriate hazard and risk information to the stakeholders. Within the context of improving resilience for water networks, this study presents a transparent and staged approach to risk assessment by adopting three significant steps: (i) to define an earthquake hazard scenario for which the impact needs to be assessed and managed; (ii) to identify vulnerable parts of the network components; and (iii) to estimate likely outage time of services in the areas of interest. The above process is illustrated through a case study with water supply and wastewater networks of Rotorua Lakes Council by estimating ground motion intensities, damage identification and outage modelling affected by number of crews and preferred repair strategies. This case study sets an example by which other councils and/or water network managers could undertake risk assessment studies underpinned by science models and develop resilience management plans.
{"title":"Planning for resilience of water networks under earthquake hazard","authors":"S. Uma, F. Scheele, E. Abbott, J. Moratalla","doi":"10.5459/BNZSEE.54.2.135-152","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.135-152","url":null,"abstract":"Water networks are vulnerable to earthquakes and failures of network components can result in a lack of availability of services, sometimes leading to relocation of the community. In New Zealand, there are statutory requirements for the water network providers to address the resilience of infrastructure assets. This is done by identifying and managing risks related to natural hazards and planning for appropriate financial provision to manage those risks. In addition to this, the impact from the Canterbury region earthquakes has accelerated the need for understanding the potential risk to critical infrastructure networks to minimise socio-economic impact. As such, there is a need for developing pragmatic approaches to deliver appropriate hazard and risk information to the stakeholders. Within the context of improving resilience for water networks, this study presents a transparent and staged approach to risk assessment by adopting three significant steps: (i) to define an earthquake hazard scenario for which the impact needs to be assessed and managed; (ii) to identify vulnerable parts of the network components; and (iii) to estimate likely outage time of services in the areas of interest. The above process is illustrated through a case study with water supply and wastewater networks of Rotorua Lakes Council by estimating ground motion intensities, damage identification and outage modelling affected by number of crews and preferred repair strategies. This case study sets an example by which other councils and/or water network managers could undertake risk assessment studies underpinned by science models and develop resilience management plans.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126322626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.82-96
Alistair J. Davies, Conrad Zorn, T. Wilson, L. Wotherspoon, S. Beavan, T. Davies, M. Hughes
While it is well established that community members should participate in resilience planning, participation with genuine decision-making power remains rare. We detail an end-to-end disaster impact reduction modelling framework for infrastructure networks, embedded within a scenario-based participatory approach. Utilising the AF8+ earthquake scenario, we simulate hazard exposure, asset failure and recovery of interdependent critical infrastructure networks. Quantifying service levels temporally offers insights into possible interdependent network performance and community disconnection from national networks, not apparent when studying each infrastructure in isolation. Sequencing participation enables feedbacks between integrated modelling and participants’ impact assessments. Shared ownership of modelling outputs advances stakeholders’ understanding of resilience measures, allowing real-time implementation, increasing community resilience. Readily understood by central government, this format may increase support and resourcing, if nationally significant. Finally, this method tested integrated modelling and impacts assessments, identifying and enabling improvements for both.
{"title":"Infrastructure failure propagations and recovery strategies from an Alpine Fault earthquake scenario","authors":"Alistair J. Davies, Conrad Zorn, T. Wilson, L. Wotherspoon, S. Beavan, T. Davies, M. Hughes","doi":"10.5459/BNZSEE.54.2.82-96","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.82-96","url":null,"abstract":"While it is well established that community members should participate in resilience planning, participation with genuine decision-making power remains rare. We detail an end-to-end disaster impact reduction modelling framework for infrastructure networks, embedded within a scenario-based participatory approach. Utilising the AF8+ earthquake scenario, we simulate hazard exposure, asset failure and recovery of interdependent critical infrastructure networks. Quantifying service levels temporally offers insights into possible interdependent network performance and community disconnection from national networks, not apparent when studying each infrastructure in isolation. Sequencing participation enables feedbacks between integrated modelling and participants’ impact assessments. Shared ownership of modelling outputs advances stakeholders’ understanding of resilience measures, allowing real-time implementation, increasing community resilience. Readily understood by central government, this format may increase support and resourcing, if nationally significant. Finally, this method tested integrated modelling and impacts assessments, identifying and enabling improvements for both.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133582938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.163-175
P. Brabhaharan
Wellington region’s transport network has poor resilience to natural hazards, given the rugged terrain, high seismicity and wet climate. This exposes the land access to the region and the capital city to be potentially cut off from the rest of New Zealand for several months, and its cities to be isolated from each other. This paper reports on a pioneering integrated resilience study of the entire land transport system in the region provided by the state highways, principal and arterial local roads and the railway system. The study considered resilience risks from a range of natural hazards (earthquake, storm and tsunami) using the metrics of availability and outage. The resilience risks and the relative importance of the routes were used to assess the criticality of these risks for future investment in resilience enhancement. The criticality also considered risks to other lifeline utilities - power, water and telecommunications that share these transport corridors. The combined criticality was used to prioritise these resilience risks. The highest criticality resilience risks were classified into extreme, very high and high levels. The extreme criticality risks identified were the state highway between Ngauranga and Petone and the adjacent Ngauranga interchange between the two State Highways 1 and 2, which together provide access between Wellington, Hutt and Porirua cities. A range of very high risks were identified across the region which included both state highways and local roads. This novel resilience study provided the basis for a subsequent business case for future investment to enhance the resilience of the region’s transport network.
