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Engineers assessing and strengthening the structural safety of 19th-century wrought-iron riveted connections need information on the materials applied, the riveting technology and the impact of remedial works. However, the structural impact of actual remedial works on wrought-iron riveted connections remains little known to this day. Therefore, a lap shear test campaign on single riveted single lap joints made of wrought iron was carried out. Both original and repaired riveted lap joints were designed, fabricated and tested. This paper reports on the ultimate shear behaviour of wrought-iron riveted connections and covers the effect of the quality of riveting. The shear tests showed that original riveted specimens failed in tension (plate net section failure). The repair intervention involving modern steel materials and techniques improved the ultimate shear behaviour significantly.

Rijkswaterstaat bestort de vooroevers voor de dijken in de Ooster- en Westerschelde om de waterveiligheid te kunnen blijven waarborgen. Voor deze bestortingen wordt gebruik gemaakt van staalslakken, breukstenen en zeegrind. Om de gevolgen van het bestorten voor het plaatselijke onderwaterleven inzichtelijk te maken wordt monitoring uitgevoerd door IMARES in opdracht van Rijkswaterstaat. Hierbij wordt onderzoek gedaan naar hard substraat soorten (planten en dieren gevestigd op de harde oever), zacht substraat soorten (dieren die in het sediment op de vooroever leven) en mogelijke uitloging van zware metalen vanuit de vooroeverbestorting naar planten en dieren

Rijkswaterstaat bestort de vooroevers voor de dijken in de Ooster- en Westerschelde om de waterveiligheid te kunnen blijven waarborgen. Voor deze bestortingen wordt gebruik gemaakt van staalslakken, breukstenen en zeegrind. Om de gevolgen van het bestorten voor het plaatselijke onderwaterleven inzichtelijk te maken wordt monitoring uitgevoerd door IMARES in opdracht van Rijkswaterstaat. Hierbij wordt onderzoek gedaan naar hard substraat soorten (planten en dieren gevestigd op de harde oever), zacht substraat soorten (dieren die in het sediment op de vooroever leven) en mogelijke uitloging van zware metalen vanuit de vooroeverbestorting naar planten en dieren

Metalen verpakkingen en huishoudmagnetrons lijken niet samen te gaan. Uit onderzoek door onder meer ATO blijkt dat ultradunne stalen verpakkingen wel geschikt zijn voor magnetrongebruik en zelfs voordelen bieden

Harbour infrastructures, civil engineering structures and offshore structures are exposed to a very aggressive maritime environment. The local corrosion mechanism bio-corrosion or microbial influenced corrosion (MIC) seems to be the life determining failure mechanism for these structures. There is a need for durable solutions to protect and maintain these structures. Different corrosion protection methods and systems are commercially available but each application requires a specific protection system. The optimal solution is not available yet

Harbour infrastructures, civil engineering structures and offshore structures are exposed to a very aggressive maritime environment. The local corrosion mechanism bio-corrosion or microbial influenced corrosion (MIC) seems to be the life determining failure mechanism for these structures. There is a need for durable solutions to protect and maintain these structures. Different corrosion protection methods and systems are commercially available but each application requires a specific protection system. The optimal solution is not available yet

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Teneinde de milieubelasting als gevolg van economische activiteiten te prognotiseren worden economische scenario's van het Centraal Planbureau (CPB) getransformeerd naar fysieke scenario's. Door koppeling van emissie- en energiefactoren aan de geprognotiseerde fysieke productie kunnen de te verwachten emissies en het energieverbruik worden berekend. Het CPB en het RIVM ontwikkelen gezamenlijk een model waarmee de economische scenario's beter dan met het voorgaande model 'TRAFO' kunnen worden omgerekend tot fysieke scenario's. Bij de ontwikkeling van STREAM (acroniem voor: Substance Throughput Relating to Economic Activity Model) is het RIVM verantwoordelijk voor de invulling van de aspecten 'hergebruik, substitutie en technologische ontwikkeling'. STREAM bestaat uit meerdere op de verwerking van grondstoffen georienteerde submodellen. Centraal in het onderzoek staat de vraag hoe hergebruik van ijzer en staal kan worden gemodelleerd. De inzet van ijzer- en staalschroot in het dominante staalproductieproces (oxystaalproces) kan afhankelijk worden gesteld van de productenpakket-samenstelling. Het blijkt dat bij de productie van lange producten (buizen, stalen profielen) relatief meer schroot wordt ingezet dan bij de productie van platte producten (blik, plaatstaal). De productenpakket-samenstelling kan vervolgens verklaard worden door de finale consumptie ten opzichte van het bruto binnenlands product. In de Nederlandse situatie is geen significante relatie aan te tonen tussen de inzet van ijzer- en staalschroot en de productenpakket-samenstelling. Voor Nederland is voor de vergelijking die de relatie schrootinzet ten opzichte van de totale productie beschrijft, gebruik gemaakt van een trendanalyse.

