| 21. |
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| 22. |
- Alvarez, Manuel, 1980-
(författare)
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Distribution Network Planning Considering Capacity Mechanisms and Flexibility
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The increasing penetration of distributed energy resources (DERs) has posed challenges to the distribution system operator (DSO) from the operation and regulatory point of view. High penetration of DERs could have negative impacts on the performance of the distribution grid, and depending on the regulatory framework, the DSO's remuneration as well. In liberalized electrical systems, the focus on promoting eciency has led to the implementation of an incentive-based regulation that exerts additional pressure on the DSOs to reduce costs. Additionally, the European Parliament Directive 2009/72/EC establishes a regulatory unbundling among the distribution, production, and retailing activities within the same vertically integrated electric utility.A way of helping the DSO to cope with the posed challenges is by providing it with exibility. This exibility can be acquired from the planning stage, and later be used during the system operation. This exibility can stem from the DSO's ability to exert control on the demand and the supply side to balance the system and correct its operational state.Based on the European DSOs' current situation at facing the increasing penetration of DERs, this thesis investigates in non-wired exible grid tools to solve the distribution network expansion problem. The investigation focuses on exibility providers, in particular on energy storage systems and hydropower, and also on capacity mechanisms to translate the capacity from DERs into the grid's capacity for planning purposes.Given that the share of renewable sources among the DERs is increasing, and considering the importance of energy storage systems in providing exibility to balance renewable energy production, the eort has been turned on to developing a hydropower model and a generic storage model that t both planning and operational studies.Given the need for gearing the DERs' behavior into the DSO's decision making process during the planning and operational timescales, the design and implementation of a distribution capacity mechanism have been developed. The design of the capacity mechanism has been conceived considering its integration within the distribution network expansion problem.The outcomes of this thesis can be synthesized as follows: 1) A generic hydraulic/storage model provided with an equivalent marginal cost that aids in considering the impact of present decisions in the future costs. 2) A market oriented distribution capacity mechanism that gears DERs and the DSOs to benefit mutually. 3) A distribution network expansion planning formulation that integrates the capacity resource from DERs through the distribution capacity mechanism.
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| 23. |
- Amiri, Kaveh
(författare)
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Experimental investigation of a Kaplan runner under steady-state and transient operations
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hydropower is a key part in electricity production nowadays. Hydropower electricity production rose to 3579.5 TWh in 2013, ranked as the second source of electricity production in the world after fossil fuels. It is the principle source of renewable electricity production, producing 16.2% of the electricity in 2013, accounting for 78% of the renewable electricity production in the world. Specifically in Sweden, hydropower is the main source of electricity production producing 47.5% of the required electricity. Nuclear, biomass, and wind placed in the following positions in the ranking in 2013 with 38.4%, 6.5%, and 4.3%, respectively.Besides meeting electricity demand with an environmental-friendly method, hydropower has a unique and important role which is grid regulation: balancing electricity production and consumption. Gas turbines and hydraulic turbines called “Primary reserves” are the only electricity production systems that can be used for fast regulations due to their short start-up time from 1 to 60 s. The obvious environmental problems, air pollution, and costs associated with gas turbines make hydropower a prime alternative whenever applicable. In Sweden, the share of fossil fuels in electricity production is small; 2.8% in 2012 with an average annual growth of -0.7% in the period 2002-2012. Hence, hydropower is practically the only available source used to regulate the grid fluctuations resulting from deregulated market and fast growth of intermittent power generation systems, i.e., solar and wind energy. Hydraulic turbines are subject to frequent off-design and transient operations because of their grid regulation responsibility. Such operating conditions decrease turbine’s efficiency and affect its lifetime significantly. Off-design and transient operation of hydraulic turbines may induce unpredicted pressure fluctuations on the stationary and rotating parts of the turbine. Special attention should be dedicated to the effects of such phenomena on the runner blades because of their importance on the efficiency of the turbine, and their vulnerability to the pressure fluctuations.This thesis presents an experimental investigation on the effects of off-design and transient operation of an axial hydraulic turbine on velocity fields and pressure fluctuations exerted on the runner and the draft tube of a turbine. The investigation was performed on a 1:3.1 scaled model of a Kaplan turbine known as Porjus U9. The main objective was to investigate the effect of operating point on pressure and velocity fluctuations in the runner and the draft tube. Another objective was to study the effect of transient operation on pressure fluctuations exerted on the runner and the draft tube, to investigate the formation and mitigation process of a rotating vortex rope (RVR) within the draft tube. Finally, the effect of the swirl leaving the runner and the draft tube bend on the performance of the turbine was investigated. The study involves pressure measurements on the runner blades and draft tube walls of the turbine, laser Doppler anemometry (LDA) measurements within and after the runner, and particle image velocimetry (PIV) measurements within the draft tube.The pressure and LDA results acquired during steady state operation of the turbine showed different sources of fluctuations on the runner at different operating points resulting in symmetric and asymmetric fluctuating forces on the runner. The pressure measurements during transient operating conditions exhibited pressure fluctuations exerted on the runner during load variations and elucidated some aspects of formation and mitigation process of RVR within the draft tube. The PIV measurements performed after the draft tube bend of the turbine focuses on the physical phenomena resulting in flow asymmetry after the draft tube bend of hydraulic turbines affecting their efficiency.
