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-Installed sensors to monitor the railway track: (a) humidity probe (b) vertical strain gage (c) accelerometer (d) horizontal strain gage (e) anchored displacement sensor (f) weather station (g) temperature probe.
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Ballast deterioration, under dynamic loads, remains an important issue on high-speed tracks that can lead to high maintenance costs. This ballast deterioration leads to settlements. Several studies have shown that these settlements were linked to high accelerations produced in the ballast by high-speed train (HST) passages. The solution with bitumi...
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Context 1
... objective of the instrumentation is to monitor dynamic responses of the different structures, and in particular to better understand the effects of the granular or asphalt sublayer on dynamic behavior and track durability. The following sensors (Figure 4), chosen and implemented by IFSTTAR, are used to monitor the different sections: ...
Citations
... The level of vehicle maintenance required is contingent upon the cumulative distance driven by the vehicle within a recurring time frame, such as days, months, or years (Caban et al., 2019). Damage to vehicle parts can lead to high maintenance costs (Khairallah et al., 2019). Car maintenance deals with fuel consumption and EMI, emissions of pollutants, and international combustion that also impact the environment (Mrozik & Merkisz-Guranowska, 2021 4 automobiles in supporting family groups is a prominent issue that should be taken into account (Blumenberg et al., 2022). ...
Objective: The main aim of this study is to investigate the influence of brand image and perceived price on customer loyalty, with a focus on the role of customer satisfaction as a mediating variable. Theoretical Framework: The provision of car maintenance services is a lucrative business potential in the automotive industry, as consumers have an urgent need to ensure proper care and maintenance of their vehicles. The automotive after-sales market covers a wide range of operations, including many aspects such as post-purchase vehicle maintenance and the last phase of vehicle life. It includes all activities related to spare parts and after-sales service. Method: The demography being examined comprises the customer base of the Auto2000 West Sumatra workshop. The research study used a sample size of 254 people. The research used a purposive sampling methodology. The data analysis conducted in this study was performed using the SmartPLS software version 3.2.9. SmartPLS is a software application that facilitates researchers in analyzing data to investigate models. Results and Discussion: The establishment of strong and reliable relationships between consumers and organizations is an important determinant of true client loyalty. Evaluating customer loyalty requires the use of measures centered on customers' propensity to provide recommendations or engage in favorable communications, along with their intention to make repeat purchases and pay higher prices. Research Implications: Research has significant value for companies in increasing consumer loyalty. The suggested conceptual model aims to improve understanding of how customer loyalty can be improved by integrating the quality of service quality, price fairness, customer happiness, brand image, and trust. Originality/Value: The management of company models requires a serious approach, as changes can have a significant impact on the way companies operate and generate revenue. To increase the revenue of various companies, research and recommendation systems emerged over the past decade and consist of valuable services.
... Particularly, bituminous sub-ballast is considered to allow for improving the track perform ance by increasing the strength of the sub-structure and reducing the trend to settlement as well as the stress and permeability over the foundation (Sol-Sánchez et al., 2016;Yu et al., DOI: 10.1201/9781003222910-13 2019). Moreover, there are other technical benefits such as reducing acceleration peaks in bal last layer (Asphalt Institute, 1998;Fang et al., 2011;Khairallah et al., 2019). ...
... In order to monitor and compare the behavior of the different track structures, the BPL track was equipped with a fine adequate instrumentation, consisting of more than 100 sensors distributed over 4 different test sections, covering both granular and bituminous sub-layers and different types of soil [21]. ...
... Passing HST characteristics are known, with increasing speeds ranging from 160 to 352 km/h. The study of the measurements recorded during this phase have been presented in [21] and have demonstrated that, during the speed-up test phase, the acceleration levels under the ballast increase with HST velocity for all types of structure. The comparison of the data between the structures with and without GB layer has revealed that the presence of the GB layer below the structure reduces the acceleration levels under the ballast responsible for its deterioration. ...
... The HSL track instrumentation is described in detail in [21][22]. Fig. 3 presents the layout of the instrumentation for accelerometers, displacement sensors, vertical and horizontal strain gauges for the three instrumented sections: ...