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Teneinde de milieubelasting als gevolg van economische activiteiten te prognotiseren worden economische scenario's van het Centraal Planbureau (CPB) getransformeerd naar fysieke scenario's. Door koppeling van emissie- en energiefactoren aan de geprognotiseerde fysieke productie kunnen de te verwachten emissies en het energieverbruik worden berekend. Het CPB en het RIVM ontwikkelen gezamenlijk een model waarmee de economische scenario's beter dan met het voorgaande model 'TRAFO' kunnen worden omgerekend tot fysieke scenario's. Bij de ontwikkeling van STREAM (acroniem voor: Substance Throughput Relating to Economic Activity Model) is het RIVM verantwoordelijk voor de invulling van de aspecten 'hergebruik, substitutie en technologische ontwikkeling'. STREAM bestaat uit meerdere op de verwerking van grondstoffen georienteerde submodellen. Centraal in het onderzoek staat de vraag hoe hergebruik van ijzer en staal kan worden gemodelleerd. De inzet van ijzer- en staalschroot in het dominante staalproductieproces (oxystaalproces) kan afhankelijk worden gesteld van de productenpakket-samenstelling. Het blijkt dat bij de productie van lange producten (buizen, stalen profielen) relatief meer schroot wordt ingezet dan bij de productie van platte producten (blik, plaatstaal). De productenpakket-samenstelling kan vervolgens verklaard worden door de finale consumptie ten opzichte van het bruto binnenlands product. In de Nederlandse situatie is geen significante relatie aan te tonen tussen de inzet van ijzer- en staalschroot en de productenpakket-samenstelling. Voor Nederland is voor de vergelijking die de relatie schrootinzet ten opzichte van de totale productie beschrijft, gebruik gemaakt van een trendanalyse.

Handleiding voor de CE-markering van staalconstructies onder de Bouwproductenrichtlijn en EN 1090

De nieuwe bijage 6 is van toepassing vanaf 15/08/2009. Deze nieuwe bijlage, van toepassing voor industriegebouwen, luidt fire safety engineering in binnen de bouwsector. Dit betekent een evolutie van de prescriptieve regels naar op performantie-criteria gebaseerde ontwerp. Achtergrond, begrippen en voorbeelden aangaande de beoordeling van het structureel gedrag van industriële gebouwen bij brand worden toegelicht. ispartof: Studie-avond Brand Bijlage 6 date:7 Jan - 7 Jan 2009 status: published

Het Koninklijk Domein van Laken, gelegen ten noorden van Brussel, is één van de residenties van de Belgische Koninklijke familie. Het paleis werd in 1781 gebouwd onder impuls van de gouverneurs-generaal van de Oostenrijkse Nederlanden. Het werd uitgebreid met een oranjerie in 1818 en een serrecomplex tussen 1874 en 1905. Het uitgestrekte park bevat één van de meesterstukken uit de Belgische negentiende-eeuwse ijzer- en glasarchitectuur: te midden van het complex van serres staat de Wintertuin, die door hofarchitect Alphonse Balat in opdracht van koning Leopold II gebouwd werd in 1874-1876. Dit artikel beschrijft de bouw van deze Wintertuin.

From 1860 until 1920, the evolutions in architecture were enormous. The Art Nouveau movement was born at the end of the nineteenth century and is internationally known as the highlight of the cultural history of Belgium. However, the scientific research of this important period mostly ignores the construction and engineering technology. The publication focuses on the goals of a research project on glass coverings that started at the Vrije Universiteit Brussels.