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| 24. |
- Anders, Viking
(författare)
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Institutional complexity in Swedish built environment regulation : exploring the interface with industrialized house-building
- 2017
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The industrialized house-building movement has emerged as aresponse to recurring criticism of the construction sector. It seeks toemulate management practices prevalent in manufacturing industries,including the use of standardized work processes and building systems.This approach does, however, make industrialized house-buildingcontractors susceptible to unpredictable variations. Swedish localplanning authorities have a legal and democratic mandate to regulatethe built environment within its borders and views variations betweendifferent municipalities as a desirable consequence of a functional localdemocratic system. Meanwhile, industrialized house-buildingcontractors have highlighted variations in regulation of the builtenvironment as obstructive to their intended methods of managing thebuilding process. The aim of this thesis is to increase understanding ofhow local planning authorities make interpretations when regulatingthe built environment and how those interpretations influenceindustrialized house-building contractors and to, within the ongoingresearch process, identify theoretical perspectives suitable for describingtensions in the interface between industrialized house-building andlocal planning authorities. The theoretical frame of reference for thisthesis consists of two major streams of organizational literature:organizational coordination, operationalized though the concept ofcoordination mechanisms, and neo-institutional theory, operationalizedthrough institutional logics and institutional complexity. Theoverarching research strategy is best described as a case study approachinvestigating cases of institutional complexity in regulation of theSwedish built environment. The design consists of one multi-casestudy relying on interviews with representatives of industrializedhouse-building contractors and local planning authorities and onesingle-case study investigating a longitudinal land development processusing a combination of interviews, direct observations and documentanalysis. Findings indicate that local planning authorities faceinstitutional complexity stemming from three semi-compatibleinstitutional logics that each prescribe different roles for planningpractitioners and expectations for their behaviour. As some planningpractitioners are more attuned to particular logics than others, it is difficult to predict, for each given situation, which logic will beactivated. Furthermore, findings indicate that institutional logics can beviewed as coordination mechanisms, thereby highlighting afundamental tension between the coordination preferences ofindustrialized house-building contractors and local planning authorities.This tension causes a lack of accountability, predictability and commonunderstanding resulting in an inability for industrialized house-buildingcontractors and local planning authorities to coordinate theircontributions in the planning and building process. The findings implythat industrialized house-building contractors and local planningauthorities should attempt to acknowledge each other’s participation inand contributions to the planning and building process. The findingsalso highlight the importance of interpretations for regulation of thebuilt environment, which implies that not all sector-wide problems canor need be solved through legislative action.
