Microstructural analysis of surface and interface zones in concrete

Several of OPC paste and concrete specimens, with different mix proportions, were cast against CPF and impermeable formwork (IF) and the profiles of pore structure, microhardness and scratch hardness of the cover zone were established. The chloride ingress and the depth of carbonation of the surface zone of concrete cast against CPF and IF were investigated. The main mechanisms controlling the ECR processes and the factors affecting such treatment were critically reviewed. Subsequently, as a means of restoring passivation of steel embedded in carbonated concrete, such HCP specimens were subjected to ECR. The influence of ECR on the chemistry of the pore solution and the microstructure of the surface and the steel/cement past interface zones were also studied. The main findings of this investigation were as follows: (a) The thickness of the microstructure gradient of cover concrete is significantly decreased with increasing period of water curing but is relatively unaffected by curing temperature, w/e ratio and the use of cement replacement materials. (b) The scratch hardness technique was shown to be potentially useful for characterising the microstructure and microhardness gradients of the surface zone. (c) A relationship between the microstructure gradient and mass transport properties of the surface zone was established. (d) The use of CPF resulted in a significant reduction in porosity of both the cement paste matrix and the aggregate/cement paste transition zone, and a marked improvement in the resistance of the surface zone to carbonation and the ingress of chloride ions. (e) The ECR treatment resulted in a marked densification of the pore structure and in changes to the pore solution chemistry and the cement phases of near-surface and steel/cement paste transition zones. This effect was more pronounced with current density, period of treatment and particularly with the use of sodium phosphate as an electrolyte.

Chloride resistance and durability of cement paste and concrete containing metakaolin

Metakaolin (MK), a calcined clay, was included as a partial cement replacement material, at up to 20% by weight of binder, in cement pastes and concrete, and its influence on the resistance to chloride ingress investigated. Reductions in effective chloride diffusion coefficients through hardened cement paste were obtained for binary blends and by combining OPC, MK and a second cement replacement material of pulverised fuel ash or ground granulated blast furnace slag. Steady state oxygen diffusion measurements through hardened cement pastes measured using an electrochemical cell showed that the interaction between charged species and the pore surfaces is a major factor in determining chloride diffusion rate. Rheology of the binder, particularly at high MK replacement levels, was found to have a dramatic influence on the diffusion performance of cement pastes. It was concluded that plasticising admixtures are essential for adequate dispersion of MK in cement pastes. Chloride concentration profile analysis of the concrete cylinders, exposed to sodium chloride solution for one year, was employed to obtain apparent chloride diffusion coefficients for concrete specimens. MK was found to reduce the depth of chloride penetration into concrete when compared with that of unblended mixes. Corrosion rate and corrosion potential measurements were taken on steel bars embedded in concrete exposed to a saline environment under conditions of cyclic wetting and drying. The initiation time for corrosion was found to be significantly longer for MK blended mixes than for plain OPC systems. The aggregate-paste interfacial zone of MK blended systems was investigated by steady state diffusion of chloride ions through mortar containing glass beads as model aggregate. For the model aggregate specimens tested the work confirmed the hypothesis that properties of the bulk paste are the controlling factors in ionic diffusion through mortar.

Acoustic emission and yield in sand

An experimental investigation into the Acoustic Emission (AE) response of sand has been undertaken, and the use of AE as a method of yield point identification has been assessed. Dense, saturated samples of sand were tested in conventional triaxial apparatus. The measurements of stresses and strains were carried out according to current research practice. The AE monitoring system was integrated with the soil mechanics equipment in such a way that sample disturbance was minimised. During monotonically loaded, constant cell pressure tests the total number of events recorded was found to increase at an increasing rate in a manner which may be approximated by a power law. The AE response of the sand was found to be both stress level and stress path dependent. Undrained constant cell pressure tests showed that, unlike drained tests, the AE event rate increased at an increasing rate; this was shown to correlate with the mean effective stress variation. The stress path dependence was most noticeable in extension tests, where the number of events recorded was an order of magnitude less than that recorded in comparable compression tests. This stress path dependence was shown to be due to the differences in the work done by the external stresses. In constant cell pressure tests containing unload/reload cycles it was found that yield could be identified from a discontinuity in the event rate/time curve which occurred during reloading. Further tests involving complex stress paths showed that AE was a useful method of yield point identification. Some tests involving large stress reversals were carried out, and AE identified the inverse yield points more distinctly than conventional methods of yield point identification.

Increasing competitiveness of third party logistics with RFID

Competition in the 3PL market continues to intensify as providers compete to win and retain clients. 3PL providers are required to reduce costs while offering tailored innovative logistical solutions in order to remain competitive. 3PL providers can reduce costs through the consolidation of assets and introduction of cross-docking activities. Innovative logistical services can be tailored to each client via the introduction of real-time data updates. This paper highlights that RFID enabled RTE can assist in improvements of both these areas through increased network visibility. A framework is presented where the 3PL provider focuses on asset reduction, asset utilisation, real-time data employment and RTE cycle time reduction in order to enhance competitiveness. © 2011 IEEE.

