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The use of steel fibres to reinforce plain concrete has shown remarkable improvement in the tensile and flexural properties with respect to ductility and strength in tension through crack control, with optimum performance reported at 0.75% steel fibre content in bending and effect on the serviceability limit state design. Additional benefits in the mechanical properties have been reported when used in self-compacting concrete because of the alignment it provides to the steel fibre to control crack amongst other (environmental, health, and safety) benefits it offers. The use of different types of steel fibres have contributed to the improved performance of concrete over the decades, yet the hooked-end steel fibre still provides the most significant enhancement in the material properties when compared to others, which accounts for the 67% of the steel fibres sold. Moreover, up till date, there persists variability in the scatter of the tensile and flexural properties of steel fibre reinforced concrete, which accounts for higher material safety factors in current design practice, making it difficult to define an acceptable design standard for the material behaviour in tension. This study aims to use the new innovative S1, M1, and M2 hooked-end steel fibres to reduce the large scatter of the material properties in a bid to lower design safety allowance for future SFRC applications. The study adopts the experimental research design due to limited empirical data, and it comprises the use of eight experimental test methods which include the uniaxial direct tension test, bending test methods, pull-out test, amongst others. The research variables include the effect of the S1, M1, and M2 macro hooked-end steel fibre types; effect of 0%, 0.25%, 0.5%, 0.75%, and 1% steel fibre content; and steel fibre hybridisation (macro: micro steel fibres) on the material properties of self-compacting concrete. The effect of S1, M1, and M2 steel fibre types at 10mm, 20mm, and 30mm embedded depths on the pull-out parameters is also studied as well as the influence of the M2 steel fibre type on the flexural properties and resistance in a large-scale beam test. The results show that the shape and geometrical characteristics of the hooked-end steel fibres influence the workability of the concrete mix with a maximum reduction of up to 9%, and they have a significant effect on the material properties in the pull-out test, direct tension test, bending test, and additional benefits seen in steel fibre hybridisation with compressive strength increasing from 64MPa to 88MPa. The use of the M1 and M2 hooked-end steel fibres with double hooks modifies the softening behaviour during stress degradation in a pull-out test because of the influence on the residual stresses. Maximum values of up to 120% in the pull-out load and 150% in the pull-out dissipated energy are recorded for M1 and M2 respectively when compared to S1 as the embedded depth increases from 10mm to 30mm. The ultimate bond strengths derived are 9.86MPa for S1, 20.53MPa for M1, and 26.74MPa for M2. In the tension test, maximum increments of 4% for S1, 9% for M1, and 17% for M2 are observed in the mean tensile strength to the mean ultimate tensile strength only at high steel fibre content (1%), which depicts hardening behaviour. However, in the bending test, the maximum mean ultimate flexural strengths recorded are 15% for S1, 11% for M1, and 15% for M2 when compared to the mean flexural strength. Optimum performance in bending varies-S1 at 0.75% fibre content, M1 at 0.25%, and M2 at 1%. However, in tension, optimum is at 1% fibre content for S1, M1, and M2. Steel hybridisation shows a significant increase of up to 40% in both tensile and flexural strengths in M2 condition. Meanwhile, in S1 condition, 77% is seen in tensile strength while 13% is observed in the flexural strength. Optimum performance in the flexural strength in both conditions is observed at 75% Macro + 25% Micro. However, in tension, optimum tensile strength is seen at 25% Macro + 75% Macro. The constant parameters (K) and (C) which define the relationship between the tensile and bending stress as well as the tensile and bending strain at initial crack propagation for different fibre contents and hybridisation ratios are derived. The low residual stress values observed in the tensile and bending tests allow for a bi-linear relationship to describe the material behaviour in tension, which the proposed tensile material model from this study is based on. The proposed model has been calibrated from existing material models, and it uses key design parameters alpha (α) and eigen (ξ) ratios to define critical characteristic points which describe the material's ductile nature and energy absorption. The study shows that, at the structural level, steel fibre inclusion in self-compacting concrete produces higher first crack load and ultimate load of 13% when compared to a similar beam without steel fibres and a reduction of up to 40% in the corresponding deflection. There is a 55% reduction in the crack spacing. The failure strain is also reduced by 56%, which results in lower energy absorption, reduced toughness, and ductility, because of the change in the failure behaviour, making the beam more catastrophic if used in earthquake resistant structures. The study concludes that there is the potential to reduce the material safety factor of SFRC structures and the associated design cost because of the reduction in the large scatter of the tensile and flexural material properties offered by the M1 and M2 hooked-end steel fibres, when compared to S1, although variability still exists in the scatter. A maximum of up to 42% reduction in the scatter is observed in the material properties associated with the pull- out test, 26% with the tensile test, 21% with the bending test, 75% with steel hybridisation, and 97% at the structural level.