{"title":"Integrated Wellington region land transport resilience study","authors":"P. Brabhaharan","doi":"10.5459/BNZSEE.54.2.163-175","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.163-175","url":null,"abstract":"Wellington region’s transport network has poor resilience to natural hazards, given the rugged terrain, high seismicity and wet climate. This exposes the land access to the region and the capital city to be potentially cut off from the rest of New Zealand for several months, and its cities to be isolated from each other. \u0000This paper reports on a pioneering integrated resilience study of the entire land transport system in the region provided by the state highways, principal and arterial local roads and the railway system. The study considered resilience risks from a range of natural hazards (earthquake, storm and tsunami) using the metrics of availability and outage. The resilience risks and the relative importance of the routes were used to assess the criticality of these risks for future investment in resilience enhancement. The criticality also considered risks to other lifeline utilities - power, water and telecommunications that share these transport corridors. The combined criticality was used to prioritise these resilience risks. The highest criticality resilience risks were classified into extreme, very high and high levels. The extreme criticality risks identified were the state highway between Ngauranga and Petone and the adjacent Ngauranga interchange between the two State Highways 1 and 2, which together provide access between Wellington, Hutt and Porirua cities. A range of very high risks were identified across the region which included both state highways and local roads. This novel resilience study provided the basis for a subsequent business case for future investment to enhance the resilience of the region’s transport network.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114934561","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.97-116
E. Gkeli, P Brabhaharan, D. Novakov, Sivashanmugam Arumugam, Gunasekaran Mookaiya
Wellington city is characterised by steep hilly terrain, and as such several tunnels have been constructed since the beginning of the last century to provide critical transport access in the city. These tunnels are still used today as part of the city’s transport routes, while also being an integral part of the city’s history and heritage. Wellington is among the most seismically active areas in New Zealand. Three major active faults located within the Wellington Region and the proximity to the subduction zone are the main contributors to the high seismicity. The aging tunnels were designed and constructed prior to the advent of earthquake design standards and are subject to deterioration. Hence, they require maintenance and strengthening to ensure operational integrity and resilience to earthquake and other hazard events. Authorities have been supported by the authors in managing the risk through identifying key vulnerabilities, and prioritisation and implementation of strengthening measures. Best practice investigation and strengthening techniques have been applied through the process to ensure resilience and cost effectiveness. The paper presents case histories that highlight the value of investigations and assessment in understanding the risks, and novel strengthening measures developed to enhance resilience while preserving the heritage of the tunnels. Case histories include the seismic strengthening of the Hataitai Bus Tunnel, the Northland and Seatoun road tunnels and the investigation and assessment of the iconic Wellington Cable Car tunnels.
