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1.	Sundell, Jonas, 1984, et al. (författare) Comprehensive risk assessment of groundwater drawdown induced subsidence 2019 Ingår i: Stochastic Environmental Research and Risk Assessment. - : Springer Science and Business Media LLC. - 1436-3240 .- 1436-3259. ; 33:2, s. 427-449 Tidskriftsartikel (refereegranskat)abstract © 2019, The Author(s). We present a method for risk assessment of groundwater drawdown induced land subsidence when planning for sub-surface infrastructure. Since groundwater drawdown and related subsidence can occur at large distances from the points of inflow, the large spatial extent often implies heterogeneous geological conditions that cannot be described in complete detail. This calls for estimation of uncertainties in all components of the cause-effect chain with probabilistic methods. In this study, we couple four probabilistic methods into a comprehensive model for economic risk quantification: a geostatistical soil-stratification model, an inverse calibrated groundwater model, an elasto-plastic subsidence model, and a model describing the resulting damages and costs on individual buildings and constructions. Groundwater head measurements, hydraulic tests, statistical analyses of stratification and soil properties and an inventory of buildings are inputs to the models. In the coupled method, different design alternatives for risk reduction measures are evaluated. Integration of probabilities and damage costs result in an economic risk estimate for each alternative. Compared with the risk for a reference alternative, the best prior alternative is identified as the alternative with the highest expected net benefit. The results include spatial probabilistic risk estimates for each alternative where areas with significant risk are distinguished from low-risk areas. The efficiency and usefulness of this modelling approach as a tool for communication to stakeholders, decision support for prioritization of risk reducing measures, and identification of the need for further investigations and monitoring are demonstrated with a case study of a planned railway tunnel in Varberg, Sweden.
2.	Sundell, Jonas, 1984, et al. (författare) Economic valuation of hydrogeological information when managing groundwater drawdown 2019 Ingår i: Hydrogeology Journal. - : Springer Science and Business Media LLC. - 1431-2174 .- 1435-0157. ; 27:4, s. 1111-1130 Tidskriftsartikel (refereegranskat)abstract © 2019, The Author(s). A procedure is presented for valuation of information analysis (VOIA) to determine the need for additional information when assessing the effect of several design alternatives to manage future disturbances in hydrogeological systems. When planning for groundwater extraction and drawdown in areas where risks—such as land subsidence, wells running dry and drainage of streams and wetlands—are present, the need for risk-reducing safety measures must be carefully evaluated and managed. The heterogeneity of the subsurface calls for an assessment of trade-offs between the benefits of additional information to reduce the risk of erroneous decisions and the cost of collecting this information. A method is suggested that combines existing procedures for inverse probabilistic groundwater modelling with a novel method for VOIA. The method results in (1) a prior analysis where uncertainties regarding the efficiency of safety measures are estimated, and (2) a pre-posterior analysis, where the benefits of expected uncertainty reduction deriving from additional information are compared with the costs for obtaining this information. In comparison with existing approaches for VOIA, the method can assess multiple design alternatives, use hydrogeological parameters as proxies for failure, and produce spatially distributed VOIA maps. The method is demonstrated for a case study of a planned tunnel in Stockholm, Sweden, where additional investigations produce a low number of benefits as a result of low failure rates for the studied alternatives and a cause-effect chain where the resulting failure probability is more dependent on interactions within the whole system rather than on specific features.
3.	Dymitrow, Mirek, et al. (författare) Crossing dichotomies and breaking mental patterns: Green business development when all else fails? 2017 Ingår i: 8th International Scientific Conference “Rural Development 2017: Bioeconomy Challenges”, 23–24 November, 2017 Kaunas, Lithuania. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Obtaining sustainable and inclusive societal organization is not merely a simple matter of ‘doing it’ by subscribing to some winning formula. Given that conceptual frameworks always guide our thoughts, judgments and actions (Latour, 2013; Harvey, 1996; Dennett, 1993), the ways in which we relate to concepts chosen to serve as guiding forces for future development will eventually determine its outcome. As scholarly evidence continuously suggests the concepts ‘rural’ and ‘urban’ are increasingly recognized as artificial barriers for conducting sound and integrated development endeavors in a globalized reality of interconnectedness. In line with the Sustainable Development Goals, which aim to eradicate poverty, shield the planet and safeguard prosperity for all, commitment to universal access to healthy food year round has become an important agenda point. This, however, has been exacerbated by binary thinking and separate ways of doing policy. This paper aims to share experiences from a unique project launched in the northern parts of Gothenburg, Sweden’s second largest city. While the area offers ample resources and immense opportunities for areal economies, it at the same time remains one of Gothenburg’s most segregated, with high levels of unemployment, ill health and crime. The uniqueness of the project lies not only in its way of abridging the rural-urban divide, but also by consciously deferring from the debilitating rhetoric of previous ‘immigrant policies’, and instead focusing on agricultural productivity, small-scale food producers and sustainable food strategies. Such exhortations to bridge between philosophical and material polarities, however, have not come without conceptual and practical challenges, something this paper aims to subsume and open up to debate.
4.	Adl-Zarrabi, Bijan, 1959, et al. (författare) Safe and Sustainable Coastal Highway Route E39 2016 Ingår i: Transportation Research Procedia. - : Elsevier BV. - 2352-1465 .- 2352-1457. ; 14, s. 3350-3359 Konferensbidrag (refereegranskat)abstract The project “Coastal Highway Route E39” have a mandate to, investigate how infrastructure can exploit renewable energy to reduce environmental footprint. Three PhD projects were initiated on this subject at Chalmers University of Technology by Norwegian public road administration. Results in this paper conclude that (1) Life Cycle Assessment should have a geographical dimension with respect to assumptions and input data, (2) there are substantial potential to reduce the CO2 emissions from the E39, especially when considering an electrification, and (3) the harvested energy from hydronic pavement system can be enough for maintaining ice-free roads in Nordic countries.
5.	Aygül, Mustafa, 1970, et al. (författare) A comparative study of different fatigue failure assessments of welded bridge details 2013 Ingår i: International Journal of Fatigue. - : Elsevier BV. - 0142-1123. ; 49:0, s. 62-72 Tidskriftsartikel (refereegranskat)abstract Five different welded joints frequently used in steel bridges have been selected to investigate the accuracy and applicability of three fatigue assessment methods. The first method, also categorised as the global method, is the nominal stress method, while the more advanced methods are the hot spot and the effective notch stress methods. Solid element based finite element models for welded bridge details were created by following the modelling requirements of each fatigue assessment method. A statistical evaluation based on the results of the finite element analyses and the fatigue test data collected from the literature was performed to determine the mean and characteristic fatigue strength. In addition, the standard deviation for each data series was also determined to conclude how well each method describes the fatigue strength of each welded detail. A method with a lower standard deviation is regarded as more accurate. Moreover, the evaluated results from each method were compared with the recommended fatigue strength values in the Eurocode 3 (EN 1993-1-9:2005) and IIW codes. In the light of the test results in this study, it appears that the codes are in reasonable agreement with the test data, even though a few examples of the opposite occurred. The conclusion based on the revised results in this article indicates that the nominal stress method yields satisfactory results, despite its simplicity. When considering the effort involved in creating FE models for numerical analysis, it seems clear that the choice of the nominal method is fairly acceptable.
6.	Blomfors, Martin, et al. (författare) Reliability analysis of corroded reinforced concrete beam with regards to anchorage failure 2019 Ingår i: Life-Cycle Analysis and Assessment in Civil Engineering. - : CRC Press/Balkema. - 9781138626331 - 9781351857574 ; , s. 337-344, s. 337-344 Konferensbidrag (refereegranskat)abstract Reinforcement corrosion is a common problem in reinforced concrete infrastructure today, and it is expected to increase in the future. To simply replace the corroded structures with new ones requires large resources, both in financial and environmental terms. Therefore it is important that existing structures are used to their full potential, also after the onset of corrosion. This paper presents a reliability study of the anchorage capacity of a reinforced concrete beam including reinforcement corrosion. The sensitivity of the different input parameters is also studied. As expected, the results show that the reliability is reduced with corrosion; the magnitude depends to a large extent on the modelling uncertainty used for the bond model for corroded reinforcement. The sensitivity analysis shows an influence of corrosion also on the sensitivities of the input parameters, which is expected based on the properties of the underlying bond model. This paper demonstrates that probabilistic evaluations give valuable insight of the reliability, which can be used to prolong the service-life of existing infrastructure and save both money and the environment.
