https://hdl.handle.net/2123/22635 Thu, 04 Jun 2026 11:01:28 GMT 2026-06-04T11:01:28Z https://hdl.handle.net/2123/35293 Dataset used for training and testing in “Physics-informed Graph Neural Networks for Operational Flood Modeling” paper Herath Mudiyanselage, Viraj Vidura Herath; Acosta, Carlo Malapad; Lim, Jia Yu; Saha, Abhishek; Rasnayaka, Sanka; Marshall, Lucy This dataset contains 2D hydrodynamic model simulation outputs and associated geometry files used for training and testing graph neural network (GNN) models presented in the paper “Physics-informed Graph Neural Networks for Operational Flood Modeling.” The paper has been accepted to the AI4Tech track of the IJCAI-ECAI 2026 conference, which will be held in Bremen from 15–21 August 2026. The preprint is available on arXiv (https://arxiv.org/abs/2512.23964v1), and the codebase can be accessed through GitHub (https://github.com/acostacos/dual_flood_gnn). Please refer to the README file for additional details regarding dataset structure and usage. Flood simulations were generated using the HEC-RAS hydrodynamic modelling software developed by the US Army Corps of Engineers (https://www.hec.usace.army.mil/software/hec-ras/). The Digital Elevation Model (DEM) for the Wollombi catchment was obtained from the ELVIS – Elevation and Depth – Foundation Spatial Data portal, accessible at ELVIS Portal (https://elevation.fsdf.org.au/). Synthetic forcing data used in the simulations were adapted from the paper “Interpretable physics-informed graph neural networks for flood forecasting” available at Wiley Online Library (https://onlinelibrary.wiley.com/doi/full/10.1111/mice.13484). Mon, 11 May 2026 00:00:00 GMT https://hdl.handle.net/2123/35293 2026-05-11T00:00:00Z https://hdl.handle.net/2123/35003 Flood depth maps used for training & testing in "Subgrid informed neural networks for high-resolution flood mapping" & "Flood-LDM: Generalizable latent diffusion models for rapid and accurate zero-shot high-resolution flood mapping" papers [Dataset] Herath Mudiyanselage, Viraj Vidura Herath; Marshall, Lucy; Saha, Abhishek; Rasnayaka, Sanka; Seneviratne, Sachith; Neo, Sun Han This dataset contains coarse-grid flood maps, fine-grid flood maps, and Digital Elevation Model (DEM) images with a spatial resolution of 512 × 512 pixels, which were used to train and evaluate deep learning models in the studies “Subgrid informed neural networks for high-resolution flood mapping” (https://doi.org/10.1016/j.jhydrol.2025.133329) and “Flood-LDM: Generalizable Latent Diffusion Models for Rapid and Accurate Zero-Shot High-Resolution Flood Mapping” (https://openaccess.thecvf.com/content/WACV2026/html/Neo_Flood-LDM_Generalizable_Latent_Diffusion_Models_for_rapid_and_accurate_zero-shot_WACV_2026_paper.html). Flood simulations for both coarse and fine computational grids were generated using the HEC-RAS hydraulic modelling software developed by the US Army Corps of Engineers (https://www.hec.usace.army.mil/software/hec-ras/). Simulations were conducted for three Australian catchments: Wollombi, Burnett, and Chowilla. DEM datasets for the Wollombi and Burnett catchments were obtained from the ELVIS – Elevation and Depth – Foundation Spatial Data portal (https://elevation.fsdf.org.au/), while the DEM for the Chowilla floodplain was sourced from the dataset provided by Niels Fraehr (https://doi.org/10.26188/21235782). Rainfall and inflow forcing data used to drive the hydrodynamic simulations were obtained from the Bureau of Meteorology Water Data Online portal (http://www.bom.gov.au/waterdata/). The dataset includes paired coarse- and fine-resolution flood depth maps together with corresponding DEM inputs, enabling the development and benchmarking of machine learning models for rapid high-resolution flood mapping. Flood depth values are provided in centimetres (cm), while DEM elevations are given in metres (m). Due to file size limitations, the dataset is distributed in multiple parts. Further methodological details and guidance on dataset usage can be found in the associated publications. Thu, 19 Mar 2026 00:00:00 GMT https://hdl.handle.net/2123/35003 2026-03-19T00:00:00Z https://hdl.handle.net/2123/34845 Supplementary Material for Power Dynamics and Community Participation in Climate Resilience Infrastructure: Examining Project Governance of the Leyte Tide Embankment Opdyke, Aaron; Lynn, Isabella; See, Justin; Cuaton, Ginbert Permejo; Peja, Pearly Joy These supplementary materials accompany the article "Power Dynamics and Community Participation in Climate Resilience Infrastructure: Examining Project Governance of the Leyte Tide Embankment". They contain the methodological instruments, including interview guides and surveys, in English and Waray-Wara, as well as the qualitative coding dictionary. Thu, 12 Feb 2026 00:00:00 GMT https://hdl.handle.net/2123/34845 2026-02-12T00:00:00Z https://hdl.handle.net/2123/33749 When is it convenient to split public transport lines? Gomez, Valentina; Jara-Diaz, Sergio; Fielbaum, Andres To serve a public transport demand on a corridor, it is possible to have just one line serving all of it, or two of them each serving one segment - which we refer to as one divided line. In this paper, we investigate theoretically under which conditions a divided line is better than a single line, minimizing the sum of users’ and operators’ costs. Both solutions are often encountered in real-life networks, with the division typically occurring on CBDs or subcenters. Understanding which is the optimal alternative is particularly relevant in the context of public transport network design, where most heuristics do not consider splitting lines as a potential step to improve their solutions. We formulate the problem in a generalized linear city, and optimize the frequency and vehicle size of each of the lines involved, to then compare the resulting costs of the full line versus the line divided at a given node. We prove that there are three conditions that favor the partition of a line, namely i) inducing few transfers, ii) a large difference in the maximum flows between the two segments, and iii) the segment with the lowest maximum flow being long. These conditions are synthesized into a divisibility index that can be calculated for each node, which is used to propose two algorithms to rapidly find where to split the line if convenient. The approach is tested numerically in a linear version of the Parametric City Model, where we compare the optimal set of lines with the ones resulting after dividing the full line following our algorithms with very good results. Fri, 28 Mar 2025 00:00:00 GMT https://hdl.handle.net/2123/33749 2025-03-28T00:00:00Z https://hdl.handle.net/2123/33661 Probabilistic Models for Australian Structural Loads Zhang, Hao Probabilistic models for (annual) extreme Australian wind action, imposed action, earthquake action, and permanent action are presented. The first and second order statistics for each of the actions are analysed in accordance with Australian loading standard AS1170. The load models can be used by engineers and material standard groups for evaluating structural reliability. Wed, 01 Jan 2025 00:00:00 GMT https://hdl.handle.net/2123/33661 2025-01-01T00:00:00Z https://hdl.handle.net/2123/33521 A Web of Nets: How Everything is a Network Levinson, David Matthew; Sarkar, Somwrita A Web of Nets, edited by David M. Levinson and Somwrita Sarkar explores the profound influence and universal relevance of networks, from physical systems to abstract constructs, connecting diverse fields and phenomena. Whether natural or man-made, these interconnected systems shape our understanding of science, technology, and culture. Structured into comprehensive sections, the book navigates through network principles, theories, and applications: Principles and Theory: Understand the foundational aspects of network science, including graph theory, topology, and network formation. Key concepts such as accessibility, resilience, and scaling reveal the hidden patterns underlying complex systems. Applications Across Domains: Biological Systems: Explore the networks within cells, organs, and ecosystems, revealing their interconnectedness and impact on life processes. Physical Systems: Delve into the cosmic web, chemical reactions, and transport systems, where networks determine flows, capacities, and dynamics. Technological Innovations: Learn about advancements in computing, communication, and infrastructure, illustrating how networks enable modern life. Social and Cultural Networks: Unpack the structure of social interactions, cultural exchanges, and economic markets, showing how they shape societies. Analysis and Evolution: Examine methods to analyze connectivity, centrality, and flow within networks, and understand their evolution over time. Techniques like PageRank, space syntax, and feedback loops provide powerful tools to decode network behavior. Emergent Phenomena: Discover how networks give rise to self-organization, emergent behaviors, and innovation. Case studies range from neural circuits and the brain's connectome to the assembly line and supply chains. Blending theoretical insights with practical applications, A Web of Nets is both a comprehensive reference and a thought-provoking exploration. It bridges disciplines, fostering a deeper appreciation of the patterns connecting the natural, physical, and human worlds. Engage with this captivating analysis to unlock a greater understanding of the networks shaping our universe. Wed, 01 Jan 2025 00:00:00 GMT https://hdl.handle.net/2123/33521 2025-01-01T00:00:00Z https://hdl.handle.net/2123/33276 The vertical-velocity skewness in the atmospheric boundary layer without buoyancy and Coriolis effects Katul, Gabriel; Heisel, Michael; Poggi, Davide; Peruzzi, Cosimo; Vettori, Davide; Manes, Costantino One of the main features of near-neutral atmospheric boundary layer (ABL) turbulence is the positive vertical velocity skewness Sk_w above the roughness sublayer or the buffer region in smooth-walls. The Sk_w variations are receiving renewed interest in many climate-related parameterizations of the ABL given their significance to cloud formation and to testing sub-grid schemes for Large Eddy Simulations (LES). The vertical variations of Sk_w are explored here using wind tunnel and flume experiments collected above smooth, rough, and permeable-walls in the absence of buoyancy and Coriolis effects. These laboratory experiments form a necessary starting point to probe the canonical structure of Sk_w as they deal with a key limiting case (i.e. near-neutral conditions). Diagnostic models based on cumulant expansions, realizability constraints, and constant mass flux approach routinely employed in the convective boundary layer as well as prognostic models based on third-order budgets are used to explain variations in Sk for the idealized laboratory conditions. The failure of flux-gradient relations to model Sk_w from the gradients of the vertical velocity variance \sigma_w^2 are explained and corrections based on models of energy transport offered. Novel links between the diagnostic and prognostic models are also featured, especially for the inertial term in the third order budget of the vertical velocity fluctuation. The co-spectral properties of w′/\sigma_w versus w′^2/\sigma_w^2 are also presented for the first time to assess the dominant scales governing Sk_w in the inner and outer layers, where w′ is the fluctuating vertical velocity and \sigma_w is the vertical velocity standard deviation. Mon, 01 Jan 2024 00:00:00 GMT https://hdl.handle.net/2123/33276 2024-01-01T00:00:00Z https://hdl.handle.net/2123/32751.2 Uncertain Waters: A Game of Collective Cooperation and Climate Change Opdyke, Aaron; Latham, Zoe; Barrett-Lennard, Grace This cooperative tabletop game immerses players in the complexities of managing flood risk under climate change. Players collaborate to implement adaptation strategies to protect community assets from flood impacts. Through dynamic gameplay and real-world decision-making scenarios, players must plan for evolving uncertainty and carefully allocate their resources to build a flood-resilient community. The game is suitable for 4-7 players and for ages 10+. The game is suitable for a range of applications and audiences, from use as a teaching tool for students to facilitating conversations between governments and communities. Fri, 05 Jul 2024 00:00:00 GMT https://hdl.handle.net/2123/32751.2 2024-07-05T00:00:00Z https://hdl.handle.net/2123/33039 High-Resolution Elevation Model and Orthomosaic of the Municipality of Carigara, Leyte, Philippines Opdyke, Aaron; Besarra, Isaac This dataset provides detailed topographical and visual information for coastal communities of the Municipality of Carigara, in the Province of Leyte in the Philippines. The data was collected through an aerial drone survey in July 2022. The package includes an orthomosaic, digital surface model (DSM), and digital terrain model (DTM). This dataset has applications for disaster risk reduction, coastal management, and land use planning in the Carigara coastal region. Tue, 03 Sep 2024 00:00:00 GMT https://hdl.handle.net/2123/33039 2024-09-03T00:00:00Z https://hdl.handle.net/2123/32983 On the departure from Monin–Obukhov surface similarity and transition to the convective mixed layer Heisel, Michael; Chamecki, Marcelo Large-eddy simulations are used to evaluate mean profile similarity in the convective boundary layer (CBL). Particular care is taken regarding the grid sensitivity of the profiles and the mitigation of inertial oscillations in the simulation spin-up. The nondimensional gradients \phi for wind speed and air temperature generally align with Monin–Obukhov similarity across cases but have a steeper slope than predicted within each profile. The same trend has been noted in several other recent studies. The Businger-Dyer relations are modified here with an exponential cutoff term to account for the decay in to first-order approximation, yielding improved similarity from approximately 0.05z_i to above 0.3 z_i, where z_i is the CBL depth. The necessity for the exponential correction is attributed to an extended transition from surface scaling to zero gradient in the mixed layer, where the departure from Monin–Obukhov similarity may be negligible at the surface but becomes substantial well below the conventional surface layer height of 0.1z_i. Mon, 01 Jan 2024 00:00:00 GMT https://hdl.handle.net/2123/32983 2024-01-01T00:00:00Z https://hdl.handle.net/2123/32982 Evidence of Mixed Scaling for Mean Profile Similarity in the Stable Atmospheric Surface Layer Heisel, Michael; Chamecki, Marcelo A new mixed scaling parameter Z = z/(Lh)^1/2 is proposed for similarity in the stable atmospheric surface layer, where z is the height, L is the Obukhov length, and h is the boundary layer depth. In comparison with the parameter z = z/L from Monin–Obukhov similarity theory (MOST), the new parameter Z leads to improved mean profile similarity for wind speed and air temperature in large-eddy simulations. It also yields the same linear similarity relation for CASES-99 field measurements, including in the strongly stable (but still turbulent) regime where large deviations from MOST are observed. Results further suggest that similarity for turbulent energy dissipation rate depends on both Z and z. The proposed mixed scaling of Z and relevance of h can be explained by physical arguments related to the limit of z-less stratification that is reached asymptotically above the surface layer. The presented evidence and fitted similarity relations are promising, but the results and arguments are limited to a small sample of idealized stationary stable boundary layers. Corroboration is needed from independent datasets and analyses, including for complex and transient conditions not tested here. Sun, 01 Jan 2023 00:00:00 GMT https://hdl.handle.net/2123/32982 2023-01-01T00:00:00Z https://hdl.handle.net/2123/32842 Leveraging inter-organizational coordination networks for housing climate change adaptation across rural Alaska Taylor, Jessica; Poleacovschi, Cristina; Opdyke, Aaron; Certin, Kristen Climate change impacts on housing are an essential concern for Alaska Native communities. Adaptation literature has largely ignored the role of inter-organizational coordination networks in supporting housing adaptation. To address this gap, we surveyed 26 organizations and 36 participants from organizations working regionally in rural Alaska on housing service, construction, and engineering projects. We employ social network analysis (SNA), including Logistic Regression Quadratic Assignment Procedure (LRQAP), to explore the influence of network centrality on an organization’s ability to enact housing adaptation. Results indicate that when two organizations have similarities in their network centrality, or how connected an organization was in the network, the less likely they are to have similar, positive views in their ability to enact housing adaptation. With a limited capacity to prepare for climate change impacts and integrate adaptation into existing programs, it is important for organizations and governments to mobilize the entirety of inter-organizational coordination networks. Mon, 01 Jan 2024 00:00:00 GMT https://hdl.handle.net/2123/32842 2024-01-01T00:00:00Z https://hdl.handle.net/2123/32790 Does safer housing save lives? An analysis of typhoon mortality and dwellings in the Philippines Healey, Sarah; Lloyd, Sophie; Gray, Jasmine; Opdyke, Aaron Storms globally account for the highest loss of life among weather-related natural hazards. This study examines the relationship between components of housing vulnerability and typhoon related mortality in the Philippines at a municipal level between 2005 and 2015 using a Hurdle Negative Binomial (HNB) model. We find that in municipalities with greater prevalence of extreme substandard housing, unimproved household water sources, crowdedness, lower housing density, and less secure tenure, people are more likely to die from typhoons when controlling for typhoon proximity and wind speed as well as coastal proximity. We recommend targeted investments in safer housing in municipalities of Region VIII, Region XI and the Bangsamoro Autonomous Region of Muslim Mindanao (BARMM) where correlations between housing vulnerability and disaster mortality are the highest. This research provides new knowledge of the link between housing and mortality in disasters, offering one of the first national scale assessments to quantify the contributions of safer housing in reducing loss of life in disasters. Sun, 01 Jan 2023 00:00:00 GMT https://hdl.handle.net/2123/32790 2023-01-01T00:00:00Z https://hdl.handle.net/2123/32788 Social vulnerability to natural hazards in the Philippines Lloyd, Sophie; Gray, Jasmine; Healey, Sarah; Opdyke, Aaron This research sought to measure social vulnerability at the municipal level across the Philippines. Indicators of social vulnerability were identified from literature and relevant census data was collected from the Philippines Statistics Authority (PSA). Principal Component Analysis (PCA) was used to identify underlying components of social vulnerability from this data, and these principal components, as well as an aggregated Social Vulnerability Index (SVI), were mapped at the municipal level. Negative Binomial (NB) regression analysis was then used to validate the SVI using typhoon mortality rates, with results indicating that a one standard deviation (SD) increase in social vulnerability is positively correlated with a 23.4% increase in observed typhoon-related fatalities. The development of a granular and validated SVI can guide researchers seeking to understand how localised vulnerability contributes to disaster risk in the Philippines and assist policymakers in prioritising local government units for disaster risk reduction interventions. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/32788 2022-01-01T00:00:00Z https://hdl.handle.net/2123/32521 Promoting migration as adaptation to climate change: addressing mobility barriers Nabong, Emily; Opdyke, Aaron In the past decade, there has been growing pushback towards the idea of migration as a “failure to adapt” to climate change. Climate-related migration is increasingly viewed as an adaptation strategy rather than the consequence of failed in situ adaptation (McLeman and Smit 2006). As we move toward a more nuanced understanding of the interaction between climate change and migration, governments now need to work towards strategies to aid safe and supported mobility. In particular, we stress that the responsibility rests heavily with countries from the Global North who have contributed the most to carbon emissions, while the burden of adaptation has disproportionately fallen to low-emitting countries from the Global South. While we are gradually understanding the drivers that lead to migration, we know comparatively less about the factors that compel people to stay (Wiegel, Boas, and Warner 2019). Unpacking the puzzle of immobility factors is a vital but often neglected pathway to assisting climate-affected populations who are unable or unwilling to move. This viewpoint provides a commentary on top factors that keep climate-affected populations in place, detailing how they contribute to immobility as well as recommendations towards overcoming these barriers. Sun, 01 Jan 2023 00:00:00 GMT https://hdl.handle.net/2123/32521 2023-01-01T00:00:00Z https://hdl.handle.net/2123/31069 Stiffness Reduction of Cold-Formed Steel Structures Subject to Sectional Buckling and Yielding Rasmussen, Kim JR The paper develops a stiffness reduction factor to be used in geometric nonlinear beam-element type elastic analysis of cold-formed steel structures. The factor accounts for the reduction in flexural and warping torsion rigidities resulting from local and distortional buckling as well as residuals stresses, as particular to cold-formed steel structures. The purpose of applying the factor is to accurately account for the geometric second order effects when predicting the internal distributions of moments of cold-formed steel structural frames. The stiffness reduction factor arising from local and distortional buckling is first determined followed by the stiffness reduction factor caused by residual stresses. Subsequently, the two effects are combined in a single expression is a format suitable for incorporation in the North American specification for cold-formed steel structures, AISI-S100. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/31069 2022-01-01T00:00:00Z https://hdl.handle.net/2123/31049 Strengths and Fracture Strains of Weld and HAZ in Welded Connections Liu, Xiaofan; Yan, Shen; Rasmussen, Kim JR; Deierlein, Gregory G This paper investigates the strengths and fracture strains of weld and heat affected zone (HAZ) in welded connections for both the longitudinal and transverse directions and compares them to those of the base metal. A series of miniature coupons, including miniature flat plates, notched round bars and grooved plates, were extracted from the three zones of a butt weld and tested using a custom-built jig. The true stress-strain relationships and fracture strains of the base metal, weld and HAZ materials were obtained for both directions from the miniature coupon tests and corresponding numerical simulations. The fracture strain data were used to calibrate the Lode angle modified void growth model (LMVGM) for predicting the fracture strain of the three material zones at any given stress state. The following major conclusions were drawn: (1) The weld was generally isotropic in terms of both strength and fracture strain. The weld also had the highest values of yield and tensile strengths among the three materials in both directions, but the lowest fracture strain in both directions except for the longitudinal direction with stress triaxiality above 0.21 to 0.30, for which the base metal had the lowest fracture strain. (2) The HAZ had higher yield and tensile strengths but smaller fracture strain in the longitudinal direction than in the transverse direction. The same anisotropic characteristic applied to the base metal. Meanwhile, the HAZ had higher yield and tensile strengths than the base metal as well as similar but slightly larger fracture strains in both directions. (3) The yield and tensile strengths of the weld and HAZ can be approximated using the empirical hardness-strength correlation functions, except that the functions tend to overestimate the strengths of the weld by about 10%. (4) For the weld, HAZ and base metal, the fracture surfaces tilted towards stress states with high stress triaxiality and low Lode angle parameter, indicating that fracture can initiate more easily at these stress states. Note that the above conclusions are limited to the tested AS350 grade steel and the selected welding parameters. Sun, 01 Jan 2023 00:00:00 GMT https://hdl.handle.net/2123/31049 2023-01-01T00:00:00Z https://hdl.handle.net/2123/31048 Fracture Investigation of Welded Cruciform Connections Liu, Xiaofan; Yan, Shen; Rasmussen, Kim JR; Deierlein, Gregory G As one of the main failure modes of steel structures, fracture in welded connections has widely been discussed based on experimental investigations and numerical simulations. However, the mechanical properties of the weld and Heat Affected Zone (HAZ), such as stress-strain relationships and fracture strains under various stress states, have rarely been considered in these analyses. Therefore, in this paper, the fracture process of welded connections is discussed to investigate the effects of the inhomogeneity of mechanical properties in the weld zone. Tensile tests are conducted on welded cruciform specimens fabricated using 8 mm or 12 mm fillet welds and finite element models are developed by considering or ignoring the material inhomogeneity in the weld zone. The simulation results are compared with the experimental and it is concluded that the assumption of homogenous properties within the weld zone using the properties of the base metal will underestimate the strength of the welded cruciform specimens and using the mechanical properties of the three material areas in the weld zone will increase the accuracy of the simulation results. Using the free parameters calibrated by the fracture strains of the three material areas, the fracture process of the welded cruciform specimens is simulated using the fracture model LMVGM, and the comparison shows that the mechanical properties of the weld and HAZ should be included in the investigation of fracture in welded connections to obtain reliable simulation results. Sun, 01 Jan 2023 00:00:00 GMT https://hdl.handle.net/2123/31048 2023-01-01T00:00:00Z https://hdl.handle.net/2123/30277 On the cooling potential of elastocaloric devices for building ventilation Ulpiani, Giulia; Saliari, Maria; Bruederlin, Florian; Kohl, Manfred; Ranzi, Gianluca; Santamouris, Mat Refrigerants in vapor-compression systems have a global warming potential thousands of times that of carbon dioxide, yet their spread on the market is unrivalled. Elastocaloric systems, based on solid state cooling, feature among the most promising alternatives. In this paper, an elastocaloric device for air ventilation (ECV) composed by parallel and serial connection of multiple shape memory alloy (SMA) films, is investigated via volume-based finite difference simulation in MATLAB and dynamic building simulation in TRNSYS considering eight cities across the globe. The models assume experimentally demonstrated thermal parameters for the elastocaloric phase transformation around room temperature and a single-storey reference building. The ECV operates according to an optimized, energy-saving logic that includes load partialization and recirculation. Parametric analyses suggest that moderate terminal velocities (~2 m/s) and a climate-specific design aimed at maximizing the use of the ECV device at nominal cooling capacity are key to reach building cooling needs reductions up to 70% in the considered scenarios. Partialization results in enhanced energy flexibility and conservation, whereas recirculation extends the ECV usability to extreme heat conditions. In absolute terms, the ECV works best under hot climates (e.g. Cairo, Dubai, Brisbane), with monthly cooling load reductions about 2/3-fold compared to cold locations (e.g. Milan, Hobart). The performance is extremely sensitive to the ventilation rate. Thermal zones requiring 1 to 2 air changes per hour are best suited. These findings provide initial insight into design criteria, opportunities and limitations on the use of elastocaloric devices for building ventilation to guide future experimental verification. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/30277 2021-01-01T00:00:00Z https://hdl.handle.net/2123/30275 Upscaling of SMA film-based elastocaloric cooling Ulpiani, Giulia; Bruederlin, Florian; Weidemann, Raphael; Ranzi, Gianluca; Santamouris, Mat; Kohl, Manfred A new concept of upscaling a shape memory alloy (SMA) film based elastocaloric cooling device is presented by arranging SMA films in parallel to increase the specific cooling capacity at low actuation force, while maintaining the large surface-to-volume ratio needed for rapid heat transfer. Selected materials are cold-rolled TiNiFe films that exhibit maximum adiabatic temperature changes of 27.3 and -18.1 K upon loading and unloading, respectively. Demonstrators are designed, fabricated and characterized consisting of five free-standing TiNiFe film bridges that are coupled antagonistically for work recovery. Thermomechanical cycling is performed by out-of-plane deflection of the SMA bridges, while heat transfer is established through mechanical contact with solid heat sink/source elements. The cooling capacity of the demonstrators scales with the number of active SMA films, which confirms the concept of parallelization for upscaling. Investigated demonstrators reach a maximum cooling capacity of about 900 mW compared to a maximum of about 200 mW achieved for reference devices consisting of a single TiNiFe film. The investigation also reveals a number of open issues related to narrow fabrication tolerances upon upscaling, which may cause different plastic straining and varying inhomogeneous stress accumulation among the individual SMA films. Wed, 01 Jan 2020 00:00:00 GMT https://hdl.handle.net/2123/30275 2020-01-01T00:00:00Z https://hdl.handle.net/2123/29949 Governing for Access Levinson, David M. The only reason to locate anywhere is to be near some people, places, and things (opportunities) and be far from