Locomotive Horn Evaluation: Effectiveness at Operating Speeds

Wheel–rail impact loads and noise generated at railway crossings – Influence of vehicle speed and crossing dip angle

The development of operating speed models has been the subject of numerous research studies in the past. Most of them present models that aim to predict free-flow speed in conjunction with the road geometry at the curved road sections considering various geometric parameters e.g., radius, length, preceding tangent, deflection angle. The developed models seldomly take into account the operating speed profiles of motorcycle riders and hence no significant efforts have been put so far to associate the geometric characteristics of a road segment with the speed behavior of motorcycle riders. The dominance of 4-wheel vehicles on the road network led the researchers to focus explicitly on the development of speed prediction models for passenger cars, vans, pickups, and trucks. However, although the motorcycle fleet represents only a small proportion of the total traffic volume motorcycle riders are over-represented in traffic accidents especially those that occur on horizontal curves. Since operating speed has been thoroughly documented as the most significant precipitating factor of vehicular accidents, the study of motorcycle rider's speed behavior approaching horizontal curves is of paramount importance. The subject of the present paper is the development of speed prediction models for motorcycle riders traveling on two-lane rural roads. The model was the result of the execution of field measurements under naturalistic conditions with the use of an instrumented motorcycle conducted by experienced motorcycle riders under different lighting conditions. The implemented methodology to determine the most efficient model evaluates a series of road geometry parameters through a comprehensive literature review excluding those with an insignificant impact to the magnitude of the operating speeds in order to establish simple and handy models.

Acceleration characteristics of starting vehicles are needed for many transportation analysis and design purposes involving driveways, turning bays, intersecting streets, traffic signals, railroad crossings, simulation software, and so forth. Constant acceleration is sometimes assumed, or AASHTO Green Book values based on piecewise-constant accelerations are sometimes adopted. However, continuing research has shown that linearly decreasing acceleration rates better represent both maximum vehicle acceleration capabilities and actual motorist behavior. It is not acceleration that usually is constant during speed changes; it is the rate of change in acceleration. The evolution of AASHTO acceleration values for design is traced, and the literature is reviewed for pertinent field observations. Linearly decreasing acceleration (and some deceleration) model parameters are calibrated for various sets of observational and design data. Despite published results from thousands of field measurements, the values selected for design were found to be based mostly on vehicle performance capabilities, with conjecture about how many of these capabilities are normally used by drivers. Design accelerations were found to deviate substantially from observed accelerations. At the start of motion, observed accelerations were about 15 percent faster for passenger cars and 45 percent faster for SU (single unit) trucks than design accelerations. As speed increased, observed accelerations dropped three to four times faster than design accelerations for these vehicles. Observed accelerations for WB-15 trucks began 40 percent to 75 percent slower than design accelerations, and they were considerably slower than the values in the Green Book for trucks at railroad crossings. Voids in the available information base are identified. Linearly decreasing design acceleration rates for motorists operating different classes of vehicles in different design situations are recommended, and revisions for Green Book parameters and charts are suggested. The recommended acceleration model greatly simplifies acceleration parameters but implies using different acceleration relationships for different design speeds instead of one for all.

Drivers adapt their driving to the conditions that they find. When the design corresponds to what a driver hopes to find, the route is consistent. This diminishes the likelihood of drivers making errors and carrying out uncertain manoeuvres. Most evaluations of highway geometric design consistency are based on the analysis of vehicles' speeds. This study reviewed the main models of operating speed prediction on two-lane rural highways. Models calibrated in several countries have been compared by means of their application to the study of nine highway sections located in different terrain types. Also, field measurements have been included in the comparison. The research results show the strengths and weaknesses of those models, their similarities, differences and the lack of suitability of some of them for mountainous highways. Based on them, specific recommendations about which models would be suitable for use are included. The speed profiles predicted by the Spanish model show, in general, higher values than most models calibrated in other countries.

