van Lankveld G.,Technical University of Delft |
van Lankveld G.,Open University in the Netherlands |
Sehic E.,ProRail |
Lo J.C.,Technical University of Delft |
And 2 more authors.
Simulation and Gaming | Year: 2017
Background. The Dutch railway company ProRail is performing large-scale capacity upgrades to their infrastructure network. As part of these upgrades, ProRail uses gaming simulations to help prepare train traffic controllers for new infrastructure situations. Researching the validity of these gaming simulations is essential, since the conclusions drawn from gaming simulation use may result in decisions with large financial and social impact for ProRail and Dutch train passengers. Aim. In this article, we aim to investigate the validity of the gaming simulations for training traffic controllers for new situations in rail infrastructure. We also aim to contribute to the discussion on the minimum level of fidelity required to develop and conduct gaming simulations in a valid way. Method. We investigate the validity by using training sessions in conjunction with questionnaires. We based the approach and questionnaires on the earlier work of Raser. Results. Our results show that the validity of the gaming simulation ranges from medium to good. They also show that while the fidelity of the gaming simulation is not like the real-world operating conditions, this does not reduce validity to low levels. Conclusions. We conclude that the gaming simulation used in this study was of medium to good validity. We also conclude that maximum fidelity is not required in order to run a valid gaming simulation session. © 2016, © The Author(s) 2016.
Plantinga H.E.C.,ProRail |
Doree A.G.,University of Twente
Proceedings 30th Annual Association of Researchers in Construction Management Conference, ARCOM 2014 | Year: 2014
In public procurement, most contractors view the qualifying procedures they are obliged to follow as time consuming and wasteful. For one category of public clients, EU rules offer an alternative to qualifying for each project. Public clients operating in the water, energy, transport or telecommunications sectors may establish and operate a so-called 'qualification system'. This offers contractors the opportunity to qualify for a period of time rather than an individual project. The reasons for applying such a qualification system seem traditionally to be rooted in reducing transaction costs, particularly where the administrative demands are significant relative to the typical value of contracts. As such, it may seem self-evident that a client's choice between the two approaches should be based on cost efficiency considerations. However, cost efficiency may not be the only motive behind employing a qualification system. A case study is presented here that examines the evolution of such a system and the corresponding reasoning by its operator. While exploring the usability of a conceptual model for managing procurement knowledge, additional reasons for operating the qualification system are reconstructed by exposing the implicit organizational knowledge. Initial results show that formal reasons are combined with implicit ones. These implicit reasons are found to be key in explaining the current utilization of the qualification system. Over time, implicit reasons get included in the reasoning process and come to dominate the original formal reasons. Without proper explication of these reasons, the real value of the qualification system may remain undetected. The contributions of this paper are twofold. First, it reports a case study in which the usability of a model developed for managing procurement knowledge is explored. Second, this paper offers a first insight into the evolution of a qualification system and the corresponding reasoning by its operator.
Plantinga H.E.C.,ProRail |
Doree A.G.,University of Twente
Proceedings 29th Annual Association of Researchers in Construction Management Conference, ARCOM 2013 | Year: 2014
For fifteen years, the Dutch railway agency (ProRail) has implemented various alliance elements in its procurement strategies. Several project alliancing applications have been developed and applied in succession, ranging from a limited shared risk domain to a directly tendered full alliance model. The progress seems to be evolutionary rather than planned. The emergence of these alliance variants suggests implicit motivations and expectations. Changing the implicit reasoning to explicit logic could help in the evaluation and development of alliance approaches, from project-based evolutionary adaptations to a conscious planned strategy. This study considers a number of alliance projects. The variation amongst these projects is mapped against a number of criteria derived from the literature. Contracting plans, the tendering board's minutes, contracts and other policy documents were scanned and interviews were held with key players to reconstruct the motivations for the various alliance approaches. The initial results confirm that changes and choices made in terms of the particular alliance domain are mostly implicit and only sparsely explained by motivations. This paper will present a first overview of ProRail's alliancing variants, corresponding motivations and expectations, plus more explicit insights into the prevailing implicit reasoning. This study offers a first step in mapping the variation in alliance methods, evaluating their effects and moving the implicit evolutionary development of alliance methods towards more deliberate planned choices in future alliancing variations. The next step in the research project will be to verify the validity of the expectations and logic regarding alliancing.