Tamping and ballast wear, due to dynamic stresses, lead to frequent and costly maintenance operations. To mitigate the impact, an innovative track structure combining a bituminous (asphalt concrete) layer below the ballast has been built on the Bretagne-Pays de la Loire High-Speed Line (BPL HSL). The track is intended to reduce the amplitude of the accelerations produced by passing High-Speed Trains (HST) which are the main reason for the settlement of ballast. BPL HSL includes 105 km of asphalt concrete sub-layer below the ballast and 77 km of granular sub-layer. In order to study the dynamic responses of these different structures, some track sections have been instrumented with anchored deflectometers, accelerometers, strain gauges and temperature probes. The aim of this paper is to present the results achieved after four years of commercial traffic. The data processing methods developed for this acquisition phase and the measurements of the substructure deflection, the vertical accelerations under ballast, and the vertical and horizontal strain of the various sections were presented. Deflection measurements, vertical strains and vertical accelerations peaks at the top of the sub-layer are compared between the granular and the bituminous track structures and shows that there is no evolution of the measurements during the four years of monitoring. The study clearly demonstrated that the presence of the bituminous layer in the structure reduces the acceleration levels under the ballast that cause its deterioration. Such conclusions suggest that a bituminous sub-layer might contribute to lower track maintenance needs over the service life of the line, decreasing operational costs and increasing capacity.
... The full instrumentation set up on the various sites is detailed in [19]. Accelerometers are positioned at several depths in the structure: at the top of the asphalt concrete layer and at the top and bottom of the granular layer. ...
... Data from both acquisition phases was treated and evaluated. Measurements made on the granular and bituminous sections during the speed up phase are presented and compared in a previous paper [19]. The study clearly demonstrated that the presence of a bituminous sublayer reduces acceleration levels under the ballast, contributing to the stability of the ballast layer. ...
... Using this calculated mean curves, maximum and minimum accelerations and displacements, corresponding to a train passage, were calculated. This treatment is detailed in [19]. Mean curves and peak values of the sensor measurements were used for comparison with the ViscoRail simulations. ...
The “Brittany - Loire” high-speed line (HSL BPL), connecting the cities of Rennes and Le Mans is the first large-scale application, in France, of ballasted tracks with bituminous sublayer and varied subgrade conditions. To evaluate the behaviour of this new type of track structure, and validate the design assumptions, it was decided to set in place a monitoring system, to monitor the mechanical response of the track. For that purpose, three track sections were instrumented during construction using accelerometers, anchored deflection sensors, strain gauges and temperature probes.
The objective of this paper is to analyse the response of three instrumented track sections of the HSL BPL, either with a bituminous or a granular sublayer, and to model their response using a dynamic model, considering a viscoelastic multilayer structure subjected to moving loads, implemented in the ViscoRail software. From the numerical point of view, the objective was to verify the capacity of ViscoRail to simulate the response of the three BPL sections, using as much as possible a unique set of mechanical parameters, while considering the specificities of each sections. The comparison between the modelling results and the in situ measurements indicates that the model is able to reproduce the main features of the dynamic response of railway tracks. In particular, the role of the asphalt concrete layer, which tends to reduce vertical accelerations in the ballast layer is well reproduced by ViscoRail.
... To guarantee a satisfactory longterm behaviour of the track and to reduce geometric irregularities, several studies have considered the use of alternative bituminous materials to substitute, partly or completely, the traditional granular layers. The studies are based on different approaches such as field experience observations (Albalat et al., 2011;Alves, 2018;Cardona et al., 2016;Khairallah et al., 2019;Robinet & Cuccaroni, 2010;Rose et al., 2011;, numerical simulations (Albalat et al., 2011;Di Mino et al., 2012;Huang et al., 1987;Rangel et al., 2015;Teixeira et al., 2010), and laboratory testings (Di Mino et al., 2015;D'Angelo et al., 2016;Esmaeili et al., 2014;Pirozzolo et al., 2017;Sol-Sánchez et al., 2016;Yu et al., 2019). The subballast layer plays an important role as part of the railway track infrastructure and it has a significant contribution to the mechanical behaviour of the track. ...
The use of bituminous subballast (BS) in railways has gained importance due to structural and geometrical enhancing properties of these infrastructures. Oftentimes, during renovations the paving quality control of bituminous mixtures is compromised due to reduced time span. To verify the effects of significant air voids content variation on the mechanical response of railway tracks, this paper performed a 3-D numerical modelling of a Brazilian railway renovated with BS. First, the BS was characterised in laboratory for model inputs. Then, 3-D numerical models were developed assuming two constitutive behaviour for the BS: linear elastic and linear viscoelastic. An all granular track was also simulated for comparisons. Numerical results were compared with actual instrumented test section. As expected, displacements on foot-of-rail and stresses on the subgrade were reduced when using BS. Moreover, the different air voids content of the bituminous mixture evaluated herein caused low variation in the overall track response.