{"title":"Strengthening heritage tunnels to enhance the resilience of Wellington’s transport network","authors":"E. Gkeli, P Brabhaharan, D. Novakov, Sivashanmugam Arumugam, Gunasekaran Mookaiya","doi":"10.5459/BNZSEE.54.2.97-116","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.97-116","url":null,"abstract":"Wellington city is characterised by steep hilly terrain, and as such several tunnels have been constructed since the beginning of the last century to provide critical transport access in the city. These tunnels are still used today as part of the city’s transport routes, while also being an integral part of the city’s history and heritage. \u0000Wellington is among the most seismically active areas in New Zealand. Three major active faults located within the Wellington Region and the proximity to the subduction zone are the main contributors to the high seismicity. The aging tunnels were designed and constructed prior to the advent of earthquake design standards and are subject to deterioration. Hence, they require maintenance and strengthening to ensure operational integrity and resilience to earthquake and other hazard events. Authorities have been supported by the authors in managing the risk through identifying key vulnerabilities, and prioritisation and implementation of strengthening measures. Best practice investigation and strengthening techniques have been applied through the process to ensure resilience and cost effectiveness. \u0000The paper presents case histories that highlight the value of investigations and assessment in understanding the risks, and novel strengthening measures developed to enhance resilience while preserving the heritage of the tunnels. Case histories include the seismic strengthening of the Hataitai Bus Tunnel, the Northland and Seatoun road tunnels and the investigation and assessment of the iconic Wellington Cable Car tunnels.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122036455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.69-81
D. Mason, P. Brabhaharan
The Ward to Cheviot section of State Highway 1 is a key lifeline transport route that runs through the Kaikōura township. It is a strategically important link in the national state highway network, connecting the North Island via the Wellington-Picton ferry to the city of Christchurch in the South Island. Its strategic importance and vulnerable location between the mountainous Kaikōura range and the Pacific Ocean make it a critical transportation route in the national transport network. The route has been a focus for understanding the resilience of transport networks from as far back as 2000, when this section was used as a pilot study in early research into transport resilience. A further resilience assessment of this section was completed as part of a national state highway resilience study in mid-2016. Subsequently, the Mw 7.8 Kaikōura earthquake struck the northeast of the South Island on 14 November 2016, triggering thousands of large landslides and causing severe disruption to the transport network. The damage and disruption caused by the earthquake was comparable to that assessed in pre-earthquake studies of the resilience of the state highway. Landslides and embankment failures caused the most damage and disruption to the transport infrastructure, with the Main North Line railway closed for over 9 months and State Highway 1 closed for over a year. Post-earthquake landslides and debris flows triggered by storms caused additional damage and disruption during the recovery phase. Post-earthquake assessment of the corridor resilience was carried out to identify measures to enhance resilience as part of the recovery works. These measures included realigning the road and rail away from the steep hillsides, engineered works to reduce the potential for slope failure, and engineered works to reduce the potential for inundation of the corridor. The resilience assessments also enabled tactical and operational measures to be put in place to ensure safety while allowing the recovery operations to proceed in the context of enhanced risk associated with storm events and potential aftershocks.
{"title":"Characterisation of transport resilience and measures to enhance resilience in the recovery after the 2016 Kaikōura earthquake","authors":"D. Mason, P. Brabhaharan","doi":"10.5459/BNZSEE.54.2.69-81","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.69-81","url":null,"abstract":"The Ward to Cheviot section of State Highway 1 is a key lifeline transport route that runs through the Kaikōura township. It is a strategically important link in the national state highway network, connecting the North Island via the Wellington-Picton ferry to the city of Christchurch in the South Island. Its strategic importance and vulnerable location between the mountainous Kaikōura range and the Pacific Ocean make it a critical transportation route in the national transport network. The route has been a focus for understanding the resilience of transport networks from as far back as 2000, when this section was used as a pilot study in early research into transport resilience. A further resilience assessment of this section was completed as part of a national state highway resilience study in mid-2016. Subsequently, the Mw 7.8 Kaikōura earthquake struck the northeast of the South Island on 14 November 2016, triggering thousands of large landslides and causing severe disruption to the transport network. The damage and disruption caused by the earthquake was comparable to that assessed in pre-earthquake studies of the resilience of the state highway. Landslides and embankment failures caused the most damage and disruption to the transport infrastructure, with the Main North Line railway closed for over 9 months and State Highway 1 closed for over a year. Post-earthquake landslides and debris flows triggered by storms caused additional damage and disruption during the recovery phase. Post-earthquake assessment of the corridor resilience was carried out to identify measures to enhance resilience as part of the recovery works. These measures included realigning the road and rail away from the steep hillsides, engineered works to reduce the potential for slope failure, and engineered works to reduce the potential for inundation of the corridor. The resilience assessments also enabled tactical and operational measures to be put in place to ensure safety while allowing the recovery operations to proceed in the context of enhanced risk associated with storm events and potential aftershocks.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127357142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.117-134