Xin L.,Technical University of Delft |
Markine V.L.,Technical University of Delft |
Wear | Year: 2016
In this paper a numerical procedure for analysis of rolling contact fatigue crack initiation and fatigue life prediction for the railway turnout crossing is presented. To analyse wheel-rail interaction, a three-dimensional explicit finite element (FE) model of a wheelset passing a turnout crossing is developed to obtain the dynamic responses such as the contact forces, displacements and accelerations as well as the stresses and strain in the crossing nose. The material model accounting for elastic-plastic isotropic and kinematic hardening effects in rails is adopted. The fatigue life of the rails is defined as the time to rolling contact fatigue crack initiation. In predicting the fatigue life Jiang and Sehitoglu model is used, which is based on the critical plane approach. Using the FE simulation results the ten critical locations on the crossing nose susceptible to crack initiation are determined first. Then, using the fatigue model the critical planes in these locations are obtained and the number of cycles to fatigue crack initiation is calculated for each location, based on which the most decisive location and the crossing life is determined. The results of the numerical simulations are presented and discussed. © 2016 Elsevier B.V.
Pel A.J.,Technical University of Delft |
Bel N.H.,ProRail |
Transportation Research Part A: Policy and Practice | Year: 2014
Transit passengers' response to crowded conditions has been studied empirically, yet is limitedly included in transport models currently used in the design of policy and infrastructure investments. This has consequences for the practical applicability of these models in studies on, for instance, timetabling, train capacity management strategies, project appraisal, and passenger satisfaction. Here we propose four methods to include the effect of crowding, based on existing studies on passengers' perception and response as well as often-used crowding indicators. These four alternative methods are implemented in the train passenger assignment procedure of the Dutch national transport model, and evaluated with respect to their impacts on the model results for the Dutch railway network. The four methods relate to four different ways in which an additive trip penalty and/or time-multiplier can be incorporated in the train utility function for different travel purposes, to capture the disutility of crowding as measured by the load factor. The analyses of the test case favor the hybrid method using both a boarding penalty (capturing seat availability upon boarding) and a time-multiplier (capturing physical comfort and safety throughout the trip). This method produces consistent results, while the additional computational effort that it imposes is acceptable. Further empirical underpinning is needed to conclusively show which of these methods best captures passengers' response behavior quantitatively (for different travel purposes and conditions). © 2014 Elsevier Ltd.
Markine V.L.,Technical University of Delft |
Steenbergen M.J.M.M.,Technical University of Delft |
Wear | Year: 2011
A railway switch (turnout) is a very important element of the railway infrastructure. Due to the discontinuity in the rail geometry high dynamic amplification of the wheel loads occurs in the crossing nose. These dynamic forces can severely damage the turnout structure. Especially the high-frequency impact loads (the so-called P1 forces) are responsible for RCF damage on the crossing nose. In the present study the relationship between the elastic properties of the turnout supporting structure (such as the rail pads, under sleeper pads and ballast mats) and the occurrence of RCF damage on the crossing point has been investigated. The RCF damage can be reduced by decreasing the high-frequency dynamic forces in the crossing nose. The dynamic interaction between the railway vehicle and track structure has been analysed numerically using DARTS_NL software (TU Delft). The performance of the turnout has been assessed using numerical simulations in which a railway vehicle (the ICE locomotive) was running through the turnout at 140. km/h. In this simulation only the vertical dynamic forces in the crossing point have been considered: lateral behaviour was disregarded. The results of the parameter analysis have demonstrated that by varying the elastic properties of the supporting track structure the forces on the crossing point can be significantly reduced. It was also shown that by varying substructure elasticity the dynamic forces on other track components such as sleepers and ballast can be reduced as well. © 2010 Elsevier B.V.
