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The main goal of this study is to increase the crashworthiness performance of tubular composite to absorb more energy by optimizing the orientation of its fibers. The crashworthiness performance of glass fiber-reinforced polymer (GFRP) composite pipes manufactured using the filament winding process is investigated in detail. The effects of fiber orientation and thickness of tube wall on energy absorption capabilities were investigated through quasi-static compression tests. The composite pipes were produced with 1200 tex E-glass fibers and Epikote 828 resin as the matrix material. The winding angles of ±30°, ±45°, ±55°, ±75°, and ±90° were examined, and the number of winding layers ranged from 1 to 3 were also examined. Quasi-static axial compressive loading was applied to 15 specimens using a hydraulic actuator. The results revealed that single-layered samples experienced buckling damage at low load levels, while an increase in the number of layers led to higher load-carrying capacity and different types of damage. Furthermore, as the number of layers increased, the load-carrying capacity and energy absorption capacity significantly improved. Progressive failure was observed in [±90°] wound samples for all layer configurations, with [±90°]3 exhibiting the highest performance in terms of load-carrying capacity and energy absorption. The damaged shapes indicated a combination of fiber separation, buckling, diagonal shearing failure, and crushing in the upper and lower heads.

Recent work has offered a more nuanced view of incumbent actors' roles in transitions, yet a comprehensive understanding of how reorientation activities and subsequent interaction patterns among different incumbent actor types shape the direction of system reconfigurations remains underexplored. This paper proposes a framework for empirically assessing actors' relational dynamics in response to low-carbon transitions and conceptualises actor interaction types and the nature of their interaction. Through a case study of the low-carbon transition of road freight transport in Sweden, we examine how reorientation dynamics, e.g., coalitions, competition, and contestations, can facilitate and hinder system reconfigurations by creating regime tensions. Our study highlights that incumbency reorientations are multi-dimensional, with actor involvement and strategies varying, leading to divergent actor positions and role constellations as actors attempt to reconfigure the focal regime. Extending beyond the Swedish case, five avenues for future research are outlined.

This open access book includes detail on various structures, buildings, and building materials from different structural and sustainability perspectives. It describes how the building industry is vital for the achievement of the sustainable development goals, namely, economic growth, social progress, and the effective protection of the environment. The aim of this collection is to foster the design and construction of sustainable structures and buildings to reduce the environmental load, connect with the environment, and benefit the health of occupants. Presenting the knowledge, trends, and developments from a group of contributors in the field working with different kinds of structures, structural components, buildings, and building materials, the book is ideal for practitioners working in commercial settings, as well as engineering students and researchers concerned with sustainability issues.

The purpose of this book is to expand the knowledge and skills of civil and structural engineers and researchers and help them better understand, design, and analyze civil engineering applications. This book examines advancements in structural integrity and failure and underground construction. It offers profound insights into the mechanisms that can lead to the integrity or failure of structures and result in safe underground construction. It provides details on the fundamental principles, theories, behavior, and performance of different structural elements and underground construction. The book delves into the mechanics, design, and construction of reinforced concrete structures. It explores the design principles applied to reinforced concrete structures and considers critical structural elements like beams, slabs, columns, and foundations. It also demonstrates various advances in reinforced concrete technology, including high-performance concrete, fiber-reinforced concrete, self-compacting concrete, and the use of nanomaterials. It describes methods for the analysis and evaluation of reinforced concrete structures, non-destructive testing methods, structural health monitoring, finite element analysis, and causes of failure. In addition, the book proposes a design model for determining the flexural bearing capacity of reinforced concrete beams having reinforcement steel with reduced modulus of elasticity. Moreover, the book investigates the effects of loading rates on the mechanical properties of structural steel. It also evaluates the formation of welding defects in the process of connecting steel structures, which is inevitable, from the aspect of failure mechanics. In addition, it utilizes an equivalent shell-wire model to propose a simple accurate technique for nonlinear assessment of reinforced concrete shear walls with less computational cost. The book introduces tunnel design theory and method, support structure systems, construction technology, and equipme

Construction projects, especially those for commercial purposes, require thorough planning and control to ensure success within predetermined budgets and timelines. This research, conducted in Mashhad, Iran, employs the analytic hierarchy process (AHP) and VIKOR methods to identify and rank factors influencing delays in high-rise projects. The study, based on a sample of 40 projects, emphasizes the comprehensive nature of our research method. The scale for features in project selection includes societal importance (with different applications including cultural hubs, affordable housing initiatives, and urban renewal for social equity), size (less and more than 20 units in residential projects), and diversity (mixed-use development, inclusive infrastructure, and cultural and recreational spaces), contributing to a comprehensive analysis of construction delays. Expert project managers and engineers provided insights through two questionnaires, and their responses underwent thorough analysis. Our findings not only underscore the significance of factors contributing to project success but also rank their impact on the likelihood of delays. The study reveals that the negative effects of these factors on cost, time, and project quality vary. Time emerges as the most influential parameter, with approximately six times more impact on cost and nine times more on quality. Contractor financial weakness, delays in allocating financial and credit resources, insufficient project resource allocation, contractor technical and executive weakness, and a lack of proper implementation and project control are identified as the most important factors contributing to delays.