V. Sadashiva, R. Mowll, S. Uma, Sheng-Lin Lin, D. Heron, N. Horspool, M. Nayyerloo, J. Williams, Y. I. Syed, R. Buxton, A. King, B. Lukovic, K. Berryman, Michele Daly
Infrastructure networks (e.g. transport, water, energy, telecommunications) support life and the economy of communities of all sizes. New Zealand has witnessed several damaging earthquakes in the last decade that provide a compelling case to accelerate building resilient infrastructures in the country, so we can minimize any adverse impacts from future earthquakes. One of the regions that is highly vulnerable to earthquakes is Wellington. With the region’s population continually expanding and placing increased demands on its ageing infrastructures, with limited redundancy in the networks, and with many of its assets close to and / or intersecting fault lines, a large earthquake in the region could be highly disruptive, potentially resulting in serious social and economic consequences. While it may not be possible to completely avoid the impacts, they can be reduced. This paper provides an overview of the process taken in delivering a Wellington Lifelines Group report that demonstrates how impacts from a future major earthquake can be reduced through integrated and targeted infrastructure resilience investments. To quantify the benefits that can be achieved by making the proposed investments, impact modelling on nine different lifeline utilities in the Wellington metropolitan area were conducted; the assessment approach taken, and results derived and their use to prioritise resilience investments, are shown in this paper for selected key networks. The time-stamped service outage maps and tables produced from this work formed an essential input to evaluate and demonstrate the impact of the proposed resilience initiatives on the regional and national economies.
{"title":"Improving Wellington region’s resilience through integrated infrastructure resilience investments","authors":"V. Sadashiva, R. Mowll, S. Uma, Sheng-Lin Lin, D. Heron, N. Horspool, M. Nayyerloo, J. Williams, Y. I. Syed, R. Buxton, A. King, B. Lukovic, K. Berryman, Michele Daly","doi":"10.5459/BNZSEE.54.2.117-134","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.117-134","url":null,"abstract":"Infrastructure networks (e.g. transport, water, energy, telecommunications) support life and the economy of communities of all sizes. New Zealand has witnessed several damaging earthquakes in the last decade that provide a compelling case to accelerate building resilient infrastructures in the country, so we can minimize any adverse impacts from future earthquakes. One of the regions that is highly vulnerable to earthquakes is Wellington. With the region’s population continually expanding and placing increased demands on its ageing infrastructures, with limited redundancy in the networks, and with many of its assets close to and / or intersecting fault lines, a large earthquake in the region could be highly disruptive, potentially resulting in serious social and economic consequences. While it may not be possible to completely avoid the impacts, they can be reduced. This paper provides an overview of the process taken in delivering a Wellington Lifelines Group report that demonstrates how impacts from a future major earthquake can be reduced through integrated and targeted infrastructure resilience investments. To quantify the benefits that can be achieved by making the proposed investments, impact modelling on nine different lifeline utilities in the Wellington metropolitan area were conducted; the assessment approach taken, and results derived and their use to prioritise resilience investments, are shown in this paper for selected key networks. The time-stamped service outage maps and tables produced from this work formed an essential input to evaluate and demonstrate the impact of the proposed resilience initiatives on the regional and national economies.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116849811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.I-III
P Brabhaharan, L. Wotherspoon, R. Dhakal
1 Lead Guest Editor, National Technical Leader and Technical Director, Geotechnical Engineering and Resilience, WSP New Zealand, Wellington, brabha@wsp.com (Fellow). 2 Deputy Guest Editor, Associate Professor, University of Auckland, Auckland, liam.wotherspoon@auckland.ac.nz (Fellow) 3 Editor-in-Chief, Bulletin of the New Zealand Society for Earthquake Engineering, rajesh.dhakal@canterbury.ac.nz (Fellow) EDITORIAL
{"title":"Resilience of infrastructure networks","authors":"P Brabhaharan, L. Wotherspoon, R. Dhakal","doi":"10.5459/BNZSEE.54.2.I-III","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.I-III","url":null,"abstract":"1 Lead Guest Editor, National Technical Leader and Technical Director, Geotechnical Engineering and Resilience, WSP New Zealand, Wellington, brabha@wsp.com (Fellow). 2 Deputy Guest Editor, Associate Professor, University of Auckland, Auckland, liam.wotherspoon@auckland.ac.nz (Fellow) 3 Editor-in-Chief, Bulletin of the New Zealand Society for Earthquake Engineering, rajesh.dhakal@canterbury.ac.nz (Fellow) EDITORIAL","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"81 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124888655","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.153-162
Y. I. Syed, S. Uma, R. Prasanna, L. Wotherspoon
An infrastructure impact assessment process relies on the analysis of multiple types of models, the performance of individual infrastructure networks and the interdependencies between multiple infrastructure networks. Several models are developed for their specific purposes and there is a need to link these models for the assessment of natural hazard impacts on distributed infrastructures to deliver the desired outcomes on network functionality and disruption levels that are suitable to assess socio-economic impact. In this paper, an ‘end-to-end’ linkage structure is proposed to link different models by which various features, data standards, parameters and structures are linked in a transparent and consistent manner. The framework has adopted a dedicated knowledge discovery and data analysis process to acquire information around input and output parameters for each of these models developed by various researchers and used in risk assessment tools. The framework is illustrated by applying the step-by-step procedure towards integrated impact assessments of electricity, potable water and road networks and their interdependencies.