7.	Thunberg, Micael, 1986-, et al. (författare) Categorising on-site problems : A supply chain management perspective on construction projects 2017 Ingår i: Construction Innovation. - : Emerald Group Publishing Limited. - 1471-4175 .- 1477-0857. ; 17:1, s. 90-111 Tidskriftsartikel (refereegranskat)abstract Purpose - This study aims to identify and categorise common on-site problems from a supply chain management (SCM) perspective and to trace the origin of these problems in the construction project process, the supply chain or in the intersection between these processes. This allows for identification of how on-site problems affect SCM in construction projects and how they can be mitigated. Design/methodology/approach - A literature review in combination with semi-structured interviews was used to identify on-site problems. This enabled triangulation and strengthened both construct validity and internal validity. Findings - On-site problems can be categorised in one of the four following categories: material flows, internal communication, external communication or complexity. The first category has its origin in the supply chain, the second in the construction project process, the third in the supply chain-construction process intersection on site and the fourth in the construction project as a whole. The findings conclude that on-site problems often originate from construction companies' lack of supply chain orientation. Research limitations/implications - It is suggested that supply chain planning (SCP) can facilitate on-site problem mitigation in construction project management. This extends the body of knowledge of SCP in construction project management and supports the development of effective on-site construction project management. Practical implications - The results show that SCP can aid construction project management in handling on-site problems earlier in the project process. Originality/value - The main value lies in extending the body of knowledge in construction project management research by applying an SCM perspective and by introducing SCP to support more effective construction project management.
8.	Stojanovski, Todor, 1976- (författare) The Morphological Effect of Public Transportation Systems on Cities : Urban Analysis of Transit-Oriented Development (TOD) in Swedish Cities 2015 Konferensbidrag (övrigt vetenskapligt/konstnärligt)
9.	Ståhle, Alexander, et al. (författare) Designguide för Smarta gator 2022 Bok (övrigt vetenskapligt/konstnärligt)abstract Designguiden för smarta gator konkretiserar hur de fyra megatrenderna urbanisering, digitalisering, samhällsförändringar och miljöförändringar leder till nya krav och utformningsprinciper för framtidens gator. Guiden är tänkt att fungera som en inspiration och ett underlag för att förnya svensk gatupolicy på nationell, regional och kommunal nivå.Guiden innehåller utöver en inledning följande kapitel: en historisk tillbakablick (gatans utveckling), gatans användning, gatans delar, gatans design, designprocessen, guidens genomförande.
10.	Estévez Mauriz, Laura, 1982 (författare) The urban form and the sound environment - Tools and approaches 2017 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Cities are always confronted with transition and adaptation. Awareness on urban environmental quality is leading the vision about the built environment’s resilience and sustainability, highlighting the importance of a multidisciplinary framework for urbanisation processes. One of the main concerns is the negative impact of outdoor noise due to road traffic, whereby controlling the sound environment through good quality spatial production is a priority. Europe and other parts of the world are experiencing a chronic traffic congestion problem. The environmental impact of this situation is overwhelming, where 90 % of the health impact due to noise exposure is estimated to be caused by road traffic noise. In this regard, noise maps are seen as a powerful tool in the development of new urban areas, where its noise level underestimation can endanger the wellbeing of citizens. At this rapid urbanisation, divided pronouncements on decision-making are devastating. The aim is to overcome negative aspects derived from a late intervention by including urban sound planning as an opportunity to the user’s experience and wellbeing, avoiding poor patches in the urban configuration and economical burden. The present work is committed to the development of tools for controlling, communicating and designing the sound environment on a level beyond today’s solutions, capable to be included at the early stages of the planning process. First, the study goes through the importance of the quiet side and the implementation of an engineering method as a powerful tool in the urban development, obtaining accurate results compared to measurements. In an attempt to study time variations of traffic within cities and its relevance regarding noise emission (normally overlooked in current noise mapping calculations), a microscopic road traffic modelling tool is developed in the second study, giving useful output for noise level predictions as function of time. The time-pattern analysis opens the possibility to test traffic configurations and explore a large variety of results in the form of descriptors as statistical indicators, calm periods and noise events, and outcomes as difference maps and contribution maps. The third study extends toward the evaluation of the effects of spatial heterogeneity (considered a key strategy to increase the liveability of spaces) on the environmental performance and resilience capacity of the transportation system through the study of noise pollution and its economic impact. The studies presented are using real case scenarios as a test-bed not only for implementation, but mainly for the development of tools.
11.	Kickert, Conrad Christiaan, et al. (författare) Surveying density, urban characteristics, and development capacity of station areas in the Delta Metropolis 2014 Ingår i: Environment and Planning B: Planning and Design. - : SAGE Publications. - 2399-8083 .- 2399-8091 .- 0265-8135 .- 1472-3417. ; 41, s. 69-92 Tidskriftsartikel (refereegranskat)abstract The combination of growing mobility needs and dwindling transportation budgets in the Dutch Delta Metropolis has raised the need for smarter use of existing public transport infrastructure. A significant portion of this smarter use may come from strengthening the ties between infrastructure improvements and transit-oriented development. To further this goal, the Delta Metropolis Association has developed SprintCity (SprintStad in Dutch), a serious game and planning support tool that engages stakeholders in transit-oriented development to explore interaction between transport and land use, as described in Bertolini’s node–place model. However, its underlying database has proven insufficient to draw conclusions regarding urban character and development capacity around stations. This paper focuses on morphological research that aims to improve this database by exploring the density and urban morphology of station areas in the Delta Metropolis beyond readily available statistics, and discusses the methodological and theoretical underpinnings of this survey. The surveying of station areas in 2010 was conducted by a team of six researchers, based on the Spacemate© methodology developed by Berghauser Pont and Haupt. The methodology allows detailed quantitative measurement of the density and spatial characteristics of clearly demarcated urban districts, defining their so-called ‘spatial fingerprint’. The resulting database of 850 districts in 55 station areas has served descriptive goals, strengthening the realism in the SprintCity game, and serves as the database for further establishing the development potential of station areas.
12.	Forsemalm, Joakim, 1973, et al. (författare) Urban Qualities: ett kunskapsområde 2013 Rapport (övrigt vetenskapligt/konstnärligt)abstract Den här kunskapsöversikten är ett försök att utkristallisera relevant forskning såväl som praktisk kunskap för Mistra Urban Futures om urbana kvaliteter. Översikten är kopplad till ett arbete som genomförts under vår och höst 2011 med syfte att skapa underlag för den Strategiska plan som utgör grunden för Mistra Urban Futures planering och aktiviteter. Under våren 2011 arbetade sex grupper med varsitt kunskapsfält – urbana kvaliteter, urban förändring (”transitions”), urbana kulturer, urbana rättigheter, urban tillgänglighet och urban uthållighet. Tanken var att dessa skulle utgöra de sex bärande fokusområdena för centrets verksamhet. Sedermera kom dessa sex områden att slås ihop till tre - FAIR, GREEN och DENSE – vilka nu utgör de tre övergripande problem- och kunskapsområdena för Mistra Urban Futures.
13.	Dashti, Fatemeh, 1991 (författare) A ground-borne noise prediction model for railway traffic in tunnels in bedrock 2023 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Human life has become more manageable by the expansion of railway lines. However, despite providing convenience, railways increase noise and vibration in residential areas. Vibrations and noise generated by railways may harm human health, cause cosmetic damage and have an adverse impact on the environment. In order to reduce the effects of train-induced noise and vibration, efficient and accurate models for the prediction of ground-borne noise and vibration are required. Various analytical, theoretical, and experimental models have been developed to predict ground-borne noise. There is generally a lack of published information about parameters for ground-borne noise prediction concerning Swedish conditions with bedrock of high quality. Some investigations are reported, and a few consultancy companies have their own developed models, which are generally not publicly available. In fact, overall, the input data used to form these models and the methods of validation are not publicly available. Moreover, the statistical nature of the source and transfer paths requires that uncertainties are accurately handled in the model. This work aims to develop a model for ground-borne noise prediction for underground tunnels, to be used in Swedish Transport Administration projects. The methodology is formulated for three different stages based on precision and available information: location stage, planning stage, and construction stage. The first two stages correspond to planning and designing a railway track. The third stage involves the construction stage where more detailed information may be acquired. The prediction model presented here is developed for Swedish bedrock up to 1 kHz and formulated as a source term and several correction terms. These terms take into account various aspects, including train speed, distance attenuation, ground-to-building coupling, vibration levels on different floors and walls, how the room properties affect sound pressure levels within rooms, and different track treatments. Moreover, uncertainties are estimated using the standard deviation of each term. The required data are gathered from measurements in the Gårda tunnel in Gothenburg combined with existing data from measurements in the Åsa tunnel close to Varberg. As a result, a comprehensive model is suggested for ground-borne noise prediction in Swedish Transport Administration projects. However, the model is still under development, will be sent upon referral, and may undergo improvements.