Framework to manage railway noise exposure in Brazil based on field measurements and strategic noise mapping at the local level

Evaluation and prediction method of railway passenger long-term vibration comfort under complex operating conditions

Bandung is the largest metropolitan city in West Java Province and serves as its provincial capital. One of the locations where vehicle queues or traffic congestion occurs is at the level crossings between the highway and railway tracks, including the direct crossing (JPL) at Andir on LMU Nurtanio Street - Abdul Rahman Saleh Street. The purpose of this research is to assess the performance of the existing road section, simulate it using the PTV VISSIM program, and find alternative solutions to the identified problems. In this study, primary data was obtained through direct field measurements, including vehicle volume, queue length, and road geometry data. Additionally, secondary data on the number of trains passing through the crossing was obtained from PT Kereta Indonesian Fire. The PTV VISSIM program used in this analysis is a student-licensed program, which implies limitations and simplifications in the analysis. The performance calculation of the road section yielded a degree of saturation (Ds) value of 0.73 for LMU Nurtanio Street and 0.77 for Abdul Rahman Saleh Street. According to the road service levels set by the government, both roads fall below service level C. The PTV VISSIM modeling results indicated a queue length of 66.59 m for LMU Nurtanio Street and 105.18 m for Abdul Rahman Saleh Street. Bandung study uses PTV VISSIM to assess LMU Nurtanio - Abdul Rahman Saleh Streets, revealing congestion issues. Queue lengths highlight improvement needs.

Abstract. The importance of research into clean and renewable energy solutions has increased over the last decade. Geothermal energy provision is proven to meet both conditions. Therefore, conceptual models for deep geothermal applications were developed for different field sites regarding different local conditions. In Bavaria, Germany, geothermal applications were successfully carried out in carbonate horizons at depths of 4000 to 6000 m. Matrix permeability and thermal conductivity was mainly studied in karstified carbonates from the Late Jurassic reef facies. Similar to Bavaria, carbonates are located in the east of the Rhenohercynian Massif, in North Rhine-Westphalia (NRW), for which quantification of the geothermal potential is still lacking. Compared to Bavaria, a supraregional carbonate mountain belt is exposed at the Remscheid-Altena anticline (in NRW) from the Upper Devonian and Lower Carboniferous times. The aim of our study was to examine the potential geothermal reservoir by field and laboratory investigations. Therefore, three representative outcrops in Wuppertal, Hagen-Hohenlimburg, and Hönnetal were studied. During field surveys, 1068 discontinuities (139 open fractures without any filling, 213 joints, 413 veins filled with calcite, and 303 fractures filled with debris deposits) at various spatial scales were observed by scanline surveys. These discontinuities were characterized by trace length, true spacing, roughness, aperture, and filling materials. Discontinuity orientation analysis indicated three dominant strike orientations in NNW–SSE, NW–SE, and NE–SW directions within the target horizon of interest. This compacted limestone layer (Massenkalk) is approximately 150 m thick and located at 4000 to 6000 m depth, dipping northwards at a dip angle of about 30 to 40∘. An extrapolation of the measured layer orientation and dip suggests that the carbonate reservoir could hypothetically extend below Essen, Bochum, and Dortmund. Our combined analysis of the field and laboratory results has shown that it could be a naturally fractured carbonate reservoir. We evaluated the potential discontinuity network in the reservoir and its orientation with respect to the prevailing maximum horizontal stress before concluding with implications for fluid flow: we proposed focusing on prominent discontinuities striking NNW–SSE for upcoming geothermal applications, as these (1) are the most common, (2) strike in the direction of the main horizontal stress, (3) have a discontinuity permeability that significantly exceeds that of the reservoir rock matrix, and (4) only about 38 % of these discontinuities were observed with a calcite filling. The remaining discontinuities either showed no filling material or showed debris deposits, which we interpret as open at reservoir depth. Our results indicate that even higher permeability can be expected for karstified formations related to the reef facies and hydrothermal processes. Our compiled data set, consisting of laboratory and field measurements, may provide a good basis for 3D subsurface modelling and numerical prediction of fluid flow in the naturally fractured carbonate reservoir.

Field measurements and laboratory investigations were performed on an impermeable dike and the corresponding shallow foreshore. At this site storm conditions and wave run-up levels were measured by Rijkswaterstaat. Two-dimensional physical model tests were performed by WL | Delft Hydraulics and three-dimensional physical model tests were performed by University College Cork. The match between the laboratory tests and the field measurements appeared to be rather good. The three series of measurements also contributed to a prediction method for wave run-up on dikes.

