Loading Gauge Research Articles

Effects of rail network enhancement on port hinterland container activity: a United Kingdom case study

Transport infrastructure investment is an important element in the creation of an efficient and sustainable transport sector. Intermodal flows are seen as critical to rail freight’s future success and feature strongly in contemporary transport policy. This paper investigates a practical rail network enhancement scheme from the United Kingdom (UK) designed to achieve a shift of containers from road to rail. The paper’s aim is to determine the effects on rail freight efficiency of a loading gauge increase in April 2011 which allowed 9′ 6″ high containers to be transported on standard wagons on the corridor from the port of Southampton to the West Midlands. The study is based on a “before and after” survey of container train capacity provision and load factors, with the “before” survey taking place in 2007 and the “after” survey in 2012. A consistent approach to data collection in both surveys allows detailed analysis of original survey data to be carried out. It is clear that there have been considerable improvements in both on-train capacity and train loads between 2007 and 2012, and that these improvements have been greatest on routes that have benefited from the gauge enhancement. Rail’s mode share of container throughput at Southampton has increased. There have also been wider benefits to off-corridor locations served from Southampton and elsewhere across the network. Overall, the impacts on rail freight efficiency of the gauge enhancement have been substantial, with efficiency improvements evident even at a time of economic stagnation.

Fatigue performance and fatigue damage parameter estimation of spot welded joints of aluminium alloys 6111‐T4 and 5754

ABSTRACTIn the present study, fatigue behaviours of spot welded joints of aluminium alloys 6111‐T4 and 5754 have been experimentally investigated. Fatigue results indicate that fatigue strength of spot weld primarily depends on specimen loading type and gauge thickness. Effects of base material and load ratio on fatigue resistance of welded specimen are insignificant. An equivalent stress based fatigue damage parameter is derived to consolidate empirical data and develop predictive capabilities for automobile designers. The fatigue damage parameter defined in this study is proven effective in consolidating a large amount of fatigue data into a narrow band and is especially suitable for the comparative fatigue strength evaluation of components and specimens.

An Experimental Study on Ultimate Behaviors of Double Shear Bolted Connections with Ferritic Stainless Steel

Based on the existing test results of single shear bolted connection fabricated with cold-formed ferritic stainless steel, in this study, the experiment for double shear bolted connections with bolt arrangements(1×2, 2×2) and end distance parallel to the loading direction as main variables has been performed. Specimens were planed with a constant dimension of edge distance perpendicular to the loading direction, bolt diameter, pitch and gauge. Ultimate strength and fracture mode obtained from test results were compared with those predicted by current American and Japan design codes such as AISI and AIJ.

Ultimate strength of single shear bolted connections with cold-formed ferritic stainless steel

This paper is focused on the structural behavior of the single shear bolted connections with thin-walled ferritic stainless steel. The purpose of this study is to investigate the ultimate behaviors, such as ultimate strength and fracture mode of the single shear bolted connections of thin-walled ferritic stainless steel (low cost steel) rather than austenitic stainless steel (high cost steel). Bolt arrangement and end distance parallel to the direction of applied load are considered as main variables of the test specimens for bolted connections. Specimens have a constant dimension of edge distance perpendicular to the loading direction, bolt diameter, pitch, and gauge. A monotonic tensile test for specimens has been carried out and some bolted connections with long end distance showed curling (out of plane deformation) occurrence which led to strength reduction. The ultimate behaviors such as fracture mode, ultimate strength are compared with those predicted by current design codes. Further, conditions of curling occurrence and the strength reduction due to curling are investigated and modified strength equations are suggested considering the curling effect.