14.	Altintas, Atilla, 1979, et al. (författare) EMD-SVR: A Hybrid Machine Learning Method to Improve the Forecasting Accuracy of Highway Tollgates Traveling Time to Improve the Road Safety 2021 Ingår i: Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering. - Cham : Springer International Publishing. - 1867-8211 .- 1867-822X. ; 364 LNICST, s. 241-251 Konferensbidrag (refereegranskat)abstract Tollgates are known as the bottleneck of the highways, which cause long waiting queues in rush-hour times of the day. This brings many undesirable consequences such as higher carbon emission and road safety issues. To avoid this scenario, traffic control authorities need accurate travel time forecasts at tollgates to take effective action to monitor potential traffic load and improve traffic safety. Accurate forecasting of the traffic travel time will help traffic regulators to prevent arising problems by taking action. The main objective of this study is to improve the short-term forecasting (minutes) of the traffic flow on highway tollgates by improving a novel hybrid forecasting method that combines Empirical Mode Decomposition with Support Vector Regression (EMD-SVR). Results claim that compared with SVR, the new proposed hybrid prediction model, EMD-SVR, can effectively improve prediction accuracy. Better forecasting of the traffic load will provide safer roads but will also lower the carbon emissions caused by longer traveling times.
15.	Andersson, Petra, et al. (författare) Safe introduction of battery propulsion at sea 2017 Rapport (övrigt vetenskapligt/konstnärligt)abstract Electric propulsion using batteries as energy storage has the potential to significantly reduce emissions from shipping and thus the environmental impact. The battery type that is currently on the top of the agenda to be used for ship propulsion applications is Li-ion batteries. Li-ion batteries pose different safety issues than e.g. other propulsion technologies and other batteries such as lead-acid batteries. It is essential that the safety level on board, including fire safety, is maintained, when introducing electric propulsion with energy storage in batteries. This report discusses the different regulations and guidelines available today for fire safety of batteries on board in relation to current knowledge about Li-ion batteries. Also fire safety measures available on board ships today and their applicability for Li-ion batteries is discussed, as well as the different test methods available and their applicability. A workshop gathering different stakeholders from Sweden, Norway and Finland identified fire safety as the main challenge for the introduction of battery propulsion at sea. The workshop concluded that future work is desired in order to increase knowledge and to develop publicly available strategies, training and designs.
16.	Basso, Rafael, 1979, et al. (författare) Electric Vehicle Routing Problem with Machine Learning for Energy Prediction 2021 Ingår i: Transportation Research Part B: Methodological. - : Elsevier BV. - 0191-2615. ; 145, s. 24-55 Tidskriftsartikel (refereegranskat)abstract Routing electric commercial vehicles requires taking into account their limited driving range, which is affected by several uncertain factors such as traffic conditions. This paper presents the time-dependent Electric Vehicle Routing Problem with Chance- Constraints (EVRP-CC) and partial recharging. The routing method is divided into two stages, where the first finds the best paths and the second optimizes the routes. A probabilistic Bayesian machine learning approach is proposed for predicting the expected energy consumption and variance for the road links, paths and routes. Hence it is possible to consider the uncertainty in energy demand by planning charging within a confidence interval. The energy estimation is validated with data from electric buses driving a public transport route in Gothenburg-Sweden as well as with realistic simulations for 24 hours traffic in the city of Luxembourg connected to a high fidelity vehicle model. Routing solutions are compared with a deterministic formulation of the problem similar to the ones found in the literature. The results indicate high accuracy for the energy prediction as well as energy savings and more reliability for the routes.
17.	Berghauser Pont, Meta, 1972, et al. (författare) INTEGRATED URBAN ENVIRONMENT EFFECT ANALYSIS OF INFRASTRUCTURAL TRANSFORMATIONS 2022 Rapport (övrigt vetenskapligt/konstnärligt)abstract The report presents the method developed within the research project ‘Stadsmiljöanalys- Analys av tätbebyggda miljöer i infrastrukturprojekt’, funded by Trafikverket (Swedish Transport Authority). This project sets up an integrated methodology for analysing and estimating the local impact of road and rail infrastructure projects in urban environments, either by way of new infrastructure or by way of retrofits, focusing on socioeconomic, environmental, and cultural-historical effects. While the focus is on national transport infrastructure investments, the method addresses local effects. This stems from the acknowledgement that each infrastructure investments results in a redistribution of accessibility where increasing accessibility on a regional and interurban scale might create encroachments on a local scale including the reduction of the usability of areas near to the infrastructure due to emissions and noise, risk of accidents, negative impacts on wildlife as well as barrier effects. It is these encroachments this method aims to highlight with the aim to reduce negative trade-offs of new or transformed transport infrastructure and recognize both local opportunities and sensitivities. In this project the direct effects of infrastructure projects in relation to the three perspectives (socioeconomic, environmental, and cultural-historical are described and measured in a precise manner through a series of spatial analyses. The cumulative, indirect, effects and broader consequences are also assessed, in relation to the sustainable development goals. The overall assessment methodology is based on a before-and-after analysis workflow, systematically comparing the existing situation (how it is, how it functions, how it affects people) to the future scenarios proposed by planning. The methodology is showcased using two infrastructural transformations projects in Söderköping and Mölndal, Sweden, as case studies. The overarching goal of the research project is to contribute to an improved integration between infrastructure and local urban areas and communities in projects initiated and developed by the Swedish Transport Authority, Trafikverket. The presented methodology builds on the ILKA (Integrerad landskapskaraktärsanalys) method, currently used by the Swedish Transport Authority. While ILKA focuses mainly on the inventory of the current landscape on a regional scale, this project widens the scope to also address urban areas and to include, besides the ecological descriptions, also socio-economic and cultural-historical analysis that are currently less emphasized. Such an integrated method can improve the ability of the Swedish Transport Authority to develop projects that contribute to sustainable urban development and, furthermore, create a unified work procedure in the organization.
18.	Bi, Hui, et al. (författare) Bicycle safety outside the crosswalks: Investigating cyclists' risky street-crossing behavior and its relationship with built environment 2023 Ingår i: Journal of Transport Geography. - : Elsevier BV. - 0966-6923. ; 108 Tidskriftsartikel (refereegranskat)abstract Most bicycle accidents are inextricably bound up with risky riding behaviors, which crossing the street illegally at unprotected mid-block locations is nothing to sneeze at. Compared with cyclists crossing the street at the crosswalk or intersections, there is a huge risk of accidents when they ignore or disobey road rules and across recklessly. Yet, the misbehavior of cyclists is an under-explored area in cyclist research due to the limited availability of detailed cycling data. This study creatively develops a GPS-based detection framework to capture risky street-crossing actions for the cyclists from large-scale bike sharing trajectory data. A data-driven modeling approach, based on structural topic modeling (STM), is developed to reveal the complexity and regularity of cyclists' habitual risky crossing behavior. Since objective built environment is one of the key factors associated with cycling, another goal of this paper is to apply a gradient boosting decision tree (GBDT) model to disentangle how the features of built environment may influence the frequency of risky crossing events. The case study results show that risky street-crossing behavior is prevalent in bicycle traffic – for example, 16.94% of cycling trips are involved in illegal crossing action. Most cyclists engage in illegal crossing behavior at the approximate central part of the streets and during the day, which reveals the presence of heterogeneity over space and time. Strong correlations between commuting activities and risky street-crossing behaviors are identified from topic modeling. Meanwhile, the latent illegal crossing patterns unraveled here highlight that typical reasons for committing the risky riding action include the lure of the travel destination across the road and the inconvenience of riding round in distant legal crossing facilities. GBDT findings provide new insights on the existence of the association between built environment and cyclists' illegal crossing action. The places related employment and catering play a dominant role in contributing risky street-crossing behavior, and the influences of road length, road level, bus stop and metro station are not neglectable. Most built environment attributes show nonlinear correlations with crossing frequency. It is anticipated that this study would successfully shed a first light on the pattern of cyclists' risky street-crossing behavior at the metropolitan scale, and compliment engineering practices to improve crossing behaviors and bicycle safety.