Despite the unprecedented permeation of Building Information Modelling (BIM) and availability of a wide range of collaboration platforms, architects and structural engineers, for the most part, act as separate teams. Therefore, linking architectural models with those of structural engineers remains a labour-dependent and a cumbersome activity. This research proposed potential solutions to improve the structural design processes at the early stages by integrating architectural and structural models and generating alternative structural models for the same architectural model automatically. The research proposed a framework and a proof-of-concept prototype, which used the architectural model and relevant parametric data as input to design and analyse different parametric structural models through an automatic process. This process helps to reduce the iterative structural design process and improve the collaboration between the structural engineers and architects through automation within the BIM platform. The research leveraged the importance of using automation in the structural design process and the collaboration between structural engineers and other disciplines, particularly with the architects. The research started with an exploratory approach, using a comprehensive literature review to highlight the existing challenges in the structural design, analysis and optimisation processes, particularly at the early stages. Thereafter, based on the information received from the literature review a Conceptual Structural Design and Optimisation (CSDO) framework was developed to solve the identified challenges. In order to justify the research and validate the conceptual framework, an online questionnaire was distributed between professionally accredited structural engineers of the Institution of Structural Engineers (IStructE), The Institution of Civil Engineers (ICE) and the American Society of Civil Engineers(ASCE). The questionnaire uncovered valuable information about the existing challenges, and potential solutions that justifies the research knowledge gap, and the information obtained helped to improve the framework. Thereafter, an extended framework was developed and aimed at improving the integration and interoperability between architectural and structural model in an automatic process in BIM. Hence, a proof of concept prototype was developed to demonstrate the workability of the extended framework. Various case studies demonstrated the workability of the prototype in different areas and type of structures. Finally, the proof of concept prototype was validated in several semi-structured interviews with the academic staff of the University of Portsmouth and chartered structural engineers in industry with civil and structural engineering backgrounds. Furthermore, a focus group was conducted with six domain experts from the Autodesk research and a development team to validate the prototype and receive feedback for further development and future work. This research contributes to the field by presenting a novel solution, capable of automated generation of structural design, based on architectural models and design requirements (input data). This research provides a practical demonstration of a fully integrated architectural/structural design system. Moreover, this research contributes to the field by extending the outcomes of existing literature that proposed optimisation of structural design, albeit in one dimension, like shape, topology and size in structural design. The proposed framework and proof of concept prototype considers all the dimensions of the optimisation simultaneously and provides a valuable source of reference for future research in this area.

This thesis provides a political economy account of how four small open economies – Finland, Denmark, the Netherlands, and Ireland – have coped with the adaptation required by the exogenous pressures of Europeanisation over a period of 25 years. The research is grounded in Polyanian conceptualising of the interaction of States and markets using Varieties of Capitalism as a theoretical foundation. Starting with Katzenstein’s (1985) comparative study as a departure point, the research evaluates how each country responded to deepening EU integration over a four stage periodisation broadly aligned to critical junctures of integration, and closing with the fifth anniversary of the Lehman Bros bank collapse on 15th September, 2013. Particular attention is paid to the Irish case, with a view to resolving the puzzling question of why its ‘Celtic Tiger’ phase of development proved to be unsustainable. The research also identifies the areas where the different Varieties of Capitalism converge and diverge. The findings are that the ‘Democratic Corporatism’ which Katzenstein identified as the means by which small open economies could cope with market forces by balancing them with social compensation, is still intact. Finland, Denmark, and the Netherlands have all made necessary reforms to welfare regimes and labour markets without compromising societal values. While having to accommodate to an extent to liberalising forces, they remain developmental states. Ireland exhibited developmentalist characteristics during the 1990s. It caught up with the rest of Europe in a material sense but not in respect of the capabilities required to carry this developmentalism forward to the new millennium. On the contrary, the 2000s saw the country make serious policy errors principally due to an intellectual failure to assimilate the requirements of living in a currency union. Moreover, democratic corporatism in an Irish context was not embedded. It is imperative that Ireland recaptures this developmentalism and repertories of action to help it do so are identified. A number of dilemmas confronting the European integration project are outlined. Foremost among them is the challenge of embarking on a course of deeper integration necessary to consolidate the future of the currency in circumstances where political legitimacy is seriously undermined by austerity. A singular focus on fiscal adjustment has resulted in a deflationary debt crisis which seems set to continue for some time. There is no obvious escape route for Ireland. Indeed the situation is much complicated by its relationship with Britain which is becoming increasingly semi-detached from Europe. Within the policy space available to it, the best course for Ireland is to reinvent itself as a Social Market Economy, as far as possible in the image of its northern European peers. For all the bleakness of the current environment there is opportunity too. The institutional architecture of EMU is so dysfunctional that it must eventually yield to reform if European integration as a project is to survive. Therein lies the possibility for a social democratic revival if a convincing narrative for it can be communicated.