IJzer en staal worden reeds meerdere eeuwen gebruikt in de bouwwereld. De terminologie, die naar de historische metalen en de bijhorende eigenschappen verwijst, is zeer onduidelijk en verwarrend. In het kader van hedendaagse renovatieprojecten is het echter belangrijk om de evolutie, het onderscheid en de eigenschappen van deze metalen grondig te kennen. Aan de hand van drie schema's betreffende de productie, de kwaliteit en de vorm tracht dit artikel de situatie te verduidelijken voor de ijzer- en staalsoorten die voor structurele doeleinden ingezet werden tussen 1860 en 1914.

Industrial activities cause a variety of environmental problems. These are largely caused by emissions of air pollutants, the production of waste and depletion of natural resources. As a consequence, industrial managers face a complex problem when assessing the overall environmental pressure on the environment, and options to reduce this pressure. This complexity is associated with the range of activities taking place in industrial processes, the variety and complexity of their environmental effects, the number of available technologies for pollution control, and the costs of pollution reduction. Despite this complexity, pollution reduction in industry is not always based on systematic analyses,noron clearly defined company priorities to environmental management. An important reason for this is a lack of integrated analyses of the environmental impact of industrial processes, the options to reduce this impact and the associated costs. An instrument to assist plant managers in deciding on environmental management is of utmost importance. However, a decision support tool that takes a company perspective and covers all relevant environmental issues as well as costs of environmental management is currently not available in the literature.The overall objective of the thesis is to develop a decision support tool to analyse options to reduce the environmental impact of an industrial company. A model is developed for the assessment of the potential environmental impact resulting from emissions of environmental pollutants, as well as the effectiveness of reduction options and the associated costs. The tool aims to take a company perspective and to assist the company management in the analyses of possible strategies to improve the company's environmental performance. An industrial plant, supplying the automotive industry with aluminium pressure die casting products, located inPortugal, served as case study.The following research questions are addressed:1)What existing environmental systems analysis methods and tools can in principle be combined in a decision support tool and used to analyse the environmental performance of a plant from a company perspective?Which technical pollution reduction options are available for reducing the environmental impact of an aluminium pressure die casting plant? What are their technical potentials to reduce this impact, and the associated costs for the plant?How can a model be developed that can be used from a company perspective to analyse options to reduce the environmental impact of aluminium pressure die casting?How do different strategies to combine pollution reduction options improve the environmental performance of an aluminium pressure die casting plant, and what are the associated costs for the plant?Environmental systems analysis (ESA) is often used to assist decision making in finding solution to complex environmental problems. A systems analysis research strategy is followed to address the above formulated research questions. It is based on a stepwise approach consisting of: 1) Problem definition; 2) Evaluation and selection of existing ESA tools; 3) Identification of pollution reduction options; 4) Model building; 5) Model application and finally 6) Evaluation of the methodological approach.In this environmental systems analysis, seven analytical tools are combined. These are selected on the basis of criteria ensuring an analysis that takes a company perspective; includes environmental and economic aspects of decision making; includes a complete coverage of the potential environmental impacts and allows for an assessment of the consequences of pollution reduction strategies. The associated characteristics of the decision support tool to be developed are that it i) considers a gate-to-gate approach; ii) considers the processes within the plant that are relevant for the assessment of the environmental impact; iii) uses plant specific data easily available from the process owner; iv) considers up-to-date and plant specific pollution reduction options; v) provides information on the cost-effectiveness of the reduction options; vi) can be used to express the environmental performance in one overall environmentalindicator; and vii) can be used to explore possible user-defined pollution reduction strategies. Based on these characteristics the following analytical tools are considered useful for the purpose of this study: Life Cycle Assessment, Substance Flow Analysis, Multi-Criteria Analysis, Technology Assessment, Sensitivity Analysis, Scenario Analysis and Cost-Effectiveness Analysis.Next, 18 pollution reduction options are identified for the aluminium pressure die casting plant studied. For each option the potential to reduce the pollution and the costs associated with their implementation is estimated. The options include typical end-of-pipe solutions, as well as more structural changes in the industrial processes. The options are considered the best available for the current aluminium pressure die casting sector. The inventory shows that promising and effective opportunities exist for pollution reduction.A model (MIKADO) is developed for and applied to the specific aluminium die casting plant. MIKADO is the Model of the environmental Impact