19.	Cao, Danni, et al. (författare) Quantification of the impact of traffic incidents on speed reduction: A causal inference based approach 2021 Ingår i: Accident Analysis and Prevention. - : Elsevier BV. - 0001-4575. ; 157 Tidskriftsartikel (refereegranskat)abstract This paper designs a systemic framework to quantify speed reduction induced by traffic incidents using a causal inference framework. The results can provide a reference to traffic managers for evaluating incident severities, thus take proper control measures after the incident in order not to underestimate or overestimate the negative impact. A two-phase scheme is proposed, including impacted region determination and speed reduction quantification. We first propose a Frame Region (FR) method, based on the shockwave propagation, to determine the spatiotemporal impacted region (SIR) using speed map. It is worth-noting that we design a statistical experiment to prove the rationality of congestion threshold selection. Secondly, we introduce a causal inference method for identifying the matched freeway segments. The traffic condition of finally matched freeway segments can be served as non-incident traffic condition of the incident occurred location, which contributes to quantifying the incident impact on speed reduction. We further demonstrate the proposed method in a case study by taking advantage of an incident record and related real freeway speed data in China. An interesting observation is that, along with the freeway segments away from the incident location, the congestion duration time of different freeway segments firstly rises and then decreases. The case study also illustrates the impact of incident on speed lasts almost 3 h and the congestion caused by the incident spreads 11 km, while the average causal effect of incident on all the impacted freeway segments is 42.3 km/h.
20.	Castrellon, Juan Pablo, 1989, et al. (författare) Enabling Factors and Durations Data Analytics for Dynamic Freight Parking Limits 2023 Ingår i: Transportation Research Record. - : SAGE Publications. - 0361-1981 .- 2169-4052. ; 2677:2, s. 219-234 Tidskriftsartikel (refereegranskat)abstract Freight parking operations occur amid conflicting conditions of public space scarcity, competition with other users, and the inefficient management of loading zones (LZ) at cities’ curbside. The dynamic nature of freight operations, and the static LZ provision and regulation, accentuate these conflicting conditions at specific peak times. This generates supply–demand mismatches of parking infrastructure. These mismatches have motivated the development of Smart LZ that bring together technology, parking infrastructure, and data analytics to allocate space and define dynamic duration limits based on users’ needs. Although the dynamic duration limits unlock the possibility of a responsive LZ management, there is a narrow understanding of factors and analytical tools that support their definition. Therefore, the aim of this paper is twofold. Firstly, to identify factors for enabling dynamic parking durations policies. Secondly, to assess data analytics tools that estimate freight parking durations and LZ occupation levels based on operational and locational features. Semi-structured interviews and focus group analyses showed that public space use assessment, parking demand estimation, enforcement capabilities, and data sharing strategies are the most relevant factors when defining dynamic parking limits. This paper used quantitative models to assess different analytical tools that study LZ occupation and parking durations using tracked freight parking data from the City of Vic (Spain). CatBoost outperformed other machine learning (ML) algorithms and queuing models in estimating LZ occupation and parking durations. This paper contributes to the freight parking field by understanding how data analytics support dynamic parking limits definition, enabling responsive curbside management.
21.	Garmabaki, A.H.S., et al. (författare) Assessing climate-induced risks to urban railway infrastructure 2024 Ingår i: International Journal of Systems Assurance Engineering and Management. - : Springer. - 0975-6809 .- 0976-4348. Tidskriftsartikel (refereegranskat)abstract Climate change and its severe impacts pose a number of challenges to transport infrastructure, particularly railway infrastructure, requiring immediate action. A railway system is a linear distributed asset passing different geographical locations and exposed to heterogeneous vulnerabilities under diverse environmental conditions. Furthermore, most of the railway infrastructure assets were designed and built without in-depth analysis of future climate impacts. This paper considers the effects of extreme temperatures on urban railway infrastructure assets, including rail, “switches and crossings”. The data for this study were gathered by exploring various railway infrastructure and meteorological databases over 19 years. In addition, a comprehensive nationwide questionnaire survey of Swedish railway infrastructure, railway maintenance companies, and municipalities has been conducted to assess the risks posed by climate change. A risk and vulnerability assessment framework for railway infrastructure assets is developed. The study shows that track buckling and vegetation fires due to the effect of hot temperatures and rail defects and breakage due to the effect of cold temperatures pose a medium risk. On the other hand, supportability losses due to cold temperatures are classified as high risk. The impact analysis helps infrastructure managers systematically identify and prioritize climate risks and develop appropriate climate adaptation measures and actions to cope with future climate change impacts.
22.	Hörteborn, Axel, 1986 (författare) Ship Behaviour and Ship Bridge Allision Analysis 2021 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract The demand for maritime transport has increased with the growing demand for worldwide trade. This has led to a major increase in maritime traffic and ship sizes over the last decades, which raises the probability of accidents. The methods used in maritime risk assessments today are based on old hypotheses that do not include all data available today. The main objective of this thesis is to develop numerical models and methods for the analysis of what is considered as normal navigation behaviour at sea today and improve the analysis of probability for ship-bridge allisions. The first part of the thesis describes what is considered as normal meeting distance at sea today. This information is later used while identifying failure events to ensure that the event behaviour was not caused by other ships. These few cases are excluded from the methodology since the communication and situational awareness in the situations are not known. However, while studying the probability of ship-bridge accidents, it is also important to understand how waterway restrictions may affect the probability of ship-ship collisions. Therefore, this thesis also includes a study of how the improved knowledge concerning meeting distance could be used in a near ship-ship collision identification model. One of the main findings considering normal meeting distance is that small and large ships meet each other at a similar distance at sea. In the second part of the thesis, a methodology is proposed to estimate the probability of ship-bridge allision. The presented methodology uses Automatic Identification System (AIS) data and a ship manoeuvring simulator to simulate and analyse marine traffic with regards to risks for accidents, such as ship-bridge allisions. A failure event identification method is also presented, which is needed to determine the frequency, duration and behaviour for the accident scenarios. The three events that were modelled and simulated in the simulator were: drifting ship, sharp turning ship and missing turning point. The probability of the different failure events corresponded to previous statistics confirming the AIS-based methodology. This means the methods to obtain the probability and duration of the failure events could be utilised in other areas. The simulation methodology was confirmed with the probability of grounding in the Great Belt VTS area. This thesis firstly contributes to a better understanding of the modelling of probability for ship-bridge allisions. This will support bridge-building engineers who need to take into account accidental loads from ship-bridge allision while designing bridges. Secondly, this thesis also contributes to a better representation of normal behaviour at sea, which is used both in fairway designs and in estimations of ship-ship collisions.
23.	Janné, Mats, 1979-, et al. (författare) Smart Construction Logistics Governance : A systems view of construction logistics in urban development 2021 Ingår i: Proceedings of the 57th ISOCARP World Planning Congress. - 9789075524697 Konferensbidrag (refereegranskat)abstract To reduce disturbances and impact from construction transports during urban development, logistics flows need to be managed and controlled efficiently. One way to do so is using construction logistics setups. However, these rarely take both initiator and end-user perspectives into consideration. The paper builds on a longitudinal multiple-case study with cases from Belgium, Norway, and Sweden. The cases provide insights on different tools and approaches for gathering stakeholder input, simulation and forecasting of transport volumes, what type of services are needed in urban construction projects, and different governance measures and incentives. A cross-case analysis was performed to find similarities and differences between the countries. The result of the study is a conceptual framework, presenting a systems overview of the decision routes in urban development linked to construction logistics.