others. Access quantifies the ability to reach, or be reached by, people, places, and things. It explains much of the variation in real estate prices and development density. It does so in large part because real estate capitalises into land value the ease of travel to desired opportunities. Physical infrastructure networks like roads and rails exist to connect within and between places faster than travel without them. Transport agencies often plan networks as if the land use is given, and regulators plan and zone development as if the network were unchangeable. Since the efficiency of a transport network depends on the land use pattern and the efficiency of the land use pattern depends on the network configuration, systems which coordinate these may be more efficient than those where transport and land use are planned independently. This is especially pertinent for long-term capital investments which are largely irreversible. While compared to some peer cities, Sydney has done a good job coordinating transport services and land development, it can do much better. This would lead to shorter commutes lengths, greater public and active transport mode shares, higher employment and incomes, and greater productivity. Overall Sydney would be a more desirable and convenient city. This is also important as better coordinating transport with land development while better balancing jobs and housing will thereby reduce motor vehicle travel. Reducing private vehicle travel will remain critical to addressing environmental problems such as CO2 emissions and air and water pollution, and increasing traveler safety. Modern urban planning confronts the challenge of coordinating policies in transport investment, land use and development regulation, budgets and taxation, and capital spending so that they reinforce instead of undermine each other.1 Several inter-related problems with transport - land use planning processes in New South Wales are apparent: 1. Mobility-centric transport planning and density-centric land use planning. 2. The uncoordinated and disjointed nature of decision making, wherein transport and land use decisions made by different organisations assume the other is unchanged. 3. Lack of systematic feedback in the infrastructure/land development cycle, so the gains in land value from new transport facilities don’t generate revenue could have helped fund the infrastructure in the first place. 4. The political cycle reversing long-term strategic planning decisions. 5. Lack of institutional knowledge caused by lack of long-term stability in senior staff and organisational structure. 6. Lack of domain expertise within operating agencies leading to: • Very high costs (and unexpectedly high costs) for infrastructure, reducing the capacity for investment. • Under-utilisation (over-forecast of demand) of many major new infrastructure projects. 7. Lack of transparency and authentic public participation in decision processes. This report contains several major parts. The next part, The Value of Access to Opportunity (chapter 2) discusses the framework of the Fundamental Model of Access. Then chapter 3 of the report, Operationalising Access describes formally how access is measured. This is followed be an examination of how Infill Stations Expand Access (chapter 4), including an example that illustrates how access might change between two public transport service scenarios when an infill station is added, and a sample of some potential sites for Infill Stations on the Sydney network are provided. Access-Oriented Planning Globally: Case Studies (chapter 5), discusses how integrated transport and land use planning is conducted in several key metropolitan regions globally. It looks at the governance structures in the Randstad (Amsterdam, Rotterdam, Utrecht, and The Hague) in the Netherlands, Singapore, Hong Kong, and Tokyo. The subsequent section, Governing for Access in New South Wales: A Future Sydney Commission (chapter 6), describes how long-term strategic transport - land use planning might be conducted in Greater Sydney, with an aim to address several of those inter-related problems. The final section (chapter 7) concludes the report, showing how the proposed strategy addresses the key problems identified above. Thu, 02 Feb 2023 00:00:00 GMT https://hdl.handle.net/2123/29949 2023-02-02T00:00:00Z https://hdl.handle.net/2123/29063 Intentional Travel Groups and Social Networks during the COVID-19 Pandemic Zhou, Mingzhi; Lei, Shuyu; Wu, Jiangyu; Ma, Hanxi; Levinson, David M.; Zhou, Jiangping Although face-to-face social contacts decreased during the COVID-19 pandemic, some people remain physically traveling and meeting as a group to gain benefits like sustaining intimacy and increasing productivity. Using multiday continuous smartcard data, we identify intentional group travel patterns in Hong Kong Metro system. Those patterns serve as our proxies for physical (visible) interactions and social (invisible) contact networks among people who intentionally travel as a group (ITGs). We measure the spatial centrality of ITGs and persistent group riders (PGRs), a subset of ITGs remaining active amid the pandemic, to infer different locales' social interactions in the city. By examining the social network formed by ITGs across time, we found that its size and interconnections varied during the pandemic and PGRs might be the most influential vertices in maintaining the networks’ topological properties. The findings could facilitate transit-usage-and-virus-spread modelling and the formulation of more effective pandemic countermeasures in transit-reliant cities. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/29063 2022-01-01T00:00:00Z https://hdl.handle.net/2123/28431 A Systematic Review on Technologies and Applications in Smart Campus: A Human-Centered Case Study Zhang, Yuchen; Yip, Christine; Lu, Erwan; Dong, Zhao Yang The smart revolution has penetrated in a wide range of applications. Smart campus, as the high-end form of education systems, deploys cutting-edge information and communication technologies to enhance the effectiveness and efficiency of campus services. Under the pandemic of COVID-19, smart campus has shown unprecedented importance owing to its remote, personalized, and ubiquitous features. All these factors have made smart campus an ongoing intense research topic in recent years, whereas existing reviews on smart campus were conducted in earlier years and thus an update is imperatively needed to investigate and summarize the emerging knowledge, technologies, and applications in this context. This paper conducts a systematic review on smart campus technologies and applications, and then strategically classifying them into different domains to investigate the current research pattern. Moreover, adhering to the human-centered principle of smart campus development, a human-centered case study has been carried out and presented in this paper to evaluate the consistency and adherence of current research trend to the stakeholders needs and interests. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/28431 2022-01-01T00:00:00Z https://hdl.handle.net/2123/28239 Suburban Road Networks to Explore COVID-19 Vulnerability and Severity Uddin, Shahadat; Khan, Arif; Lu, Haohui; Zhou, Fangyu; Karim, Shakir The Delta variant of COVID-19 has been found to be extremely difficult to contain worldwide. The complex dynamics of human mobility and the variable intensity of local outbreaks make measuring the factors of COVID-19 transmission a challenge. The inter-suburb road connection details provide a reliable proxy of the moving options for people between suburbs for a given region. By using such data from Greater Sydney, Australia, this study explored the impact of suburban road networks on two COVID-19-related outcomes measures. The first measure is COVID-19 vulnerability, which gives a low score to a more vulnerable suburb. A suburb is more vulnerable if it has the first COVID-19 case earlier and vice versa. The second measure is COVID-19 severity, which is proportionate to the number of COVID-19-positive cases for a suburb. To analyze the suburban road network, we considered four centrality measures (degree, closeness, betweenness and eigenvector) and core-periphery structure. We found that the degree centrality measure of the suburban road network was a strong and statistically significant predictor for both COVID-19 vulnerability and severity. Closeness centrality and eigenvector centrality were also statistically significant predictors for COVID-19 vulnerability and severity, respectively. The findings of this study could provide practical insights to stakeholders and policymakers to develop timely strategies and policies to prevent and contain any highly infectious pandemics, including the Delta variant of COVID-19. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/28239 2022-01-01T00:00:00Z https://hdl.handle.net/2123/27361 A census-based housing vulnerability index for typhoon hazards in the Philippines Healey, Sarah; Lloyd, Sophie; Gray, Jasmine; Opdyke, Aaron The Sendai Framework for Disaster Risk Reduction recognises housing as an important element of vulnerability, however, there remains limited understanding of how sub-national housing vulnerability varies spatially. This research sought to develop a municipal-level housing vulnerability index for typhoon hazards, applied at a national scale in the Philippines. We first selected 25 housing vulnerability indicators from the 2015 Philippines census, which were reduced into seven underlying dimensions of typhoon-related housing vulnerability using principal component analysis: housing density, housing quality, crowdedness, tenure security, extreme substandard housing, drinking water source, and structural integrity. These components were then aggregated to create a relative housing vulnerability index. We applied spatial clustering analysis to test for patterns, finding increasing housing vulnerability from north to south, with nuance in municipalities that defy these national trends. Our results offer a more granular view of housing vulnerability which may assist in unpacking how localised housing conditions contribute to disaster risk and assist researchers and government agencies in targeting disaster interventions. Sat, 01 Jan 2022 00:00:00 GMT https://hdl.handle.net/2123/27361 2022-01-01T00:00:00Z https://hdl.handle.net/2123/27306 Job and worker density and transit network dynamics Li, Manman; Cui, Mengying; Levinson, David M. This paper proposes a general framework to explore the interaction between land use and transport systems. Hypotheses about those relationships are generated. A series of statistical tests are conducted to explain the co-development of land use and transit networks for metropolitan areas at a micro-geographic scale and to disentangle causes and effects. The specific case of Minneapolis - Saint Paul (Twin Cities) metropolitan is examined using a panel of block-level land use and stop-level transit data. The results show that the development of land use, specifically, resident workers, can lead to the increase in bus demand, and thus further induce the increase in bus supply; the co-development of bus demand and supply is simultaneous on a yearly basis. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/27306 2021-01-01T00:00:00Z https://hdl.handle.net/2123/27305 Immigrant settlement patterns, transit accessibility, and transit use Allen, Jeff; Farber, Steven; Greaves, Stephen; Clinton, Geoffrey; Wu, Hao; Sarkar, Somwrita; Levinson, David M. Public transit is immensely important among recent immigrants for enabling daily travel and activity participation. The objective of this study is to examine whether immigrants settle in areas of high or low transit accessibility and how this affects transit mode share. This is analyzed via a comparison of two gateway cities: Sydney, Australia and Toronto, Canada. We find that in both cities, recent immigrants have greater levels of public transit accessibility, on average, compared to the overall population, but the geography of immigrant settlement is more suburbanized in Toronto than in Sydney. Secondly, using logistic regression models with spatial filters, we find significant positive relationships between immigrant settlement patterns and transit mode share, after controlling for transit accessibility and other socio-economic factors, indicating an increased reliance on public transit by recent immigrants. Via a sensitivity analysis, we find that these effects are greatest in peripheral suburbs and rural areas. These findings highlight the overall importance of providing public transit to immigrant communities, but transit usage by recent immigrants will vary regionally and depending on local neighbourhood context. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/27305 2021-01-01T00:00:00Z https://hdl.handle.net/2123/27304 An energy loss-based vehicular injury severity model Ji, Ang; Levinson, David M. How crashes translate into physical injuries remains controversial. Previous studies recommended a predictor, Delta-V, to describe the crash consequences in terms of mass and impact speed of vehicles in crashes. This study adopts a new factor, energy loss-based vehicular injury severity (ELVIS), to explain the effects of the energy absorption of two vehicles in a collision. This calibrated variable, which is fitted with regression-based and machine learning models, is compared with the widely-used Delta-V predictor. A multivariate ordered logistic regression with multiple classes is then estimated. The results align with the observation that heavy vehicles are more likely to have inherent protection and rigid structures, especially in the side direction, and so suffer less impact. Wed, 01 Jan 2020 00:00:00 GMT https://hdl.handle.net/2123/27304 2020-01-01T00:00:00Z https://hdl.handle.net/2123/27068 The application of industry 4.0 technologies in pandemic management: Literature review and case study Moosavi, Javid; Bakhshi, Javad; Martek, Igor The Covid-19 pandemic impact on people’s lives has been devastating. Around the world, people have been forced to stay home, resorting to the use of digital technologies in an effort to continue their life and work as best they can. Covid-19 has thus accelerated society’s digital transformation towards Industry 4.0 (the fourth industrial revolution). Using scientometric analysis, this study presents a systematic literature review of the themes within Industry 4.0. Thematic analysis reveals that the Internet of Things (IoT), Artificial Intelligence (AI), Cloud computing, Machine learning, Security, Big Data, Blockchain, Deep learning, Digitalization, and Cyber–physical system (CPS) to be the key technologies associated with Industry 4.0. Subsequently, a case study using Industry 4.0 technologies to manage the Covid-19 pandemic is discussed. In conclusion, Covid-19,is clearly shown to be an accelerant in the progression towards Industry 4.0. Moreover, the technologies of this digital transformation can be expected to be invoked in the management of future pandemics. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/27068 2021-01-01T00:00:00Z https://hdl.handle.net/2123/26916 Adoption of seismic-resistant techniques in reconstructed housing in the aftermath of Nepal’s 2015 Gorkha earthquake Hendriks, Eefje; Opdyke, Aaron Earthquake affected households too often insufficiently apply seismic construction knowledge during reconstruction. This study aims to assess to what degree safety guidelines have found their way to practice in Nepal. Differences are explored between communities in the Gorkha and Okhaldhunga districts, which received differing levels of technical assistance following the 2015 earthquakes. Seismic resistance of houses was assessed 3 years after the earthquakes. Findings from 955 houses in 25 communities show high degrees of adoption of earthquake-resistant construction knowledge in all selected communities. Variation in safer construction across communities differs only slightly for different intensities of humanitarian technical assistance. This finding points toward the need to more closely examine the communication methods employed and motivations of households to build back safer. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/26916 2021-01-01T00:00:00Z https://hdl.handle.net/2123/26890 Applications of Access Levinson, David M.; Ermagun, Alireza Striving to reflect on the significance and comprehensiveness of access applications, we collected 19 chapters covering access research in seven main categories to illustrate the state-of-the-art of access applications along distinct dimensions of transport studies. Our chapters cover access research at the international, national, metropolitan, and city levels. American cities are studied in chapter 3, chapter 4, chapter 11, chapter 14, chapter 16, chapter 18, and chapter 19. International cases are assessed and compared in chapter 2 and chapter 17, while chapter 9 examines Munich, Germany and chapter 13 analyzes Jakarta, Indonesia. Chapters are grouped into seven informal and overlapping categories: Equity and social justice: In chapter 2, Santos and Boisjoly discuss a series of case studies that display a growing concern for transport equity. They suggest that professionals and policymakers can adopt access-based approaches to foster social inclusion through equitable transport policies. In chapter 3, Palmateer and Levinson evaluate potential measures of distributive justice based on the access to jobs provided by various modes and offer recommendations for appropriate use of each measure. In chapter 4, Borowski, Ermagun, and Levinson explore the relation between transit-based job access and minority races and ethnicities, low- and middle-income households, and carless households at the block group level for the 50 most populated metropolitan areas in the United States. The analyses show that access is unevenly distributed across metropolitan regions across the US when considering various socio-demographic populations. Different metropolitan regions provide different levels of access for all investigated socio-demographic categories, whether considering racial minorities, levels of income, or car ownership. Resilience and crisis: In chapter 5, DeWeese, Manaugh, and El-Geneidy show how access can be used as a rapid diagnostic tool to assess the potential impacts of public transport service adjustments during a public health crisis. In chapter 6, Ghorbanzadeh, Kim, Ozguven, and Horner assess the spatial access of US census population block groups to congregate and non-congregate shelters in Northwest Florida. They argue that many areas in Northwest Florida have lower access to non-congregate shelters compared to congregate shelters. Active transport: In chapter 7, Murphy, Owen, and Levinson predict pedestrian activity using scalable and transferable predictive variables. They show that access to jobs by walking and transit, automobile traffic, and specific economic job categories (Education, Finance) are significant predictors of increased pedestrian traffic. In contrast, access to other economic job categories (Management, Utilities) significantly predict decreased pedestrian traffic. In chapter 8, Schoner and Levinson study people’s navigation from place to place using the Nice Ride Minnesota bikeshare system in Minneapolis. The results indicate people prefer to use stations that do not require long detours out of the way to access. However, commuters and non-work travelers differ in how they value the walking portion of their trip and what station amenities and neighborhood features increase a station’s utility. In chapter 9, Duran-Rodas, Nichols, and Büttner conducted a spatial fairness assessment to analyze which social groups are favored with active access to Urban E-commerce Infrastructure (UEI) in Munich and claim that e-commerce infrastructure benefits the cosmopolitan population, regardless of social status. Public transport: In chapter 10, Zeng, Song, and Chen present methods and procedures to evaluate grocery store spatio-temporal access considering coupled constraints of transit schedules and store opening hours. The findings suggest that decision-makers need to consider the variations in access levels across different spatial locations, times of the day, and social groups within various living-built environments. In