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| 25. |
- Andersson, Jim
(författare)
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Systems Analysis of Chemicals Production via Integrated Entrained Flow Biomass Gasification : Quantification and improvement of techno-economic performance
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Lignocellulosic biomass gasification is a promising production pathway for green chemicals, which can support the development towards a more sustainable society where fossil fuels are replaced. To be able to compete with fossil fuels, a highly efficient production of biomassbased products is required in order to maximize overall process economics and to minimizenegative environmental impact. Large production plants will likely be required to obtain favourable economy-of-scale effects and reasonable production cost. Entrained flow gasification (EFG) is a favourable technology due to its suitability for large-scale implementation and ability to produce a high quality syngas from various biomass feedstocks. In order to estimate overall energy efficiency and production costs for gasification-based biorefineries, it is important to be able to characterise the gasifiers’ performance. This in turnrequires reliable estimations of the gasification process. Integration of EFG-based biorefineries with existing pulp mills or other large-scale forestindustries can be achieved by integration of material and/or energy flows, as well as by coutilisation of process equipment. This could potentially induce both technical and economic added-values. At chemical pulp mills, an important feedstock for green chemical production may be the black liquor from the pulp production, since it provides an attractive combinationof advantages. The black liquor availability is, however, directly correlated to the pulp production (i.e. the mill size) and the potential green chemical production volume via pure black liquor gasification (BLG) is therefore limited.In this thesis, two systems are considered that expand on the BLG concept with the intent to increase the chemical production volume, since this could generate positive economy-of-scale effects and is a rather unexamined area. In addition to this, an EFG configuration entailing a lower availability related risk for the considered host pulp mill is also considered. The threeconsidered integrated systems are: (i) co-gasification of biomass-based pyrolysis oil blended with black liquor for methanol production, (ii) parallel operation of BLG and solid biomass EFG for methanol or ammonia production, and (iii) replacing the bark boiler with solid biomass EFG for methanol or ammonia production. These system solutions establish a combination of material, energy and equipment integration. The main aim of this thesis is to increase the knowledge of the characteristics of entrained flow biomass gasification systems and their opportunities for integration in existing industries for production of green chemicals (methanol and ammonia). An appropriate modelling framework that combines chemical modelling on a high level of detail with holistic industrial site modelling is designed and used to identify and quantify energetic and economic addedvalues for the integrated biorefineries. Mathematical process integration models based on Mixed Integer Linear Programming (MILP) of pulp mills are used to study integration of the biomass gasification systems with the mills. An iterative modelling approach is applied between the process integration model and the detailed biomass gasification models based on Aspen Plus or a Matlab-based thermodynamic equilibrium model. As a complement to themodelling framework, a multi-scale equivalent reactor network (ERN) solid biomass-based EFG model is developed to be able to identify and study influential parameters on the gasifiers’ performance in the Aspen Plus platform. This is approached by considering the effect of mass and heat transfer as well as chemical kinetics. The results show that replacing a recovery or a bark boiler with EFG for green chemicals production improves the overall energy system efficiency and the economic performance,compared to the original operation mode of the mill as well as compared to a stand-alone gasification plant. Significant economy-of-scale effects can be obtained from co-gasification of black liquor and pyrolysis oil. Co-gasification will add extra revenue per produced unit of methanol and reduces the production cost significantly compared to gasification of pure pyrolysis oil. In general, integrated EFG systems producing methanol sold to replace fossilgasoline are shown to constitute attractive investments if the product is exempted from taxes. Ammonia produced via EFG is per unit of produced chemical significantly more capital intense than the corresponding system producing methanol. The economic viability in the considered ammonia configurations is therefore found to be lower compared to methanol.The ERN model is shown to be able to estimate key performance indicators such as carbon conversion, cold gas efficiency, syngas composition, etc. for a real gasification process, showing good agreement with experimental results obtained from a pilot scale gasifier. This simulation tool can in future work be implemented in more global models to study and use to improve the techno-economic performance of EFG-based biorefineries, by quantifying theinfluence of important operational parameters. The main conclusion from this work is that production of green chemicals from biomass EFG integrated with a pulp mill is techno-economically advantageous compared to stand-alonealternatives. It is also concluded that the pulp mill size will be decisive for what integration route is the most favourable. Integration of an individual BLG plant with a pulp mill of maximum size would be the most economically beneficial alternative. However, the possibility to increase the green chemical production from a given black liquor volume improves the viability for integration in smaller mills. Increasing the production volume would therefore result in the highest efficiency and economic benefits given mill sizes up to300 kADt/y. From a resource perspective, this would however lead to an increased demand for biomass import to the mill, and this expansion could be limited by the overall availability of biomass resources.Keywords: Pulp mills, integration, biomass, gasification, green chemicals, methanol, ammonia.