of an Aluminium Die casting plant and Options to reduce this impact . The model includes material and energy flows in the plant that give rise to environmental problems. It considers the following sub-processes: Melting; Casting; Finishing; Internal Transports and Auxiliary Burners. MIKADO can be used to analyse future trends in the potential environmental impact of the aluminium pressure die casting plant and the effect of different pollution reduction strategies, as well as the costs for the company. One of the strengths of MIKADO is the integrated approach that it takes in analysing, simultaneously, all the relevant environmental problems caused by the aluminium die casting plant.MIKADO results are first analysed for the situation that reflects the current practice in the plant. In addition, a partial sensitivity analysis performed to study the sensitivity of MIKADO results to changes in parameter values. The results indicate that more than 90% of the environmental impact of the company is from the sub-processes Melting and Casting. Moreover, the environmental impact caused by the plant is mostly associated with human toxicity problems (caused by metal emissions, and emissions of ozone precursors) and the depletion of natural gas. Four relatively larger sources of environmental pollution include the use of natural gas and emissions of hydrogen fluoride in Melting, and emission of chromium and non-methane volatile organic compounds from Casting. These four cause about two-thirds of the overall environmental impact. MIKADO results show to be relatively insensitive to the valuation factors used to assess the overall environmental impact.A systematic analysis of the pollution reduction options reveals that the potential to reduce pollution varies largely for the 18 options analysed. Individual options may reduce the overall environmental impact by up to 40%. The most effective single options, leading to the largest reductions, are found to be two wet scrubbers associated to Casting. The costs to implement reduction options differ largely. Six options have net negative costs, implying that the company may in fact earn money by implementing them. These include the use of a granular desoxidation agent, reduction of the scrap produced during Casting and Finishing, the use of electric forklift trucks in internal transport, a new mould release agent and compacting the metal load entering the melting furnaces. The last option is found to be the most paying.Seven different types of reduction strategies are analysed, assuming the simultaneous implementation of different pollution reduction options. These strategies, reflecting different environmental management objectives, are analysed with respect to their potential to reduce the environmental impact and the costs associated with the implementation of options. The strategies differ largely with respect to their effect on the environmental impact (10 - 87% reduction) and costs (-268 to + 277 kEuro/year). The most effective strategy is a combination of options to reduce human toxicity, but this is also a relatively costly strategy. The least effective is related to metal yield increase. Combining the most paying options is an interesting strategy: it reduces the overall environmental impact by 45% at negative net costs (-268 kEuro/year). Eleven strategies could be defined which reduce the overall environmental impact by more than 50%. Of these two have net negative costs. It is also possible to reduce largely the environmental impact in the case in which the costs of add-on techniques are compensated by benefits of the paying options. This is, for instance, the case when most cost effective options are combined. Results show a large reduction in the overall environmental impact (86% reduction), while the company gains 51 kEuro/year.Novel aspects of this thesis include: 1) the company perspective that it takes; 2) the involvement of plant managers throughout the research; 3) the environmental systems analysis research strategy (sequence of environmental systems analysis steps and iterations), and 4) the selection of environmental systems analyses tools.The company perspective taken when developing MIKADO is reflected by the definition of system boundaries, the production processes included and the pollution reduction options considered in the model characteristics. The decision support tool only considers the industrial processes that can be managed by the plant managers, as well as the different types of environmental problems that the plant contributes to (air emissions, liquid effluents, solid wastes and natural resources used within the plant gates).The involvement of plant managers during MIKADO development was essential for ensuring that the tool to support decision making fulfils their expectations on the assessment of the environmental performance of the plant. A major strength of the tool developed to plant managers is its flexibility. This flexibility contributes to the willingness of the plant manager to use MIKADO to analyse possibilities for environmental management in the plant.The research strategy taken in this thesis includes a unique sequence of steps and iterations and is considered the appropriate and useful for development of decision support tools for environmental management in industrial companies. The environmental systems analysis procedure followed here may also be useful in assisting environmental decision making by other industries.Finally, the procedure to select analytical tools as a basis for the model was helpful. The detailed description of the procedure followed and the resulting combination of the analytical tools may serve as an example for other studies. This also holds for the combination of seven different environmental systems analysis tools, as presented in this thesis.