chapter 11, Guthrie and Fan explore the ability of transit systems in regions to provide post-secondary education and job placement services destinations for marginalized workers. Their results provide compelling evidence for the social equity benefits of regional transit investments and the importance of integrated transit, land use, and regional public service planning. Auto travel: In chapter 12, Huang and Levinson examine the impact of land use around the home on vehicle trip generation and identify the correlation of trips made by the same individual in the trip generation models. The results indicate that although access around the home is not found to have statistically significant effects on non-work vehicle trips, the diversity of services within 10 to 15 minutes and 15 to 20 minutes from home can help reduce the number of non-work vehicle trips. In chapter 13, Andani, Paix, Rachmat, Syabri, and Geurs describe an evaluation of the job access and spatial equity impacts of the Cipularang toll road in the Jakarta – Bandung corridor in Indonesia. The analysis reveals that the construction of the toll road has reduced travel time in the whole region by 13%, and potential job access increased by 5%. System performance: In chapter 14, Ermagun and Levinson disentangle the impacts of financial and physical dimensions of transit service operators on net transit access. The results indicate that using the same operating expenses for both bus and train services, the bus system provides roughly 6 times more access than the train system. The bus system also operates 4 times more efficiently than the train system, providing access with the same frequency. In chapter 15, Iacono, Cao, Cui, and Levinson investigate the relation between urban access and firm agglomeration, as reflected in patterns of employment densities. They argue that urbanization effects tend to overshadow those of localization effects. These effects vary by sector, with many service-based sectors showing a stronger propensity to agglomerate than manufacturing and several “basic” sectors like agriculture, mining, and utilities. In chapter 16, Janatabadi, Tajik, and Ermagun study the spatial and temporal disparity of modal access to employment in Chicago and its nine neighborhoods. The findings alert urban planners and policymakers on the effects of travel time and space on access analysis. They also explain how inaccurate perceptions of transit performance prevent the development of an effective and equitable transit system. Project evaluation: In chapter 17, Stewart and Byrd evaluate how interactive tools for calculating and visualizing indicators of access to opportunities can facilitate more integrated metropolitan planning. In chapter 18, Palmateer, Ermagun, Owen, and Levinson examine the importance of service area definition when utilizing access-based evaluation in transit projects. The results indicate that the choice of transit service areas significantly impacts the value of absolute access measures. In chapter 19, Palmateer, Owen, and Ermagun use the access-based evaluation method to unpack the interaction effect of transit-oriented development and a new transit hub using the San Francisco Transbay Transit Center Development Plan project. This indicates that in areas where there already is transit service, the development of land near the transit service can have a greater impact on access levels than the improvement of connections between transit services. The book ends in chapter 20 with a review by Jin, Cheng, and Witlox of how virtual access interacts with physical access and how the interaction affects travel-access relations in the future. Mon, 15 Nov 2021 00:00:00 GMT https://hdl.handle.net/2123/26890 2021-11-15T00:00:00Z https://hdl.handle.net/2123/26118 COVID-19, Travel Time Reliability, and the Emergence of a Double-Humped Peak Period Gao, Yang; Levinson, David M. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/26118 2021-01-01T00:00:00Z https://hdl.handle.net/2123/25031.4 Approximate Analysis of Non-Uniform Torsion (No. R968) Trahair, Nicholas S.; Papangelis, John It is difficult to obtain closed form exact solutions for the non-uniform torsion of beams. Advanced finite element methods easily produce very accurate solutions, but simple programs are not widely available. One simple program is validated by comparing its solutions with closed form solutions. A simple approximate method is proposed which combines the uniform and warping torsion stiffness approximations. The determination of the warping stiffness approximation is simplified by using the moment-area method. The approximate twist rotations are compared with the accurate solutions, are shown to be of generally acceptable accuracy, and in most cases to be conservative. Approximate solutions for the central twist rotations of simply supported beams with off-centre torques can be combined using superposition to find solutions for a wide range of torque loadings. A worked example is given. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/25031.4 2021-01-01T00:00:00Z https://hdl.handle.net/2123/25844 Erosion of bed materials in lab-scale flume experiments of dry glass beads Dulanjalee, Eranga; Guillard, François; Baker, James; Einav, Itai; Marks, Benjy A set of dynamic radiographs of the flow of glass beads over an erodible bed. The data has been recorded from one or two directions, and for eight separate experiments, each with different combinations of grain size in the flowing and erodible material. Tue, 10 Aug 2021 00:00:00 GMT https://hdl.handle.net/2123/25844 2021-08-10T00:00:00Z https://hdl.handle.net/2123/25813 Prioritising Build Back Safer Messages for Humanitarian Shelter Opdyke, Aaron; Wang, Zhenwen Humanitarian shelter assistance increasingly employs build back safer messages as a technical assistance tool to disaster-affected communities. We sought to prioritise the importance of key messages for small, light-weight timber shelter using a combination of Delphi and Analytical Hierarchy Process (AHP) methods. A panel of twelve academic and practitioner experts were asked to rank build back safer messages developed in the Philippines after Typhoon Haiyan in 2013 which have formed the basis for subsequent humanitarian messages in the Asia-Pacific region. Findings revealed three groups of shelter key messages by importance: (1) bracing and joints, (2) foundations, tie-downs, and roofing and (3) shape. However, there was low consensus among panellists in their judgements of these overall comparisons. The individual structural components used in guidance within each message were also ranked with high consensus among panellists. Our results were consistent with the original message ordering, but expert judgements revealed differing relative structural capacities between components. The resulting numerical weightings and rankings offer clearer guidance on the relative importance of different groups of build back safer messages for non-engineered shelter and housing in low- and middle-income countries. Results may help humanitarian agencies create more targeted messaging to support safer and more durable shelter. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/25813 2021-01-01T00:00:00Z https://hdl.handle.net/2123/25559 Generalised component method-based finite element analysis of steel frames (No. R969) Rasmussen, Kim; Yan, S This report presents a new analysis approach that incorporates macro-element joint models based on the Generalised Component Method in the FE analysis of steel frame buildings. The new analysis approach is termed Generalised Component Method-based finite-element (GCM-FE) analysis. The fundamental aspects and principles of the GCM-FE analysis approach are established in this report, including the framework of GCM-FE analysis, the constitutive models for the connection components and the implementation of GCM-FE analysis in commercial numerical software including an automatic modelling technique. The GCM-FE joint modelling method is first validated against the experimental results of three steel beam-to-column connection types, including the bolted moment end-plate connection, top-and-seat angle connection and web angle connection. GCM-FE analysis is subsequently performed on a two-storey four-bay irregular steel frame, showing apparent advantages over the traditional analysis methods which adopt simplified joint models. The GCM-FE analysis not only provides the ultimate resistance and failure mode of the frame, but also accurately predicts the load-redistribution process inside the connections and the resultant effect on the structural framework. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/25559 2021-01-01T00:00:00Z https://hdl.handle.net/2123/24069.2 The Shift of the Effective Centroid in Plain Channel Section Columns (No. R966) Arrayago, Itsaso; Rasmussen, Kim J.R. The report derives an equation for the shift of the effective centroid that occurs in plain channel section columns as a result of local buckling. The shift causes bending when the column is compressed between pinned ends and may need to be accounted for in design. The equation is based on Stowell’s work on simply supported plate elements with a free longitudinal edge. It is shown to be in reasonable agreement with eccentricities calculated using results of geometric nonlinear shell finite element analyses of plain channel columns. It is also shown to provide more accurate values of eccentricity than the effective width method, in which the effective width of each plate element is calculated to produce an effective cross-section and an associated effective centroid. Wed, 01 Jan 2020 00:00:00 GMT https://hdl.handle.net/2123/24069.2 2020-01-01T00:00:00Z https://hdl.handle.net/2123/24084.3 The Mechanics of Built-Up Cold-Formed Steel Members (No. R965) Rasmussen, Kim J.R.; Khezri, Mani; Schafer, Benjamin W.; Zhang, Hao The paper presents methods of analysis of built-up sections in which the discrete locations of fasteners is accounted for explicitly, rather than by smearing their effect using continuous shear flexibility as in current approaches. By considering fasteners at discrete points, it is possible to analyse the effects of