24.	Karlsson, Tobias, 1984, et al. (författare) Tools to prevent waste in material flow in housing projects 2014 Ingår i: Proceedings of the 17th International Symposium on Advancement of Construction Management and Real Estate (CRIOCM 2012). - Berlin, Heidelberg : Springer Berlin Heidelberg. ; , s. 757-768 Konferensbidrag (refereegranskat)abstract There is a lack of apartments in major Scandinavian cities. At the same time, there is a general opinion in media that the costs for housing production are too high. Studies indicate that waste, in the lean perspective, is in the range of 30-35% of the project cost, excluding costs for land. Among initiatives for reducing waste are tools to prevent waste in material flows. This paper presents a case study in which a logistics company, a medium-sized contractor and a material supplier collaborated to develop tools for improving the material flow on the construction site. Initially, nine tools used for preventing waste in material flow is presented; logistic analysis, demand profile, process map, specifications for building hoist, delivery plan, responsibility during material handling, location in apartments, quantification of materials and control of deliveries. Then, each tool is evaluated concerning what kind of waste is reduced. Examples from a residential building project with 163 apartments are given. The costs associated with enhanced material logistics in this specific project were approximately SEK 130 per m2, which is equal to RMB 115 per m2. This covers the enhanced handling of 80% of the materials. It’s expected within the case project that enhanced logistics with support by the nine tools has a potential of giving a 2-5 times return on the investment. The conclusion is that material logistics requires good planning and structure in order to be effective and succeed in minimizing waste.
25.	Khosravi, Mahdi, 1988-, et al. (författare) Assessment of Railway Track Preventive and Corrective Tamping Recovery 2023 Konferensbidrag (refereegranskat)abstract Railway track, as a critical infrastructure, plays a significant role in freight transportation. However, Railway track degrades with age and usage and can impact negatively track availability and safety. Tamping actions are used to rejuvenate the degradation and recover the functionality of the track to an acceptable level. Tamping actions are performed in a form of preventive and corrective regimes. In performing an effective tamping regime, the recovery of both preventive and corrective tamping should be taken into account. In addition, the occurrence of isolated defects should be considered. By combining the recovery model with the degradation model, the long-term behavior of the track geometry can be predicted, and an accurate estimation of tamping needs can be provided, leading to optimum tamping scheduling. In this study, the effects of tamping recovery are modeled for both preventive and corrective strategies. For this aim, the values of both standard deviation (SD) and isolated defects have been predicted and their values before tamping are used as explanatory variables in a multivariable regression model. Finally, the effect of tamping recovery on the values of both SD and isolated defects is estimated. A case study is performed on a heavy haul line located in Sweden’s rail network to evaluate the performance of the proposed multivariable regression model. Observations showed that the model and its coefficients are significant with P-values close to zero, and the R-squared value suggests that the model explains approximately 70% of the variability in the response variable recovery.
26.	Li, Ying Zhen, et al. (författare) New models for calculating maximum gas temperatures in large tunnel fires 2016 Rapport (övrigt vetenskapligt/konstnärligt)abstract The work presented in this report focuses on estimating maximum gas temperatures at ceiling level during large tunnel fires. Gas temperature is an important parameter to consider when designing the fire resistance of a tunnel structure. Earlier work by the authors has established correlations between excess ceiling gas temperature and effective tunnel height, ventilation rate, and heat release rate. The maximum possible excess gas temperature was set as 1350°C, independent of the tunnel structure and local combustion conditions. As a result of this research, two models have been developed to better estimate possible excess maximum gas temperatures for large tunnel fires in tunnels with differing lining materials and structure types (e.g. rock, concrete). These have been validated using both model- and full-scale tests. Comparisons of predicted and measured temperatures show that both models correlate well with the test data. However, Model I is better and more optimal, due to the fact that it is more conservative and easier to use. The fire duration and flame volume are found to be related to gas temperature development. In reality, the models could also be used to estimate temperatures in a fully developed compartment fire.
27.	Lu, Yichen, et al. (författare) Analytical Method of Traffic Conflict at Urban Road Intersections Based on Risk Region 2021 Ingår i: Tongji Daxue Xuebao/Journal of Tongji University. - 0253-374X. ; 49:7, s. 941-948 Tidskriftsartikel (refereegranskat)abstract A two-stage method of traffic conflict analysis was proposed based on risk region. By using the inD dataset, traffic conflicts were recognized with the calculation of time to risk region(tTTR), and then the degree of traffic conflict risk was judged by risk region duration. Compared with the method based on time-to-collision(tTTC), the proposed method can not only identify rear-end conflicts and crossing conflicts more effectively, but also characterize the degree of traffic conflict risk at different times.
28.	Merisalu, Johanna, 1990, et al. (författare) A Framework for Risk-Based Cost-Benefit Analysis for Decision Support on Hydrogeological Risks in Underground Construction 2021 Ingår i: Geosciences (Switzerland). - : MDPI AG. - 2076-3263. ; 11:2, s. 1-19 Tidskriftsartikel (refereegranskat)abstract Construction below the ground surface and underneath the groundwater table is often associated with groundwater leakage and drawdowns in the surroundings which subsequently can result in a wide variety of risks. To avoid groundwater drawdown-associated damages, risk-reducing measures must often be implemented. Due to the hydrogeological system's inherent variability and our incomplete knowledge of its conditions, the effects of risk-reducing measures cannot be fully known in advance and decisions must inevitably be made under uncertainty. When implementing risk-reducing measures there is always a trade-off between the measures' benefits (reduced risk) and investment costs which needs to be balanced. In this paper, we present a framework for decision support on measures to mitigate hydrogeological risks in underground construction. The framework is developed in accordance with the guidelines from the International Standardization Organization (ISO) and comprises a full risk-management framework with focus on risk analysis and risk evaluation. Cost-benefit analysis (CBA) facilitates monetization of consequences and economic evaluation of risk mitigation. The framework includes probabilistic risk estimation of the entire cause-effect chain from groundwater leakage to the consequences of damage where expert elicitation is combined with data-driven and process-based methods, allowing for continuous updating when new knowledge is obtained.
29.	Mourad, Khaldoon, et al. (författare) Assessing flooding and possible adaptation measures using remote sensing data and hydrological modeling in Sweden 2022 Ingår i: Climate Risk Management. - : Elsevier BV. - 2212-0963. ; 38 Tidskriftsartikel (refereegranskat)abstract Recently, Europe is experiencing more frequent and greater floods compared to the last 500 years due to climate change among other factors. This has increased the associated risks, especially in urban areas, which poses a great challenge to all stakeholders. To protect traffic networks from possible floods, this paper uses QGIS, remote sensing data, and HEC-HMS model to assess flooding events and possible adaptation measures. Two case studies have been taken; 1) a 60-mm rainstorm that occurred in 2012 on a main road in the Northern part of Sweden (NB)); and 2) a 35-mm rainstorm that occurred in 2019 in the Southern part of Gothenburg (GO). The resulting flood hydrographs show that the peak reached are 0.5 m3/s and 3.8 m3/s in GO and NB, respectively. To adapt to these flood events, four adaptation measures were assessed namely afforestation, permeable pavements & green roofs, multi-use detention basins and culvert installation considering food production, biodiversity, prosperity, and the environment. The study has shown that afforestation is an effective flood risk mitigation measure to handle both moderate and extreme rain events. Well-maintained permeable surfaces and green roofs are effective in reducing flooding due to moderate rainfall, but not in reducing the impacts of extreme rainfall events. Well-designed multi-functional detention basins are good flood protection measures, however, if they are not well-maintained, their efficiency may be reduced by up to 90 %. Culverts are effective for frequent and limited rain events but extreme rain events may even increase flood risk and thereby contribute to damaging the infrastructure.