Soil-working tools in agriculture are made of boron-containing steels with high wear resistance and hardenability. Nevertheless, these tools are subject to high impacts, abrasive wear, and fatigue and are therefore prone to failure. To combine varying levels of properties within one component in as-quenched condition can be beneficial for such products. To obtain this property variation, a component must undergo a complex and controllable cooling. Therefore, the aim of this work is to obtain a microstructure gradient along two 15 mm-thick steel plates in a newly developed test rig by water jet impingement technique to confirm its controllability and flexibility. Furthermore, a quenching simulation model is created for hardness prediction using phase transformation data from a machine learning tool. Microstructure variation is observed using light optical microscopy and the electron backscatter diffraction technique. Mechanical properties are studied through tensile tests and hardness measurements and are also compared with simulation results. The 0.27 mass% C steel sample is obtained in almost fully martensitic state transitioning to a softer ferritic/bainitic condition, while the 0.38 mass% C steel sample results predominantly into a fully hardened martensitic state and slightly shows ferritic and bainitic features along the sample. The quenching simulation model shows promising hardness prediction for both steels.

A novel generation of composite sandwich beams with laminated carbon fiber-reinforced polymer skins and pultruded glass fiber-reinforced polymer core materials was examined for their flexural behavior. The strength and failure mechanisms of the composite sandwich beams in flatwise and edgewise configurations were investigated using three-point static bending tests. These sophisticated composite structures must be designed and used in a variety of sectors, and our research provides vital insights into their performance and failure patterns. In comparison to the reference specimens (FGM-1), the carbon nanotube-reinforced specimens’ bending capacity was affected and ranged from −2.5% to 7.75%. The amount of the carbon nanotube addition had a substantial impact on the beams’ application level and load-carrying capacity. Particularly, the application of 0.5 wt% additive in the outermost fiber region of the beams, such as in FGM-4, led to an increase in the bending capacity. However, the stiffness values at the maximum load were decreased by 0.3%–18.6% compared to FGM-1, with the minimum level of the decrease in FGM-4. The experimental results were compared with the theoretical calculations based on the high-order shear deformation theory, which yielded an approximation between 11.99% and 12.98% by applying the Navier’s solution.

The use of timber as a building material is becoming increasingly popular thanks to its superior environmental performance compared with concrete and steel. However, timber structures rely on solid connections to improve their weak expansibility. Steel connections can be prone to corrosion over time, leading to the decreased structural integrity. Additionally, steel connections require more material and energy to manufacture and install compared with timber connections. This article focuses on the flexural performance of cross-laminated timber (CLT) panels with adhesive-free edge connections under four-point bending tests. First, numerical models of experimentally tested CLT panels were constructed using the finite element (FE) software ABAQUS. Then, these FE models were validated with the comparisons of their results with those of the experimental tests. Afterward, four new adhesive-free edge connections using timber for the CLT panels were developed in this study, helping sustainable construction. Utilizing the designed edge connections of the current study, forty-one parametric studies were numerically conducted on the connected CLT panels to investigate their ultimate loads, strains, displacements, moment capacities, failure modes, and effective stiffness. The factors affecting the edge connections’ load-bearing capacity were also examined and discussed. The study provides helpful insights into the development of CLT as a sustainable construction material with improved adhesive-free edge connections.

Cement-based composites, as primary construction materials, have undergone significant advancements over the years, yet researchers still face challenges in terms of their durability and impact on the environment. The goal of this research is to develop environmentally friendly cementitious composites blended with sugarcane bagasse ash (SCBA) and reinforce them with multi-walled carbon nanotubes and polypropylene (PP) fibers. Because of the high cost associated with carbon nanotubes (CNTs) and PP fibers, as well as CO2 emission, which affect the economic and environmental aspects of this field, an agricultural waste such as SCBA was introduced in the current study that is both economically and environmentally viable. For this purpose, five mixes were designed by varying the CNTs content whilst keeping the PP fibers and SCBA contents constant at 1.5% and 15% by weight of the binder (ordinary Portland cement + SCBA), respectively. The developed blends were tested for various mechanical and durability properties, i.e., compressive strength, flexural strength, impact strength, water absorption, and ultrasonic pulse velocity. Moreover, the microstructures of the newly developed low-carbon SCBA-based composites reinforced with PP fibers and CNTs were studied through scanning electron microscopy and energy dispersive spectroscopy. The results showed that the developed blends incorporating 15% SCBA, 1.5% PP fibers, and 0.08% CNTs, by weight of the binder, demonstrated the compressive, flexural, and impact strengths as 15.30 MPa, 0.98 MPa, and 0.11 MPa, respectively. The investigated blends proved to be cost-effective and environmentally beneficial, rendering them suitable for utilization in general construction and maintenance works.