Industrial activities cause a variety of environmental problems. These are largely caused by emissions of air pollutants, the production of waste and depletion of natural resources. As a consequence, industrial managers face a complex problem when assessing the overall environmental pressure on the environment, and options to reduce this pressure. This complexity is associated with the range of activities taking place in industrial processes, the variety and complexity of their environmental effects, the number of available technologies for pollution control, and the costs of pollution reduction. Despite this complexity, pollution reduction in industry is not always based on systematic analyses,noron clearly defined company priorities to environmental management. An important reason for this is a lack of integrated analyses of the environmental impact of industrial processes, the options to reduce this impact and the associated costs. An instrument to assist plant managers in deciding on environmental management is of utmost importance. However, a decision support tool that takes a company perspective and covers all relevant environmental issues as well as costs of environmental management is currently not available in the literature.The overall objective of the thesis is to develop a decision support tool to analyse options to reduce the environmental impact of an industrial company. A model is developed for the assessment of the potential environmental impact resulting from emissions of environmental pollutants, as well as the effectiveness of reduction options and the associated costs. The tool aims to take a company perspective and to assist the company management in the analyses of possible strategies to improve the company's environmental performance. An industrial plant, supplying the automotive industry with aluminium pressure die casting products, located inPortugal, served as case study.The following research questions are addressed:1)What existing environmental systems analysis methods and tools can in principle be combined in a decision support tool and used to analyse the environmental performance of a plant from a company perspective?Which technical pollution reduction options are available for reducing the environmental impact of an aluminium pressure die casting plant? What are their technical potentials to reduce this impact, and the associated costs for the plant?How can a model be developed that can be used from a company perspective to analyse options to reduce the environmental impact of aluminium pressure die casting?How do different strategies to combine pollution reduction options improve the environmental performance of an aluminium pressure die casting plant, and what are the associated costs for the plant?Environmental systems analysis (ESA) is often used to assist decision making in finding solution to complex environmental problems. A systems analysis research strategy is followed to address the above formulated research questions. It is based on a stepwise approach consisting of: 1) Problem definition; 2) Evaluation and selection of existing ESA tools; 3) Identification of pollution reduction options; 4) Model building; 5) Model application and finally 6) Evaluation of the methodological approach.In this environmental systems analysis, seven analytical tools are combined. These are selected on the basis of criteria ensuring an analysis that takes a company perspective; includes environmental and economic aspects of decision making; includes a complete coverage of the potential environmental impacts and allows for an assessment of the consequences of pollution reduction strategies. The associated characteristics of the decision support tool to be developed are that it i) considers a gate-to-gate approach; ii) considers the processes within the plant that are relevant for the assessment of the environmental impact; iii) uses plant specific data easily available from the process owner; iv) considers up-to-date and plant specific pollution reduction options; v) provides information on the cost-effectiveness of the reduction options; vi) can be used to express the environmental performance in one overall environmentalindicator; and vii) can be used to explore possible user-defined pollution reduction strategies. Based on these characteristics the following analytical tools are considered useful for the purpose of this study: Life Cycle Assessment, Substance Flow Analysis, Multi-Criteria Analysis, Technology Assessment, Sensitivity Analysis, Scenario Analysis and Cost-Effectiveness Analysis.Next, 18 pollution reduction options are identified for the aluminium pressure die casting plant studied. For each option the potential to reduce the pollution and the costs associated with their implementation is estimated. The options include typical end-of-pipe solutions, as well as more structural changes in the industrial processes. The options are considered the best available for the current aluminium pressure die casting sector. The inventory shows that promising and effective opportunities exist for pollution reduction.A model (MIKADO) is developed for and applied to the specific aluminium die casting plant. MIKADO is the Model of the environmental Impact of an Aluminium Die casting plant and Options to reduce this impact . The model includes material and energy flows in the plant that give rise to environmental problems. It considers the following sub-processes: Melting; Casting; Finishing; Internal Transports and Auxiliary Burners. MIKADO can