The development of chemical exposure limits for the workplace

The thesis examines and explains the development of occupational exposure limits (OELs) as a means of preventing work related disease and ill health. The research focuses on the USA and UK and sets the work within a certain historical and social context. A subsidiary aim of the thesis is to identify any short comings in OELs and the methods by which they are set and suggest alternatives. The research framework uses Thomas Kuhn's idea of science progressing by means of paradigms which he describes at one point, `lq ... universally recognised scientific achievements that for a time provide model problems and solutions to a community of practitioners. KUHN (1970). Once learned individuals in the community, `lq ... are committed to the same rules and standards for scientific practice. Ibid. Kuhn's ideas are adapted by combining them with a view of industrial hygiene as an applied science-based profession having many of the qualities of non-scientific professions. The great advantage of this approach to OELs is that it keeps the analysis grounded in the behaviour and priorities of the groups which have forged, propounded, used, benefited from, and defended, them. The development and use of OELs on a larger scale is shown to be connected to the growth of a new profession in the USA; industrial hygiene, with the assistance of another new profession; industrial toxicology. The origins of these professions, particularly industrial hygiene, are traced. By examining the growth of the professions and the writings of key individuals it is possible to show how technical, economic and social factors became embedded in the OEL paradigm which industrial hygienists and toxicologists forged. The origin, mission and needs of these professions and their clients made such influences almost inevitable. The use of the OEL paradigm in practice is examined by an analysis of the process of the American Conference of Governmental Industrial Hygienists, Threshold Limit Value (ACGIH, TLV) Committee via the Minutes from 1962-1984. A similar approach is taken with the development of OELs in the UK. Although the form and definition of TLVs has encouraged the belief that they are health-based OELs the conclusion is that they, and most other OELs, are, and always have been, reasonably practicable limits: the degree of risk posed by a substance is weighed against the feasibility and cost of controlling exposure to that substance. The confusion over the status of TLVs and other OELs is seen to be a confusion at the heart of the OEL paradigm and the historical perspective explains why this should be. The paradigm has prevented the creation of truly health-based and, conversely, truly reasonably practicable OELs. In the final part of the thesis the analysis of the development of OELs is set in a contemporary context and a proposal for a two-stage, two-committee procedure for producing sets of OELs is put forward. This approach is set within an alternative OEL paradigm. The advantages, benefits and likely obstacles to these proposals are discussed.

Reducing dependence on big brother:Higher Education looks for innovative funding opportunities

This paper presents innovative programs that business schools can utilize to reduce dependence on public funds. A review of the literature shows the theoretical and empirical foundation of higher education funding dilemmas. While higher education is moving towards a global ambition, scarcity hinders governments to fully support programs long-term; thus, cost-sharing and cost-shifting measures must occur for higher education to support current programs. In this study, we examine two universities (one U.S. and one U.K.) and provide practical summaries of programs that have provided additional funds. We show that diversity of funding sources is essential for survival of higher education institutions. Market forces require competition to reduce higher education operational costs while providing students and corporate clients an a la carte educational experience.

An agent approach to improving radio frequency identification enabled Returnable Transport Equipment

Returnable transport equipment (RTE) such as pallets form an integral part of the supply chain and poor management leads to costly losses. Companies often address this matter by outsourcing the management of RTE to logistics service providers (LSPs). LSPs are faced with the task to provide logistical expertise to reduce RTE related waste, whilst differentiating their own services to remain competitive. In the current challenging economic climate, the role of the LSP to deliver innovative ways to achieve competitive advantage has never been so important. It is reported that radio frequency identification (RFID) application to RTE enables LSPs such as DHL to gain competitive advantage and offer clients improvements such as loss reduction, process efficiency improvement and effective security. However, the increased visibility and functionality of RFID enabled RTE requires further investigation in regards to decision‐making. The distributed nature of the RTE network favours a decentralised decision‐making format. Agents are an effective way to represent objects from the bottom‐up, capturing the behaviour and enabling localised decision‐making. Therefore, an agent based system is proposed to represent the RTE network and utilise the visibility and data gathered from RFID tags. Two types of agents are developed in order to represent the trucks and RTE, which have bespoke rules and algorithms in order to facilitate negotiations. The aim is to create schedules, which integrate RTE pick‐ups as the trucks go back to the depot. The findings assert that: - agent based modelling provides an autonomous tool, which is effective in modelling RFID enabled RTE in a decentralised utilising the real‐time data facility. ‐ the RFID enabled RTE model developed enables autonomous agent interaction, which leads to a feasible schedule integrating both forward and reverse flows for each RTE batch. ‐ the RTE agent scheduling algorithm developed promotes the utilisation of RTE by including an automatic return flow for each batch of RTE, whilst considering the fleet costs andutilisation rates. ‐ the research conducted contributes an agent based platform, which LSPs can use in order to assess the most appropriate strategies to implement for RTE network improvement for each of their clients.