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| 26. |
- Andersson, Ninnie
(författare)
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Communication and Shared Understanding of Assessment : A phenomenological study of assessment in Swedish upper secondary dance education
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The aim of this study is to describe and explore the phenomenon of assessment in dance education within the Swedish upper secondary schools’ dance orientation. The phenomenon was researched based on teachers’ experiences of assessment in dance education and formulations in the syllabi for upper secondary school. Life-world phenomenology constituted a base for the study. The methods used in the investigation were document analysis, observations, teachers’ written and verbal reflections and interviews. Documentation of observations was made through field notes, video recordings and sound recordings. The generated material was analysed based on Spiegelberg’s (1960) seven stages of phenomenological analysis. Syllabi from Lpf94 and Gy11 were researched to describe and analyse in what ways dance knowledge becomes visible. In total, five teachers and three schools were involved in the study. Within the framework of the course Dance technique 1, observations of dance education in ballet, contemporary- and jazz dance were made as well as of ten grade conferences. The teachers read the field notes and were able to change formulations in case something was misunderstood or it needed to be commented on in the form of teachers’ written or verbal reflections. Interviews with four of the observed teachers were made and the conversations related to what appeared in the observations. Comprehension of teachers’ experiences resulted in a description of the phenomenon and answers to the research questions. The study is communicated through four intertwined papers. The result reveals various conditions for assessment in dance education. Two themes appeared in the overall findings of the study, namely: The design of the assessment practice and Communication within the assessment practice. The syllabi appeared as one condition among others for dance education in upper secondary school including views of dance knowledge that appeared through analysis of the syllabi. In the assessment practice, it was seen that teachers’ conduct of assessment involved conditions for formative assessment to emerge. Conditions in order for communicated assessment to become meaningful for the students also emerged, including shared understanding. The teachers expressed various conditions for the assessment practice to became visible, namely the students’ participation, their own actions, as well as the overall school context. The study contributes to the dance educational research field through making teachers’ experiences of assessment in Swedish dance education visible. The thesis discusses dance teachers’ various approaches to syllabi, how the teachers’ conceptions of quality influence the assessment practice, and finally the importance of shared understanding of communicated assessment is emphasised. Furthermore, collegiate discussions are brought to the attention as a way to improve and reflect upon assessment.Keywords: upper secondary school, dance education, assessment, life-world phenomenology
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| 27. |
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| 28. |
- Antonopoulou, Io, 1989-
(författare)
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Development of biocatalytic processes for selective antioxidant production
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Feruloyl esterases (FAEs, EC 3.1.1.73) represent a subclass of carboxylic acid esterases that under normal conditions catalyze the hydrolysis of the ester bond between hydroxycinnamic acids (ferulic acid, sinapic acid, caffeic acid, p-coumaric acid) and sugar residues in plant cell walls. Based on their specificity towards monoferulates and diferulates, substitutions on the phenolic ring and on their amino acid sequence identity, they have been classified into four types (A-D) while phylogenetic analysis has resulted in classification into thirteen subfamilies (SF1-13). Under low water content, these enzymes are able to catalyze the esterification of hydroxycinnamic acids or the transesterification of their esters (donor) with alcohols or sugars (acceptor) resulting in compounds with modified lipophilicity, having a great potential for use in the tailor-made modification of natural antioxidants for cosmetic, cosmeceutical and pharmaceutical industries. The work described in this thesis focused on the selection,characterization and application of FAEs for the synthesis of bioactive esters with antioxidant activity in non-conventional media. The basis of the current classification systems was investigated in relation with the enzymes’ synthetic and hydrolytic abilities while the developed processes were evaluated for their efficiency and sustainability.Paper I was dedicated to the screening and evaluation of the synthetic abilities of 28 fungal FAEs using acceptors of different lipophilicity at fixed conditions in detergentless microemulsions. It was revealed that FAEs classified in phylogenetic subfamilies related to acetyl xylan esterases (SF5 and 6) showed increased transesterification rates and selectivity. In general, FAEs showed preference on more hydrophilic alcohol acceptors and in descending order to glycerol > 1-butanol > prenol. Homology modeling and small molecule docking simulations were employed as tools for the identification of a potential relationship between the predicted surface and active site properties of selected FAEs and the transesterification selectivity.Papers II- IV focused on the characterization of eight promising FAEs and the optimization of reaction conditions for the synthesis of two bioactive esters (prenyl ferulate and L-arabinose ferulate) in detergentless microemulsions. The effect of the medium composition, the donor and acceptor concentration, the enzyme load, the pH, the temperature and the agitation on the transesterification yield and selectivity were investigated. It was observed that the acceptor concentration and enzyme load were crucial parameters for selectivity. Fae125 (Type A, SF5) iiexhibited highest prenyl ferulate yield (81.1%) and selectivity (4.685) converting 98.5% of VFA to products after optimization at 60 mM VFA, 1.5 M prenol, 0.04 mg FAE mL-1, 40oC, 24 h, 53.4:43.4:3.2 v/v/v n-hexane: t-butanol: 100 mM MOPS-NaOH pH 8.0. On the other hand, FaeA1 (Type A, SF5) showed highest L-arabinose ferulate yield (52.2 %) and selectivity (1.120) at 80 mM VFA, 55 mM L-arabinose, 0.02 mg FAE mL-1, 50oC, 8 h, 19.8: 74.7: 5.5 v/v/v n-hexane: t-butanol: 100 mM MOPS-NaOH pH 8.0.In paper V, the effect of reaction media on the enzyme stability and transesterification yield and selectivity was studied in different solvents for the synthesis of two bioactive esters: prenyl ferulate and L-arabinose ferulate. The best performing enzyme (Fae125) was used in the optimization of reaction conditions in the best solvent (n-hexane) via response surface methodology. Both bioconversions were best described by a two-factor interaction model while optimal conditions were determined as the ones resulting in highest yield and selectivity.Highest prenyl ferulate yield (87.5%) and selectivity (7.616) were observed at 18.56 mM prenol mM-1VFA, 0.04 mg FAE mL-1, 24.5 oC, 24.5 h, 91.8: 8.2 v/v n-hexane: 100 mM sodium acetate pH 4.7. Highest L-arabinose ferulate yield (56.2%) and selectivity (1.284) were observed at 2.96 mM L-arabinose mM-1VFA, 0.02 mg FAE mL-1, 38.9 oC, 12 h, 90.5: 5.0: 4.5 v/v/v n-hexane: dimethyl sulfoxide: 100 mM sodium acetate pH 4.7. The enzyme could be reused for six consecutive reaction cycles maintaining 66.6% of its initial synthetic activity. The developed bioconversions showed exceptional biocatalyst productivities (> 300 g product g-1FAE) and the waste production was within the range of pharmaceutical processes.Paper VI focused on the investigation of the basis of the type A classification of a well-studied FAE from Aspergillus niger(AnFaeA) by comparing its activity towards methyl and arabinose hydroxycinnamic acid esters. For this purpose, L-arabinose ferulateand caffeate were synthesized enzymatically. kcat/Kmratios revealed that AnFaeA hydrolyzed arabinose ferulate 1600 times and arabinose caffeate 6.5 times more efficiently than methyl esters. This study demonstrated that short alkyl chain hydroxycinnamate esters which are used nowadays for FAE classification can lead to activity misclassification, while L-arabinose esters could potentially substitute synthetic esters in classification describing more adequately the enzyme specificitiesin the natural environment.
