scholarly journals Optimisation of Transition Areas between Ballastless Track and Ballasted Track in the Area of the Tunnel Turecky Vrch

2018 ◽  
Vol 20 (3) ◽  
pp. 67-76
Author(s):  
Libor Izvolt ◽  
Jozef Harusinec ◽  
Michal Smalo
Keyword(s):  
Slovak Republic ◽  
Vertical Displacement ◽  
Vertical Acceleration ◽  
Track Geometry ◽  
Ballastless Track ◽  
Current State ◽  
Railway Infrastructure ◽  
Vertical Speed ◽  
The University ◽  
Transition Areas

The paper follows previously published papers in Communications – Scientific Letters of the University of Zilina No. 4/2014, No. 4/2015 and No. 4/2016, where were presented the results of the diagnostics of the track geometry of the experimental sections surrounding the portals of a new building of the Tunnel Turecky vrch. Based on the data obtained by comprehensive diagnostics, there can be stated that the problematic section in the slab track are the transition areas allowing the transfer of the vehicle between the line structures with a different bending stiffness. The comprehensive diagnostics was realised by the continuous method (measuring trolley KRAB), the results of which were verified by the results of the measuring car of ZSR and by the geodetic monitoring of the layout of the track, as well. Mathematical modelling of the transition areas was realized in the environment of the software ANSYS with the aim to optimise the structural solution of the existing transition areas, as well as of in the future built ones, within the modernization of the railway infrastructure of the Slovak Republic. The model of the existing transition area was structurally optimised –models were realised with application of the stiffening rails and with usage of the under sleeper pads. The model of the current state and the models of the optimised structural solutions of the transition areas were subsequently compared by the values of the vertical displacement, vertical speed and vertical acceleration.

Vertical Dynamics Analysis on Evaluation Standard of Ballastless Track Damping Effect

2013 ◽  
Vol 361-363 ◽  
pp. 1703-1708
Author(s):  
Zeng Wu ◽  
Jie Qing Li ◽  
Zhong Tao
Keyword(s):  
Kinetic Energy ◽  
Evaluation Criteria ◽  
Vertical Displacement ◽  
Vertical Acceleration ◽  
Evaluation Standard ◽  
Damping Effect ◽  
Ballastless Track ◽  
Numerical Simulation Methods ◽  
Train Speed ◽  
The Difference

Vibration and noise reduction was the trend of ballastless track, however, evaluation of different types of damping effect of the track was not easy to achieve. The orbit of the traditional vertical displacement of the components, to evaluate the damping effect of the acceleration was not accurate when the difference between the track structure larger. From the principle of energy conservation, the flexibility to select a long pillow, long pillow vertical, orbital plate of three ballastless track fragments, respectively, without the establishment of a vehicle - track couplin model, the vertical acceleration, the vertical track of the various components of displacement, acceleration, maximum kinetic energy was calculated out when train speed was 250km/h by numerical simulation methods. By analyzing the relationship between their body vertical acceleration and found that the largest track the existence of kinetic energy correlation between the changes in, made with the greatest kinetic energy damping effect as the track of one of the evaluation criteria, and it was easy to implement.

scholarly journals Diagnostics of Track Quality of Ballastless Track and Transition Areas in Vicinity of Portals of Tunnel Turecky vrch

2016 ◽  
Vol 12 (1) ◽  
pp. 2-12 ◽  
Author(s):  
Michal Šmalo
Keyword(s):  
Track Structure ◽  
Track Geometry ◽  
Ballastless Track ◽  
Ballasted Track ◽  
Transition Areas ◽  
Track Quality

Abstract The paper deals with the partial results of diagnostics of experimental sections of ballastless track Rheda 2000® and transition areas between ballastless and ballasted track structure around portals of tunnel Turecky vrch after six measurement cycles. The paper presents differences between each operational measurement and the measurement before putting sections into operation, which indicates a development of track geometry quality.

Railway Ballast Permeability and Cleaning Considerations

2017 ◽  
Vol 2607 (1) ◽  
pp. 24-32 ◽  
Author(s):  
Scott Schmidt ◽  
Sagar Shah ◽  
Maziar Moaveni ◽  
Blake J. Landry ◽  
Erol Tutumluer ◽  
...  
Keyword(s):  
Ride Quality ◽  
Railway Ballast ◽  
Track Geometry ◽  
Fine Grained ◽  
Current State ◽  
Discharge Velocity ◽  
External Sources ◽  
Constant Head ◽  
The University ◽  
The Relationship