An Experimental Study on Structural Behaviors of Double Shear Bolted Connections Fabricated with Ferritic Stainless Steel (STS430)

일면전단 오스테나이트계 스테인리스강 및 탄소강에 관한 많은 실험 및 해석적 연구가 수행되어졌고, 수정된 내력평가식이 제안되었다. 본 연구에서는 볼트배열(2행 1열, 2행 2열)과 하중방향 연단거리를 주요변수로 하여 이면전단 볼트접합부 실험체가 제작되었고, 단순인장실험이 실시되었다. 고정변수로는 하중직각방향 연단거리, 볼트직경, 피치, 게이지를 설정하였다. 최대내력과 파단형태와 같은 실험결과와 현행기준식에 의한 예측결과와 비교 검토되었다. 볼트배열에 따른 블록전단내력평가식이 제안되었다. Many experimental and numerical researches for thin-walled carbon steel and austenitic stainless steel single shear bolted connections have been conducted and the modified design equations of ultimate strength were proposed. In this study, the tests of double shear bolted connections with bolt arrangements (<TEX>$2{\times}1$</TEX>, <TEX>$2{\times}2$</TEX>) and end distance parallel to the loading direction as main variables were performed. Specimens were planed with a constant dimension of edge distance perpendicular to the loading direction, bolt diameter, pitch and gauge like single shear bolted connections. The test results such as ultimate strength and fracture mode were compared with those of current design standards. Furthermore, modified block shear equations for double shear bolted connections were suggested.

Modelling progressive failure of fibre reinforced laminated composites: mesh objective calculations

AbstractA thermodynamically-based work potential theory for modelling progressive damage and failure in fibre-reinforced laminates is presented. The current, multiple-internal state variable (ISV) formulation, enhanced Schapery theory, utilises separate ISVs for modelling the effects of damage and failure. Damage is considered to be the effect of any structural changes in a material that manifest as pre-peak non-linearity in the stress versus strain response. Conversely, failure is taken to be the effect of the evolution of any mechanisms that results in post-peak strain softening. It is assumed, matrix microdamage is the dominant damage mechanism in continuous, fibre-reinforced, polymer matrix laminates, and its evolution is captured with a single ISV. Three additional ISVs are introduced to account for failure due to mode I transverse cracking, mode II transverse cracking, and mode I axial failure. Using the stationarity of the total work potential with respect to each ISV, a set of thermodynamically consistent evolution equations for the ISVs is derived. Typically, failure evolution (i.e. post-peak strain softening) results in pathologically mesh dependent solutions within a finite element method numerical setting. Therefore, consistent characteristic element lengths are introduced into the formulation of of the three failure potentials. The theory is implemented into commercial FEM software. The model is verified against experimental results from a laminated, quasi-isotropic, T800/3900-2 panel containing a central notch. Global load versus displacement, global load versus local strain gauge data, and macroscopic failure paths obtained from the models are compared to the experiments. Finally, a sensitivity study is performed on the failure parameters used in the model.

Portland's tri-met light rail system celebrates ten years [Transportation systems

The Norwegian National Railways (NSB) awarded an order for a total of 50 Flinker Leichter Innovativer Regional Triebzug (FLIRT) trains (Figure 1) plus an option for 100 further trains to Stadler Rail in August. This fleet renewal represents the largest order ever placed by the NSB. The order consists of 26 five-car train sets for the S-Rail operation in the Oslo area. An additional 24 train sets will be supplied by Stadler for medium- length routes throughout the whole of Southern Norway up to the area around Bergen. The first train set of 32 FLIRT trains to be used on the 5-ft gauge Helsinki S-Bahn was rolled out of the Stadler plant in Switzerland in October. All windows are triple-glazed and double-thick to cope with the severe winter temperatures that can go down as low as -40 degF. Heaters and warm air blowers are installed at the entrances to keep the cold outside air from entering the cars. The trains being built for Finland are configured in four-car sets with 260 seats. With a loading gauge of ten and a half feet, the three and two seating is expected to be a little more comfortable than the three and two seating common on commuter lines in the Unites States where the loading gauge is ten feet. The trains are designed to operate at speeds up to 100 mi/h. The signaling installed on the trains will be the Bombardier EBICAB standard in Finland, but the design is such that conversion to the new European standard of the European Control and Command System (ETCS) can be easily accomplished in the future.