In the deserts of Kuwait in general and in Al-Salmi area in particular, soil compaction and sealing are the most significant mechanisms of land degradation. In the present study, soil compaction and sealing in the Al-Salmi area are assessed. The study is based on analysis of satellite images and aerial photographs, besides field measurements and laboratory investigations. Based on this study, a recent map is prepared for the concerned area. It shows three different soil classes. These are highly compacted (8\8 per cent), slightly compacted (1\7 per cent), and almost non-compacted or natural (89\5 per cent). Soil compaction in Al-Salmi area causes adverse changes in soil physical properties, e.g. infiltration rate, bulk density and soil strength. The infiltration capacity of the compacted soils has decreased by 18\46 to 91\96 per cent in comparison with non-compacted soils. The bulk density for the compacted soil varies between 1\6 and 1\7 g cm−3, whereas it varies between 1\2 and 1\35 g cm−3 in the non-compacted soils, that is an increased of 29\97 per cent. In some sites, the physical properties show small or no difference between compacted and natural soils due to the effect of soil sealing (crustation). Copyright © 2000 John Wiley & Sons, Ltd.

Mitigation of vibrations in high-speed railway cuttings using expanded-polystyrene blocks

After most operators quit using Pin connector, Riser and Diverter for safety reasons, when drilling the tophole section of subsea wells, the use of seawater and sacrificial mud with return to seafloor has to date been the only available practical method. The development of AGR's Riserless Mud Recovery System (RMR) enables drilling the tophole section using weighted inhibited drilling mud. Hence, a number of benefits, such as: Improved hole stability, reduced wash outs, improved well control both with regard to shallow gas and shallow water flow are obtained. Also clay and sand deposits from the boreholes on subsea production templates are prevented. A Demo 2000 project to qualify the RMR System was therefore approved and a Joint Industry project (JIP) was established funded by the Norwegian Research Counsel, Hydro, Statoil and AGR. The JIP was established to qualify the RMR technology for use in 450 meters of water depth. The Demo 2000 project objective was to enable drilling tophole sections collecting returns subsea, and returning to surface in a closed system. A Suction Module with a low pressure rotating control head was installed on the template. This Suction Module collected and diverted the well return into a subsea mud pump lifting the stream of mud and cuttings to the rig processing system. The RMR spread was run through the moon pool on a single derrick rig, and guided and stabilized by a heave compensated guide wire extending to a subsea anchor. Ref. System Schematic, Fig 1. The equipment was engineered and manufactured within an 8-month period, and the field trial took place in December 2004. The paper also discusses the fluid system used, the operational benefits and limitations by applying the RMR technology. Introduction Most operators have abandoned the use of Pin Connector, Riser and Diverter when drilling surface holes for both safety and operational reasons. Especially when drilling deep-water wells, using seawater and gel sweeps being dumped on the seafloor has to date been the only viable solution. In production drilling this has led to the use of Cutting Transport Systems (CTS) or subsea ejector pumps to remove the well returns to a distance from the subsea templates. To allow the use of weighted and inhibited mud for improved bore hole stability, well control and preventing the drill cuttings and cement returns to be dumped on the subsea template and or seafloor, AGR developed a Tophole Drilling Package named RMR - Riserless Mud Recovery System. A Pre- Engineering phase was completed in 2002. This served as basis for establishing the design basis and defining the scope of work when applying for Demo 2000 funding in 2003, to demonstrate and qualify The RMR system for 450 meter water depth by offshore field testing. At the same time as the RMR Demo 2000 project was initiated, AGR was requested to design and build a Riserless Mud Recovery System for BP to be tested on the West Azeri field in The Caspian Sea.