The aim of this study is to investigate the mechanical behaviour of concrete reinforced by hooked end steel fibres with the effects of cement replacement materials and fibre properties on the fibre-matrix bond. The mechanical performance and specifically the pullout behaviour of steel fibres with different hook shapes and tensile strengths in various cementitious material are studied. This research also aims to investigate the behaviour of steel fibre reinforced concrete in precast jacking pipes. The cement replacements which have been used in this research included silica fume, pulverised fuel ash, limestone filler and ground granulated blast-furnace slag. In total, more than 1000 samples have been manufactured for experimental research on compressive strength, flexural behaviour of steel fibre reinforced concrete and pullout behaviour of hooked end steel fibres from cement based matrices. The effects of various parameters, such as water/binder ratio, cement replacement material type and level, hooked end shape and tensile strength of fibre on fibre-matrix pullout behaviour were determined. The results of tests and analysis indicated that improving hook shape of fibre increase the pullout strength by more than 200% and using cement replacement materials significantly influence the pullout behaviour which would be useful for the optimisation of steel fibre reinforced concrete and supporting the standardisation of pullout test. In order to investigate the performance of steel fibre reinforced concrete in an application which this material has not been used before, mechanical properties of steel fibre reinforced concrete including compressive, tensile and flexural strength properties were experimentally determined. The results were also input into finite element modelling software package DIANA in order to define the material and to model the behaviour of jacking pipes under crushing load. A laboratory-scale research was conducted on steel fibre reinforced concrete pipes. The results show a 100% improvement in maximum crushing load with inclusion of fibres compared to the plain concrete. Full-scale jacking pipes including pipes with 450-1200 mm diameter and various reinforcement systems were also tested in accordance to BS EN 1916. According to the testing and modelling analysis, in order to use steel fibre as sole reinforcement and to achieve the crushing test criteria of the relevant standard, either the mechanical properties of the material or the geometrical properties of pipes needed to be amended. Full and partial replacement of bar reinforcement by type IV steel fibres were considered as well as the potential to increase the level of cover of reinforcing bar in order to produce pipes meeting higher exposure classes. The designs obtained present the possibility of production of pipes meeting higher durability/service life requirements than is possible with the existing products. The outcome of this research may be useful to widen the potential applications of the material across civil engineering.

The Mary Rose is the only Tudor warship in existence, and as such is an important archaeological artefact. Since she was raised in 1982, and since then has undergone conservation treatment to preserve her structure while on display in the Mary Rose Museum. Displaying an artefact which has been waterlogged for 500 years, in this kind of environment, presents a number of unique challenges relating to the structure and chemistry of degraded archaeological wood. This thesis outlines several approaches to monitoring the state of the Mary Rose, and consequently the progress of her conservation treatment. This monitoring relates to both her macroscopic structural state, as well smaller scale structure, and the distribution of moisture throughout her hull. An overview of the Mary Rose and her history, of wood characteristics, degradation causes in waterlogged environments and archaeological wood behaviour, of conservation techniques, their application to comparable artefacts and of investigative techniques used with cultural heritage is first given. The methods and materials used in this thesis are then described. The Mary Rose is monitored for her MC% with core samples. The structural survey is carried out with a Total Station and a new manual method involving laser pointers for the understanding of global movements taking place on the hull. A manual survey focused on local movements is also described. Neutron imaging is used on Mary Rose wood samples to better understand the behaviour of PEG treated archaeological wood when drying. Neutron radiographies of the samples are taken during drying simulations of the conditions on the Mary Rose hull. The monitoring shows that the hull of the Mary Rose has reached MC% below 15% throughout the depth of the timbers. The structural survey shows movement taking place in the entire hull: the Decks of the ship are shifting in opposite directions, the Starboard side is folding into the Port side and the structure is moving downwards. It is also possible to relate the cracks on the ship's timbers to the fast initial loss of free water and the loss of bound water from the timbers when the ship started drying in 4 2013, but structural movements are likely connected to the lack of structural integrity. Neutron imaging underlined the peculiar drying behaviour of PEG treated wood, showing a uniform drying front rather than preferential paths following the wood structure. The method also confirmed the ability of PEG in reducing wood shrinkage upon drying. Future work is suggested, both in terms of the ship monitoring and with regards to the further analysis of drying behaviour of treated archaeological wood.

