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During train operation, geometrical irregularities develop in soil-supported ballasted railway tracks as a function of born tonnage. This form of degradation is combatted by periodic maintenance in the form of tamping by specially equipped trains in order to guarantee predefined levels of structural performance. The growth of irregular settlements depends on one hand on track properties (such as sleeper spacing, rail bending stiffness, subsoil geotechnical properties) and the intensity of longitudinal stiffness variations (variations in soil profile, switches and crossings, transitions etc.). The latter stiffness variations include both the static and the dynamic, frequency-dependent stiffness. On the other hand also the nature of the loading has an important influence. Running trains exert – depending on their velocity – quasistatic loads on the infrastructure due to the passing axles with a constant loading. Apart from this a dynamic loading component may occur with different frequencies as a result of non-perfect wheels, as a function of the speed. In general, the structural design of a railway line can be optimised with respect to its structural performance for the whole lifecycle. However, for existing lines this is difficult, and the only way to limit degradation and associated costs is to influence the condition of the rolling stock. The present study discusses theoretical backgrounds of track degradation in the form of differential settlements. It then shows results of an analysis of the loading conditions on Dutch railway lines, with both mixed passenger and freight transport and with dedicated freight traffic, based on actual measurements. Conclusions are drawn regarding deterioration and the effects of different loading types. Results show that especially on freight lines huge improvements are possible, with reductions in geometrical degradation up to 52% of actual values. The main driver of excessive degradation appears to be the low-frequency dynamic ax

In the Netherlands research has been performed on the Observational Method, aiming at a wider use of the method in the design of underground and infrastructural construction works. This paper summarizes the guideline that was output of the research, providing a clear definition, an overview of obstacles and pre-conditions, practical recommendations on how to make a safe design while using the principles of Observational Method within the context of the Eurocode 7 and practical recommendations on how to organize the method during construction.

During train operation, geometrical irregularities develop in soil-supported ballasted railway tracks as a function of born tonnage. This form of degradation is combatted by periodic maintenance in the form of tamping by specially equipped trains in order to guarantee predefined levels of structural performance. The growth of irregular settlements depends on one hand on track properties (such as sleeper spacing, rail bending stiffness, subsoil geotechnical properties) and the intensity of longitudinal stiffness variations (variations in soil profile, switches and crossings, transitions etc.). The latter stiffness variations include both the static and the dynamic, frequency-dependent stiffness. On the other hand also the nature of the loading has an important influence. Running trains exert – depending on their velocity – quasistatic loads on the infrastructure due to the passing axles with a constant loading. Apart from this a dynamic loading component may occur with different frequencies as a result of non-perfect wheels, as a function of the speed. In general, the structural design of a railway line can be optimised with respect to its structural performance for the whole lifecycle. However, for existing lines this is difficult, and the only way to limit degradation and associated costs is to influence the condition of the rolling stock. The present study discusses theoretical backgrounds of track degradation in the form of differential settlements. It then shows results of an analysis of the loading conditions on Dutch railway lines, with both mixed passenger and freight transport and with dedicated freight traffic, based on actual measurements. Conclusions are drawn regarding deterioration and the effects of different loading types. Results show that especially on freight lines huge improvements are possible, with reductions in geometrical degradation up to 52% of actual values. The main driver of excessive degradation appears to be the low-frequency dynamic ax

In the Netherlands research has been performed on the Observational Method, aiming at a wider use of the method in the design of underground and infrastructural construction works. This paper summarizes the guideline that was output of the research, providing a clear definition, an overview of obstacles and pre-conditions, practical recommendations on how to make a safe design while using the principles of Observational Method within the context of the Eurocode 7 and practical recommendations on how to organize the method during construction.