placing additional fasteners at the ends (end fastener groups), to account directly for actual support conditions and to determine the optimum locations of fasteners. The paper first outlines the linear analysis of beams in flexure and introduces the notion of the effective flexural rigidity to account for partial composite actions. Closed form solutions are provided for five load and end support cases to demonstrate the application of the analysis. Next, the paper describes the linear analysis of built-up sections in torsion, considering first uniform torsion followed by non-uniform torsion. Closed form solutions are obtained for the effective torsion rigidity (GJeff) of built-up sections featuring closed loops. A framework is also presented for determining the effective torsion rigidity (EIw,eff) of open built-up sections in non-uniform torsion. The paper concludes with the analysis of built-up sections subject to flexural buckling. A general variational buckling equation is derived followed by an energy type method for calculating buckling loads for common end support conditions, including columns supported on flexible end tracks. Closed form solutions are presented for up to seven rows of fasteners longitudinally. While by nature approximate, the solutions are shown to be highly accurate. Comparisons are made between the presented closed form solutions and buckling load predictions obtained using current design provisions. Tue, 01 Jan 2019 00:00:00 GMT https://hdl.handle.net/2123/24084.3 2019-01-01T00:00:00Z https://hdl.handle.net/2123/24411.2 Limit States Design of Crane Runway Girders: Research Report R967 Trahair, Nicholas S. Steel crane runway girders are subjected to torsion by their eccentric loads. The twist rotation of the principal axes caused by torsion induces additional bending moments, and reduces the resistance to lateral buckling. There is little guidance on how to design for torsion, and design procedures are often intuitive, with varying degrees of rationality and precision. This paper seeks to establish a logical procedure for designing crane runway girders which is based on an extension of the limit states methods of designing for biaxial bending. An additional term for the ratio of the design torque to the section torsion resistance is included in the interaction equations. Proposals are made for determining this section resistance. Research has shown that this addition can allow for the reduction in the lateral buckling resistance caused by the twist rotations. A linear elastic analysis of the twist rotations is used to determine the moment increases caused by torsion. An example of the proposed method is developed and illustrated by a design example. The small twist rotations are not enough to have a major effect on the bending moments. The additional torsion term is also small, and the design capacity is primarily governed by the resistance to lateral buckling. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/24411.2 2021-01-01T00:00:00Z https://hdl.handle.net/2123/25371 Dataset for "Characterisation of fracture evolution of a single cemented brittle grain using in-situ X-ray computed tomography" Jiang, Sheng; Shen, Luming; Guillard, François; Einav, Itai This dataset is corrrsponding to the tests in the journal paper 'Characterisation of fracture evolution of a single cemented brittle grain using in-situ X-ray computed tomography'. The dataset of this study should also help significantly numerical modelers seeking to evaluate their models. The experimental observations of the fracture process of single cemented grains, particularly the temporal 3D data, can be considered and incorporated into the development of future constitutive models for more sophisticated modeling of material failure. Meanwhile, the whole experimental fracture evolution can be treated for valuable training and testing data for machine learning in order to better predict the fracture propagation. This dataset contains the CT images for the fragmentation process of a single brittle glass bead cemented by ductile epoxy resin, along with the correspionding force-displacement curves. Wed, 02 Jun 2021 00:00:00 GMT https://hdl.handle.net/2123/25371 2021-06-02T00:00:00Z https://hdl.handle.net/2123/25081 A List of Papers in the Journal 'Findings'. Levinson, David M. This research note compiles a list of papers published in the journal Findings, in alphabetical order by the last name of the first author. The list is in the References. Each article also has its Digital Object Identifier. Wed, 19 May 2021 00:00:00 GMT https://hdl.handle.net/2123/25081 2021-05-19T00:00:00Z https://hdl.handle.net/2123/24279 Defining a Humanitarian Shelter and Settlements Research Agenda Opdyke, Aaron; Goldwyn, Briar; Javernick-Will, Amy Despite the knowledge gained on post-disaster sheltering and housing over the last several decades, there remains a disconnect in the evidence needed by humanitarian practitioners and the learning that the research community is capturing. To determine the research needed by practitioners, we assembled a Delphi panel of experts in humanitarian shelter and settlements. They first identified and then ranked the relative importance of research topics. Ninety-six research needs were identified and ranked by importance in six key areas that included: (1) comparing and evaluating approaches to sheltering, (2) shelter and settlement programming, (3) design and construction of shelter, (4) understanding impacts and outcomes of shelter, (5) disaster risk reduction and the humanitarian-development nexus, and (6) challenging contexts and topics. Top research priorities identified include a need to better understand how to support shelter self-recovery, longitudinal and long-term impacts of shelter, and the transition from response to recovery. The resulting needs provide a research agenda for humanitarian organizations, academic institutions, and donors, aligning with the Global Shelter Cluster's strategy to invest in evidence-based response. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/24279 2021-01-01T00:00:00Z https://hdl.handle.net/2123/24142 Mitigating Infrastructure Disaster Losses Through Asset Management Practices in the Middle East and North Africa Region Mastroianni, Elyssa; Lancaster, James; Korkmann, Benjamin; Opdyke, Aaron; Beitelmal, Wesam Despite expanding infrastructure investments in developing countries, maintenance of constructed infrastructure is not keeping pace and there is a growing need to focus on the long-term operational demands of new assets to reduce vulnerability. In the Middle East and North Africa (MENA) region, natural hazards and civil conflicts continue to undermine development and disaster risk management. This research sought to examine how infrastructure asset management can reduce the impact of disasters in the MENA region. Twelve interviews were conducted with asset management and disaster risk reduction experts in the MENA region and Australia – the latter to identify transferable asset management best practices. Qualitative analysis of interviews identified regional lessons to advance asset management practice as a disaster risk reduction tool. The four main findings were: (1) asset management practice can be a proactive disaster policy; (2) there is need for appropriate levels asset management policy in the MENA region; (3) asset prioritisation improves the effectiveness of, and decision making in, risk management; and (4) whole of life consideration enables effective planning for asset management practices. In alignment with the priorities of the Sendai Framework for Disaster Risk Reduction, this research provides knowledge to strengthen governance to manage disaster risk in the MENA region. The research further outlines the barriers and challenges that hinder successful asset management policy implementation, as well as proposes recommendations for disaster mitigation strategies using infrastructure asset management. Fri, 01 Jan 2021 00:00:00 GMT https://hdl.handle.net/2123/24142 2021-01-01T00:00:00Z https://hdl.handle.net/2123/24075 Stress-Strain Model for Ferritic Stainless Steels (No. R953) Tao, Zhong; Rasmussen, Kim J.R. Compared with austenitic or duplex stainless steels, ferritic stainless steels have no or very low nickel content. Therefore, their cost is lower and more stable than those of austenitic and duplex stainless steels, providing a more viable alternative for structural applications. Existing stress−strain models, however, are less accurate in predicting stress−strain curves of ferritic stainless steels than for austenitic and duplex stainless steels, since ferritic stainless steels behave more similarly to plain carbon steel. A wide range of tensile test data were collected for ferritic stainless steel coupons, either cut from steel sheets or cold-formed hollow sections. Using the three basic Ramberg-Osgood parameters, stress−strain models are developed for both flat and corner ferritic stainless steels. The accuracy of the proposed models is verified by comparing their predictions with experimental stress−strain curves. Thu, 01 Jan 2015 00:00:00 GMT https://hdl.handle.net/2123/24075 2015-01-01T00:00:00Z https://hdl.handle.net/2123/24082 Torsion Equations for Lateral Buckling (No. R964) Trahair, Nicholas S. A torsion differential equation previously used for analysing the elastic lateral buckling of simply supported doubly symmetric beams with distributed loads acting away from the centroidal axis omits an expected term and includes an unexpected term. A different equation is derived by two different methods, either by using the calculus of variations with the second variation of the total potential, or by considering the equilibrium of the deflected and twisted beam. Four different methods are used to find solutions for the elastic buckling of beams with uniformly distributed loads. Two of these solve the differential equations numerically, either by using a computer program based on the method of finite integrals, or by making hand calculations with a single term approximation of the buckled shape. These methods produce different solutions for the two torsion differential equations. The two other methods used