English commonhold:a failed experiment?

Commonhold is a new modified form of freehold tenure and represents the meritworthy objective of better spreading around the freehold ownership of land and the bringing to an end the notion of leasehold tenure in relation to phsyically interdependent buildings. This article considers the nature of English Commonhold as a new modified species of freehold tenure for physically interdependent buildings and seeks to investigate the reason(s) as to its non-use in England and Wales. The paper surveys current literature so as to highlight various contemporary academic and professional criticisms of the current Commonhold Scheme as laid out in the Commonhold and Leasehold Reform Act 2002 and it also includes the results of an emprical survey commissioned by the author which details the perception of Commonhold from the perspective of conveyancing solciitors and their clients. Certain conclusions are drawn which attempt to explain the lack of enthusiasm for Commonhold amongst the property industry and a number of reccommendations are made as to how the use of Commonhold in England and Wales can be increased.

From 3LSP (Third Party Logistics Service Provider) to 4LSP (Fourth Party Logistics Service Provider):a case study from Ireland

Increased competition, geographically expanded marketplaces, technology replication and an ever discerning consumer base, are reasons why companies need to regularly reappraise their competencies in terms of activities and functions they perform themselves. Where viable alternatives exist, companies should consider outsourcing of non-core activities and functions. Within SCM (Supply Chain Management) it could be preferable if a “one stop shop” existed for companies seeking to outsource functions identified as non-core. “Traditionally” structured LSP’s who have concentrated their service offer around providing warehousing and transport activities are potentially at a crossroads – clients and potential clients requiring “new” services which could increase LSP’s revenues if provided, whilst failure to provide could perhaps result in clients seeking outsourced services elsewhere.

Translating specialised texts:an overview of key factors involved in translator training for specialized translation

Translators wishing to work on translating specialised texts are traditionally recommended to spend much time and effort acquiring specialist knowledge of the domain involved, and for some areas of specialised activity, this is clearly essential. For other types of translation-based, domain-specific of communication, however, it is possible to develop a systematic approach to the task which will allow for the production of target texts which are adequate for purpose, in a range of specialised domains, without necessarily having formal qualifications in those areas. For Esselink (2000) translation agencies, and individual clients, would tend to prefer a subject expert who also happens to have competence in one or more languages over a trained translator with a high degree of translation competence, including the ability to deal with specialised translation tasks. The problem, for the would-be translator, is persuading prospective clients that he or she is capable of this. This paper will offer an overview of the principles used to design training intended to teach trainee translators how to use a systematic approach to specialised translation, in order to extend the range of areas in which they can tackle translation, without compromising quality or reliability. This approach will be described within the context of the functionalist approach developed in particular by Reiss and Vermeer (1984), Nord (1991, 1997) inter alia.

Marital counselling: follow-up study of marriage guidance clients: perceptions of the agency, the process and outcomes. Available in 2 volumes.

This study is a consumer-survey conducted with former Marriage Guidance Council clients. The objectives were to identify and examine why they chose the agency, what their expectations and experiences were of marital counselling and whether anything was achieved. The material was derived from tape recorded interviews with 51 former M.G. clients (17 men and 34 women) from 42 marriages and with 21 counsellors; data from written material and a card-sort completed by the research sample; and the case record sheets of the research population (174 cases). The results from the written data of clients showed that 49% were satisfied with counselling, 25.5% were satisfied in some ways but not in others, and 25.5% were dissatisfied. Forty-six percent rated they had benefited from counselling, either a great deal or to some degree, 4% were neutral and 50% recorded they had not benefited. However the counsellors' assessments were more optimistic. It was also ascertained that 50% of the research sample eventually separated or divorced subsequent to counselling. A cross-check revealed that the majority who rated they were satisfied with counselling were those who remained married, whilst dissatisfied clients were the ones who unwillingly separated or divorced. The study then describes, discusses and assesses the experiences of clients in the light of these findings on a number of dimensions. From this it was possible to construct a summary profile of a "successful" client describing the features which would contribute to "success". Two key themes emerged from the data. (1) the discrepancy between clients expectations and the counselling offered, which included mis­ match over the aims and methods of counselling, and problem definition; and (2) the importance of the client/counsellor relationship. The various implications for the agency are then discussed which include recommendations on policy, the training of counsellors and further research.