In the pursuit of creating more sustainable and resilient structures, the exploration of construction materials and strengthening methodologies is imperative. Traditional methods of relying on steel for strengthening proved to be uneconomical and unsustainable, prompting the investigation of innovative composites. Fiber‐reinforced polymers (FRPs), known for their lightweight and high‐strength properties, gained prominence among structural engineers in the 1980s. This period saw the development of novel approaches, such as near‐surface mounted and externally bonded reinforcement, for strengthening of concrete structures using FRPs. In recent decades, additional methods, including surface curvilinearization and external prestressing, have been discovered, demonstrating significant additional benefits. While these techniques have shown the enhanced performance, their full potential remains untapped. This article presents a comprehensive review of current approaches employed in the fortification of reinforced cement concrete structures using FRPs. It concludes by identifying key areas that warrant in‐depth research to establish a sustainable methodology for structural strengthening, positioning FRPs as an effective replacement for conventional retrofitting materials. This review aims to contribute to the ongoing discourse on modern structural strengthening strategies, highlight the properties of FRPs, and propose avenues for future research in this dynamic field.

Structures known as modular buildings are made in factories and then moved to construction sites, where they are assembled. The efficacy of modular structures under many uncertainties has to be thoroughly investigated as demand rises; fire is one such uncertainty. The purpose of this study is to ascertain how high temperature affects the components of modular constructions. In the current study, hollow steel columns and beams were taken into account as components of a modular construction. Using ABAQUS, several situations were examined depending on the span length to determine the important locations of the members. Experimental research was conducted on the critical regions identified by the analysis, and the results were contrasted with those of the analysis. A high-temperature localized heating furnace was used for the experimental testing. The findings demonstrated that for spans of 250 mm and 500 mm, the central area of the beams was essential, and the load-carrying capacity was six times less than that of heating at the extremities of the beams. Similar to the beams, columns exhibited less fluctuation than the beams and were weaker in the bottom area when exposed to high temperature. When compared to other places, the capacity was reduced by 1.1 times, and in Case 1, the capacity reduction with regard to loading was 1.68 times greater.

Glass fiber-reinforced polymer (GFRP) reinforcements are superior to traditional steel bars in concrete structures, particularly in vertical elements like columns, and offer significant advantages over conventional steel bars when subjected to axial and eccentric loadings. However, there is limited experimental and numerical research on the behavior of GFRP-reinforced concrete (RC) columns under eccentric loading having different spacing of stirrups. In this study, six specimens were cast under three different values of eccentricities (25 mm, 50 mm, and 75 mm) with two groups of stirrups spacing (50 mm and 100 mm). The experimental results showed that by increasing the eccentricity value, there was a reduction in the load-carrying capacity of the specimens. The finite element ABAQUS software was used for the numerical investigation of this study. The results from the finite element analysis (FEA) were close to the experimental results and within the acceptable range. The maximum difference between the experimental and FEA results was 3.61% for the axial load and 12.06% for the deformation.

Nowadays, due to the structural advantages gained by combining three different materials’ properties, columns made of carbon-fiber reinforced polymer (CFRP)-confined concrete with inner steel tube have received researchers’ interest. This article presents the nonlinear finite element analysis and multiple machine learning (ML) model-based study on the behavior of round corner rectangular CFRP-confined concrete short columns reinforced by the inner high-strength elliptical steel tube under the axial load. The reliability of the proposed nonlinear finite element model was verified against the existing experimental investigations. The effects of the parameters such as the concrete grade, thickness of reinforcing steel tube, cross-sectional size of inner steel tube, and thickness of CFRP on the behavior of the columns are comprehended in this study. Furthermore, multiple ML models were proposed to predict the ultimate axial load, ultimate axial strain, and lateral strain of the test specimens. The reliability of the proposed ML models was evaluated by six distinct performance metrics. From the parametric investigation, it was found that concrete with lower compressive strength gained more strength enhancement because of confinement between CFRP and the inner steel tube than high-strength concrete relative to its unconfined compressive strength. The proposed ML models of extreme gradient boosting and random forest provided the best-fit results than the artificial neural network and Gaussian process regression models in predicting the axial load and axial and lateral strains of the columns.

Due to the expanding global population and rising per capita consumption, there has been an increase in the demand for environmentally friendly building materials in recent years. Moreover, the quest for steel and cement alternatives has become more crucial. Any substitute materials must be reasonably priced, fast growing, equivalent in the strength and characteristics, and environmentally friendly. In the current chapter, first, a tensile strength test was conducted on available bamboo strips to determine their ultimate strength and other engineering characteristics. Then, bitumen and epoxy resin were applied to bamboo to investigate the effects of two alternative adhesives on the bond resistance offered with the contact of the bamboo structural specimen. Moreover, experiments were performed on steel and bamboo-reinforced concrete beams to further study the load-carrying capacity, deflection, ductility, stiffness, and energy absorption. In addition, beams were subjected to a two-point stress test to examine how they respond to bending. These experiments indicated that when treated properly, bamboo can replace steel as structural reinforcement in concrete beams.

