372 resultados para Concrete bridges.


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Various industrial by-products, such as fly ash, ground granulated blast-furnace slag and silica fume, have been used in concrete to improve its properties. This also enables any environmental issues associated with their disposal. Another material that is available in large quantities and requiring alternative methods of disposal is the Bauxite Refinery Reside (BRR) from the Bayer process used to extract alumina from bauxite. As this is highly caustic and causes many health hazards, Virotec International Ltd. developed a patented technology to convert this into a material that can be used commercially, known as Bauxsolâ„¢, for various environmental remediation applications. This use is limited to small quantities of seawater-neutralised BRR and hence an investigation was carried out to establish its potential utilisation as a sand replacement material in concrete. In addition to fresh properties of concrete containing seawater-neutralised BRR up to 20% by mass of Portland cement, mechanical and durability properties were determined. These properties indicated that seawater-neutralised BRR can be used to replace natural sand up to 10% by mass of cement to improve the durability properties of concrete without detrimentally affecting their physical properties. Combining these beneficial effects with environmental remediation applications, it can be concluded that there are specific applications where concretes containing seawater-neutralised BRR could be used.

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This paper is based on research into the transition of young people leaving public care in Romania. Using this specific country example, the paper aims to contribute to present understandings of the psycho-social transition of young people from care to independent living by introducing the use of Bridges (2002) to build on existing theories and literature. The research discussed involved mixed methods design and was implemented in three phases: semi-structured interviews with 34 care leavers, focus groups with 32 professionals, and a professional-service user working group. The overall findings confirmed that young people experience two different, but interconnected transitions - social and psychological - which take place at different paces. A number of theoretical perpectives are explored to make sense of this transition including attachment theory, focal theory and identity. In addition, a new model for understanding the complex process of transitions was adapted from Bridges’ (2002) to capture the clear complexity of transition which the findings demonstrated in terms of their psycho-social transition. The paper concludes with messages for leaving and after care services with an emphasis on managing the psycho-social transition from care to independent living.

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Much of the thinking about the appropriate ‘political economy’ to underpin sustainable development has been either utopian (as in some ‘green’ political views) or ‘business as usual’ approaches. This article suggests that ‘ecological modernisation’ is the dominant conceptualisation of ‘sustainable development’ within the UK and other ‘developed’ Northern polities and most corporate/business interests, and illustrates this by looking at some key ‘sustainable development’ policy documents from the UK Government. While critical of the reformist ‘policy telos’ of ecological modernisation, supporters of a more radical version of sustainable development need to also be aware of the strategic opportunities of this policy discourse. In particular, the article suggests that the discourse of ‘economic security’, which can be attached to a radicalised notion of ecological modernisation, ought to be used as a way of articulating a radical, robust and principled understanding of sustainable development, which offers a normatively compelling and policy-relevant path to outlining aspects of a ‘green political economy’ to underpin sustainable development.

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