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In this study, a railway superstructure is modeled with a new approach called locally continuous supporting, and its behavior under the effect of moving load is analyzed by using analytical and numerical techniques. The purpose of the study is to demonstrate the success of the new modeling technique.

In the railway superstructure, the support zones are not modeled with discrete spring-damping elements. Instead of this, it is considered to be a continuous viscoelastic structure in the local areas. To model this approach, the governing partial differential equations are derived by Hamilton’s principle and spatially discretized by the Galerkin’s method, and the time integration of the resulting ordinary differential equation system is carried out by the Newmark–Beta method.

Both the proposed model and the solution technique are verified against conventional one-dimensional and three-dimensional finite element models for a specific case, and a very good agreement between the results is observed. The effects of geometric, structural, and loading parameters such as rail-pad length, rail-pad stiffness, rail-pad damping ratio, the gap between rail pads and vehicle speed on the dynamic response of railway superstructure are investigated in detail.

There are mainly two approaches to the modeling of rail pads. The first approach considers them as a single spring-damper connected in parallel located at the centroid of the rail pad. The second one divides the rail pad into several parts, with each of part represented by an equivalent spring-damper system. To obtain realistic results with minimum CPU time for the dynamic response of railway superstructure, the rail pads are modeled as continuous linearly viscoelastic local supports. The mechanical model of viscoelastic material is considered as a spring and damper connected in parallel.

The main objective of the present research is to investigate the benefits of using geogrid reinforcement in minimizing the rate of deterioration of ballasted rail track geometry resting on soft clay and to explore the effect of load amplitude, load frequency, presence of geogrid layer in ballast layer and ballast layer thickness on the behavior of track system. These variables are studied both experimentally and numerically. This paper examines the effect of geogrid reinforced ballast laying on a layer of clayey soil as a subgrade layer, where a half full scale railway tests are conducted as well as a theoretical analysis is performed.

The experimental tests work consists of laboratory model tests to investigate the reduction in the compressibility and stress distribution induced in soft clay under a ballast railway reinforced by geogrid reinforcement subjected to dynamic load. Experimental model based on an approximate half scale for general rail track engineering practice is adopted in this study which is used in Iraqi railways. The investigated parameters are load amplitude, load frequency and presence of geogrid reinforcement layer. A half full-scale railway was constructed for carrying out the tests, which consists of two rails 800 mm in length with three wooden sleepers (900 mm × 90 mm × 90 mm). The ballast was overlying 500 mm thick clay layer. The tests were carried out with and without geogrid reinforcement, the tests were carried out in a well tied steel box of 1.5 m length × 1 m width × 1 m height. A series of laboratory tests were conducted to investigate the response of the ballast and the clay layers where the ballast was reinforced by a geogrid. Settlement in ballast and clay, was measured in reinforced and unreinforced ballast cases. In addition to the laboratory tests, the application of numerical analysis was made by using the finite element program PLAXIS 3D 2013.

It was concluded that the settlement increased with increasing the simulated train load amplitude, there is a sharp increase in settlement up to the cycle 500 and after that, there is a gradual increase to level out between, 2,500 and 4,500 cycles depending on the load frequency. There is a little increase in the induced settlement when the load amplitude increased from 0.5 to 1 ton, but it is higher when the load amplitude increased to 2 ton, the increase in settlement depends on the geogrid existence and the other studied parameters. Both experimental and numerical results showed the same behavior. The effect of load frequency on the settlement ratio is almost constant after 500 cycles. In general, for reinforced cases, the effect of load frequency on the settlement ratio is very small ranging between 0.5 and 2% compared with the unreinforced case.

Increasing the ballast layer thickness from 20 cm to 30 cm leads to decrease the settlement by about 50%. This ascertains the efficiency of ballast in spreading the waves induced by the track.

The railway track system is the platform by which loads from moving trains are transferred to the underlying soil or supporting infrastructure such as bridges. The most common type of railway track system is ballasted track, which has been in use for over a century. Ballasted track has proved versatile. It can be constructed using locally available materials and with modifications to the rails and sleepers, crossings transferring trains from one route to another can be created. The structure of a ballasted track system consists of two main parts. The upper portion, termed the superstructure, comprises the rails, fastenings and sleepers. It is formed of components whose shape, stiffness and strength are designed and closely controlled. Below the superstructure is the substructure, which comprises the ballast and sub-ballast. Although the materials used in the substructure may have been specified, their engineering properties and geometric placement are less well controlled. In this chapter, we will explore how a typical ballasted track system transfers load to the ground and the ways in which the track form deteriorates, requiring maintenance and eventually renewal.