are based on the energy equation for lateral buckling. The first of these uses hand calculations and a limited series for the buckled shape, while the second uses a finite element computer program based on cubic deformation fields. Both of these produce solutions which agree closely with the finite integral and approximate solutions for the different differential equation derived in this paper, but are markedly different from the solutions for the previously used equation. It is concluded that the previously used torsion differential equation is in error. Fri, 01 Jan 2016 00:00:00 GMT https://hdl.handle.net/2123/24082 2016-01-01T00:00:00Z https://hdl.handle.net/2123/24076 A General-Purpose Multiphase and Multicomponent Computational Solver for Biogeochemical Reaction-Advection-Dispersion Processes in Porous and Non-Porous Media (No. R954) Maggi, Federico Abstract This document describes the functioning principles and practical use of BRTSim framework at its version 1 stage of development. BRTSim (BioReactive Transport Simulator) is a general‐purpose multiphase and multicomponent computational solver for biogeochemical reaction‐advection‐dispersion processes in porous and non‐porous media. BRTSim finds suitable applications to describe water flow in soils and geophysical media, to track transport and dispersion of aqueous and gaseous chemicals, as well as to assess their chemical equilibrium and their decomposition rates in both chemical and biochemical reactions. For these characteristics, BRTSim is an extraordinary computational tool in soil physics and biogeochemistry, soil and water quality assessment and prediction, soil bio‐ and phyto‐remediation potential estimation, and in all environmental engineering contexts where physical, chemical and biological processes co‐exist and affect each other with complex nonlinear feedbacks. BRTSim allows defining a geophysical domain with an arbitrary number of grid elements nodes that may be heterogeneous in their physical and hydraulic properties; BRTSim allows full control of initial and boundary conditions, and allows defining a biogeochemical system with an arbitrary number of primary aqueous species, secondary aqueous species, gaseous and mineral species (in chemical equilibrium with primary species), and biological microbial functional groups with any specific metabolic requirement. Chemical and biochemical reactions can be defined for any kinetics framework and order. BRTSim version 1 bases on solvers that have been largely tested, but because of its potentiality, it is under continuing development and improvement in numerical accuracy, robustness, reliability, and computational performance. It is to be noted that, although all methods used to solve physical and chemical processes follow recommendations and methods largely accepted in the scientific literature, the integration of diverse processes, each one requiring time scales that may largely vary from any other, may have potential defects. BRTSim, as a consequence, is also a platform where newly developed algorithms are implemented and tested to improve older and less performing algorithms. Iteration number and tolerances can be set for the various processes but it is practically impossible to exhaustively cross‐check mutual compatibility. The BRTSim framework is therefore designed to allow the user to correct potential instabilities, which depend on the specific problem to be solved, and set the numerical solvers to converge by criteria with an arbitrary level of accuracy. Thu, 01 Jan 2015 00:00:00 GMT https://hdl.handle.net/2123/24076 2015-01-01T00:00:00Z https://hdl.handle.net/2123/24073 A Laboratory Facility for Flocculation-Related Experiments (No. R952) Tang, Fiona H.M.; Maggi, Federico This report describes the design and functions of a new experimental facility built in the School of Civil Engineering at the University of Sydney used for the investigation of flocculation-related processes. This facility was uniquely designed to replicate physical (hydrodynamic processes and sediment load), chemical (nutrients and contaminants) and biological (micro-organisms) processes in natural aqueous environment; hence, it allows for investigating the effects of these processes on the flocculation dynamics of suspended particle matter (SPM) through a fully controllable laboratory-based research. It consists of five major components, including a smallscale settling column, a turbulence generating system, a water quality mea-suring system, a μPIV system, and a micro-controlling system. Measurements, either imaging data of settling SPM or water quality readings, can be acquired automatically with any ar-bitrary scheduling. The innovation of this facility is the integration of physical, chemical and biological aquatic processes into one framework to explore the complexity of the interactions be-tween these processes and SPM dynamics. One of its major contributions to the advancement in sediment dynamics studies is the direct detection of possible repercussions the increased anthropogenic stresses has on the microbial population and the aggregation kinematics and statistics of suspended particles in aqueous ecosystem. Ultimately, this facility is expected to contribute to a comprehensive understanding of how all possible interactions in natural water bodies affect each other and consequently, how these interactions affect SPM flocculation and transport. Thu, 01 Jan 2015 00:00:00 GMT https://hdl.handle.net/2123/24073 2015-01-01T00:00:00Z https://hdl.handle.net/2123/24079 Formulation and Implementation of General Thin-Walled Open-Section Beam-Column Elements in Opensees (No. R961) Rinchen; Hancock, Gregory J.; Rasmussen, Kim J.R. The formulation and implementation of beam-column finite elements for the general thin-walled open cross-sections within the OpenSees framework is presented. To account for the non-coincident location of shear centre and centroid as is the case in non-symmetric sections, a local cross-section transformation matrix is derived relating the axial force acting through the centroid and the shear centre. The stiffness relations are derived based on the Green-Lagrange strain for the displacement based beam-column element while the Wagner effect is incorporated in the torsional rigidity term for the elastic beam-column element. The beam-column elements are then implemented within the corotational framework of OpenSees. The performance of developed beam-column elements are demonstrated through the use of monosymmetric, doubly-symmetric and asymmetric sections in a series of numerical examples. The solutions obtained are verified with the results from the beam and shell element models in ABAQUS software. Fri, 01 Jan 2016 00:00:00 GMT https://hdl.handle.net/2123/24079 2016-01-01T00:00:00Z https://hdl.handle.net/2123/24081 The Generalised Constrained Finite Strip Method for Thin-Walled, Prismatic Members Under Applied Shear (No. R963) Rendall, Morgan A.; Hancock, Gregory J.; Rasmussen, Kim J.R. The constrained finite strip method (cFSM) is an extension of the semi-analytical finite strip method (SAFSM) of structural analysis of thin-walled members, where consideration of the displacement fields utilised and of various mechanical criteria allows constraint matrices to be formed. The application of these constraint matrices to the linear buckling eigenvalue problem of the SAFSM results in deformation fields that satisfy the considered criteria and, therefore, isolate particular modes. Through careful selection of the mechanical criteria, the deformation fields obtained may be restricted to particular buckling modes. This is referred to as modal decomposition. While the cFSM has been applied to modal decomposition of thin-walled, prismatic members under the action of longitudinal normal stresses, it has yet to be applied to such members under the action of shear stresses. Recent work using the SAFSM to analyse the buckling behaviour of thin-walled, prismatic members under applied shear stresses, notably by Hancock and Pham, has shown that the issues of potentially indistinct minima or multiple minima in the signature curve can occur under this loading, as they did for compression and bending. This paper briefly presents the derivation of a SAFSM that permits coupling between longitudinal series terms of sines and cosines and also considers membrane instability due both to shear stresses and transverse normal stresses. It then presents the application of the cFSM to such a finite strip and results are produced for members under shear stresses. While the results are presented for members with unrestrained ends (equivalent to infinitely long members with simply-supported ends), simplification via removal of the degrees of freedom not present in typical FSM formulations would allow finite length members with simply-supported ends to be analysed. Fri, 01 Jan 2016 00:00:00 GMT https://hdl.handle.net/2123/24081 2016-01-01T00:00:00Z https://hdl.handle.net/2123/24078 In-Plane Behaviour of Web-Tapered Beams (No. R956) Trahair, Nicholas S.; Ansourian, P. Shear stress distributions in tapered web I-beams are incorrectly predicted by the conventional beam analysis method used for uniform beams. More accurate predictions are obtained by adopting the finding for wedges that the normal stress trajectories are radial instead of parallel. The shear stress distributions in web-tapered I-beams are influenced by the vertical components of the inclined flange forces (which are zero in uniform beams), as well as by the normal stress gradients in the flanges. The net web shear equal to the difference between the external shear and the vertical components of the inclined flange forces is resisted by the resultant of the vertical components of the normal stresses and the circumferential shear stresses. The circumferential shear stresses have linear components due to axial force and parabolic components due to moment and shear. The magnitudes of these stresses are controlled by the normal stress gradients at the flange-web junctions and by the requirement that the web shear resistance must equal the net web shear force. Thu, 01 Jan 2015 00:00:00 GMT https://hdl.handle.net/2123/24078 2015-01-01T00:00:00Z