{"title":"‘End to end’ linkage structure for integrated impact assessment of infrastructure networks under natural hazards","authors":"Y. I. Syed, S. Uma, R. Prasanna, L. Wotherspoon","doi":"10.5459/BNZSEE.54.2.153-162","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.153-162","url":null,"abstract":"An infrastructure impact assessment process relies on the analysis of multiple types of models, the performance of individual infrastructure networks and the interdependencies between multiple infrastructure networks. Several models are developed for their specific purposes and there is a need to link these models for the assessment of natural hazard impacts on distributed infrastructures to deliver the desired outcomes on network functionality and disruption levels that are suitable to assess socio-economic impact. In this paper, an ‘end-to-end’ linkage structure is proposed to link different models by which various features, data standards, parameters and structures are linked in a transparent and consistent manner. The framework has adopted a dedicated knowledge discovery and data analysis process to acquire information around input and output parameters for each of these models developed by various researchers and used in risk assessment tools. The framework is illustrated by applying the step-by-step procedure towards integrated impact assessments of electricity, potable water and road networks and their interdependencies.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120897003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.58-68
Rocio L. Segura, J. Padgett, P. Paultre
Methods for the seismic analysis of dams have improved extensively in the last several decades. Advanced numerical models have become more feasible and constitute the basis of improved procedures for design and assessment. A probabilistic framework is required to manage the various sources of uncertainty that may impact system performance and fragility analysis is a promising approach for depicting conditional probabilities of limit state exceedance under such uncertainties. However, the effect of model parameter variation on the seismic fragility analysis of structures with complex numerical models, such as dams, is frequently overlooked due to the costly and time-consuming revaluation of the numerical model. To improve the seismic assessment of such structures by jointly reducing the computational burden, this study proposes the implementation of a polynomial response surface metamodel to emulate the response of the system. The latter will be computationally and visually validated and used to predict the continuous relative maximum base sliding of the dam in order to build fragility functions and show the effect of modelling parameter variation. The resulting fragility functions are used to assess the seismic performance of the dam and formulate recommendations with respect to the model parameters. To establish admissible ranges of the model parameters in line with the current guidelines for seismic safety, load cases corresponding to return periods for the dam classification are used to attain target performance limit states.