High-rise timber building construction is becoming increasingly common across the world as construction and woodworking technology advances. The world is moving toward more sustainable development, and products like cross-laminated timber offer economical options for reducing the environmental impact. This chapter contributes to the theory and practice of sustainability assessment and extends the knowledge about high-rise timber buildings. The tallest timber buildings in different countries, such as Mjøstårnet and Treet in Norway and Brock Commons in Canada, are compared across the three dimensions of sustainability (environmental, economic, and social). According to previous research, none of the buildings are at the top in terms of sustainability, but the Brock Commons building in Canada has received the highest rank in all dimensions of sustainability. The issue of fire resistance for timber structures involves a paradox because it is widely recognized that heavy timber construction has outstanding fire resistance in severe fires. Design for burnout may require full or partial encapsulation of timber. Moreover, prefabrication of elements reduces duration and cost of projects. The goal of this chapter is to evaluate and assess the most effective modern high-rise timber buildings from both financial and environmental perspectives.

Enhancing the durability of structural elements is a viable approach to promote sustainability in civil engineering. Research has shown that well-maintained slabs outperform degraded ones, which deteriorate rapidly due to insufficient upkeep. The occurrence of cracking and deformation in slabs subjected to sustained loads significantly impacts their functionality. However, the implementation of appropriate retrofitting techniques utilizing locally available materials can effectively minimize deflection and crack propagation while also improving flexural capacity. This particular study aimed to evaluate the flexural performance of slabs that were retrofitted using bamboo fibre laminate (BFL). Also, the study investigated two alternative replacement methods alongside the conventional mix; one involved replacing all fine aggregates with ceramic fine aggregate and the other involved a complete replacement of coarse aggregates with ceramic coarse aggregate. These mixes were represented in both the retrofitted and non-retrofitted samples. The retrofitting process included using the combined external bonding and near surface-mounted method. Twelve slab samples were made, with six being non-retrofitted and the other six retrofitted with BFL. Each of the samples had dimensions of 300 mm × 300 mm × 50 mm for reinforced concrete (RC) slabs. The slabs were tested employing the three point-bending system, and the retrofitted slabs with the conventional mix exhibited the highest ultimate failure load and flexural strength (62.1 kN), which compared to the non-retrofitted slabs of the same mix was a 60.76% increase. Additionally, the study did a thorough analysis of the presence of flexural and diagonal shear cracks, as well as the occurrence of debonding between BFL and the slabs. Non-destructive tests were also conducted on the slab samples to further confirm accurate results. These findings offer helpful insights into the development and application of a sustainable retrofitting

This study investigates the structural behaviour of double-skin columns, introducing novel double-skin double filled tubular (DSDFT) columns, which utilise double steel tubes and concrete to enhance the load-carrying capacity and ductility beyond conventional double-skin hollow tubular (DSHT) columns, employing a combination of finite element model (FEM) and machine learning (ML) techniques. A total of 48 columns (DSHT+DSDFT) were created to examine the impact of various parameters, such as double steel tube configurations, thickness of fibre-reinforced polymer (FRP) layer, type of FRP material, and steel tube diameter, on the load-carrying capacity and ductility of the columns. The results were validated against the experimental findings to ensure their accuracy. Key findings highlight the advantages of the DSDFT configuration. Compared to the DSHT columns, the DSDFT columns exhibited remarkable 19.54 % to 101.21 % increases in the load-carrying capacity, demonstrating improved ductility and load-bearing capabilities. Thicker FRP layers enhanced the load-carrying capacity up to 15 %, however at the expense of the reduced axial strain. It was also observed that glass FRP wrapping displayed 25 % superior ultimate axial strain than aramid FRP wrapping. Four different ML models were assessed to predict the axial load-carrying capacity of the columns, with long short-term memory (LSTM) and bidirectional LSTM models emerging as superior choices indicating exceptional predictive capabilities. This interdisciplinary approach offers valuable insights into designing and optimising confined column systems. It sheds light on both double-tube and single-tube configurations, propelling advancements in structural engineering practices for new constructions and retrofitting. Further, it lays out a blueprint for maximising the performance of the confined columns under the axial compression.

Nowadays, the application of nanotechnology has gained increased attention in the concrete technology field. Several applications of concrete require light weight; one such concrete used is foamed concrete (FC), which has more voids in the microstructure. In this study, nano-silica (NS) was utilized, which exhibits a pozzolanic nature, and it reacts with other pozzolanic compositions (like lime, alumina, etc.) to form hydrated compounds in concrete. Apart from these hydrated compounds, NS acts as a filler material and enhances properties of concrete such as the fresh and hardened properties. This research examines the fresh, hardened, and microstructural properties of FC blended with NS. The ratio of binder and filler used in this research is 1:1.5, with a water-to-binder ratio of 0.45 and a density of 880 kg/m3. A total of six different weight fractions of NS were added to FC mixes, namely 0%, 1%, 2%, 3%, 4%, and 5%. Properties assessed for FC blended with NS were the slump, bulk density, strength parameters (flexural, splitting tensile, and compressive strengths), morphological analysis, water absorption, and porosity. It was concluded from this study that the optimum NS utilized to improve the properties was 3%. Apart from this, the relationship between the mechanical properties and NS dosages was developed. The correlations between the compressive strength and other properties were analyzed, and relationships were developed based on the best statistical approach. This study helps academicians, researchers, and industrialists enhance the properties of FC blended with NS and their relationships to predict concrete properties from other properties.