Experimental evaluation of accuracy of current practices in analysis and design of railway track sleepers

This research investigates the accuracy of the assumptions made in the current method of analysis and design of railway track sleepers. This study consists of a comprehensive field investigation into the response of sleepers in a railway track system to static and dynamic loads. In the experiments, several load cells (load gauges) are installed under a rail seat and beneath a B70 concrete sleeper for the purpose of monitoring the response of the sleeper to vertical loads. The dynamic coefficients factor, the ratio of the rail seat load to the wheel load and the pressures between the sleeper and the ballast are measured. The results are used to evaluate the current approaches for the analysis and design of concrete sleepers, in particular those proposed by the Americans (AREMA) and Europeans (UIC). New models are proposed for the calculation of dynamic load factors, correlations between wheel loads and rail seat loads, and load distribution patterns beneath sleepers.

Making maximum use of restrictive loading gauge as applied to friction damped freight vehicles

The presence of highly non-linear friction damping in the suspensions of many freight vehicles reduces prediction accuracy when using traditional kinematic gauging techniques. These techniques, which are often applied to the more linear behaving passenger vehicles, are based on the quasi-static suspension behaviour. Due to this limitation and a market requirement for cost effective and rapid vehicle gauging, the current approach in the UK for freight vehicles is to use static vehicle gauges. This method can be very conservative and lead to in-efficient use of the available space between vehicle and infrastructure. Computer simulation-based dynamic gauging techniques offer a way to maximize the use of the space available, by introducing into the gauging analysis, the dynamic behaviour of the vehicle. This paper describes the process of dynamic gauging for friction damped freight vehicles. The benefits of this method in terms of potential increase of the vehicle size are shown, but also difficulties within the process, especially concerning the adequate validation of the simulation models.

Strain analysis in MEMS/NEMS structures and devices by using focused ion beam system

Measurement of residual strain/stress in microstructures using a focused ion beam (FIB) moiré technique is demonstrated in this paper. This technique is selected based on advantages of the FIB system in nano-machining, in situ deposition, imaging, and fine adjustment. A nano-grating is directly written on the top of the microstructures by ion milling without any etch mask; the FIB moiré pattern is formed by the interference between a prepared specimen grating and raster scan lines. Effects of milling sequence, grating spacing and trench depth on the nano-grating structures and moiré fringes have been investigated. Strain evolution in microstructures during underlying sacrificial layer etching was studied. The sign of strain was derived from a rotation moiré technique. Moreover, a mass loading gauge with nano-gram resolution has been built. Since the local strain of a microstructure itself can be monitored during the process, the FIB moiré technique has many potential applications in the mechanical metrology of micro/nano-electro-mechanical-systems (MEMS/NEMS).

Validation test for climate control on air-loss supports

Reger SI, Adams TC, Maklebust JA, Sahgal V. Validation test for climate control on air-loss supports. Arch Phys Med Rehabil 2001;82:597-603. Objective: To develop a simple, reproducible validation test protocol for classification of air-loss support systems. Design: Simultaneous experimental measurement of moisture loss and temperature reduction at the air-loss support surface—human body equivalent interface from a sweating human skin analogue. Setting: A hospital department of physical medicine and rehabilitation. Other Participants: These 3 manufacturers contributed 14 support surfaces. Interventions: Test support surfaces and a standard foam mattress were placed on a hospital bed. Water was circulated to a loading gauge, placed on a dry moisture reservoir, and connected to a water bath to keep the interface at 37° ± 0.5° C. The loading gauge and support surface was adjusted 23cm below the water bath level and the air flow through the interface initiated. After the dry moisture reservoir came to temperature equilibrium for 30 minutes, it was replaced with a wet one that was saturated with 36g of saline. The temperature change and evaporation rate were recorded throughout a 90-minute test period. Main Outcome Measures: Temperature of support surface interface and evaporation rate. Results: Clustered data from temperature reduction and standardized rate of moisture loss yielded 3 groups of support surfaces in categories of no air loss (control), low air loss (LAL), and high air loss. The mean values of the characteristic temperature reduction and rate of moisture loss differed significantly between the groups. By multiple comparisons with Bonferroni's adjustment, the group means differed significantly for average temperature reduction (p <.017) and for standardized rate of moisture loss (p =.0001). The measured temperature change at any instant of time reflected the effect of evaporation and the opposing effect of thermal conductivity. Conclusion: Measurements of support interface climate change allowed for selective grouping of LAL surfaces according to rate of moisture evaporation and the resulting temperature reduction. Neither temperature change nor evaporation rate alone was sufficient to determine the microclimate characteristics of the support surface. Combined, these characteristics can effectively describe the performance of any LAL support system and may be used to define standards of performance. © 2001 by the American Congress of Rehabilitation Medicine and the American Academy of Physical Medicine and Rehabilitation