During train operation, geometrical irregularities develop in soil-supported ballasted railway tracks as a function of born tonnage. This form of degradation is combatted by periodic maintenance in the form of tamping by specially equipped trains in order to guarantee predefined levels of structural performance. The growth of irregular settlements depends on one hand on track properties (such as sleeper spacing, rail bending stiffness, subsoil geotechnical properties) and the intensity of longitudinal stiffness variations (variations in soil profile, switches and crossings, transitions etc.). The latter stiffness variations include both the static and the dynamic, frequency-dependent stiffness. On the other hand also the nature of the loading has an important influence. Running trains exert – depending on their velocity – quasistatic loads on the infrastructure due to the passing axles with a constant loading. Apart from this a dynamic loading component may occur with different frequencies as a result of non-perfect wheels, as a function of the speed. In general, the structural design of a railway line can be optimised with respect to its structural performance for the whole lifecycle. However, for existing lines this is difficult, and the only way to limit degradation and associated costs is to influence the condition of the rolling stock. The present study discusses theoretical backgrounds of track degradation in the form of differential settlements. It then shows results of an analysis of the loading conditions on Dutch railway lines, with both mixed passenger and freight transport and with dedicated freight traffic, based on actual measurements. Conclusions are drawn regarding deterioration and the effects of different loading types. Results show that especially on freight lines huge improvements are possible, with reductions in geometrical degradation up to 52% of actual values. The main driver of excessive degradation appears to be the low-frequency dynamic ax, Structural Engineering, Civil Engineering and Geosciences

Solving today's complex hydrological problems requires originality, creative thinking and trans-disciplinary approaches. Hydrological education that was traditionally teacher centred, where the students look up to the teacher for expertise and information, should change to better prepare hydrologists to develop new knowledge and apply it in new contexts. An important first step towards this goal is to change the concept of education in the educators' minds. The results of an investigation to find out whether didactic training influences the beliefs of hydrology educators about their teaching styles is presented. Faculty of UNESCO-IHE has been offered a didactic certification program named university teaching qualification (UTQ). The hypothesis that UTQ training will significantly alter the teaching style of faculty at UNESCO-IHE from expert/formal authority traits towards facilitator/delegator traits was tested. A first survey was conducted among the entire teaching staff (total 101, response rate 58%). The results indicated that there are significantly higher traits of facilitator and delegator teaching styles among UTQ graduates compared to faculty who were not significantly trained in didactics. The second survey which was conducted among UTQ graduates (total 20, response rate 70%), enquiring after their teaching styles before and after UTQ, corroborated these findings., Water Management, Civil Engineering and Geosciences

Global environmental changes introduce new challenges and expose future university graduates in hydrology and related fields to problems of unprecedented complexity and magnitude. The T-shape model is proposed as a generic competency profile guiding the design of university curricula. This model differentiates between cognitive competencies in a certain field (i.e. hydrology; vertical leg of the T), and other cognitive/knowledge competencies in neighboring fields (e.g. hydraulics, aquatic ecology, land use management etc.) and functional, personal and values competencies and meta-competencies (all summarized in the horizontal bar of the T). It is based on the holistic model of professional competencies by Cheetham and Chivers (1996) and related studies (Oskam, 2009). The T-shape profile should apply to all levels of higher education (1st degree till doctorate level) in hydrology and related fields. For the effectiveness of hydrologists as professionals, a variable mix of competencies is required and further discussed. Key aspects are an open attitude for learning, continuous professional development (lifelong learning), and integrative and team working skills. Furthermore, a stimulating learning environment that promotes active learning is essential. As examples that substantiate the proposed T-shape model, the post-graduate education programmes of UNESCO-IHE and the main outcomes from a university curriculum workshop to promote education for sustainable development are introduced., Water Management, Civil Engineering and Geosciences

Solving today's complex hydrological problems requires originality, creative thinking and trans-disciplinary approaches. Hydrological education that was traditionally teacher centred, where the students look up to the teacher for expertise and information, should change to better prepare hydrologists to develop new knowledge and apply it in new contexts. An important first step towards this goal is to change the concept of education in the educators' minds. The results of an investigation to find out whether didactic training influences the beliefs of hydrology educators about their teaching styles is presented. Faculty of UNESCO-IHE has been offered a didactic certification program named university teaching qualification (UTQ). The hypothesis that UTQ training will significantly alter the teaching style of faculty at UNESCO-IHE from expert/formal authority traits towards facilitator/delegator traits was tested. A first survey was conducted among the entire teaching staff (total 101, response rate 58%). The results indicated that there are significantly higher traits of facilitator and delegator teaching styles among UTQ graduates compared to faculty who were not significantly trained in didactics. The second survey which was conducted among UTQ graduates (total 20, response rate 70%), enquiring after their teaching styles before and after UTQ, corroborated these findings., Water Management, Civil Engineering and Geosciences