Over the last decades, cement has been observed to be the most adaptive material for global development in the construction industry. The use of ordinary concrete primarily requires the addition of cement. According to the record, there has been an increase in the direct carbon footprint during cement production. The International Energy Agency, IEA, is working toward net zero emissions by 2050. To achieve this target, there should be a decline in the clinker-to-cement ratio. Also, the deployment of innovative technologies is required in the production of cement. The use of alternative binding materials can be an easy solution. There are several options for a substitute to cement as a binding agent, which are available commercially. Non-crystalline alkali-aluminosilicate geopolymers have gained the attention of researchers over time. Geopolymer concrete uses byproduct waste to reduce direct carbon dioxide emissions during production. Despite being this advantageous, its utilization is still limited as it shows the quasi-brittle behavior. Using different fibers has been started to overcome this weakness. This article emphasizes and reviews various mechanical properties of fiber-reinforced geopolymer concrete, focusing on its development and implementation in a wide range of applications. This study concludes that the use of fiber-reinforced geopolymer concrete should be commercialized after the establishment of proper standards for manufacturing.

I denne FRIC studien er den forebyggende effekten av Bjørnis for brannsikkerheten i norske husstander studert. Hovedkonklusjonen er at Bjørnis har ført til en tydelig og dokumenterbar forbedring av brannsikkerheten i norske hjem. Studien er utført som en del av prosjekt 4.3 Brannsikkerhetstiltak for boliger i FRIC, i samarbeid med Stiftelsen Brannbamsen Bjørnis. Det er også et webinar på norsk og engelsk som presenterer studien, opptak av webinaret vil bli publisert her: https://fric.no/publikasjoner. | In this FRIC study, the effect of the fire mascot Bjørnis on the fire safety in Norwegian households is studied. The main conclusion is that Bjørnis has led to a clear and documentable improvement of the fire safety in Norwegian homes. This study is a part of project 4.3 Fire safety measures for dwellings in FRIC, in collaboration with the Bjørnis Foundation. There is also a webinar in Norwegian and English presenting the study, the webinar recording will be published at: https://fric.no/en/publications.

Birch (Betula spp.) is a hardwood species with a wide natural distribution on the Eurasian continent, especially in northern Europe. Compared with conventional plywood made from softwood, birch plywood has favorable mechanical properties that could be used in new types of efficient connections for timber structures, and thus enable a substitution of current systems using slotted-in steel plates. Such new connections could result in significant advantages in terms of environmental impact and economy as well as ease of prefabrication and assembly. However, birch plywood has rarely been utilized in connections, and therefore, there is a lack of knowledge necessary to design safe timber structures applying such connection systems. In particular, there is a need for increased knowledge of the mechanical properties of birch plywood and its structural performance under various loading conditions. Current connections in timber structures usually also involve mechanical fasteners, e.g., steel screws and dowels, but there is limited use of adhesively bonded (glued) connections. The aim of this thesis is to gain new knowledge required for the development of adhesively bonded connections using birch plywood as gusset plates in structural applications. Examples of such structural applications are timber trusses and portal frames. In this context it is necessary, first, to characterize the in-plane mechanical properties of birch plywood, and second, to investigate its performance in adhesively bonded connections. The results of the mechanical testing show that birch plywood possesses the highest and lowest tensile, compressive, and bending strength and elastic modulus at 0° (parallel) and 45°, respectively, to the face grain (the fiber direction of the face veneers). The opposite findings were noticed for the shear strength and the shear modulus. All these strength values are similar to or higher than the corresponding strength values of common softwood structural timber in its, Björk (Betula spp.) är ett lövträdslag med bred naturlig utbredning på den Eurasiska kontinenten, särskilt i norra Europa. Jämfört med konventionell plywood tillverkad av barrträ har björkplywood gynnsamma mekaniska egenskaper som skulle kunna användas i nya typer av effektiva förband för träkonstruktioner och därmed möjliggöra en substituering av nuvarande system med inslitsade stålplåtar. Sådana nya förband kan resultera i betydande fördelar vad gäller miljöpåverkan och ekonomi samt enkel prefabricering och monterbarhet. Dock har björkplywood sällan använts i förband, och därför saknas kunskap som krävs för att utforma säkra träkonstruktioner med sådana förbandsystem. I synnerhet finns det ett behov av ökad kunskap om de mekaniska egenskaperna hos björkplywood och dess strukturella beteende under olika belastningsförhållanden. Nuvarande förband i träkonstruktioner involverar också vanligtvis mekaniska fästelement, t.ex. stålskruvar och -dymlingar, medan användningen av limmade förband är begränsad. Syftet med denna avhandling är att ta fram ny kunskap nödvändig för en utveckling av limmade förband med skivor av björkplywood i bärande träkonstruktioner. Exempel på sådana träkonstruktioner är fackverk och portalramar. I detta sammanhang är det nödvändigt att dels karaktärisera de mekaniska egenskaperna i planet hos björkplywood, dels att undersöka dess prestanda i limmade förband. Resultaten av de mekaniska testerna visar att björkplywood har den högsta och lägsta drag-, tryck- och böjhållfastheten och elasticitetsmodulen vid 0° (parallellt med) respektive 45° relativt ytfanérens fiberriktning. De motsatta resultaten noterades för skjuvhållfastheten och skjuvmodulen. Alla dessa hållfasthetsvärden är liknande eller högre än de motsvarande hållfasthetsvärdena för vanligt konstruktionsvirke av barrträ i dess längdriktning. Dessutom observerades en storlekseffekt för böjhållfastheten i planet vid 0° och 90° relativt ytfibrerna men inte vid andra vinklar, vilket tillsk, QC 20240314

