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Performance evaluation of rail trackbed stiffness: pre and post stabilisation
Excessive deflection of a rail in response to axle loading can lead to discomfort for passengers and increased wear of both railway structures and trains. These oscillations are often caused by poor trackbed stiffness which may be due to either soft subgrade and/or contaminated ballast. A variety of trackbed stabilisation (TBS) techniques are available to remediate soft subgrades and increase the safety of tracks within the railway network. Traditional TBS methods require track removal, which is expensive, disruptive and often inefficient maintenance works. Micro-piling, using screw piles installed between sleepers, is an innovative low disruption TBS technique. This paper investigates the performance of a soft subgrade and contaminated ballast section of rail line in the UK, before and after screw pile TBS. Pre and post remediation, a computer vision-based system was used to measure rail vertical deflections during train passages and then analysed to quantify the trackbed stiffness. Additionally, 3D finite element models are created and validated by the site measurements. The finite element models are used to simulate a range of different scenarios exploring how changes to the TBS piling layout and/or further works, such as ballast improvement could add further improvements or design efficiencies. Site measurements show TBS reduced rail deflection by 20â30%, indicating that micro-piling is an effective technique for soft subgrades. The finite element analysis revealed the efficiency of micro-piling is highly dependent on the conditions of ballast, strength of the ground at the pile toe, and the pile arrangement. When the aforementioned are optimised the rail deflection could be reduced to approximately 50% of the pre TBS condition
Democratic cultural policy : democratic forms and policy consequences
The forms that are adopted to give practical meaning to democracy are assessed to identify what their implications are for the production of public policies in general and cultural policies in particular. A comparison of direct, representative, democratic elitist and deliberative versions of democracy identifies clear differences between them in terms of policy form and democratic practice. Further elaboration of these differences and their consequences are identified as areas for further research
A study of the role of a technology-enhanced learning implementation group in mediating an institutional VLE minimum standards policy
Recent years have seen a focus on responding to student expectations in higher education. As a result, a number of technology-enhanced learning (TEL) policies have stipulated a requirement for a minimum virtual learning environment (VLE) standard to provide a consistent student experience. This paper offers insight into an under-researched area of such a VLE standard policy development using a case study of one university. With reference to the implementation staircase model, this study takes cue from the view that an institutional VLE template can affect lower levels directly, sidestepping the chain in the implementation staircase. The Group's activity whose remit is to design and develop a VLE template, therefore, becomes significant. The study, drawing on activity theory, explores the mediating role of such a Group. Factors of success and sources of tension are analysed to understand the interaction between the individuals and the collective agency of Group members. The paper identifies implications to practice for similar TEL development projects. Success factors identified demonstrated the importance of good project management principles, establishing clear rules and division of labour for TEL development groups. One key finding is that Group members are needed to draw on both different and shared mediating artefacts, supporting the conclusion that the nature of the group's composition and the situated expertise of its members are crucial for project success. The paper's theoretical contribution is an enhanced representation of a TEL policy implementation staircase
Fragments of equality in representative politics
Deploying a broadly interpretive approach, the article explores the extent to which, and the ways in which, equality is enacted in non-elective as well as elective representation. It argues that the fleeting and fragmentary equalities evident in non-elective representation are democratically significant, and that examining them can enhance understanding of the democratic promise and limits of different modes of representation
Understanding and Challenging Populist Negativity towards Politics: The Perspectives of British Citizens
This article adapts and develops the idea of a cynical or âstealthâ understanding of politics to
explore how citizensâ estrangement from formal politics is processed cognitively through a
populist lens. Earlier work has shown the widespread presence of stealth attitudes in the United
States and Finland. We show that stealth attitudes are also well established in Britain, demonstrate
their populist character and reveal that age, newspaper readership and concerns about governing
practices help predict their adoption by individuals. Yet our survey findings also reveal a larger
body of positive attitudes towards the practice of democracy suggesting that there is scope for
challenging populist cynicism. We explore these so-called âsunshineâ attitudes and connect them to
the reform options favoured by British citizens. If we are to challenge populist negativity towards
politics, we conclude that improving the operation of representative politics is more important
than offering citizens new forms of more deliberative participation
Europe - a default or a dream? European identity formation among Bulgarian and English children
This is the authors' accepted version of an article published in Ethnicities, 2014. http://online.sagepub.com/10.1177/1468796812465722This article examines the formation of European identity among children in two very different countries: the traditionally Eurosceptic United Kingdom and the enthusiastic EU newcomer, Bulgaria. The paper revisits existing debates about the relationships between European identity, knowledge and the political and historical context, paying particular attention to the meanings attached to Europe. It demonstrates that children who identify as European are more likely to see Europe in geographic terms, which facilitates the perception of the European identity as âdefaultâ. In contrast, children who refuse to describe themselves as European see Europe as an exclusive political entity, associated with high standards and distant elites. These perceptions are significantly more common among Bulgarian children, who often depict Europe as a dream, and perceive the European identity as an ideal they aspire to reach. The article also shows how ethnicity and the images of Europe influence the relationship between national and European identities
Lime Cake as an Alternative Stabiliser for Loose Clayey Loams
Lime Cake (precipitated calcium carbonate PCC), a by-product of sugar production, is proposed as a stabiliser for improvement of loose silty clayey loams. Two inorganic pedogenic and organic precipitated calcium carbonate polymorphs are artificially synthesized into a base loosely compacted loamy soil. Formation, micromorphology, quality of cementing bonds, and physiochemical interactions in the interlayer are modelled at molecular level and verified by a suite of micro-analytical spectrometry techniques. Emphasis is put into determining the impacts of polysaccharides on soil strength and implications on soil pore anatomy. Erodibility, compressibility, volumetric change, and hydro-mechanical behaviour of base, and modified soils at yield and post-yield states are studied. Anomalies in suction-controlled post-yield stressâstrain behaviour of modified soils are discussed and explained within the tenets of mechanics of composite soils with double porosity. PCC-reinforcement offers the closest possible packing at optimum water content. Desiccation cracking remains likely, but at relatively higher lower-bound water contents. Under low confinement levels and unsaturated state, strain-hardening prevails. Loss of shear strength on saturation is minimal. When saturated, PCC-reinforced soil develops substantially high levels of shear strength at all strain levels. Higher levels of confinement are needed for organic fibrous and onion-skin coating matters to effectively encrust the soil pore network; such high levels, however, leads to formation of an unwelcomed brittle, strainâsoftening stressâstress behaviour
Everyday legitimacy and international administration: global governance and local legitimacy in Kosovo
International administrations are a very specific form of statebuilding. This paper examines the limits illustrated by the experience in Kosovo. Here, the international administration faced the same requirements of any legitimate, Liberal government, but without the checks and balances normally associated with Liberal governance. Thus, the international administration was granted full authority and the power thereby associated, but without the legitimacy upon which the Liberal social contract rests. The state-building agenda put forth came to be seen as more exogenous, reinforcing the delegitimization process. This paper will specifically address the influence of the Weberian approach to legitimacy on the statebuilding literature, as well as its limits. It will then propose other possible avenues for statebuilding, more in line with a wider understanding of legitimacy and intervention
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