30.	Ouyang, Pengying, et al. (författare) Traffic safety analysis of inter-tunnel weaving section with conflict prediction models 2022 Ingår i: Journal of Transportation Safety and Security. - : Informa UK Limited. - 1943-9962 .- 1943-9970. ; 14:4, s. 630-654 Tidskriftsartikel (refereegranskat)abstract With increasing traffic demand in urban areas of metropolises, many tunnels have been constructed to improve road capacity and traffic mobility. The distance between two consecutive tunnels is relatively short which usually forms a weaving section, leading to considerable traffic conflicts. The objective of this study is to evaluate the safety performance of such inter-tunnel sections. Conflict prediction models based on negative binomial regression were developed to identify influential factors. Field data were collected at ten selected sites in Nanjing, China, and used for calibrating and validating the proposed models. Two types of inter-tunnel weaving sections (type 1 and type 2) were found in the field with distinct lane markings and operation rules. The unique lane markings in type 1 weaving sections are designed to isolate weaving traffic flows and thus reduce conflicts, but in practice, contradictory to its design intention, lead to more traffic conflicts compared with type 2 weaving sections. In addition, the length of the diverging section, merging section, and whole weaving section are found to be significant influencing factors on the conflict occurrence. The findings in the present study are expected to help engineers better design inter-tunnel sections.
31.	Ronchi, Enrico, et al. (författare) A risk analysis methodology for the use of crowd models during the Covid-19 pandemic 2020 Rapport (övrigt vetenskapligt/konstnärligt)abstract Pandemics such as Covid-19 have posed a set of questions concerning safe space usage given the risk of virus transmission in confined and open spaces. In this context, this report presents a risk analysis methodology for the use of crowd modelling tools as an aid to assess safety in confined and open spaces. Crowd models can be used to investigate people movement in the built environment, thus they have a great potential for the performance of proximity analysis. The report presented here addresses first the psychological and physical aspects linked to physical distancing (also called social distancing). Given the limited current knowledge on human behaviour and space usage during pandemics, the changes needed in crowd modelling tools to appropriately represent people movement are listed. This includes issues associated with modifications of the fundamental relationships between the key people movement variables (speed/flow vs density), and issues linked with interactions between pedestrians (e.g. collision avoidance, queuing mechanisms, route choice). Suggestions for new crowd modelling outputs are provided in order to enhance their use during pandemics. In addition, practical solutions concerning space usage are presented in light of the assessment of human safety through a risk evaluation based on proximity analysis and/or exposure assessment. This is deemed to help identifying design and management solutions to decrease the risk of virus transmission.
32.	Sundell, Jonas, 1984 (författare) Risk Assessment of Groundwater Drawdown in Subsidence Sensitive Areas 2018 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Groundwater leakage into sub-surface constructions can result in drawdown, subsidence in compressible materials, and costly damage to buildings and installations. When planning for sub-surface constructions where there is a risk for land subsidence due to groundwater drawdown, the need for safety measures must be carefully evaluated and managed. Since the sub-surface consists of heterogeneous and anisotropic materials, which cannot be fully investigated in all aspects, decisions regarding safety measures must be taken under uncertainty. In this thesis, a generic framework is presented on how to assess the risk of groundwater drawdown-induced subsidence (Paper I). As specific tools for modelling uncertainties in the groundwater drawdown – subsidence – damage chain, a method for probabilistic modelling of bedrock levels and soil stratification (Paper II) and a method for probabilistic modelling of ground subsidence to a large spatial extent (Paper III) are presented. These are combined with a probabilistic groundwater model and cost functions to calculate the economic risks of subsidence damage between different design alternatives (Paper IV). Finally, a novel method for economic valuation of hydrogeological information is presented in Paper V. The methods presented can distinguish between low and high-risk areas, identify the alternative with the highest net benefit compared to a reference alternative, and estimate the expected benefit of additional information. The methods have been demonstrated to provide useful support for decision-making and communication tools when assessing the risk of large-scale groundwater drawdown-induced subsidence in different infrastructure projects in Sweden.
33.	Toytziaridis, Angelos, 1991, et al. (författare) A Data-driven Markovian Framework for Multi-agent Pedestrian Collision Risk Prediction 2019 Ingår i: 2019 IEEE Intelligent Transportation Systems Conference, ITSC 2019. ; , s. 777-782 Konferensbidrag (refereegranskat)abstract Efficient travel with an Autonomus Vehicle (AV) through urban traffic scenes requires the AV to plan its path as a function of the risk of collision with nearby road users. We propose a framework based on Markov Chains to model the joint behavior of multiple road users, learn their joint behavior from previously observed behaviours, and predict the collision risk based on the learnt model. Using our framework we formulate two models which are based on position only and both position and velocity, respectively. The learning relies on real measurements of pedestrians at a crosswalk. Comparing the models on prediction horizons up to 6 s, we find that including velocity significantly changes the collision risk and that the model better predicts the pedestrian's future position. © 2019 IEEE.
34.	Wu, Jiaming, 1989, et al. (författare) Emergency vehicle lane pre-clearing: From microscopic cooperation to routing decision making 2020 Ingår i: Transportation Research Part B: Methodological. - : Elsevier BV. - 0191-2615. ; 141, s. 223-239 Tidskriftsartikel (refereegranskat)abstract Emergency vehicles (EVs) play a crucial role in providing timely help for the general public in saving lives and avoiding property loss. However, very few efforts have been made for EV prioritization on normal road segments, such as the road section between intersections or highways between ramps. In this paper, we propose an EV lane pre-clearing strategy to prioritize EVs on such roads through cooperative driving with surrounding connected vehicles (CVs). The cooperative driving problem is formulated as a mixed-integer nonlinear programming (MINP) problem aiming at (i) guaranteeing the desired speed of EVs, and (ii) minimizing the disturbances on CVs. To tackle this NP-hard MINP problem, we formulate the model in a bi-level optimization manner to address these two objectives, respectively. In the lower-level problem, CVs in front of the emergency vehicle will be divided into several blocks. For each block, we developed an EV sorting algorithm to design optimal merging trajectories for CVs. With resultant sorting trajectories, a constrained optimization problem is solved in the upper-level to determine the initiation time/distance to conduct the sorting trajectories. Case studies show that with the proposed algorithm, emergency vehicles are able to drive at a desired speed while minimizing disturbances on normal traffic flows. We further reveal a linear relationship between the optimal solution and road density, which could help to improve EV routing decision makings when high-resolution data is not available.
35.	Berghauser Pont, Meta, 1972, et al. (författare) Förtätning av stationsnära områden för god tillgänglighet. Utveckling av en analys - och utvärderingsmetod 2022 Rapport (övrigt vetenskapligt/konstnärligt)abstract Det finns en vilja att förtäta i närheten av stationer för att öka användningen av kollektivtrafik och därmed minska klimatpåverkan kopplad till transpor- ter. Förtätning bidrar bland annat till att skapa levande stationssamhällen, med blandade funktioner, god tillgäng- lighet och miljöer som är trygga och vistelsevänliga där olika grupper och behov möts. Potentialerna är många men så även utmaningarna. Förtätning av stationsnära områden kan också leda till oönskade konsekven- ser för social, ekonomisk och ekologisk hållbarhet. Den här rap- porten kan förhoppningsvis ge ökad förståelse för förtätning i relation till regional tillgänglighet samt för positiva och negativa konsekvenser av förtätning i stationsnära områden. Den kan också skapa insikter om hur olika alternativ för utveckling av stations- nära områden kan värderas utifrån Agenda 2030, särskilt Mål 11: Hållbara städer och samhällen. Rapporten är framtagen inom projektet Urbana stationssamhäll- en – förtätning av stationsnära områden för god tillgänglighet (2020–2022) som finansierats av Trafikverket och bedrivits i sam- verkan mellan Urban Futures vid GMV (projektägare), Arkitektur och samhällsbyggnadsteknik vid Chalmers tekniska högskola, Gö- teborgsregionen (GR), Samhällsplanering vid Högskolan Dalarna och Samhällsplanering och miljö vid KTH.