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| 29. |
- Asplund, Matthias
(författare)
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Wayside Condition Monitoring System for Railway Wheel Profiles : Applications and Performance Assessment
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The railway is an important mode of transport, due to its environmental friendliness, high safety level, and low energy consumption combined with a high transport capacity, among other factors. The Swedish railway network is old, there has been almost no expansion of the network during the past few decades, and more traffic is expected. Therefore, there is currently a demand for more track capacity and, in the short term, the existing network is expected to deliver the increased capacity. The railway operators in the network have a large impact on train delays, and wheel failures are one large contributor of delays. Delays destroy capacity and, therefore, capacityconsuming failures, such as abnormal wheels, need to be minimised. This can be achieved by using appropriate condition monitoring for the wheels on the track to find potential capacity consumers before failures happen. Therefore, the condition of the wheel-rail interface is important, since the state of the wheel influences that of the rail and vice versa. The monitoring of rail profiles is already being performed, but the monitoring of wheel profiles is still in the development phase. This thesis treats the applications and performance assessment of a wheel profile measurement system (WPMS), and presents case studies focusing on its system and measurement performance. The proposed applications concern how the information from the WPMS can be integrated with information from other data sources and with physical models to obtain a true current picture of the wheel behaviour. The thesis investigates the measurement performance of the WPMS by using a paired T-test and a number of quality measures, e.g. the reproducibility and repeatability, the precision-to-tolerance ratio and the signal-to-noise ratio. In conclusion, this thesis shows that the WPMS works well with an expected level of reliability in a harsh climate with respect to its measurement and system performance. By combining other data with the data from the WPMS, potentially abnormal wheels can be found in an early stage if the proposed new maintenance limit for the wheel parameter of the flange height is implemented. Furthermore, through adding a physical model to the process, the real contact condition of the actual wheel-rail interface can be evaluated and measurement deviations can be found. However, the wheel parameters, as well as the entire profile, need a high measurement quality with little variation, which seems to be an issue with respect to the measurement performance when advanced calculations are to be done. Therefore, a new approach for evaluating measurement performance has been developed using established statistical tools and quality measures with predefined acceptance limits; with the help of this approach, one can differentiate between the variation in the measurements originating in the different measurement units and the variation originating in the wheels. This new approach can be applied to judge the measurement performance of wheel profile condition-monitoring systems, and can also be implemented for other condition-monitoring systems to evaluate their measurement performance. Finally, this approach promotes the development of a condition-based maintenance policy by providing more reliable information for maintenance decision makers.
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| 30. |
- Atashipour, Seyed Rasoul
(författare)
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Structural Analysis of Deep Composite Box-Type Components with application to a proprietary stabilising timber wall element
- 2016
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The stabilising wall element of the Trä8-system is a deep box-type beam/column element which is made of different types of timber composites including framing members of gluedlaminated timber (glulam) and sheathings of laminated veneer lumber (LVL). This element is used as a ―shear wall‖ in multi-storey buildings up to four storeys. To be able to optimise thecomposite stabilising element and use its maximum potential and efficiency, it is necessary to have sufficient fundamental knowledge and information about the structural behaviour and influences of different mechanical properties and geometrical parameters and dimensions of the sub-elements.In this thesis, structural analysis and design principles of the Trä8 stabilising wall element are discussed, including the early stage of erection during assembly to the final usage and residence. A list of required fundamental basic analyses are presented, including accurate deflection analysis for the serviceability limit state, local pre- and post-buckling of the LVL sheathings, global buckling as well as the lateral-torsional buckling of the stabilising element in different design situations. This thesis is then focused on deformations and local instability. For each type of structural problem, accurate, but simple and general methodology is employed to incorporate a large number of effective geometric and property parameters. In this way, a fast evaluation of the influence of different parameters is possible for a wide range of values without needing several time-consuming 3-D finite element (FE) simulations. In several cases, the accuracy and validity of the obtained solutions and formulae are examined and confirmed by comparing their results to those based on the 3-D FE simulations. First, different composite beam theories including shear effects are employed for deflection analysis of the stabilising timber element. Next, an accurate energy-based methodology isdeveloped rendering an explicit formula that gives accurate predictions for the deflection of the stabilising element within a medium range of sheathing or web thicknesses and/or stiffnesses. For weak shear webs, however, this model is not sufficient. Therefore, another new model based on the partial composite interaction theory is developed for accurate deflection predictions of the element having weak shear webs. This model contains simple but accurate formulae for deflection analysis of any similar composite box-type of element with an arbitrary range of geometry and property parameters.Next, shear buckling of the rectangular LVL-panel between the framing members are analysed using differential quadrature (DQ) numerical technique as well as an explicit analytical solution and a formula is established for accurate and fast prediction of the shear pre-buckling of the LVL. This study is extended by considering the effect of each individual lamina of the LVL as well as general orthotropic material properties using a laminated theoryand the DQ solution approach. Further, the post-buckling of the LVL panel is studied based on a simple analytical method with rotating stress fields together with the accurate 3-D FE simulations. A simple formula is then proposed for accurate prediction of the shear post-buckling resistance of the LVL-panel in the stabilising element. As a result of the thesis concerning the two main focus areas, deformations and local instability, explicit analytical formulae are presented for the design of the box-type stabilisingelement with respect to deflections including shear effects in the serviceability limit state and with respect to local shear buckling of the sheathings of the stabilising element including the post-critical area in the ultimate limit state.
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