The rapid urbanization process is majorly associated with extreme climate change and many other urban issues that pose new challenges in terms of urban resilience. Bold climate action is one of the main principles addressed by UN-Habitat in Sustainable Development. This problem demands an immediate reduction in carbon footprints. One way of doing this is to revive the traditional climate-controlling techniques/natural ventilation methods in architecture. Windcatchers have been used as a passive technique for ventilation for many centuries. The windcatchers of Hyderabad (Mangh/Hawadani/Badgeers/Malqaf) were a dominant identity of vernacular architecture. This article aims to understand the traditional methods of dealing with climate-controlling techniques in architecture by (1) studying windcatchers in both vernacular and modern buildings in the context of Hyderabad, Sindh, Pakistan by (2) understanding the user’s perspective about windcatchers. A comparison of four buildings in Hyderabad, Pakistan, was performed. The findings of this study show that old Windcatchers in Hyderabad are in dilapidated condition and are found insignificant because they are not fulfilling the current needs of the users looking for modernized solutions. However, newly built windcatchers are well appreciated by users because of their well-functioning mechanism in relation to the local climate and current living requirements. The performance study of windcatchers conducted in this research represents an initial step towards developing a more extensive guide for utilizing windcatchers in passive cooling systems for buildings located in hot regions.

Wind-induced single-sided ventilation is a prevalent form of natural ventilation extensively used in buildings. Nevertheless, prior experimental investigations predominantly focused on single-zone buildings, neglecting the multizone buildings with internal partitions which is representative of more common scenarios. This study addresses this gap by investigating the impact of internal partitions on single-sided ventilation, employing a combination of wind tunnel experiment and numerical analysis. Airflow rate (AFR) was measured with a split-fibre probe and purging flow rate (PFR) was assessed by the tracer gas methodology. The PFR exhibits greater sensitivity to internal partitions in unidirectional airflow compared to bidirectional flow. Large Eddy Simulation (LES) was conducted to elucidate the intricate airflow characteristics in single-sided ventilation. The ventilation efficiency (ratio of PFR and AFR) derived from LES ranges between 0.74 and 0.79, which means that <80% of the AFR actively contributes to the removal of contaminants. Notably, the investigation discerned that the AFR of a single room approximates that of the entire room, whereas the PFR of a single room is smaller than that of the whole room. The disparities in AFR and PFR were caused by the recirculating flow, which was elaborated by the theoretical analysis.

There is still insufficient data on the behavior of tubed-reinforced concrete columns (TRCCs) under the eccentric compression. Thus, this research work comprehensively examines the eccentric compression behavior of TRCCs using nonlinear finite element modeling and machine learning (ML). To do this, numerical simulation and parametric analysis based on existing investigations were conducted. In addition to the existing 22 specimens with limited test variables, additional 188 specimens were developed to cover a wide range of parameters, including the load eccentricity, transverse reinforcement spacing, columns’ slenderness ratio, yield strength of steel, and outer steel tube diameter. Additionally, six ML models were created to estimate the ultimate load results. The results indicated that increasing the outer steel tube yield strength and diameter, and reducing the load eccentricity, slenderness ratio, and spacing of the transverse reinforcement enhanced the load-carrying capacity of the columns. The Gaussian process regression model demonstrated superior performance metrics in comparison to other ML models, with the highest R2 values (0.998613 in training and 0.99823 in testing stages) and lowest root mean square error values (0.007213 in training and 0.008471 in testing stages). To save money, time, and resources compared to laboratory testing, an online-based prediction program is finally presented to predict the columns’ ultimate load.