be used to analyse future trends in the potential environmental impact of the aluminium pressure die casting plant and the effect of different pollution reduction strategies, as well as the costs for the company. One of the strengths of MIKADO is the integrated approach that it takes in analysing, simultaneously, all the relevant environmental problems caused by the aluminium die casting plant.MIKADO results are first analysed for the situation that reflects the current practice in the plant. In addition, a partial sensitivity analysis performed to study the sensitivity of MIKADO results to changes in parameter values. The results indicate that more than 90% of the environmental impact of the company is from the sub-processes Melting and Casting. Moreover, the environmental impact caused by the plant is mostly associated with human toxicity problems (caused by metal emissions, and emissions of ozone precursors) and the depletion of natural gas. Four relatively larger sources of environmental pollution include the use of natural gas and emissions of hydrogen fluoride in Melting, and emission of chromium and non-methane volatile organic compounds from Casting. These four cause about two-thirds of the overall environmental impact. MIKADO results show to be relatively insensitive to the valuation factors used to assess the overall environmental impact.A systematic analysis of the pollution reduction options reveals that the potential to reduce pollution varies largely for the 18 options analysed. Individual options may reduce the overall environmental impact by up to 40%. The most effective single options, leading to the largest reductions, are found to be two wet scrubbers associated to Casting. The costs to implement reduction options differ largely. Six options have net negative costs, implying that the company may in fact earn money by implementing them. These include the use of a granular desoxidation agent, reduction of the scrap produced during Casting and Finishing, the use of electric forklift trucks in internal transport, a new mould release agent and compacting the metal load entering the melting furnaces. The last option is found to be the most paying.Seven different types of reduction strategies are analysed, assuming the simultaneous implementation of different pollution reduction options. These strategies, reflecting different environmental management objectives, are analysed with respect to their potential to reduce the environmental impact and the costs associated with the implementation of options. The strategies differ largely with respect to their effect on the environmental impact (10 - 87% reduction) and costs (-268 to + 277 kEuro/year). The most effective strategy is a combination of options to reduce human toxicity, but this is also a relatively costly strategy. The least effective is related to metal yield increase. Combining the most paying options is an interesting strategy: it reduces the overall environmental impact by 45% at negative net costs (-268 kEuro/year). Eleven strategies could be defined which reduce the overall environmental impact by more than 50%. Of these two have net negative costs. It is also possible to reduce largely the environmental impact in the case in which the costs of add-on techniques are compensated by benefits of the paying options. This is, for instance, the case when most cost effective options are combined. Results show a large reduction in the overall environmental impact (86% reduction), while the company gains 51 kEuro/year.Novel aspects of this thesis include: 1) the company perspective that it takes; 2) the involvement of plant managers throughout the research; 3) the environmental systems analysis research strategy (sequence of environmental systems analysis steps and iterations), and 4) the selection of environmental systems analyses tools.The company perspective taken when developing MIKADO is reflected by the definition of system boundaries, the production processes included and the pollution reduction options considered in the model characteristics. The decision support tool only considers the industrial processes that can be managed by the plant managers, as well as the different types of environmental problems that the plant contributes to (air emissions, liquid effluents, solid wastes and natural resources used within the plant gates).The involvement of plant managers during MIKADO development was essential for ensuring that the tool to support decision making fulfils their expectations on the assessment of the environmental performance of the plant. A major strength of the tool developed to plant managers is its flexibility. This flexibility contributes to the willingness of the plant manager to use MIKADO to analyse possibilities for environmental management in the plant.The research strategy taken in this thesis includes a unique sequence of steps and iterations and is considered the appropriate and useful for development of decision support tools for environmental management in industrial companies. The environmental systems analysis procedure followed here may also be useful in assisting environmental decision making by other industries.Finally, the procedure to select analytical tools as a basis for the model was helpful. The detailed description of the procedure followed and the resulting combination of the analytical tools may serve as an example for other studies. This also holds for the combination of seven different environmental systems analysis tools, as presented in this thesis.