Li Z.,Technical University of Delft |
Dollevoet R.,ProRail |
Molodova M.,Technical University of Delft |
Zhao X.,Technical University of Delft
Wear | Year: 2011
This paper presents evidences obtained by field monitoring, measurement and survey to show the validity of some numerical predictions about squat growth. The predictions concerns a postulated squat growth process, the relationship between the dynamic contact force and the corrugation-like wave pattern that often follows squats, the high frequency wheel-rail interaction related to squats, and the influence of tangential force on squat growth. The observations reveal signature tunes of squats which may be used for early detection of squats, show the necessity to include high frequency dynamic wheel-rail interaction in squat-related analyses, and provide evidence of relationship between rolling stock performance and squat initiation and growth. In validating the numerical results the model is also verified for its applicability to analyses of squat-related problem and other problems similar in nature. The model can be employed for the solution of three-dimensional frictional rolling contact problems. It can also be used for analyses of loading conditions of wheel-rail contact at short wave defects, and the associated damages such as wear, plastic deformation, fatigue and corrugation. © 2010 Elsevier B.V.
Markine V.L.,Technical University of Delft |
Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit | Year: 2011
The article describes a numerical procedure for optimum design of a railway wheel profile. The optimization performed using the optimality criteria based on a rolling radius difference function, which account for the reduction ofwear and contact stresses aswell as for stability of the vehicle. As a general optimization technique the multipoint approximations method is employed. The described procedure has been applied to improve the wheel profile design for a passenger train that was suffering from rolling contact fatigue defects in the rails and wheels. In order to account for uncertainties inherent to the wheel production process, the robustness of the optimum wheel profile was analysed. The failure criterion was formulated using the vehicle stability requirement. The failure probability was estimated using the Monte Carlo method and modified Latin hypercube sampling technique. The results are presented and discussed. © Authors 2011.
Hoogzaad S.N.,MP |
Notes on Numerical Fluid Mechanics and Multidisciplinary Design | Year: 2015
At railroad yards passenger trains are parked overnight and prepared for the next day and/or freight trains are shunted. These activities are diverse and commonly processed ad-hoc. Noise permits for railroad yards are in contrast inflexible. More activities take place at the railroad yards as the intensity on the tracks increases. Noise production is increased and the permit becomes more and more restrictive. ProRail is the railway infrastructure manager and responsible for complying with the community noise limits from the environmental laws. ProRail is also responsible for the yearly capacity allocation process. A noise propagation model is used for the calculation of the noise levels. Building such a model is time-intensive so the noise impact of only one mode of operation of the yard is investigated, leaving other modes of operations to be unknown. M+P developed a software program “Dynamic Noise Model” (DNM) on behalf of ProRail. Many possible modes of operation can be evaluated with just a push of a button with this calculation tool. This makes it easier to find alternative modes of operations which produce less noise. Optimization of the use of the yard within noise limits is possible. A DNM also can be used to make informed decisions about taking noise measures or applying changes to the activities in the yard. The DNM uses a database with two datasets. The first set has the attenuations between standardized processes and receivers. These attenuations are calculated in advance with a propagation model. The second dataset contains all sound power levels (SPL) by train type. This is combined with a list of all activities taking place in the railroad yard, resulting in the total SPL for all receiver positions. ProRail is going to use the DNM for a large number of railroad yards for testing for compliance with environmental laws during the capacity allocation process. © Springer-Verlag Berlin Heidelberg 2015.
Meijer S.A.,Technical University of Delft |
Mayer I.S.,Technical University of Delft |
van Luipen J.,ProRail |
Simulation and Gaming | Year: 2012
Stakeholders in the Netherlands' rail cargo sector exhibit strategic behavior that causes irregularity and unpredictability in freight trains. This leads to the suboptimal use of scarce rail capacity. The authors present the results of a research project that used gaming to explore and validate alternative organizational methods for the management of rail cargo capacity with decision makers and subject matter experts from ProRail, the Netherlands' railway infrastructure manager. Various scenarios for the organization of rail cargo capacity management were played out, tested, and extensively debriefed in three project phases. The gaming sessions demonstrated that open information sharing among stakeholders does not depend on the introduction of price mechanisms and is, indeed, a more effective way of managing capacity. The authors conclude that it is vital to introduce gaming gradually and build up organizational acceptance for this method. However, once acceptance has been achieved, gaming can generate valuable insight into strategic behavior and the performance of sociotechnical infrastructures. © 2012 SAGE Publications.