Modern railway infrastructures, especially bridges, are exposed to significant vibrations with potential safety implications. In this context, previous studies have shown the inconsistency and inadequacy of some conventional design methods necessitaing them to be improved. The assessment of safety inherently deals with uncertainties. Therefore, the current study is dedicated to this objective using reliability-based methods. Of the various possible failure modes, the investigations presented here are limited to running safety and passenger comfort. The investigation of these limit-states requires constructing complex computational models with train-track-bridge interaction capabilities. However, the application of these computationally intensive models in the context of structural reliability does not appear to be feasible. Simplifying the system, the vertical acceleration and the deflection of the bridge serve as implicit limit-state measures. Initially, using First Order Reliability Method (FORM) revealed limitations in the application of the current safety factor, resulting in inconsistent reliability indices. Therefore, probabilistic design curves are proposed, defining minimum required bridge mass and stiffness based on cross-section types, span configurations and train speeds. These results are obtained by formulating a FORM-based optimization. Subsequently, the results are used to investigate the sensitivity of the estimated failure probabilities with respect to the contributing basic random variables. Acknowledging the limitations of FORM, surrogate-assisted simulation-based reliability assessments were used for further investigations. A comparison of the performance of widely used regression-based surrogate models under an identical active learning scheme showed the superior performance of the Kriging method over the others. Within areliability-based design optimization framework, this Kriging model facilitates the generation of new probabilistic design cur, Moderna järnvägsbroar utsätts för betydande säkerhetsrelaterade vibrationer. Tidigare studier har visat att vissa konventionella dimensioneringsmetoder är inkonsekventa och otillräckliga, vilket kräver förbättringar. Säkerhetsbedömning handlar i grunden om osäkerheter. Därför ägnas den föreliggande studien åt detta mål med hjälp av tillförlitlighetsbaserade metoder. Undersökningarna här begränsas till trafiksäkerhet och passagerarkomfort som möjliga dimensioneringsvillkor. Undersökningen av dessa gränstillstånd kräver komplexa beräkningsmodeller som beaktar tåg-spår-bro-interaktion. Att använda beräkningsintensiva modeller för strukturell tillförlitlighet verkar inte genomförbart. Genom förenklingar av systemet kan vertikal acceleration och nedböjning ansättas som mått för implicita gränsvillkor. Inledningsvis visade användningen av första ordningens tillförlitlighetsmetod (FORM) begränsningar i tillämpningen av nuvarande säkerhetsfaktor, vilken resulterade i inkonsekventa säkerheter. För att adressera detta föreslås probabilistiska dimensioneringskurvor, som definierar minsta erforderliga bromassa och styvhet baserat på tvärsnittstyper, spannkonfigurationer och tåghastigheter. Dessa resultat erhålls genom att formulera en FORM-baserad optimering. Därefter används resultaten för att undersöka känsligheten hos de uppskattade brottsannolikheterna med avseende på de ingående grundläggande stokastiska variablerna. Med tanke på begränsningarna med FORM användes simulering-baserade tillförlitlighetsbedömningar med hjälp av surrogatmodeller för fortsatta undersökningar. I en jämförelse av kända regressionsbaserade surrogatmodeller, under identiska inlärningsförutsättningar, visade Kriging-metoden överlägsen effektivitet. Inom ramen för en tillförlitlighetsbaserad optimering underlättar denna Kriging-modell framtagningen av nya probabilistiska designkurvor. Detta uppnås genom en ny formulering av metoden där korrelationen mellan de stokastiska variablerna beaktas med hjälp, QC 240325, IN2TRACK2, IN2TRACK3, IAM4RAIL

Trafikverksskolans årsrapport för 2023

Trafikverkets årsredovisning för 2023

Årsrapport för forskning och innovation 2023. Beskriver verksamheten i siffror samt en sida med fördjupning per område/portfölj.

A major issue in current strategic planning is how local ambitions to achieve growth should be balanced against interlinked national and global targets for climate and environment. This competition between local and cross-boundary issues are of vital importance to highlight considering that all spatial planning is local in some regard. The Swedish spatial planning system allows for a great deal of self-determination among the local municipalities. Research indicates that the municipalities first and foremost gives consideration to local environmental issues in regards to their strategic planning. This creates a potential conflict between local and non-local interests leading to a deprioritization of national planning interests. Considering these issues the Swedish spatial planning system should be examined to identify its potential structual weaknesess. Towards this end the essay examines a case-study of expanding cross-border trade in the municipality of Strömstad using discourse analysis. Using this the essay maps how perspectives on cross-border trade among the participating actors has shaped the planning process. The esseay has a broad approach covering issues of politics, economics and environemnt to capture how these issues interlink and affect each other. The essay reveals that the planning process has been characterized by an informal co-operation between the municipality and the corporate interests that stands to gain from the expanded border trade. Private companies that do not stand to gain from the municipal planning strategy are excluded from the informal process. The informally participating companies finance part of the planning process and are expected to finance the investments in infrastructure which will be required to realize the planning strategy. This indicates that the process of strategic spatial planning has taken on some characteristics of the processes in Swedish planning usually reserved for developing detailed development plans for speci

In an era of rapidly advancing lighting technology and evolving public library roles, this study introduces a groundbreaking strategy for human-centric and integrative lighting asset management. Embracing both visual and non-visual effects, “integrative lighting” aims to enhance users’ physiological and psychological well-being. Despite technological progress, notably with LEDs, current asset management often lags, relying on reactionary measures rather than proactive strategies. As public libraries transform into dynamic learning hubs, the significance of indoor lighting, impacting both physical health and holistic well-being, cannot be understated. Yet, many existing solutions are based on controlled lab tests, bypassing the diverse real-world needs of public libraries. Aiming to explore and develop human-centric and integrative lighting asset management strategies to optimize lighting environments in public libraries, this research offers a cohesive approach encompassing context identification, a management framework, and a maturity assessment model. Additionally, this study highlights the synergy between the role of the lighting asset manager, ISO 55000 principles, and these foundational strategies. This holistic approach not only reinvents lighting in public libraries but also aligns it with the broader Sustainable Development Goals (SDGs), advocating for light as a conduit of comprehensive human betterment. The current study is primarily qualitative in nature. While this study is based on public libraries in Nordic countries, the implications and findings can be of interest and value to a broader international audience.

