Human Rights in Northern Ireland 2009-10

This report surveys the legislative and judicial developments in human rights law within Northern Ireland in the years 2009 and 2010, highlighting the respects in which the law was or was not in compliance with international human rights standards, in particular those laid down in the European Convention on Human Rights.

Criminal Justice Reforms in Northern Ireland: The Agents of Change

This chapter examines who and what brought about the transformation in the criminal justice system of Northern Ireland between 1998 and 2015, seeking to pinpoint the critical moments which stimulated the reforms, how they were delivered, and through what processes they are now being maintained. It seeks to identify the key agents of change and considers whether it is possible to generalise from Northern Ireland���s experience so that other conflicted societies might benefit from the lessons learned.

The Role of Water Content and Paste Proportion on Physico-mechanical Properties of Alkali Activated Fly Ash���Ggbs Concrete

The growth of the construction industry worldwide poses a serious concern on the sustainability of the building material production chain, mainly due to the carbon emissions related to the production of Portland cement. On the other hand, valuable materials from waste streams, particularly from the metallurgical industry, are not used at their full potential. Alkali activated concrete (AAC) has emerged in the last years as a promising alternative to traditional Portland cement based concrete for some applications. However, despite showing remarkable strength and durability potential, its utilisation is not widespread, mainly due to the lack of broadly accepted standards for the selection of suitable mix recipes fulfilling design requirements, in particular workability, setting time and strength. In this paper, a contribution towards the design development of AAC synthetized from pulverised fuel ash (60%) and ground granulated blast furnace slag (40%) activated with a solution of sodium hydroxide and sodium silicate is proposed. Results from a first batch of mixes indicated that water content influences the setting time and that paste content is a key parameter for controlling strength development and workability. The investigation indicated that, for the given raw materials and activator compositions, a minimum water to solid (w/s) ratio of 0.37 was needed for an initial setting time of about 1 hour. Further work with paste content in the range of 30% to 33% determined the relationship between workability and strength development and w/s ratio and paste content. Strengths in the range of 50 - 60 MPa were achieved.

Sustainable binders for concrete: a structured approach from waste screening to binder composition development

Worldwide, the building sector requires the production of 4 billion tonnes of cement annually, consuming more than 40% of global energy. Alkali activated ���cementless��� binders have recently emerged as a novel eco-friendly construction material with a promising potential to replace ordinary Portland cement. These binders consist of a class of inorganic polymer formed mainly by the reaction between an alkaline solution and an aluminosilicate source. Precursor materials for this reaction can be found in secondary material streams from different industrial sectors, from energy to agro-alimentary. However, the suitability of these materials in developing the polymerisation reaction must be assessed through a detailed chemical and physical characterisation, ensuring the availability of required chemical species in the appropriate quantity and physical state. Furthermore, the binder composition needs to be defined in terms of proper alkali activation dosages, water content in the mix, and curing conditions. The mix design must satisfy mechanical requirements and compliance to desired engineering properties (workability, setting time) for ensuring the suitability of the binder in replacing Portland cement in concrete applications. This paper offers a structured approach for the development of secondary material-based binders, from their identification to mix design and production procedure development. Essential features of precursor material can be determined through chemical and physical characterisation methods and advanced microscope techniques. Important mixing parameters and binder properties requirements are examined and some examples of developed binders are reported.

Alkali activated fuel ash and slag mixes:optimization study from paste to concrete building blocks

Alkali activated binders, based on ash and slag, also known as geopolymers, can play a key role in reducing the carbon footprint of the construction sector by replacing ordinary Portland cement in some concretes. Since 1970s, research effort has been ongoing in many research institutions. In this study, pulverized fuel ash (pfa) from a UK power plant, ground granulated blast furnace slag (ggbs) and combinations of the two have been investigated as geopolymer binders for concrete applications. Activators used were sodium hydroxide and sodium silicate solutions. Mortars with sand/binder ratio of 2.75 with several pfa and ggbs combinations have been mixed and tested. The optimization of alkali dosage (defined as the Na2O/binder mass ratio) and modulus (defined as the Na2O/SiO2 mass ratio) resulted in strengths in excess of 70 MPa for tested mortars. Setting time and workability have been considered for the identification of the best combination of pfa/ggbs and alkali activator dosage for different precast concrete products. Geopolymer concrete building blocks have been replicated in laboratory and a real scale factory trial has been successfully carried out. Ongoing microstructural characterization is aiming to identify reaction products arising from pfa/ggbs combinations.