A review of methods to measure and calculate train resistances

This paper discusses a well-known tool for calculating train resistance to motion and its suitability for describing operations at high speed. The tool, originally developed by Armstrong and Swift [1], also permits the estimation of the contribution to aerodynamic resistance of various features of the architecture of a train. They compare this approach with the results of other formulae for calculating train resistance, as well as published measurements taken during experimental work. It is concluded that Armstrong and Swift's expressions can be considered to provide good estimates for the coefficients to the Davis equation for both high-speed and suburban trains that fit the British loading gauge and have a power car-trailer ratio of 1:3 or less without the need for run-down testing. However, the expressions are not suitable for trains with a predominance of powered axles.

On freight wagon dynamics and track deterioration

To increase understanding of the running behaviour of freight wagons a research project was started at the Royal Institute of Technology (KTH) in 1996. The background to the project included plans to increase axle load, loading gauge and speed of freight trains in Sweden to make freight traffic more competitive. Simulation models for three different types of UIC freight wagon running gear were developed. The present paper focuses on track deterioration of freight wagons caused by high vertical wheel-rail forces. First the characteristics and modelling of some suspension elements are described, followed by a description of the deterioration model. Then the influence of the parameters of axle load, height of the centre of gravity and vehicle speed on track deterioration is investigated. Track parameters such as rail type and sleeper spacing are varied. The conclusion is that track deterioration per transported pay load increases when the axle load and loading gauge are increased. However, this can be compensated by using an improved track design.

Channel Tunnel freight services between Scotland and continental Europe: an examination of the opportunities and constraints

Recent research has revealed strong demand among Scottish manufacturers for improved international freight transport links. The development of new Channel Tunnel services will help to meet this demand. International road haulage, which currently handles the majority of Scottish unitized freight, will nevertheless derive relatively little benefit from the tunnel shuttle service. The new through-rail services will provide a much greater opportunity for Scottish exporters. Although not necessarily depressing freight rates, they should be able to offer shorter and more reliable transit times and thus strengthen the competitive position of the high-value, time-sensitive products which account for the majority of Scotland's exports to Europe. The use of small-wheeled rolling stock on these services is likely to be sub-optimal, though, for Scotland, the enlargement of the rail loading gauge only as far as a London or Midlands railhead would prove more problematic. The paper assesses the likely utilization of the through-rail services and confirms, on the basis of new market research, that official forecasts are of the right order of magnitude. Doubt is expressed, however, about the ability of the Eurofreight terminal planned for North Lanarkshire to act as a nucleus for industrial and distribution development. The new Channel Tunnel freight services are likely to have a positive effect on the Scottish economy, though their influence on the volume and pattern of the region's trade with Europe is likely to be modest.

BOA—the RAPT's New Concept for its Urban System

This mini-paper describes the background to the decision of the Régie Autonome des Transports Parisiens (RAPT), the Paris Transport Authority, to develop a new form of rolling stock for operation on the urban Métro network (as opposed to the RER), where car size is severely constrained by a tight loading gauge and extremely sharp curvature. The object was to provide for better passenger distribution throughout a train, coupled with a reduction in overall weight and a reduction of waste space between vehicles, with a consequent increase in the effective passenger capacity.

