The performance of stabilized and unstabilized minestone in an aqueous environment with emphasis on its erosion resistance

Britain's sea and flood defences are becoming increasingly aged and as a consequence, more fragile and vulnerable. As the government's philosophy on resources shifts against the use of prime quarried and dredged geo-materials, the need to find alternative bulk materials to bolster Britain's prone defences becomes more pressing. One conceivable source for such a material is colliery waste or minestone. Although a plethora of erosion-abrasion studies have been carried out on soils and soil-cements, very little research has been undertaken to determine the resistance of minestone and its cement stabilized form to the effects of water erosion. The thesis reviews the current extent to which soil-cements, minestone and cement stabilized minestone (CSM) have been employed for hydraulic construction projects. A synopsis is also given on the effects of immersion on shales, mudstones and minestone, especially with regard to the phenomena of slaking. A laboratory study was undertaken featuring a selection of minestones from several British coalfields. The stability of minestone and CSM in sea water and distilled water was assessed using slaking tests and immersion monitoring and the bearing on the use of these materials for hydraulic construction is discussed. Following a review of current erosion apparatus, the erosion/abrasion test and rotating cylinder device were chosen and employed to assess the erosion resistance of minestone and CSM. Comparison was made with a sand mix designed to represent a dredged sand, the more traditional, bulk hydraulic construction material. The results of the erosion study suggest that both minestone and CSM were more resistant to erosion and abrasion than equivalently treated sand mixes. The greater resistance of minestone to the agents of erosion and abrasion is attributed to several factors including the size of the particles, a greater degree of cement bonding and the ability of the minestone aggregate to absorb, rather than transmit shock waves produced by impacting abrasive particles. Although minestone is shown to be highly unstable when subjected to cyclic changes in its moisture content, the study suggests that even in an intertidal regime where cyclic immersion does takes place, minestone will retain sufficient moisture within its fabric to prevent slaking from taking place. The slaking study reveals a close relationship between slaking susceptibility and total pore surface area as revealed by porosimetry. The immersion study shows that although the fabric of CSM is rapidly attacked in sea water, a high degree of the disruption is associated with the edges and corners of samples (ie. free surface) while the integrity of the internal fabric remains relatively intact. CSM samples were shown to be resilient when subjected to immersion in distilled water. An overall assessment of minestone and CSM would suggest that with the implementation of judicious selection and appropriate quality control they could be used as alternative materials for flood and sea defences. It is believed, that even in the harsh regime of a marine environment, CSM could be employed for temporary and sacrificial schemes.

Re-engineering construction communication in distance management framework

In an exploding and fluctuating construction market, managers are facing a challenge, which is how to manage business on a wider scale and to utilize modern developments in information technology to promote productivity. The extraordinary development of telecommunications and computer technology makes it possible for people to plan, lead, control, organize and manage projects from a distance without the need to be on site on a daily basis. A modern management known as distance management (DM) or remote management is emerging. Physical distance no longer determines the boundary of management since managers can now operate projects through virtual teams that organize manpower, material and production without face-to-face communication. What organization prototype could overcome psychological and physical barriers to reengineer a successful project through information technology? What criteria distinguishes the adapted way of communication of individual activities in a teamwork and assist the integration of an efficient and effective communication between face-to-face and a physical distance? The entire methodology has been explained through a case application on refuse incineration plant projects in Taiwan.

The detection and identification of extraneous metals in material conveyance systems

The aim of this work was to design and build an equipment which can detect ferrous and non-ferrous objects in conveyed commodities, discriminate between them and locate the object along the belt and on the width of the belt. The magnetic induction mechanism was used as a means of achieving the objectives of this research. In order to choose the appropriate geometry and size of the induction field source, the field distributions of different source geometries and sizes were studied in detail. From these investigations it was found the square loop geometry is the most appropriate as a field generating source for the purpose of this project. The phenomena of field distribution in the conductors was also investigated. An equipment was designed and built at the preliminary stages of thework based on a flux-gate magnetometer with the ability to detect only ferrous objects.The instrument was designed such that it could be used to detect ferrous objects in the coal conveyors of power stations. The advantages of employing this detector in the power industry over the present ferrous metal electromagnetic separators were also considered. The objectives of this project culminated in the design and construction of a ferrous and non-ferrous detector with the ability to discriminate between ferrous and non-ferrous metals and to locate the objects on the conveying system. An experimental study was carried out to test the performance of the equipment in the detection of ferrous and non-ferrous objects of a given size carried on the conveyor belt. The ability of the equipment to discriminate between the types of metals and to locate the object on the belt was also evaluated experimentally. The benefits which can be gained from the industrial implementations of the equipment were considered. Further topics which may be investigated as an extension of this work are given.

Is it all tough talking at the top? A post-structuralist analysis of the construction of gendered speaker identities of British business leaders within interview narratives

This paper uses a feminist post-structuralist approach to examine the gendered identities of a sample of British business leaders in Britain. While recent national surveys offer many material reasons why women are acutely under-represented as business leaders, the role of language is rarely addressed. This paper explores the ways in which ten senior women and men construct their sense of leadership identities through the medium of interview narratives. Drawing upon two poststructuralist models of analysis (Derrida’s 1987 theory of deconstruction and Bakhtin’s 1927/1981 concept of double-voiced discourse), the paper shows how both females and males are able to shift pragmatically between interwoven corporate discourses, which demand competing cultural allegiances from one moment to the next, allegiances constantly tested by the rapid change and uncertainty that characterise global business. While male leaders experience a relative freedom of movement between different cultural discourses, female leaders are circumscribed by negative and reductive representations of female speech and behaviour. In sum, senior women are required constantly to observe, review, police and repair their use of leadership language, which potentially undermines their confidence and authority as leaders.