This paper reviews digital tools for supporting the Circular Economy (CE) in the built environment. The study provides a bibliometric analysis and focuses on computer-aided design (CAD), building information modeling (BIM), and computational plugins that can be used by practitioners. While Life Cycle Assessment (LCA) is the primary methodology for evaluating buildings' environmental performance, the study identifies tools beyond LCA, including computational methods and circularity indicators, that can support the evaluation of circular design strategies. Our review highlights limitations in tools’ functionalities, including a lack of representative data for LCA and underdeveloped circularity indicators. The paper calls for further development of these tools in terms of interoperability aspects, integration of more sources of data for LCA and circularity, and possibilities for a comprehensive evaluation of design choices. Computational plugins offer greater flexibility, while BIM-LCA integrations have the potential to replace dedicated LCA software and spreadsheets. Additionally, the study identifies opportunities for novel digital methods, such as algorithms for circular design with various types of reused building elements, and sharing of digital twins and material passports. This research can inform future studies and support architects and engineers in their efforts to create a sustainable built environment., QC 20231204, ReCreate project (Horizon 2020 grant no. 958200)

This chapter discusses recent trends in management of postuse wood products and gives an overview of benefits and constraints associated with effective end-of-life management of wood. It highlights the implications of postuse wood management from resource efficiency and climate perspectives. Primary energy and GHG balances are important metrics to understand the resource efficiency of climate change mitigation strategies involving postuse wood products. The chapter describes mechanisms through which postuse management of recovered wood materials can affect primary energy use and GHG impacts of wood products. To further understand the implications of different postuse management options for wood products, we then explore several quantitative scenarios. There is potential for efficient management of postuse wood products by directing these resources to cascade uses including reuse, recycling, and energy recovery. This can offer significant opportunities to improve resource efficiency and reduce greenhouse gas emissions in the built environment.

A convertible, zoned ventilation system was field-tested in a modern, airtight Swedish home when occupied either by an experimental team or by a family. Indoor air quality in the master bedroom was monitored under four ventilation strategies. Relative to constant air volume strategies (CAV), demand-controlled ventilation (DCV) that was responding to CO2 concentration extracted more air when people were present, but less in total over 24 h. This elevated the indoor air humidity, beneficial in climates with dry winter air. Multiple monitors within the bedroom indicated that vertical CO2 stratification occurred routinely, presumably due to low mixing of supply air from a wall-mounted diffuse vent, spreading the air radially over the wall. This seemingly improved air quality in the breathing zone under local (ceiling) extract ventilation but worsened it during more typical, centralised extract ventilation, where air escapes the room via an inner doorway. The local extract arrangement thus seemed to yield both improved ventilation efficiency and reduced contaminant spread to other rooms. The noted air quality variations within the room highlight the importance of sensor placement in demand-control ventilated spaces, even in small rooms such as bedrooms.

The significant impact of the built environment on resource consumption and waste production has led to calls for a shift towards a circular economy model that maximizes the efficient use of resources. This study explores the use of digital product passports (DPPs) to improve how we manage products throughout their lifecycle. However, dealing with the complexity and large volume of data in DPPs can be challenging in terms of effective information management and utilization. We address this issue by adopting a modular ontological approach to systematically capture product lifecycle information from its origin to its end-of-life phase. To ensure interoperability and reusability of the ontology, we annotate key concepts and relationships using International Organization for Standardization (ISO) standards that promote circular economy. Our research led to the development of several ontology modules derived from literature reviews and interviews conducted with industry and academia experts who specialize in sustainability. These modules were then integrated to create a digital product passport ontology. The study demonstrates the feasibility of using a modular ontology approach to manage the complex information inherent in DPPs paving the way for more sustainable management practices in the built environment sector.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:200 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:200 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:350 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:600 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Den omfattar Uppsala, Västmanlands, Södermanlands, Gävleborgs, Dalarnas. Värmlands och Örebro län. Kartan är i skala 1:500 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:250 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:250 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:200 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:250 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:500 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods., Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Kartan är i skala 1:250 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Den omfattar Västernorrlands, Norrbottens, Västerbottens och Jämtlands län. Kartan är i skala 1:750 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Den omfattar Stockholms och Gotlands län. Kartan är i skala 1:300 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods. Den omfattar Hallands och Västra Götalands län. Kartan är i skala 1:250 000, Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.

Kartan innehåller bland annat uppgifter om allmänna vägnätet med bärighetsklasser, framkomlighetsbegränsningar, rekommenderade färdvägar för transporter med farligt gods, förbudsvägar och förbudsområden för transporter med farligt gods., Kartan är en nedladdningsbar pdf. Den finns inte att köpa i tryckt format.