Investigating the market for inter-modal freight technologies

Freight carried by rail has traditionally been mainly low value bulk commodities. The market for transport of such commodities appears at best static and is forming a smaller proportion of the total demand for freight transport. There is thus an urgent need for rail operators to develop practical and cost effective inter-modal systems, which offer high quality services to consignors of consumer goods whose premises are not usually connected to the rail network. Much long-haul traffic of this type is international. In continental Europe, a number of inter-modal technologies—including swapbodies and piggyback—have long been in use. Development of similar technologies for use within the more constrained loading gauge of Great Britain, has received a great boost from the impending opening of the Channel Tunnel. The alternative technologies are discussed, before turning to ways of stimating the market for them. A large part of the paper is devoted to reporting on a computerised survey using our LASP (Leeds Adaptive Stated Preference) technique. The reason for using hypothetical Stated Preference data is the inadequate nature and extent of data on actual choice decisions, particularly in circumstances in which confidential freight rates are individually negotiated and little general merchandise goes by rail. By bringing together the results of this survey with information on costs and quality of service, the likely future market for inter-modal freight technologies is assessed. It is seen that the potential for inter-modal services within Britain is very limited, although there should be a good opportunity on the major corridor from London to Scotland through the West Midlands and the North West. When the Channel Tunnel is opened, however, the potential for services between Britain and continental Europe will be enormous, provided that an adequate quality of service can be offered.

Significance of pop-in fracture toughness testing

O . • . C J~ r R-curve testlng. Figure l(a) shows the load vs cllp gauge ~isplaceIC ment trace from a CTOD test on a ferritic steel which is in the middle of its transition temperature range. Cleavage fracture is preceded by considerable plasticity and possibly some tearing. Figure l(b) shows a test record from a specimen exhibiting pop-in. A small, rapid drop in load is observed, which is subsequently recovered. There are many possible causes of this load drop [i], but the one of interest here is the initiation and arrest of a cleavage crack.

Measurement of tearing toughness on BS4360:50D structural steel

Toughness was measured and crack growth resistance curves determined on BS4360:50D steel, over a range of orientations and temperatures from + 20 to − 50° C in terms of both J-integral and crack opening displacement (COD) values, for a number of configurations in static bending. All fractures occurred in a ductile micro-mode. The results are discussed here only in terms of J, but several different methods of estimation are used. These fall into two main groups: for measurement of work done, the results are some 10% higher than those determined from load and clip gauge. Values of JIC found according to the standard ASTM method were some 30% higher than a value for no growth. Maximum load toughness was about twice the JIC value. Over the range studied (0.3 < a/W < 0.5; W/2 < B < W; 20 mm < B < 50 mm; Δa/b < 0.1 where a is crack length, W and B specimen width and thickness, and b=W−a) both J and COD values depended strongly on orientation, but J by either type of analysis was invariant with respect to temperature and sensitive to geometry only in respect of thickness in one case. Conditions of testing do not therefore seem at all critical in this regime, although the values found depend on the methods of analysis used.

The theory and design of photoelastic load gauges incorporating glass element transducers

A glass cylinder compressed across a diameter can be used as an effective load transducer by utilizing the birefringent properties of the glass. Calibration of applied load in terms of fringe order can readily be obtained by using a suitable polariscope. Incorporating the basic cylindrical transducer into a steel body greatly extends the load-measuring range, enabling a flexible load-gauge system to be developed. Stresses applied to the glass and steel components are kept to well below their respective elastic limits which, combined with the absence of moving parts, gives tise to gauges of excellent long-term stability. The various factors affecting the design and performance of this type of load gauge are discussed herein. The stress distribution and photoelastic effects within the glass cylinder are considered, together with its mode of deformation under diametral compression. Attention is also directed towards determining the stresses and displacements in various gauge components; in this connexion, an analytical solution is given for the deformation of a circular hole in a uniaxially loaded strip of finite width. A range of theoretical calibration curves for column-type and ring-type gauges is given, and further aspects such as temperature susceptibility and long-term stability are examined. An example of the design and application of a photoelastic load gauge which has been used in practice is also included.

PHOLOELASTIC INSTRUMENTATION IN CIVIL ENGINEERING STRUCTURES

This paper deals with the measurement of stress or load in three structures using photoelastic gauges. Principals of photoelastic gauging are described with reference to the design and installation of a photoelastic stressmeter and gauges to measure earth pressure and steel cable tensions.Applications are described as follows: The measurement of load distribution between a concrete raft and piles using photoelastic stressmeters and photoelastic earth pressure gauges. The measurement of stresses in a prestressed box cantilever bridge using photoelastic stressmeters. The control of tension in the main supporting cables of a large suspension bridge using photoelastic load gauges.