The purpose of this paper is to demonstrate the potential of making the systems approach fertile for the future of our world(s).

Underpinned by a significant case study, the idea of the paper is to show how a systems study changed the basis for deciding on an incisive interference planned for a lovely alpine valley. The study builds on a qualitative conceptual model and reverts to a quantitative, system‐dynamics simulation model, as well as standard economic evaluation methods. The decision process is explained with its outcomes and implications.

The study found, among others, the following concrete result: The optimal variant (Case B) required an additional investment for its realization. According to the calculations that were carried out, the period needed for the amortization of the pertinent amount was found to be no more than 0.9 to 1.6 years. It became clear that the most expensive variant was indeed a very good business proposition for the Austrian Republic.

The results of the study were integrated into the General Traffic Plan of the Austrian Ministry of Transportation, Innovation and Technology, i.e. the study's conclusions obtained legal status. This meant a shift toward a long‐term orientation. In addition, new insights for the realization of similar studies and interventions were gained.

The study described in the paper shows both rigor and relevance. It illuminates a methodology that combines the qualitative and the quantitative, as well as careful analysis and powerful synthesis. Beyond the methods and procedures used in the inquiry, its outcomes and impact on the concrete system under study are demonstrated.

In this study, a finite element model of a box-girder bridge along with the railway sub-track system is developed to predict the static behavior due to different combinations of the Indian railway system and free vibration responses resulting in different natural frequencies and their corresponding mode shapes.

The modeling and evaluation of the bridge and sub-track system were performed using non-closed form finite element method (FEM)-based ANSYS software.

From the analysis, the worst possible cases of deformation and stress due to different static load combinations were determined in the static analysis, while different natural frequencies were determined in the free vibrational analysis that can be used for further analysis because of the dynamic effect of the train vehicle.

The scope of the current investigation is confined to the structure's static and free vibration analysis. However, this study will help the designers obtain relevant information for further analysis of the dynamic behavior of the bridge model.

In static analysis, the maximum deformation of the bridge deck was found to be 10.70E-03m due to load combination 5, whereas the maximum natural frequency for free vibration analysis is found to be 4.7626 Hz.

This chapter begins by outlining the ‘theory’ behind the achievement of a financially sustainable railway, before then examining the realities faced when implementing that theory. This is from the context of the main railway financial outgoings and sources of revenue in both the short- and long-term time horizons. What it suggests is that attainment of such a position has proved to be extremely difficult in practice, with the main reasons for such difficulties outlined and discussed. What is clear, however, is that any such initiatives revolve around the establishment of rigid and robust regulatory and organisational structures that create and maintain a clear separation between state and railway, strongly supported by the ideas of rail financing and rail funding.

Swivel construction is a new bridge construction method, which can minimize the impact on railway and highway traffic. Previous studies were based on single factor and static analysis, which cannot reflect the real state of structures. The purpose of this paper is to establish a dynamic model of the structure and to analyze the situation under multi-variable coupling effects to accurately simulate the real state of the structure.

Finite element software ANSYS was used to establish dynamic model of turntable structure and then to analyze the effects of multiple factors on total stress, friction stress and slipping distance of the turntable structure.

It is concluded that the unbalanced weight and radius of spherical hinges have great influence on the turntable structure, so the design should be strictly considered. Friction stress and angular acceleration have little effect on the turntable structure.

This paper provides simulation of the whole process of swivel construction method. Whereas previous studies focused on static analysis, this paper focuses on the dynamic analysis of swivel construction method. The mechanics of the swivel structure under multiple factors was analyzed. According to the analysis results, the design parameters of the turntable structure are optimized.

The wild boom and slump of 1845‐1847 was the most important of the nineteenth century railway manias, in terms both of its scale and effects on the economy as a whole. It has almost invariably been seen as a market irrationality, a view fundamentally challenged by Bryer’s theorisation of it as a deliberate and collusive device of the “London wealthy”, aided by central government, to swindle provincial middle class investors. This analysis also greatly extended previous perspectives on the rôle of accounting by asserting that accounting practices were crucial to the success of the process and were thus “deeply implicated” in a great, class‐based swindle. The acceptance of such a perspective would have important implications for the way we understand the functioning of accounting and capitalism in the mid‐nineteenth century, but this paper instead argues that such notions are misconceived, looking to both the evidence that was available when Bryer’s paper was written and to recently collected data on the depreciation accounting practices of the time.