{"title":"Expected seismic performance of gravity dams using machine learning techniques","authors":"Rocio L. Segura, J. Padgett, P. Paultre","doi":"10.5459/BNZSEE.54.2.58-68","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.58-68","url":null,"abstract":"Methods for the seismic analysis of dams have improved extensively in the last several decades. Advanced numerical models have become more feasible and constitute the basis of improved procedures for design and assessment. A probabilistic framework is required to manage the various sources of uncertainty that may impact system performance and fragility analysis is a promising approach for depicting conditional probabilities of limit state exceedance under such uncertainties. However, the effect of model parameter variation on the seismic fragility analysis of structures with complex numerical models, such as dams, is frequently overlooked due to the costly and time-consuming revaluation of the numerical model. To improve the seismic assessment of such structures by jointly reducing the computational burden, this study proposes the implementation of a polynomial response surface metamodel to emulate the response of the system. The latter will be computationally and visually validated and used to predict the continuous relative maximum base sliding of the dam in order to build fragility functions and show the effect of modelling parameter variation. The resulting fragility functions are used to assess the seismic performance of the dam and formulate recommendations with respect to the model parameters. To establish admissible ranges of the model parameters in line with the current guidelines for seismic safety, load cases corresponding to return periods for the dam classification are used to attain target performance limit states.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126328237","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-06-01DOI: 10.5459/BNZSEE.54.2.176-183
S. Raynor, M. Boston
High growth is increasingly forcing development of hazard prone land in the coastal city of Tauranga. A multi-hazard mapping tool developed to guide strategic growth planning in this natural hazard rich environment gives direct comparison of total hazard levels across the city. By aggregating individual hazards into a summative multi-hazard rating for each part of the city, urban planners and engineers have a decision support tool to aid city planning over the next 100 years. Tauranga growth requires 40,000 new homes over the next four decades in addition to the existing 57,000 homes. This 70% growth must squeeze within tight geographic constraints as Tauranga's 137,000 residents nestle around a harbour and are bound by open coast to the north and steep terrain to the south. This research quantifies Tauranga’s natural hazards of sea level rise, storm surge, coastal erosion, tsunami, earthquake shaking, liquefaction, landslides volcanic ashfall and flooding. Each hazard is spatially represented through hazard maps. Individual hazards are combined into a multi-hazard model to represent the aggregated hazard exposure of each point of the city. The multi-hazard exposure is spatially mapped using GIS allowing an area with tsunami, liquefaction and storm surge as dominant hazards to be directly compared with an area of different hazards such as flooding and landslides. Mapping of these hazards provides strategic input for building city resilience through land use planning and mitigation design. A pilot study area of 25 km2 selected from the Tauranga City Council total area of 135 km2 demonstrates the accumulated mapping approach. The pilot area contains a thorough representation of geology, elevation, landform and hazards that occur throughout the city. Our findings showed the highest aggregated hazard areas in Tauranga are along the coast. As is common with many beach resort towns this corresponds with the most popular living areas. The lower hazard areas suitable for urban growth are distributed mostly away from the open coast in the slightly elevated topography.
{"title":"Multi-hazard analysis and mapping of coastal Tauranga in support of resilience planning","authors":"S. Raynor, M. Boston","doi":"10.5459/BNZSEE.54.2.176-183","DOIUrl":"https://doi.org/10.5459/BNZSEE.54.2.176-183","url":null,"abstract":"High growth is increasingly forcing development of hazard prone land in the coastal city of Tauranga. A multi-hazard mapping tool developed to guide strategic growth planning in this natural hazard rich environment gives direct comparison of total hazard levels across the city. By aggregating individual hazards into a summative multi-hazard rating for each part of the city, urban planners and engineers have a decision support tool to aid city planning over the next 100 years. \u0000Tauranga growth requires 40,000 new homes over the next four decades in addition to the existing 57,000 homes. This 70% growth must squeeze within tight geographic constraints as Tauranga's 137,000 residents nestle around a harbour and are bound by open coast to the north and steep terrain to the south. \u0000This research quantifies Tauranga’s natural hazards of sea level rise, storm surge, coastal erosion, tsunami, earthquake shaking, liquefaction, landslides volcanic ashfall and flooding. Each hazard is spatially represented through hazard maps. Individual hazards are combined into a multi-hazard model to represent the aggregated hazard exposure of each point of the city. The multi-hazard exposure is spatially mapped using GIS allowing an area with tsunami, liquefaction and storm surge as dominant hazards to be directly compared with an area of different hazards such as flooding and landslides. Mapping of these hazards provides strategic input for building city resilience through land use planning and mitigation design. A pilot study area of 25 km2 selected from the Tauranga City Council total area of 135 km2 demonstrates the accumulated mapping approach. The pilot area contains a thorough representation of geology, elevation, landform and hazards that occur throughout the city. \u0000Our findings showed the highest aggregated hazard areas in Tauranga are along the coast. As is common with many beach resort towns this corresponds with the most popular living areas. The lower hazard areas suitable for urban growth are distributed mostly away from the open coast in the slightly elevated topography.","PeriodicalId":343472,"journal":{"name":"Bulletin of the New Zealand National Society for Earthquake Engineering","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126865443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}