Ballasted tracks are the commonly used railway track systems with constant demands for reducing maintenance cost and improved performance. Elastic layers increasingly improving ballasted tracks. In order to better understand effects of elastic layers, physical understanding at ballast particle level is crucial. Here, discrete element method (DEM) investigate - under sleeper pad ( USP ) sleeper/ballast interface mat UBM ballast/bottom on micro-mechanical behavior ballast. DEM model, Conical...

Railway ballast is an angular and coarse material, which demands careful DEM modelling validation. Particle shape often modelled in high accuracy, thus leading to computational expensive models. Whether this effort will increase the model's overall prediction quality also vitally depend on used contact law validation process. In general, a model validated using different types of principal experiments can be considered more trustworthy simulating other load cases. Here, two railway are...

The condition of railway infrastructure is currently assessed by track recording cars, wayside equipment, onboard monitoring techniques and visual inspections. These data sources deliver valuable information for managers on the asset’s but are mostly carried out in time-based intervals. This paper examines potential fibre optic cables, which already installed cable troughs alongside tracks, to monitor conditions. sensing technique, known as distributed acoustic/vibration (DAS/DVS), relies...

Research on track quality behavior has been extensively published, and many different approaches have presented to describe the process of quality. The research goal this paper is form a basis for data-driven tamping prediction based analyses over time. A database containing asset information, executed maintenance tasks, measuring data some 4,400 km Austrian rail network in time sequence 16 years available. modified standard deviation vertical geometry identified as an ideal indicator...

When a wheel passes over rail surface irregularity, the resulting vehicle excitations lead to application of additional system forces both track and vehicle. These contribute an accelerated geometry deterioration, which in turn results increased costs. In recent paper, clear correlation between presence irregularities poor quality was demonstrated. Rail thereby were quantified by raw data chord-based optical measurement mounted on regular recording Austria. This paper deals with...

Condition assessment and maintenance planning of railway infrastructure is a prerequisite for safe reliable train operation. As the loads are constantly increasing, condition track must also be further developed. Existing methods can describe well in many cases, but they will reach their limits with faster deterioration processes shorter time windows inspection maintenance, both associated higher loads. This development only countered an increased understanding system better component...

Track engineers face increasing cost pressure and budget restrictions in their work today. This leads to growing difficulty legitimizing crucial maintenance renewal measures. As a result, infrastructure managers must ensure they invest all available financial resources as sustainably efficiently possible. These boundary conditions require an objective tool enabling both component-specific condition evaluation preventive with planning. The present research introduces such for railway tracks...

Track deterioration models (TDMs) help to allocate maintenance work (direct costs) vehicle runs. Furthermore, these demonstrate the impact of rolling stock properties on infrastructure. This paper review provides an overview state art in railway track modelling and outlines research potential this domain. The main focus lies ballast degradation, rail surface wear fatigue, their description empiric analytic formula. basis for discussion is formula Graz University Technology. While TDM...

Today’s railway transport is built upon high-performance infrastructure. Cost-effective yet sustainable infrastructure presumes tracks with a precise and durable geometry. At ballasted tracks, the geometry created restored through tamping machines, which position track panel compact ballast beneath sleepers. It commonly agreed that compaction plays an important role in long-term stability of track. Yet, there no method available allows direct correlation between compactness Available studies...

Short wavelength rail defects or short-wave effects of have a significant influence on the system behaviour railways. The additional dynamic loads due to component wear and general quality track is shown by several research papers. However, described effect cannot yet be quantified comprehensively. This paper attempts fill this gap. With help extensive data analysis, we can show that lead geometry up 50% worse than average. Furthermore, examples illustrating untreated welded joints...

Research and development concerning railways aim to either increase speed for passenger transport systems or allow higher axle loads. Developments in the last decades show a big success, heavy haul as well high operation. While track was practically destroyed by record run of 1955 (331 km/h respectively 205 mph) 2007 with 574.8 (360 did not cause any problems. In this time period could be developed towards stability preciseness due implementation mechanized maintenance subsequent heavier structures.

A detailed and serious cost calculation is a precondition for competitive offer of railway traffic services in future. This task does not only concern the Train Operating Companies (TOCs), but also Infrastructure Managers (IMs) when transferring infrastructure costs into track access charges. These charges are subject to discussions since they were foreseen European regulations back 1990-ies first time. The principle, charge “cost that directly incurred as result operating train service”,...

The positive effects of under sleeper pads have already been proven by track and laboratory tests worldwide. In Austria, padded concrete sleepers reduce deterioration 50 percent therefore used as standard components since 2010. As the increase material costs, many infrastructure managers discussed idea covering costs reducing ballast bed thickness. Technically, this approach (less ballast) is feasible, elasticity protect ballast. Further, lead to higher rail deflection distribution load more...

Turnouts are important components of railway infrastructure that require more attention as they must be frequently maintained. To transfer the resultingly high investment costs into a correspondingly long service life, effects all maintenance decisions identified. It is necessary to objectively weigh impact activities and optimum point in time for their execution. make these decisions, information about condition whole system well individual available. This paper presents model describing...

Tamping needs to guarantee safety in limiting geometric failures isolated points, reduce dynamic forces by a smooth through-going longitudinal level, and provide certain riding comfort for passengers. Although different methods are applied describe geometry deterioration, the amount of tamping needed is seldomly addressed. In this work, we evaluated compared regimes their long-term consequences extrapolating level track. Forecasting beyond one action precise positioning measurement data...

Predictive maintenance can help infrastructure managers to reduce costs and improve railway availability while ensuring safety. However, its accuracy depends on reliable data from various sources, especially track measurement data. When analysing over time, historical actions must be considered, as otherwise the interpretation of would misleading. This research aims address inconsistencies in recorded by detecting unrecorded works through geometry evaluations. The main goal is provide...

Managing head checks is a crucial task for an infrastructure manager as in case of deep cracks, rails can break and, thus, accidents might be the consequence. Many managers use vehicle-mounted eddy-current testing detecting cracks. This sufficient guaranteeing safe railway operation applying reactive maintenance regime removing cracks pre-defined depth. Moving this towards predictive only possible through assessing crack growth. Establishing stable deterioration function needs sound data...

For future requirements, asset management of turnouts needs to rely on data-based assessment tools. These tools must enable the quantification quality behaviour and identify causes poor behaviour. In this paper, we provide a toolbox addressing these requirements. We use track geometry as main criterion for in combination with additional indicators, each associated different component, understand turnout performance. The is applied five similar compare their It revealed that one performs...