... Accelerometers, weather stations, anchored displacement sensors, horizontal and vertical strain gauges, moisture probes and temperature sensors were installed on each section. The instrumentation is detailed in [1][2]. The sensors are connected by cables to the data acquisition systems. ...
Tamping and ballast wear, due to dynamic stresses, lead to frequent and costly maintenance operations. To mitigate this problem, an innovative track structure with an asphalt concrete layer under the ballast was built on the Bretagne-Pays de la Loire High-Speed Line (BPL HSL). It is intended, among other things, to reduce the amplitude of the accelerations produced at the passage of High-Speed Trains (HST), which are a major cause of ballast settlements. BPL HSL includes 105 km of asphalt concrete sub-layer under the ballast and 77 km of granular sub-layer. In order to study the dynamic responses of these different structures, four track sections were instrumented using, among others, accelerometers, strain gauges and temperature probes. In this paper, we present the track instrumentation, the acquisition system installed to collect all the measurements, and the comparative results of dynamic and mechanical behavior between structures since July 2017, when the BPL HSL was opened to commercial traffic.
... Based on this study, the asphalt underlayment section presented better drainage properties and embankment protection. Another point about using asphalt underlayment is that the ballast layer provides a kind of protection against severe temperature changes [92,93]. In addition, investigations are ongoing by French railway authorities to develop an asphaltic layer as an alternative for freight traffic, especially in tunnels, to increase the tunnel gauge by decreasing the overall thickness of the track [94]. ...
Asphalt is a common material that is used extensively for roadways. Furthermore, bituminous mixes have been used in railways, both as asphalt and as mortar. Different agencies and research institutes have investigated and suggested various applications. These studies indicate the benefits of bituminous material under railways, such as improving a substructure's stiffness and bearing capacity; enhancing its dynamic characteristics and response, especially under high-speed train loads; waterproofing the subgrade; protecting the top layers against fine contamination. These potential applications can improve the overall track structure performance and lead to minimizing settlement under heavy loads. They can also guarantee an appropriate response under high-speed loads, especially in comparison to a rigid slab track. This review paper documents the literature related to the utilization of asphalt and bituminous mixes in railway tracks. This paper presents a critical review of the research in the application of asphalt and bituminous mixes in railway tracks. Additionally, this paper reviews the design and construction recommendations and procedures for asphalt and bituminous mixes in railway tracks as practiced in different countries. This paper also provides case studies of projects where asphalt and bituminous mixes have been utilized in railway tracks. It is anticipated that this review paper will facilitate (1) the exchange of ideas and innovations in the area of the design and construction of railway tracks and (2) the development of unified standards for the design and construction of railway tracks with asphalt and bituminous mixtures.
... (a) sensors for field monitoring[40] (b) Permanent deformation on surface of subgrade (c) Permanent strain on the surface of subgrade (d) Effect of atmospheric actions on subgrade permanent strain during initial years ...
Ballast railway system and non-ballast railway system, two main railway types, have encountered impeding challenges with the increasing axle loads, traffic volumes and speed. This field has therefore been seeking reliable and maintenance-free railway systems. Although Asphalt Based Materials (ABM) as possible solutions have attracted a lot of attentions, concerns on performance exist before their extensive application in railway systems around the world. For further promoting the application of ABM in practice, this review paper tried to comprehensively evaluate existing application forms in terms of design and construction, evaluation and performance, challenge and opportunity, as well as economy and environmental impact. In conclusion, their application experience in railway system demonstrated a problem-oriented developing trend. Six subfields of ABM were proposed in this study, including Asphalt Stabilized Ballast (ASB), Asphalt Underlayment (AUL), Asphalt Overlayment (AOL), Cement Asphalt Mortar layer (CAM), Asphalt Slab Track Bed (ASTB) and asphalt based impermeable layer. Each subfield showed positive effects as well as new challenges, and AUL, AOL and CAM were believed to be more reliable. To solve the challenges encountered by ABM, future studies were suggested to focus on the advancements in material property, structural design method, life cycle assessment, and optimization on materials and structure. Meanwhile, researches on modified test method and non-destructive tool were encouraged to provide essential data basis for construction and understanding the evolution of field performance of ABM. Consequently, the popularization and application of ABM around the world needed to be considered comprehensively according to local requirements and conditions.