The main aim of the thesis is to investigate the technical feasibility of a new concept in coal mine washery waste disposal, namely INTEGRATED COAL MINE WASHERY WASTE DISPOSAL, and to establish a basis for the proper understanding of the physical phenomena involved in this method. The objective was achieved through various stages such as information gathering, small scale field trials, laboratory modelling and testing, and numerical modelling.Small scale field trials of tailings disposal within a coarse reject embankment conducted at New Hope Colliery, helped to identify the key areas for further laboratory modelling and investigation. The laboratory modelling and testing generated a large amount of information on the engineering behaviour of coal tailings, coarse reject and mixtures of tailings and coarse reject. Subsequent numerical studies illuminated the nature of the seepage of tailings through a coarse reject embankment, and the critical factors controlling it.The consolidation of conventional tailings deposits require excessively long period of time, delaying or prohibiting altogether land rehabilitation work of the tailings storage areas. On the other hand, loosely dumped coarse reject are sources of both air and water pollution, aided by their potential for spontaneous combustion and leaching by rain water infiltration, respectively. Integrated coal washery waste disposal has the potential to ease this situation by eliminating the need for separate disposal areas for tailings and coarse reject. The combined coal washery waste formed by this method is simply a mixture of tailings and coarse reject with many improved engineering properties.Limitations of the conventional laboratory permeability testing equipment with regard to coal mine washery rejects, led to the development of a large diameter constant head permeability testing equipment with additional facilities to consolidate samples to required stress levels. The permeability test carried out in this apparatus clearly demonstrated that, the chief advantage of mixing coarse reject with tailings is the increased permeability of the resultant mixture. An increase in permeability of three to four orders of magnitude (from 10-7 m.s-1 for tailings to 10-3 m.s-1 for mixtures) were recorded from these tests.Consolidation tests carried out in large diameter Rowe cell demonstrated an improved consolidation behaviour for the tailings/coarse reject mixtures. This improvement is mainly attributable to the increased permeability of the mixtures in comparison to tailings only. As the proportion of tailings in a mixture increased (beyond 60% by weight) the mixture started to behave more like tailings. However, the mixture clearly demonstrated improved behaviour over a wide range of tailings to coarse reject mixing ratios (e.g. 20:80 to 40:60).Laboratory seepage modelling tests conducted in a specially designed seepage tank provided sufficient information regarding the filter cake formation and its effect in limiting the seepage through a coarse reject embankment. The transient nature of the seepage, the decreasing solids concentration of the effluent with the passage of time, and the depression of the wetting up line were studied in detail during these model tests.Laboratory tailings/coarse reject mixing trials were conducted in purpose built mixing tank with pore water pressure monitoring facilities. The mixing trials indicated that, to achieve good mixing of tailings and coarse reject, the coarse reject should be introduced into tailings within a certain time period after the deposition of tailings. Early introduction of coarse reject results in segregation, by coarse reject sinking to the bottom of the tailings. Late introduction of the coarse reject again results in segregation, where coarse reject is supported by the tailings, which gain strength by consolidation. Tailings can also be introduced into loose coarse reject, but effective mixing will occur to only shallow depth (of the order of 0.3 m).Consolidated drained direct shear tests carried out on tailings, coarse reject and mixtures thereof clearly indicated that these are essentially frictional materials, and the angle of friction is not very sensitive to the mixing ratios. The angle of friction remained high (above 30°) in all the tests.An existing finite element transient seepage analysis program TSEEP was calibrated using results from the laboratory seepage model tests and soil suction tests. The calibrated program was used to predict the field tailings seepage rate through a coarse reject embankment, simulating the small scale field trials conducted at the initial stages of the thesis investigation. Close agreement was found between the numerical predictions and the field measurements. The effect of the preferred seepage paths on the tailings seepage rate was successfully accounted for in the numerical modelling.The effectiveness of integrated coal washery waste disposal in a full scale mining operation was checked by field investigation carried out on a co-disposal site at Jeebropilly Colliery. The field investigation identified a few problems and the possible means of correcting these shortcomings are discussed in the thesis.

Stray current interference from metro rail transit systems, in the absence of effective mitigation measures, presents a significant challenge to underground pipeline networks, compromising structural integrity. While stray current interference is common in metro rail systems, sudden and severe interference was observed in a pipeline network in Middle East. This was caused by an issue with Platform Screen Doors (PSDs), where the metro was operated with the Overvoltage Protection Device (OVPD) manually activated for safety reasons. This configuration inadvertently connected the metro rails to the Traction Power System (TPS) earth, contrary to the designed insulation. The identification of the root cause of the sudden increase in interference was a challenge, but field measurements, data analysis and simulation techniques were employed to pinpoint the source, quantify the severity of interference and assess its impact on pipeline integrity. The findings highlight the need for routine monitoring, trouble shooting, if any and corrective measures to ensure long-term pipeline reliability and effective corrosion control.

The paper presents the results of field and laboratory investigations carried out on two test embankments located on soft soils in north-western Poland. Comprehensive investigations including observations of test embankments and laboratory testing have been conducted in order to study the behaviour of the consolidation process in soft subsoil. This paper presents the analysis of factors determining the assessment of the deformation process of soft subsoil. The analysis was focused on determining non-linear deformation-stress characteristics used for modelling the deformation of soft subsoil under the earth structure. Deformation characteristics obtained in laboratory tests were compared with field measurements, which included vertical and horizontal displacements, as well as pore pressure dissipation. Based on analysis of field observations and laboratory tests results, the characteristics determining the consolidation process were elaborated.