Repeal the HRA and Rely on the Common Law?

This piece contemplates whether the common law could fill the gaps in human rights protection if the UK's Human Rights Act 1998 were to be repealed. It looks at how the common law protected human rights before the Act came into force, what difference the Act has made, how the common law has become side-lined as a result, how in recent cases it has begun to play a more central role, and what more more needs to be done to develop it in ways which ensure that if the Human Rights Act were to be repealed it would not be particularly missed.

Chloride transport and the resulting corrosion of steel bars in alkali activated slag concretes

As the relative performance of alkali activated slag (AAS) concretes in comparison to Portland cement (PC) counterparts for chloride transport and resulting corrosion of steel bars is not clear, an investigation was carried out and the results are reported in this paper. The effect of alkali concentration and modulus of sodium silicate solution used in AAS was studied. Chloride transport and corrosion properties were assessed with the help of electrical resistivity, non-steady state chloride diffusivity, onset of corrosion, rate of corrosion and pore solution chemistry. It was found that: (i) although chloride content at surface was higher for the AAS concretes, they had lower chloride diffusivity than PC concrete; (ii) pore structure, ionic exchange and interaction effect of hydrates strongly influenced the chloride transport in the AAS concretes; (iii) steel corrosion resistance of the AAS concretes was comparable to that of PC concrete under intermittent chloride ponding regime, with the exception of 6% Na2O and Ms of 1.5; (iv) the corrosion behaviour of the AAS concretes was significantly influenced by ionic exchange, carbonation and sulphide concentration; (v) the increase of alkali concentration of the activator generally increased the resistance of AAS concretes to chloride transport and reduced its resulting corrosion, and a value of 1.5 was found to be an optimum modulus for the activator for improving the chloride transport and the corrosion resistance.

Human Rights in Northern Ireland in 2013

This is a report of the variety of developments in human rights law in Northern Ireland during the calendar year 2013. It pays particular attention to references to human rights issues in judicial decisions taken within Northern Ireland.

Chloride induced corrosion of steel bars in alkali activated slag concretes

The studies on chloride induced corrosion of steel bars in alkali activated slag (AAS) concretes are scarcely reported in the past. In order to make this issue clearer and compare the corrosion performance of AAS with Portland cement (PC) counterpart, an investigation was carried out and the results are reported in this paper. Corrosion properties were assessed with the help of rate of corrosion, electrical resistivity and pore solution chemistry. It was found that: (i) steel corrosion resistance of the AAS concretes was comparable or in some cases even worse than that of Portland cement (PC) concrete under intermittent chloride ponding regime; (ii) the corrosion behaviour of the AAS concretes was significantly influenced by ionic exchange, carbonation and sulphide concentration; (iii) the increase of alkali concentration of the activator generally reduced chloride resulting corrosion, and a value of 1.5 was found to be an optimum modulus for the activator for improving the corrosion resistance.

Retrieving Similar Discussion Forum Threads: A Structure based Approach

Online forums are becoming a popular way of finding useful<br/>information on the web. Search over forums for existing discussion<br/>threads so far is limited to keyword-based search due<br/>to the minimal effort required on part of the users. However,<br/>it is often not possible to capture all the relevant context in a<br/>complex query using a small number of keywords. Examplebased<br/>search that retrieves similar discussion threads given<br/>one exemplary thread is an alternate approach that can help<br/>the user provide richer context and vastly improve forum<br/>search results. In this paper, we address the problem of<br/>finding similar threads to a given thread. Towards this, we<br/>propose a novel methodology to estimate similarity between<br/>discussion threads. Our method exploits the thread structure<br/>to decompose threads in to set of weighted overlapping<br/>components. It then estimates pairwise thread similarities<br/>by quantifying how well the information in the threads are<br/>mutually contained within each other using lexical similarities<br/>between their underlying components. We compare our<br/>proposed methods on real datasets against state-of-the-art<br/>thread retrieval mechanisms wherein we illustrate that our<br/>techniques outperform others by large margins on popular<br/>retrieval evaluation measures such as NDCG, MAP, Precision@k<br/>and MRR. In particular, consistent improvements of<br/>up to 10% are observed on all evaluation measures

Influence of service loading and the resulting micro-cracks on chloride resistance of concrete