With the view of obtaining reliable first‐hand information as to the nature and efficacy of the food laws in Great Britain, France, and Germany, Mr. ROBERT ALLEN, the Secretary of the Pure Food Commission of Kentucky, has recently visited London, Paris, and Berlin. He has now published a report, containing a number of facts and conclusions of very considerable interest and importance, which, we presume, will be laid before the great Congress of Food Experts to be held on the occasion of the forthcoming exposition at St. Louis. Mr. ALLEN severely criticises the British system, and calls particular attention to the evils attending our feeble legislation, and still more feeble administrative methods. The criticisms are severe, but they are just. Great Britain, says Mr. ALLEN, is par excellence the dumping‐ground for adulterated, sophisticated, and impoverished foods of all kinds. France, Germany, and America, he observes, have added a superstructure to their Tariff walls in the shape of standards of purity for imported food‐products, while through Great Britain's open door are thrust the greater part of the bad goods which would be now rejected in the three countries above referred to. Whatever views may be held as to the imposition of Tariffs no sane person will deny the importance of instituting some kind of effective control over the quality of imported food products, and, while it may be admitted that an attempt—all too restricted in its nature—has been made in the Food Act of 1899 to deal with the matter, it certainly cannot be said that any really effective official control of the kind indicated is at present in existence in the British Isles. We agree with Mr. ALLEN'S statement that our food laws are inadequate and that, such as they are, those laws are poorly enforced, or not enforced at all. It is also true that there are no “standards” or “limits” in regard to the composition and quality of food products “except loose and low standards for butter and milk,” and we are compelled to admit that with the exception of the British Analytical Control there exists no organisation—either official or voluntary —which can be said to concern itself in a comprehensive and effective manner with the all‐important subject of the nature and quality of the food supply of the people. In the United States, and in some of those European countries which are entitled to call themselves civilised, the pure food question has been studied carefully and seriously in recent years—with the result that legislation and administrative machinery of far superior types to ours are rapidly being introduced. With us adulteration, sophistication, and the supply of inferior goods are still commonly regarded as matters to be treated in a sort of joking spirit, even by persons whose education and position are such as to make their adoption of so foolish an attitude most astonishing to those who have given even but slight attention to the subject. Lethargy, carelessness, and a species of feeble frivolity appear to be growing among us to such an extent as to threaten to become dangerous in a national sense. We should be thankful for outspoken criticism—if only for the bracing effect it ought to produce.

Commenting on the Mexican Revolution in 1938, Trotsky argued that the country might achieve “national independence,” understood as a break with dependency relations. Whether this might occur depended – Trotsky continued – on “international factors.” Though not engaging with Mexico, Antonio Gramsci made a similar theoretical point. It is hence from this perspective that this chapter analyses the Mexican Revolution, asking whether it led to a break in dependency relations and the attainment of “national independence” or what I refer to as “relative geopolitical autonomy.” Presenting a framework of analysis largely based on the work of Gramsci that highlights its continuity with the thought of Marx, the chapter will answer negatively to this question. The chapter starts from the idea that Porfirio Díaz’s regime was unable to adapt the economic structure (still pre-capitalist) to the complex superstructures (capitalist), that is, to realize an historic bloc. It would be this job that the emergent Mexican bourgeoisie sought to finish. However, the situation is complicated by the powerful emergence of social movements from below, constituted largely by landless peasants, and to a lesser extent, the industrial proletariat. I will therefore argue that the revolution has been both “passive” and “bounded.” The term passive revolution will be applied to the last phase of the revolution as the emerging bourgeoisie successfully coopted the demands of the popular masses thereby “passivizing” them. But crucially, the revolution was also “bounded” because international factors, and especially US influence, played a conditioning role throughout the revolutionary process. At the same time, it would be the very “passive” nature of the revolution that would contribute to the reproduction of relations of dependency. Hence the chapter concludes that the period Trotsky commented upon (the Cárdenas period) is the highest level of “independence” Mexico achieved, only to decrease again over the years.