Global environmental changes introduce new challenges and expose future university graduates in hydrology and related fields to problems of unprecedented complexity and magnitude. The T-shape model is proposed as a generic competency profile guiding the design of university curricula. This model differentiates between cognitive competencies in a certain field (i.e. hydrology; vertical leg of the T), and other cognitive/knowledge competencies in neighboring fields (e.g. hydraulics, aquatic ecology, land use management etc.) and functional, personal and values competencies and meta-competencies (all summarized in the horizontal bar of the T). It is based on the holistic model of professional competencies by Cheetham and Chivers (1996) and related studies (Oskam, 2009). The T-shape profile should apply to all levels of higher education (1st degree till doctorate level) in hydrology and related fields. For the effectiveness of hydrologists as professionals, a variable mix of competencies is required and further discussed. Key aspects are an open attitude for learning, continuous professional development (lifelong learning), and integrative and team working skills. Furthermore, a stimulating learning environment that promotes active learning is essential. As examples that substantiate the proposed T-shape model, the post-graduate education programmes of UNESCO-IHE and the main outcomes from a university curriculum workshop to promote education for sustainable development are introduced., Water Management, Civil Engineering and Geosciences

Het is haast onmogelijk om de werkzame jaren van Prof. Dr. Clemens Steenbergen hier op de TU Delft in het kort samen te vatten. Dit is een persoonlijk boek van collega's, medewerkers en studenten ter gelegenheid van zijn afscheid op 15. December 2011., Urbanism, Architecture

Het is haast onmogelijk om de werkzame jaren van Prof. Dr. Clemens Steenbergen hier op de TU Delft in het kort samen te vatten. Dit is een persoonlijk boek van collega's, medewerkers en studenten ter gelegenheid van zijn afscheid op 15. December 2011., Urbanism, Architecture

Outfalls are built for the purpose ofdischarging sewage, storm runoff or cooling water into the sea. During the installation, outfalls are exposed to relatively large hydrodynamic forces compared to their own weight in case of adverse weather or high currents. To resist these forces, a heavy concrete weight coating has to be applied. With increasingly stringent environmental directives, it is important to situate the end of an outfall further offshore. This is possible by optimising the conservative schematisation of the offshore technology common practice of pipeline stability applied to outfalls. This optimisation can lead to a reduction of the outfall weight coating, which offers perspectives to the construction of longer outfalls and an improved economic design in general. Therefor, research into a less conservative approach of calculating the resultant hydrodynamic forces on outfalls has been carried out as a graduate project at Delft University of Technology. The graduate project concentrates on the most common situation of an outfall built in shallow water, approximately at right angles to the depth contours. Trenching and application of a heavy weight coating have to assure stability during installation. The impact forces on the outfall generated by breaking waves will not be considered., Hydraulic Engineering, Civil Engineering and Geosciences

Outfalls are built for the purpose ofdischarging sewage, storm runoff or cooling water into the sea. During the installation, outfalls are exposed to relatively large hydrodynamic forces compared to their own weight in case of adverse weather or high currents. To resist these forces, a heavy concrete weight coating has to be applied. With increasingly stringent environmental directives, it is important to situate the end of an outfall further offshore. This is possible by optimising the conservative schematisation of the offshore technology common practice of pipeline stability applied to outfalls. This optimisation can lead to a reduction of the outfall weight coating, which offers perspectives to the construction of longer outfalls and an improved economic design in general. Therefor, research into a less conservative approach of calculating the resultant hydrodynamic forces on outfalls has been carried out as a graduate project at Delft University of Technology. The graduate project concentrates on the most common situation of an outfall built in shallow water, approximately at right angles to the depth contours. Trenching and application of a heavy weight coating have to assure stability during installation. The impact forces on the outfall generated by breaking waves will not be considered., Hydraulic Engineering, Civil Engineering and Geosciences

Het ontwerpen en beproeven van een demonstratiepaneel met bijbehorende besturingslogika voor een drietraps schalmnetwerk; het ontwerp dient geschikt te zijn voor visuele ondersteuning van het kollege "Automatische Telefonie"., Electrical Engineering, Mathematics and Computer Science, Laboratorium voor Automatische Verkeerssystemen