Chloride-induced corrosion of steel in reinforced concrete structures is one of the main problems affecting their durability, but most previous research projects and case studies have focused on concretes without cracks or not subjected to any structural load. Although it has been recognised that structural cracks do influence the chloride transport and chloride induced corrosion in reinforced concrete structures, there is little published work on the influence of micro-cracks due to service loads on these properties. Therefore the effect of micro-cracks caused by loading on chloride transport into concrete was studied. Four different stress levels (0%, 25%, 50% and 75% of the stress at ultimate load ��� fu) were applied to 100 mm diameter concrete discs and chloride migration was measured using a bespoke test setup based on the NT BUILD 492 test. The effects of replacing Portland cement CEMI by ground granulated blast-furnace slag (GGBS), pulverised fuel ash (PFA) and silica fume (SF) on chloride transport in concrete under sustained loading were studied. The results have indicated that chloride migration coefficients changed little when the stress level was below 50% of the fu; however, it is desirable to keep concrete stress less than 25% fu if this is practical. The effect of removing the load on the change of chloride migration coefficient was also studied. A recovery of around 50% of the increased chloride migration coefficient was found in the case of concretes subjected to 75% of the fu when the load was removed.

Internal curing in cement-based materials

O desenvolvimento de bet��es de elevado desempenho, durante o in��cio da d��cada de 80, revelou que este tipo particular de materiais com base em cimento �� suscept��vel a problemas de cura. S��o bem conhecidos os efeitos dos fen��menos autog��neos em sistemas de elevado desempenho com base em cimento, nomeadamente a fissura����o em idade jovem. Esta ��, ali��s vista como a maior limita����o no desenvolvimento de novos materiais com durabilidade superior. Desenvolvimentos recentes de m��todos de cura interna provaram ser uma boa estrat��gia de mitiga����o dos efeitos da auto-disseca����o destes sistemas, onde a presente tese ganha o seu espa��o no tempo. Este estudo centra-se essencialmente em sistemas de elevado desempenho com base em cimento com cura interna atrav��s de part��culas superabsorventes, dando particular import��ncia �� altera����o de volume em idade jovem. Da an��lise mais aprofundada deste m��todo, resultam algumas limita����es na sua aplicabilidade, especialmente em sistemas modificados com s��lica de fumo. Conclui-se que a natureza f��sica e qu��mica dos pol��meros superabsorventes pode afectar significativamente a efici��ncia da cura interna. Em adi����o, os mecanismos de cura interna s��o discutidos mais profundamente, sendo que para al��m dos mecanismos baseados em fen��menos f��sicos e qu��micos, parecem existir efeitos mec��nicos significativos. V��rias t��cnicas foram utilizadas durante o decorrer desta investiga����o, com o objectivo, para al��m da caracteriza����o de certas propriedades dos materiais, de perseguir as quest��es deixadas em aberto pela comunidade internacional, relativamente aos mecanismos que fundamentam a explica����o dos fen��menos autog��neos. Como exemplo, s��o apresentados os estudos sobre hidrata����o dos sistemas para avalia����o do problema numa escala microsc��pica, em vez de macrosc��pica. Uma nova t��cnica de cura interna emerge da investiga����o, baseada na utiliza����o de agregados finos como veiculo para mitigar parcialmente a retrac����o autog��nea. At�� aqui, esta t��cnica n��o encontra par em investiga����o anterior, mas a extens��o da cura interna ou a efic��cia na mitiga����o baseada neste conceito encontra algumas limita����es. A signific��ncia desta t��cnica em prevenir a micro fissura����o �� um aspecto que est�� ainda em aberto, mas pode concluir-se que os agregados finos podem ser ben��ficos na redu����o dos efeitos da restri����o localizada no sistema, reduzindo o risco de micro fissura����o. A utiliza����o combinada de part��culas finas de agregado e pol��meros super absorventes pode ter como consequ��ncia bet��o sem microfissura����o, ou pelo menos com nanofissura����o.