36.	Elldér, Erik (författare) Leder förtätning till ett minskat bilresande? 2018 Ingår i: Plan. - 0032-0560. ; 2018:2-3, s. 75-78 Tidskriftsartikel (refereegranskat)
37.	Stojanovski, Todor, 1976- (författare) Urbanism for Multimodal Transportation : Multimodal Transportation Performance Certificates (MTPC) for Buildings and Neighborhoods 2017 Rapport (övrigt vetenskapligt/konstnärligt)abstract Multimodality defines the ability to travel with a choice of different transportation modes. This report combines different approaches and methods to analyze multimodality and inform about integration of multiple transportation modes with cities. It assesses three methods: green building and sustainable neighborhood certification systems (LEED, Leadership in Energy and Environmental Design), accessibility indexes (Walk Score, http://www.walkscore.com/) and travel forecasting tools (Trafikverket’s Trafikalstring, Swedish Transportation Administration’s Trip Generation Tool, https://applikation.trafikverket.se/trafikalstring/). It also proposes instituting Multimodal Transportation Performance Certificates (MTPC) as a hybrid method. The focus is on urban form, physical integration of transportation systems in cities and on urbanism that can make multimodality possible. Accordingly, MTPC measures physical integration of different transportation systems (walking, cycling, public transportation and private car) with cities. Its indicators include design elements (streets, buildings, building façades, building heights, bike racks, parking lots, bus stops, subway exits, etc.), place characteristics (density, diversity, etc.) and accessibility (network access to local and regional destinations) that have indirect, but profound effect on travel.
38.	Thunberg, Micael, 1986-, et al. (författare) Bringing planning back into the picture : How can supply chain planning aid in dealing with supply chain related problems in construction? 2018 Ingår i: Construction Management and Economics. - : Routledge. - 0144-6193 .- 1466-433X. ; 36:8, s. 425-442 Tidskriftsartikel (refereegranskat)abstract There are several supply chain related problems facing the construction industry, such as poor construction site logistics, lack of communication and trust. These problems can jeopardise construction projects through delays and cost overruns. Supply chain planning, a part of supply chain management (SCM), can be used as a tool to deal with these problems. The purpose of this paper is to study how linkages between common supply chain related problems in construction can be illustrated and to demonstrate how they could be resolved through supply chain planning. Firstly, we identify how the linkages between common problems can be illustrated, and secondly the role of supply chain planning in resolving these problems. A conceptual model is developed that was verified using three cases with Swedish gypsum and kitchen supply chains. The model is shown to be useful in illustrating how supply chain problems occurring at executional level on-site are related to problems originating in lack of planning at company/pre-construction level. The study thus demonstrates how supply chain planning can aid in resolving supply chain problems. The paper contributes by bringing planning back into the picture and by showing how supply chain planning can help to adopt SCM in construction.
39.	Trosvik, Lina, 1991-, et al. (författare) A meta-evaluation of climate policy evaluations : findings from the freight transport sector 2023 Ingår i: Transport reviews. - : Routledge. - 0144-1647 .- 1464-5327. ; 43:5, s. 867-887 Tidskriftsartikel (refereegranskat)abstract Knowledge about how implemented policy instruments have performed is important for designing effective and efficient policy instruments that contribute to reductions of greenhouse gas emissions. This paper carries out a meta-evaluation of ex-post evaluations of climate policy instruments in the freight transport sector. By analysing the outcomes and quality of evaluations, the aim is to identify whether estimated effects of policy instruments can be compared between evaluations and if the results are appropriate to use for evidence-based decision making. To analyse these aspects, commonly applied evaluation criteria are assessed and classified according to an assessment scale. We confirm that few ex-post evaluations are carried out and that there is a gap between evaluation theory and how ex-post policy evaluations are performed in practice, where evaluation criteria recommended in policy evaluation guidelines are found to often be neglected in evaluations. The result is a lack of systematic climate policy evaluation which hinders reliable conclusions about the effect of policy instruments. There is a need for more systematic monitoring and evaluation of implemented policy instruments and we suggest that evidence-based decision making can be improved by adjusting current policy evaluation guidelines and by introducing an evaluation obligation.
40.	Trosvik, Lina, 1991, et al. (författare) A meta-evaluation of climate policy evaluations: findings from the freight transport sector 2023 Ingår i: Transport Reviews. - : Informa UK Limited. - 1464-5327 .- 0144-1647. ; 43:5, s. 867-887 Tidskriftsartikel (refereegranskat)abstract Knowledge about how implemented policy instruments have performed is important for designing effective and efficient policy instruments that contribute to reductions of greenhouse gas emissions. This paper carries out a meta-evaluation of ex-post evaluations of climate policy instruments in the freight transport sector. By analysing the outcomes and quality of evaluations, the aim is to identify whether estimated effects of policy instruments can be compared between evaluations and if the results are appropriate to use for evidence-based decision making. To analyse these aspects, commonly applied evaluation criteria are assessed and classified according to an assessment scale. We confirm that few ex-post evaluations are carried out and that there is a gap between evaluation theory and how ex-post policy evaluations are performed in practice, where evaluation criteria recommended in policy evaluation guidelines are found to often be neglected in evaluations. The result is a lack of systematic climate policy evaluation which hinders reliable conclusions about the effect of policy instruments. There is a need for more systematic monitoring and evaluation of implemented policy instruments and we suggest that evidence-based decision making can be improved by adjusting current policy evaluation guidelines and by introducing an evaluation obligation.
41.	Billberg, Ingmar, 1946-2005 (författare) Prestigefyllt broprojekt 1991 Ingår i: Kulturmiljövård. - Stockholm : Riksantikvarieämbetet. - 1100-4800. ; [16]:2, s. 55-56 Tidskriftsartikel (populärvet., debatt m.m.)
42.	Curtis, Carey, et al. (författare) Public Transport Accessibility Tools Matter: A case study of Gothenburg, Sweden 2019 Ingår i: Case Studies on Transport Policy. - : Elsevier BV. - 2213-624X. ; 7:1, s. 96-107 Tidskriftsartikel (refereegranskat)abstract Urban transport investment decision-making has relied on traditional modelling tools that forecast travel demand based on existing travel patterns. This approach has also underpinned decisions about future urban development. Latent travel demand is poorly understood, and this is particularly important given policy aspirations for the take-up of more sustainable transport modes such as public transport. Accessibility tools can make an important contribution to future development and investment decisions given this policy aspiration. In this paper, public transport supply is assessed using an accessibility tool and then compared to travel patterns. By assessing both public transport supply and travel demand through an accessibility lens we are able to gain insight into the latent demand for public transport. An innovative segmentation type approach is employed by comparing supply and demand and from this a typology is proposed as a framework for a more holistic public transport investment strategy. This takes into account public transport accessibility, travel demand of trip makers and their socio-economic situation, set in the context of the urban region.
43.	Ekeskär, Andreas, 1984-, et al. (författare) Third-party logistics in construction : the case of a large hospital project 2016 Ingår i: Construction Management and Economics. - : Routledge. - 0144-6193 .- 1466-433X. ; 34:3, s. 174-191 Tidskriftsartikel (refereegranskat)abstract The construction supply chain is of temporary nature and complex, with many interactions between multiple actors in different construction projects. This challenging context typically leads to relatively higher costs and lower productivity, compared to other industries. Supply chain management (SCM) has been put forward as a mean to better handle this challenging context. As a part of SCM initiatives some construction industry stakeholders have turned to third-party logistics (TPL) providers, especially in large construction projects. The use of TPL providers is a new, and under-investigated, phenomenon in the construction industry. The main purpose of this study is thus to explore the use of a TPL provider in a large construction project and to analyse its resulting effects. Driving forces and possible concerns for implementing TPL are identified and the possibility for TPL to be a facilitator for implementing SCM in construction is investigated. The research is based on a literature review and an explorative case study of a large hospital project in Sweden, where the client and the main contractor have initiated the use of a TPL provider to coordinate sourcing and materials handling activities on site. The results show positive effects on establishing an effective interface between the construction site and the supply chain. The results also show that a TPL solution facilitates an increase in productive work at the construction site itself, a reduction of costs and an increased utilisation of site assets. On the downside, the study also shows a lack of SCM knowledge amongst the involved actors in the project, hindering them to reap the full potential of TPL.