New vision on flexural-torsional buckling Stability and strength of structural members Summary This thesis presents insight into the stability check of beam-columns loaded in compression and bending in a number of clearly distinct steps. Of decisive importance is the newly introduced symbol n* that is defined as: n* is the ratio of total deformation and 2snd order part of deformation Very important is the 'alerting function' that this symbol can fulfil when judging the stability of beamcolumns. In an iteration procedure a general formula is presented, in which all necessary data concerning bar properties and load case are covered. The safety is evaluated by checking if the requirements are met with help of a unity check. Also is described how to calculate the displacement. New result of this thesis is that a unified methodology for flexural-torsional buckling is applicable for all existing construction materials in structural engineering. Essentially the calculations can be done in a short time using a pocket calculator, without the use of other utilities. It has been deliberately chosen not to elaborate the derived formulas too far, in order to preserve a clear view on the cohesion and procedure.

New vision on flexural-torsional buckling Stability and strength of structural members Summary This thesis presents insight into the stability check of beam-columns loaded in compression and bending in a number of clearly distinct steps. Of decisive importance is the newly introduced symbol n* that is defined as: n* is the ratio of total deformation and 2snd order part of deformation Very important is the 'alerting function' that this symbol can fulfil when judging the stability of beamcolumns. In an iteration procedure a general formula is presented, in which all necessary data concerning bar properties and load case are covered. The safety is evaluated by checking if the requirements are met with help of a unity check. Also is described how to calculate the displacement. New result of this thesis is that a unified methodology for flexural-torsional buckling is applicable for all existing construction materials in structural engineering. Essentially the calculations can be done in a short time using a pocket calculator, without the use of other utilities. It has been deliberately chosen not to elaborate the derived formulas too far, in order to preserve a clear view on the cohesion and procedure.

Metalen verpakkingen en huishoudmagnetrons lijken niet samen te gaan. Uit onderzoek door onder meer ATO blijkt dat ultradunne stalen verpakkingen wel geschikt zijn voor magnetrongebruik en zelfs voordelen bieden

Scaffold erection work is physically demanding. This manual presents ways to make the work safer, based largely on ideas from worker. Using the methods decribed here, pilot projects were conducted in two scaffolding firms in the Netherlands. The two companies each completed six steps: (1) Organize the program; (2) Have workers list strain-and-strain hazards; (3) Get ideas and choose some solutions; (4) Test some solutions; (5) Implement the best solutions; (6) Evaluate the program. The main hazards turned out to be related to lifting, lowering, and otherwise moving materials. For all hazards, potential solutions were generated in special brainstorming sessions. Proposed solutions were inplemented in a trial. The evaluation found that several solutions are easy to implement and help reduce the physical workload. Almost all of the participating scaffold erectors said they preferred to work with the developed solutions. Management at both firms found the participatory ergonomics a positive experience and said this approach can be applied easily in other companies.

Scaffold erection work is physically demanding. This manual presents ways to make the work safer, based largely on ideas from worker. Using the methods decribed here, pilot projects were conducted in two scaffolding firms in the Netherlands. The two companies each completed six steps: (1) Organize the program; (2) Have workers list strain-and-strain hazards; (3) Get ideas and choose some solutions; (4) Test some solutions; (5) Implement the best solutions; (6) Evaluate the program. The main hazards turned out to be related to lifting, lowering, and otherwise moving materials. For all hazards, potential solutions were generated in special brainstorming sessions. Proposed solutions were inplemented in a trial. The evaluation found that several solutions are easy to implement and help reduce the physical workload. Almost all of the participating scaffold erectors said they preferred to work with the developed solutions. Management at both firms found the participatory ergonomics a positive experience and said this approach can be applied easily in other companies.

Vrouwen die een technisch beroep uitoefenen, blijken nogal eens problemen te ondervinden. In deze dissertatie wordt nagegaan wat er in arbeidsinhoud, arbeidsomstandigheden en arbeidsorganisaties zou moeten veranderen om de uitstroom van vrouwen in technische beroepen te voorkomen. Het onderzoek heeft betrekking de op bouw, de staalindustrie en de metaalproductenindustrie. De vijfenvijftig ondervraagde vrouwen hebben een opleiding op lbo- of mbo-niveau genoten. In elk der onderscheiden sectoren veroorzaken de arbeidsomstandigheden voor vrouwen risico's voor de gezondheid van nek, rug, schouders en ledematen. Dit ondanks het feit dat de vrouwen bepaalde taken niet mogen uitvoeren, omdat zij fysiek te belastend zijn. Ook uitsluiting van opdrachten die 'technisch te geavanceerd' worden bevonden, leiden enerzijds tot beperking van de (doorgroei)mogelijkheden en bevorderen anderzijds de uitzonderingspositie van vrouwen. Het overheidsbeleid gericht op vergroting van de participatie van vrouwen in technische beroepen zou meer aandacht moeten schenken aan de bedrijfsinterne processen, waarbij de kwaliteit van arbeid een rol speelt.