The unbound aggregate ballast layer is a major structural and drainage component of railroad track that is known to degrade over time. Progressive degradation increases the fine-grained content of the ballast layer through particle breakage and abrasion or from external sources, such as subgrade or foreign material. The point at which ballast should be cleaned of these materials to avoid significant problems for drainage, track geometry, or ride quality is not well known. This paper attempts to ascertain the current state of the art on ballast permeability by reviewing previous studies, to fill any gaps by generating new laboratory test data, and to begin developing ballast cleaning considerations. A new and relatively simple test apparatus, the University of Illinois Constant Head Aggregate Permeameter, was used to study railroad ballast permeability as a function of degradation. Results of tests performed indicate that the cleaner the ballast, the more nonlinear the relationship between discharge velocity and hydraulic gradient, contrary to the findings of previous studies. In addition, flow decreased greatly after small increases in ballast degradation. Detailed findings related to the characteristics of flow—other than whether flow is impeded by in-service ballast condition—may not be extremely useful for rail practitioners because the amount of ballast degradation is difficult to determine in the field. However, the emerging ballast imaging technology described may be able to provide railroad personnel with a threshold for when ballast should be cleaned.

Challenges to Foster Resilience

2018 ◽  
Vol 5 (2) ◽  
pp. 80
Author(s):  
Tania Maritza Díaz Macías ◽  
Leila María Álava Barreiro ◽  
Diana Stefani Velásquez García
Keyword(s):  
Inclusive Education ◽  
Inclusive Development ◽  
Educational Policies ◽  
Process Of Change ◽  
Higher Education System ◽  
Whole Process ◽  
Current State ◽  
The University ◽  
Conceptual Evolution ◽  
Scientific Pedagogical

The work aims to provoke critical educational reflections on the current state of the scientific-pedagogical conception of inclusive education in the university context. In this sense, we are aware of the existence of an extremely positive conceptual evolution in recent times. It is necessary to articulate new discourses and teaching practices that project and illuminate the idea that inclusive education as a permanent process of change in education and for which the development of psychological activities outlined in resilience can play an important role. The Ecuadorian higher education system has experienced, for a few years, changes of great pedagogical interest. In this framework, a whole process of generating educational policies and inclusive education is shown, taking as a framework the professors and managers of the Technical University of Manabí (UTM) (Ecuador), to contribute to the greater inclusive development of the said university. The main challenges for university institutions regarding fostering the resilience of the academic process are presented.

The Indian University in a Comparative Perspective

2018 ◽  
Author(s):  
N.R. Madhava Menon
Keyword(s):  
Higher Education ◽  
Competitive Advantage ◽  
Higher Education Institutions ◽  
Knowledge Society ◽  
Comparative Perspective ◽  
Policy Changes ◽  
University System ◽  
Current State ◽  
The World ◽  
The University

The purpose of looking at Indian universities in a comparative perspective is obviously to locate it among higher education institutions across the world and to identify its strengths and weaknesses in the advancement of learning and research. In doing so, one can discern the directions for reform in order to put the university system in a competitive advantage for an emerging knowledge society. This chapter looks at the current state of universities in India and highlights the initiatives under way for change and proposes required policy changes.

scholarly journals Spirals of Sustainable Academic Motivation, Creativity, and Trust of Higher Education Staff

2021 ◽  
Vol 13 (13) ◽  
pp. 7057
Author(s):  
Martina Blašková ◽  
Dominika Tumová ◽  
Rudolf Blaško ◽  
Justyna Majchrzak-Lepczyk
Keyword(s):  
Higher Education ◽  
Academic Motivation ◽  
Slovak Republic ◽  
Point Of View ◽  
Scientific Management ◽  
Administrative Staff ◽  
Sustainable Systems ◽  
New Concepts ◽  
Future Improvement ◽  
The University

Sustainability has to penetrate more and more into higher education. It should not focus only on traditional elements. It should also enter new, but for future improvement, extremely important areas. Based on this premise, creativity and motivation, when additionally interconnected and supported by trust that is provided and achieved, decide on the progress and sustainability of universities. This connection is gaining importance especially from the point of view of building solid foundations and mechanisms that functionally preserve the potential effects of these elements in the future. For this reason and following the nature, importance, and content of sustainable academic motivation (SAM), the paper introduces two new concepts: sustainable academic creativity (SAC) and sustainable academic trust (SAT). For further original contributions, the paper hypothesizes the existence of mutual—spiral—relations of sustainable academic motivation (SAM), sustainable academic creativity (SAC), and sustainable academic trust (SAT). The empirical section tests the validity of this claim in the universities of two countries: the Slovak Republic and Poland. A survey performed on a sample of n=181 pedagogical, scientific, management, and administrative staff in higher education confirms the existence of these spirals. The results indicate the spiral effect of motivation when connected with creativity and trust and show that it is accented by the crucial principles of sustainability (responsibility, novelty, usefulness, progress, etc.). Therefore, the paper’s conclusion contains the explanations for the potential occurrence of three types of sustainably mutual systems and complexes. These are: (a) individual sustainable systems of SAM, SAC, and SAT; (b) group/sectional sustainable systems of SAM, SAC, and SAT; and (c) the global sustainable complex of SAM, SAC, and SAT in the university.