44.	Forssén, Jens, 1968, et al. (författare) Road traffic noise disease burden estimates for a model study of varying urban morphology cases 2021 Ingår i: Proceedings of INTER-NOISE 2021 - 2021 International Congress and Exposition of Noise Control Engineering. - : Institute of Noise Control Engineering (INCE). Konferensbidrag (refereegranskat)abstract In a model study containing 31 different building morphologies in an urban setting, road traffic noise exposure has been calculated and analysed. For five of the building morphologies also vegetation surfaces on facades and roofs were studied. The facade exposure levels were analysed for both smaller (single-sided) flats and larger (floor-through) flats, considering the direct exposure from the roads as well as the non-direct exposure at noise-shielded positions like inner yards, applying a noise mapping software in combination with a prediction model for the non-direct exposure. Using noise indicators Lden and Lnight, the disease burden, in terms of DALY (Disability-Adjusted Life Years) per person, was estimated and analysed, via predictions of annoyance and sleep disturbance. As general trends, perimeter blocks were shown to perform better than morphologies with less enclosed yards and densification was shown to result in improved performance, assuming a constant traffic flow. In addition, complementing the perimeter blocks with towers was shown to enable improvement. Furthermore, traffic concentration by locating all local traffic to a single road was shown to be beneficial, increasingly so by widening the road. The use of facade vegetation was shown to result in significant overall improvement.
45.	Fredriksson, Anna, et al. (författare) An Interactive Visualization Tool for Collaborative Construction Logistics Planning—Creating a Sustainable Project Vicinity 2022 Ingår i: Sustainability. - : MDPI. - 2071-1050. ; 14:24 Tidskriftsartikel (refereegranskat)abstract The intensity of urban development is presently high, creating a construction boom. The number of transports per project is a major consideration in urban goods transport and emissions from a project. Presently, the stakeholders take part in a “blame game” in assigning fault for the emissions from construction transport and the disturbances to society in the vicinity of construction sites. Incorporation of logistics into urban planning requires an increased understanding of the interaction between construction transport flows and urban land use, and the inclusion of different stakeholders. The purpose of the study is to support collaborative planning of construction transport in urban planning, and specifically to explore how a planning tool based on interactive visualization could be designed. An action research process has generated two prototypes of an interactive visualization tool for collaborative planning of construction transport. The prototype facilitates a “shared deliberation space” by identifying alternatives and assessing predicted consequences, which supports a collaborative urban planning process. Based on the research conducted, we claim that the responsibility of construction transport planning should be taken by the municipality, i.e., the urban planning and traffic planning functions. © 2022 by the authors.
46.	Frühwald, Eva, et al. (författare) Teachers’ view on combining assessment elements into a holistic assessment concept 2008 Ingår i: [Host publication title missing]. Konferensbidrag (refereegranskat)abstract Abstract in UndeterminedAssessments of students’ knowledge and skills are sometimes habitually performed, but the design of proper assessment concepts – beneficial to both teaching and learning – ought to be a central issue for all course planners in higher education. The main purpose of this paper is to discuss a variety of assessment elements, as well as ways in which to combine them. It uses experiences from Lund University’s Faculty of Engineering (LTH) to provide suggestions and advice for course planners. The discussion is based on the combination of a literature review in the field of teaching and learning, of empirical material obtained from surveys and group discussions with 22 teachers at LTH, and of the authors’ own experiences in their capacity as course leaders and teachers. The study reveals a preference for projects and written assessment, as compared with the less preferred individual oral assessment. The paper indicates potential for quality enhancements through the adapted tailoring of assessment elements into holistic assessment concepts.
47.	Gharaibeh, Lina, et al. (författare) An Empirical Analysis of Barriers to Building Information Modelling (BIM) Implementation in Wood Construction Projects: Evidence from the Swedish Context 2022 Ingår i: Buildings. - : MDPI AG. - 2075-5309. ; 12:8 Tidskriftsartikel (refereegranskat)abstract Building information modelling is gradually being recognised by the architecture, engineering, construction, and operation industry as a valuable opportunity to increase the efficiency of the built environment. Focusing on the wood construction industry, BIM is becoming a necessity; this is due to its high level of prefabrication and complex digital procedures using wood sawing machines and sophisticated cuttings. However, the full implementation of BIM is still far from reality. The main objective of this paper is to explore the barriers affecting BIM implementation in the Swedish construction industry. An extensive literature review was conducted to extract barriers hindering the implementation of BIM in the construction industry. Secondly, barriers to the implementation of BIM in the wood construction industry in Sweden were extracted using the grounded theory methodology to analyse expert input on the phenomenon of low BIM implementation in the wood construction industry in Sweden. Thirty-four barriers were identified. The analysis of this study also led to the development of a conceptual model that recommended solutions to overcome the barriers identified to help maximise BIM implementation within the wood construction industry. Identifying the main barriers affecting BIM implementation is essential to guide organisational decisions and drive policy, particularly for governments that are considering articulating regulations to expand BIM implementation.
48.	Gschösser, Florian, et al. (författare) Hidden Ecological Potentials in the Production of Materials for Swiss Road Pavements 2012 Ingår i: Journal of Management in Engineering - ASCE. - 0742-597X. ; 27:1, s. 13-21 Tidskriftsartikel (refereegranskat)abstract Sustainability has become a major concern in the field of civil infrastructures in recent years. Developing road construction projects with lower ecological impacts over a project’s entire life cycle can help in making road infrastructure contribute to sustainable development. This study focuses on the ecological potentials in the production of road materials used in Swiss road pavements. The environmental assessment was performed using a cradle-to-gate life-cycle assessment (LCA) approach in which all processes from the raw material extraction to the finished product were considered. The comparison of the results of the best-case asphalt pavement and the standard asphalt pavement for Swiss highway construction shows ecological potentials of up to 55%. Use of the best-case concrete pavement lowers the environmental impact by up to 53% in comparison to the worst-case concrete pavement for Swiss highways. Concerning composite pavements, the best-case variant offers an ecological potential 38% higher than the standard pavement.
49.	Li, Ying Zhen, et al. (författare) Analysis of Muskö tunnel fire flows with automatic sprinkler activation 2017 Rapport (övrigt vetenskapligt/konstnärligt)abstract The focus of the present study is analyzing the best position of a sprinkler nozzle in a tunnel cross-section in the Muskö tunnel, south of Stockholm, Sweden. Activation of the sprinklers installed along the centerline and along the sidewall is investigated through analysis of full scale experiments and by three dimensional numerical modelling. Then the tunnel velocity is analyzed by one dimensional numerical modelling for various fire locations in the Muskö tunnel. For both activating the automatic sprinklers nearby the fire and avoiding activation of the sprinklers further downstream, the automatic sprinklers are recommended to be installed along the centerline of the tunnel. It has also been found that the tunnel velocity varies significantly with the fire location. When the fire is on the left side of the tunnel, the flow velocity mostly remains in a range of 1 m/s (positive or negative) within the first 10 minutes, which helps early activation of the automatic sprinklers. When the fire is on the right side of the tunnel, the flow velocity mostly remains within a range of -1 m/s and 1 m/s within the first 5 minutes, and the velocity mostly increases to 2 m/s at around 10 min. Therefore, the scenario for fire located on the left side is better than that for fire on the right side, especially when it is located between the middle of the right section and the right portal. As one typical case with fire on the right side, the tunnel velocity maintains at 1 m/s for the first 5 min and gradually increases to 2 m/s at 10 min. Under such conditions, the automatic sprinkler system is expected to perform well.
50.	Li, Ying Zhen (författare) Study of fire and explosion hazards of alternative fuel vehicles in tunnels 2018 Rapport (övrigt vetenskapligt/konstnärligt)abstract An investigation of fire and explosion hazards of different types of alternativefuel vehicles in tunnels is presented. The different fuels are divided into four types:liquid fuels, liquefied fuels, compressed gases, and electricity, and detailed parameters are obtained. Three types offire hazards for the alternativefuel vehicles: pool fires, jet fires and fireballs are identified andinvestigated in detail. Fromthe perspective of pool fire size, the liquid fuels pose equivalent or evenmuch lower fire hazards compared to the traditionally used fuels, but theliquefied fuels may pose higher hazards. For pressurized tanks, the fires are generally much larger in size butshorter in duration. The gas releases from pressure relief devices and the resulting jet firesare highly transient. Forhydrogen vehicles, the fire sizes are significantly higher compared to CNGtanks, while flame lengths only slighter longer. Investigation of the peakoverpressure in case of an explosion in a tunnel was also carried out. Theresults showed that, for the vehicles investigated, the peak overpressure of tankrupture and BLEVE are mostly in a range of 0.1 to 0.36 bar at 50 m away. Thesituations in case of cloud explosion are mostly much more severe andintolerable. These hazards need to be carefully considered in both vehiclesafety design and tunnel fire safety design. Further researches on thesehazards are in urgent need.

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