Vrouwen die een technisch beroep uitoefenen, blijken nogal eens problemen te ondervinden. In deze dissertatie wordt nagegaan wat er in arbeidsinhoud, arbeidsomstandigheden en arbeidsorganisaties zou moeten veranderen om de uitstroom van vrouwen in technische beroepen te voorkomen. Het onderzoek heeft betrekking de op bouw, de staalindustrie en de metaalproductenindustrie. De vijfenvijftig ondervraagde vrouwen hebben een opleiding op lbo- of mbo-niveau genoten. In elk der onderscheiden sectoren veroorzaken de arbeidsomstandigheden voor vrouwen risico's voor de gezondheid van nek, rug, schouders en ledematen. Dit ondanks het feit dat de vrouwen bepaalde taken niet mogen uitvoeren, omdat zij fysiek te belastend zijn. Ook uitsluiting van opdrachten die 'technisch te geavanceerd' worden bevonden, leiden enerzijds tot beperking van de (doorgroei)mogelijkheden en bevorderen anderzijds de uitzonderingspositie van vrouwen. Het overheidsbeleid gericht op vergroting van de participatie van vrouwen in technische beroepen zou meer aandacht moeten schenken aan de bedrijfsinterne processen, waarbij de kwaliteit van arbeid een rol speelt.

To determine priorities for ergonomic improvements in five maintenance departments of a steel company, a study was carried out to identify groups with a high prevalence of musculoskeletal problems or a high exposure to unfavourable musculoskeletal workload. All workers were asked to complete a standardized questionnaire on musculoskeletal symptoms and musculoskeletal workload. Response rate in the five departments varied between 60 and 80% (n = 436). Symptoms of low back and neck-shoulder (12-month prevalence rates of 53% and 36%, respectively) were most common, but not higher in comparison with a reference group of 396 non-sedentary workers. Self-reported exposure rates to physical and psychosocial loads as well as poor climatic conditions were comparable with the reference group; only exposure to vibration was higher. Significant differences were seen between the five departments as well as between task groups with the departments. Several task groups with relatively high symptom rates and high exposure levels could be identified. It is concluded that a questionnaire survey can constitute a valuable contribution to the selection of high-risk task groups that need ergonomic intervention. Chemicals/CAS: Steel, 12597-69-2

To determine priorities for ergonomic improvements in five maintenance departments of a steel company, a study was carried out to identify groups with a high prevalence of musculoskeletal problems or a high exposure to unfavourable musculoskeletal workload. All workers were asked to complete a standardized questionnaire on musculoskeletal symptoms and musculoskeletal workload. Response rate in the five departments varied between 60 and 80% (n = 436). Symptoms of low back and neck-shoulder (12-month prevalence rates of 53% and 36%, respectively) were most common, but not higher in comparison with a reference group of 396 non-sedentary workers. Self-reported exposure rates to physical and psychosocial loads as well as poor climatic conditions were comparable with the reference group; only exposure to vibration was higher. Significant differences were seen between the five departments as well as between task groups with the departments. Several task groups with relatively high symptom rates and high exposure levels could be identified. It is concluded that a questionnaire survey can constitute a valuable contribution to the selection of high-risk task groups that need ergonomic intervention. Chemicals/CAS: Steel, 12597-69-2

Working conditions, environmental protection and quality control are increasingly important for organizations. Most companies are being confronted with sharply increasing requirements in all three areas. It is up to the managers and the respective experts to determine the most desirable strategies for meeting these new requirements. This thesis describes the first systematic research on the joint management of these three aspects. It proves that it is vital for modern management to create and use the opportunities for synergy between the three areas and to achieve greater effectivity while simultaneously reducing costs. The thesis includes case studies in steel wire, trucks, paint, plastic and rubber industries.

Working conditions, environmental protection and quality control are increasingly important for organizations. Most companies are being confronted with sharply increasing requirements in all three areas. It is up to the managers and the respective experts to determine the most desirable strategies for meeting these new requirements. This thesis describes the first systematic research on the joint management of these three aspects. It proves that it is vital for modern management to create and use the opportunities for synergy between the three areas and to achieve greater effectivity while simultaneously reducing costs. The thesis includes case studies in steel wire, trucks, paint, plastic and rubber industries.