... Asphalt mixtures were first involved in pavement construction in the early twentieth century [1] and have been introduced to rail infrastructure ever since the last decades [2][3][4]. It is demonstrated that an bituminous layer could improve both the stability and durability of track structures for passenger and freight transport [5,6]. https In Japan, asphalt roadbed was developed and has been used in slab track systems for many years, with a primary objective of creating a firm platform for concrete slab, reducing maintenance, and minimizing risks of settlement. ...
... In Italy, asphalt mixtures were first used for the construction of the Florence-Rome high-speed rail in the 1970 s, showing that the presence of bituminous sublayer in track structure would reduce train-induced vibrations passing to the surrounding environment. The French National Railway Company (SNCF) built a 3 km long trial section in the Ligne à Grande Vitesse Est européenne that links Paris and Strasbourg in 2005 and performed a four-year monitoring program to examine the effect of a bituminous sublayer on maintenance and structure durability during climate variations [5]. The first large-scale application of asphalt sublayer to track structure in France is the HSL Bretagne-Pays de la Loire, with trains traveling at a speed of up to 320 km/h [17]. ...
... In general, the stresses increase with rising speed, and show more outliers at high speeds. This scatters of subgrade response can be attributed to the stability loss in the ballast layer in the form of settlements and aggregate movements when it subjects to high-frequency loading [5]. Another potential cause is about the disturbance, induced by unavoidable ballast excavation, which would influence the contact state of earth pressure cells. ...
The bituminous underlayment has been introduced to ballasted track systems since the 1970s in some countries such as Italy, Spain, Japan, and the United States. In China, the interest in this technique arises recently in the construction of high-speed rails (HSRs). It is intended to provide better waterproof and damping performance and thereby to reduce maintenance costs by employing an asphalt layer beneath the ballast. To evaluate the response of the innovative track structure, a monitoring project has been implemented in trial sections of the Beijing–Zhangjiakou HSR in October 2019. Data were acquired at two instrumented substructures during integrated commissioning and testing with the same comprehensive inspection train CRH380AJ-0203 traveling at speeds ranging from 10 km/h to 295 km/h. One section was constructed with fully paved 10 cm thick asphalt concrete (known as asphalt support layer) overlying 60 cm thick graded gravel subgrade, and the other built with a 70 cm thick graded gravel platform supporting the ballast and track components. A total of 14 sensors that include integrated vibration sensors and earth pressure cells were mounted at the subgrade surface right beneath the rails and sleepers. The field measurements include vertical displacements, velocities, accelerations, and stresses under different train speeds, and data treatment and processing techniques are given in detail. Performance comparisons are made between the mechanical response of track substructure in bituminous and standard sections, with emphasis on acceleration measurements. The dynamic amplification factor (DAF) reaches 1.56 and 1.66 in standard and asphalt sections, respectively. The maximum value of extracted peak data points is preferable than the mean value in the performance evaluation of track substructure. Both sections show linear growth of frequency-weighted vertical acceleration levels (VALs) with train speeds; however, significant difference in non-weighted VAL among speeds occurs in the range of 8–20 Hz. The high stiffness and structural integrity of bituminous ballasted track foundations are demonstrated, while the damping and durability performance should be further investigated.
... The results presented in this paper only concern the speed-up phase. Comparisons between results obtained on the two structures, with granular and asphalt concrete sublayers, are detailed in (8). ...
The design and durability of high-speed railway lines is a major challenge in the field of railway transportation. In France, 40 years of feedback on the field behavior of ballasted tracks led to improvements in the design rules. However, the settlement and wear of ballast, caused by dynamic stresses at high frequencies, remains a major problem on high-speed tracks leading to high maintenance costs. Studies have shown that this settlement is linked to the high acceleration produced in the ballast layer by high-speed trains traveling on the track, disrupting the granular assembly. The “Bretagne–Pays de la Loire” high-speed line (BPL HSL), with its varied subgrade conditions, represents the first large-scale application of asphalt concrete (GB) as the ballast sublayer. This line includes 77 km of conventional track with a granular sublayer of unbound granular material (UGM) and 105 km of track with an asphalt concrete sublayer under the ballast. During construction, instruments such as accelerometers, anchored deflection sensors, and strain gages, among others, were installed on four sections of the track. This paper examines the instrumentation as well as the acquisition system installed on the track. The data processing is explained first, followed by a presentation of the ViscoRail software, developed for modeling railway tracks. The bituminous section’s behavior and response is modeled using a multilayer dynamic response model, implemented in the ViscoRail software. A good match between experimental and calculated results is highlighted.