scholarly journals Melite Civitas Romana in 3D: Virtualization Project of the Archaeological Park and Museum of the Domus Romana of Rabat, Malta

2021 ◽  
Vol 7 (1) ◽  
pp. 51-83
Author(s):  
Davide Tanasi ◽  
Stephan Hassam ◽  
Kaitlyn Kingsland ◽  
Paolo Trapani ◽  
Matthew King ◽  
...  
Keyword(s):  
Laser Scanning ◽  
Structured Light ◽  
Terrestrial Laser Scanning ◽  
Archaeological Site ◽  
South Florida ◽  
Virtual Museum ◽  
Current State ◽  
Structured Light Scanning ◽  
The University ◽  
Archaeological Excavations

Abstract The archaeological site of the Domus Romana in Rabat, Malta was excavated almost 100 years ago yielding artefacts from the various phases of the site. The Melite Civitas Romana project was designed to investigate the domus, which may have been the home of a Roman Senator, and its many phases of use. Pending planned archaeological excavations designed to investigate the various phases of the site, a team from the Institute for Digital Exploration from the University of South Florida carried out a digitization campaign in the summer of 2019 using terrestrial laser scanning and aerial digital photogrammetry to document the current state of the site to provide a baseline of documentation and plan the coming excavations. In parallel, structured light scanning and photogrammetry were used to digitize 128 artefacts in the museum of the Domus Romana to aid in off-site research and create a virtual museum platform for global dissemination.

Dynamic Characteristic Analysis of Irregularity under Turnout by Vehicle-Turnout Rigid-Flexible Coupling Model

2014 ◽  
Vol 945-949 ◽  
pp. 591-595 ◽  
Author(s):  
Meng Chen ◽  
Yan Yun Luo ◽  
Bin Zhang
Keyword(s):  
Finite Element ◽  
Longitudinal Direction ◽  
Element Model ◽  
Vertical Displacement ◽  
Coupling Model ◽  
Interaction Force ◽  
Vertical Acceleration ◽  
Characteristic Analysis ◽  
Flexible Coupling ◽  
Multi Body

Finite element model of track in frog zone is built by vehicle-turnout system dynamics. Considering variation of rail section and elastic support, bending deformation of turnout sleeper, spacer block and sharing pad effects, the track integral rigidity distribution in longitudinal direction is calculated in the model. Vehicle-turnout rigid-flexible coupling model is built by finite element method (FEM), multi-body system (MBS) dynamics and Hertz contact theory. With the regularity solution that different stiffness is applied for rubber pad under sharing pad of different turnout sleeper zone, analysis the variation of vertical acceleration of bogie and wheelset, rail vertical displacement and wheel-rail interaction force, this paper proves that setting reasonable rubber pad stiffness is an efficient method to solve rigidity irregularity problem.

scholarly journals The Influence of the Track Parameters on Vibration Characteristics of Subway Tunnel

2018 ◽  
Vol 2018 ◽  
pp. 1-12 ◽  
Author(s):  
Wenbo Shi ◽  
Linchang Miao ◽  
Junhui Luo ◽  
Honglei Zhang
Keyword(s):  
Soft Soil ◽  
Power Level ◽  
Coupling Model ◽  
Calculation Model ◽  
Vertical Acceleration ◽  
Subway Tunnel ◽  
Ballastless Track ◽  
Train Operation ◽  
The Impact ◽  
Wheel Track

In soft soil areas, such as the Nanjing, it is very important to quantitatively analyze the dynamic behaviors of soft soils during the metro train operation. A nonlinear coupling model of wheel-track and a finite element calculation model of tunnel and soil were established based on the mechanical character of elastic supporting block ballastless track and the actual parameters of Nanjing soft soil. The time-variant vertical acceleration of the rail, the sleepers, and the surface of the tunnel can be calculated by the models, and the frequency dependence acceleration was verified by the fast Fourier transform algorithm. A modified vibration power level for human sensitivity was used to quantify the vibration energy of each part of the system, and the impact of the parameters in the model was evaluated. The results can be applied to the metro design and construction, which also can be the guidance during the tunnel construction.

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