Biomass fly ash incorporation in cement based materials

In recent years, pressures on global environment and energy security have led to an increasing demand on renewable energy sources, and diversification of Europe���s energy supply. Among these resources the biomass could exert an important role, since it is considered a renewable and CO2 neutral energy resource once the consumption rate is lower than the growth rate, and can potentially provide energy for heat, power and transports from the same installation. Currently, most of the biomass ash produced in industrial plants is either disposed of in landfill or recycled on agricultural fields or forest, and most times this goes on without any form of control. However, considering that the disposal cost of biomass ashes are raising, and that biomass ash volumes are increasing worldwide, a sustainable ash management has to be established. The main objective of the present study is the effect of biomass fly ashes in cement mortars and concretes in order to be used as a supplementary cementitious material. The wastes analyzed in the study were collected from the fluidized bed boilers and grate boilers available in the thermal power plants and paper pulp plants situated in Portugal. The physical as well as chemical characterisations of the biomass fly ashes were investigated. The cement was replaced by the biomass fly ashes in 10, 20 and 30% (weight %) in order to investigate the fresh properties as well as the hardened properties of biomass fly ash incorporated cement mortar and concrete formulations. Expansion reactions such as alkali silica reaction (ASR), sulphate attack (external and internal) were conducted in order to check the durability of the biomass fly ash incorporated cement mortars and concretes. Alternative applications such as incorporation in lime mortars and alkali activation of the biomass fly ashes were also attempted. The biomass fly ash particles were irregular in shape and fine in nature. The chemical characterization revealed that the biomass fly ashes were similar to a class C fly ash. The mortar results showed a good scope for biomass fly ashes as supplementary cementitious materials in lower dosages (<20%). The poor workability, concerns about the organic content, alkalis, chlorides and sulphates stand as the reasons for preventing the use of biomass fly ash in high content in the cement mortars. The results obtained from the durability tests have shown a clear reduction in expansion for the biomass fly ash mortars/concretes and the binder blend made with biomass fly ash (20%) and metakaolin (10%) inhibited the ASR reaction effectively. The biomass fly ash incorporation in lime mortars did not improve the mortar properties significantly though the carbonation was enhanced in the 15-20% incorporation. The biomass fly ash metakaolin blend worked well in the alkali activated complex binder application also. Portland cement free binders (with 30-40 MPa compressive strength) were obtained on the alkali activation of biomass fly ashes (60-80%) blended with metakaolin (20-40%).

Cimentos de fosfato de magn��sio: consolida����o e caracteriza����o

A rea����o entre o ��xido de magn��sio (MgO) e o fosfato de monoam��nio (MAP), �� temperatura ambiente, origina os cimentos de fosfato de magn��sio, materiais caracterizados pela sua presa r��pida e pelas excelentes propriedades mec��nicas adquiridas precocemente. As propriedades finais s��o dependentes, essencialmente, da composi����o do cimento (raz��o molar magn��sia:fosfato e utiliza����o de retardantes de presa) mas tamb��m s��o influenciadas pela reatividade da magn��sia utilizada. Neste trabalho, a rea����o foi caracterizada atrav��s do estudo da influ��ncia da raz��o molar MgO:MAP (variando de 1:1 at�� 8:1), da presen��a e teor de aditivos retardantes (��cido b��rico, ��cido c��trico e tripolifosfato de s��dio) e da varia����o da ��rea superficial espec��fica da magn��sia (conseguida por calcina����o do ��xido), no tempo de presa, na temperatura m��xima atingida e nas fases cristalinas finais formadas. A rea����o de presa pode ser comparada �� hidrata����o do cimento Portland, com a exist��ncia de 4 est��gios (rea����o inicial, indu����o, acelera����o e desacelera����o), com a diferen��a que estes est��gios ocorrem a velocidade muito mais alta nos cimentos de fosfato de magn��sio. Este estudo foi realizado utilizando a espetroscopia de imped��ncias, acompanhada pela monitoriza����o da evolu����o de temperatura ao longo do tempo de rea����o e, por paragem de rea����o, identificando as fases cristalinas formadas. A investiga����o do mecanismo de rea����o foi complementada com a observa����o da microestrutura dos cimentos formados e permitiu concluir que a origem da magn��sia usada n��o afeta a rea����o nem as propriedades do cimento final. A metodologia de superf��cie de resposta foi utilizada para o estudo e otimiza����o das caracter��sticas finais do produto, tendo-se mostrado um m��todo muito eficaz. Para o estudo da varia����o da ��rea superficial espec��fica da magn��sia com as condi����es de calcina����o (temperatura e tempo de patamar) usou-se o planeamento fatorial de experi��ncias tendo sido obtido um modelo matem��tico que relaciona a resposta da ��rea superficial espec��fica da magn��sia com as condi����es de calcina����o. As propriedades finais dos cimentos (resist��ncia mec��nica �� compress��o e absor����o de ��gua) foram estudadas utilizando o planeamento simplex de experi��ncias, que permitiu encontrar modelos que relacionam a propriedade em estudo com os valores das vari��veis (raz��o molar MgO:MAP, ��rea superficial espec��fica da magn��sia e quantidade de ��cido b��rico). Estes modelos podem ser usados para formular composi����es e produzir cimentos com propriedades finais espec��ficas.