The collapse of building structures during recent earthquakes, particularly in the countries around the Kurdistan region (KR), including Turkey (2011 Van earthquake) and Iran (2003 Bam earthquake), has raised many questions about the safety of existing buildings in the region and structures that are going to be constructed in the future. The KR, which is located in northern and northeastern Iraq, is also considered to be the most hazardous region of Iraq. However, many buildings in the region, especially unreinforced masonry (URM) buildings, were not engineered to withstand seismic loads. The seismic vulnerability assessment of these types of buildings in this region is a necessary step towards the development of regional seismic retrofitting and pre-disaster mitigation plans. Fragility analysis is often used for this purpose and to graphically represent a structure’s seismic vulnerability in terms of fragility curves. Considering that there are several important uncertainties involved in such an analysis and after developing and proposing seismic zonation maps, response spectra and the seismic zone factor Z for the KR, the results of analytical fragility analyses of URM buildings in the KR indicated that the correct selection of a ground-motion intensity measure (IM) is the most important variability involved in assessing the fragility of URM buildings. The results suggest that the variability in the mechanical parameters of materials can be neglected because the variability of ground motion is considerably more substantial. Furthermore, the use of incremental dynamic analysis (IDA) and a well-selected IM allows fragility curves to be derived with only a few records (i.e., a minimum of 7 records) with the same performance as for with numerous records (i.e., 60 records). Moreover, the pronounced difference in the results when using only one IM vs. using two IMs cannot be ignored; hence, fragility surfaces are preferred over the more commonly used fragility curves. Furthermore, a framework based on using machine learning models (i.e., a wrapper-based approach) for the optimal selection of an IM for developing fragility curves is proposed in this study. The feasibility of the wrapper method for selecting the best IM is compared to a statistical regression (log-logistic regression) used to develop fragility curves and the results were encouraging. Finally, the outcomes of the study indicate that the seismic safety of the investigated low-rise buildings in the region is questionable and that these structures must be strengthened to prevent failure.

The scope of this study was the creation of a methodology that would adequately quantify and incorporate the interrelationship between the various seismic parameters and recorded structural damage. Based upon the need to establish whether traditionally selected seismic parameters were truly representative of the expected structural damage and overall structural vulnerability an extensive set of seismic data and subsequent computer assisted analyses were synthesized and used throughout this project. Having established the fact that MMI and PGA seismic parameters are currently the seismic intensity indicating parameters of choice in most contemporary vulnerability studies it was only logical to test such hypothesis based on this study‟s results. In several of the above cases discrepancies between those parameters and the overall structural damage recorded has been observed. This led to the need of identification of other potentially more suitable seismic parameters that would better and more accurately convey structural damage information. This study provided a methodology that circumvents the shortcomings of such an a-priori selection by facilitating the selection of the most descriptive, in terms of seismic damage, earthquake parameter; hence, enhancing vulnerability methodology‟s usefulness as a mitigation tool in pre-earthquake damage assessment. This has been accomplished by studying the interrelationship between various seismic intensity parameters and the overall seismic structural damaging potential recorded during the analyses undertaken in an attempt to streamline the selection of a specific seismic parameter. The thesis essentially investigated a methodology that enables such a selection that better describes a strong motion event‟s damaging potential, for any individual type of structure, in accordance with regional or selected seismic characteristics. Due to the very nature of the methodology proposed can be utilized for different types of structures other than the mid-rise reinforced concrete frame type that has been used in this project, with the necessary modifications and due care. With the identification of the aforementioned parameter, the current trend of an a-priori selection of either PGA or MMI, as structural seismic demand descriptors, can be avoided: leading to the creation of more realistic vulnerability curves. In effect, allowing for a better approximation of structural vulnerability; hence more closely approximate the observed structural damage.