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In this thesis it is demonstrated how mass transfer can be induced within a network of reticulated channels through turbulent mixing, and how this mechanism can be applied as an integrated functional structure in a building envelope. The research is based on suggestions in literature that there are transient modes of mass transfer which are active in termite mounds of the species Macrotermes michaelseni and which do not rely on steady or cross flows: is the interaction of transient air flows, induced or natural, and the geometry found in the mounds – a complex reticulated network of tunnels with variable dimensions – conducive to controlled mass transfer? My original contribution is to show that such mass transfer is possible, to demonstrate the ways which geometry and input flow interact to create turbulent mixing, and to demonstrate how these parameters may be useful to control the flow within and across building elements. The research method is structured around a series of experiments where various geometries, based on the egress complex of termite mounds, are exposed to transient fluid flows, either a controlled, low amplitude oscillation or external turbulent flow. The resulting mass transfer is measured using tracer gas measurements and visualisations using planar laser and/or fluorescent dye. It is found that the oscillations in certain conditions, which involve a combination of geometry and oscillation properties, lead to the emergence of large scale turbulent convection which can increase the mass transfer rates with up to two orders of magnitude over an unperturbed system. It is concluded that such mechanisms are potentially useful to control the flows of heat and moisture within buildings and across building envelopes. The particular properties of the described flows can complement conventional steady flows and expands the repertoire available to the building designer, enabling new types of boundaries and functional integration in the building envelope.

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Near Surface Mounted (NSM) Fibre Reinforced Polymer (FRP) reinforcement is an effective rehabilitation solution to strengthen RC structures, as it can enable higher load carrying capacity and ductility than conventional Externally Bonded Reinforcement (EBR). However, the performance of elements strengthened in flexure is still controlled by bond failure between the NSMR system and the concrete substrate. This can reduce both the effectiveness and safety of NSMR systems and should be accounted for in design. The development of high stresses due to the abrupt termination of NSMR is the main cause for the dominant end debonding failure. This type of failure is not well understood and needs to be examined in detail. The aim of this work is to achieve a comprehensive understanding of bond behaviour and debonding mechanisms of the NSMR in flexural strengthening applications both experimentally and theoretically so as to enable the development of practical and reliable design methods for RC beams strengthened in flexure with NSMR. An analytical elastic model is developed to facilitate a fundamental understanding of the distribution of bond stresses along the NSMR, especially in the region around the termination point. The model identifies differences of stress states between EBR and NSMR. However, since it is based on elastic analysis and continuum mechanics, it is unable to represent bond behaviour of NSMR at high load levels. This issue can only be examined in detail via specially developed experimental work. A total of ten RC beams, including two control beams and eight beams strengthened in flexure with CFRP and BFRP bars or strips, are tested to examine the overall structural behaviour of RC beams retrofitted with NSMR of different embedment lengths. Tested beams are heavily instrumented to examine the influence of yield penetration along the internal steel bars on the bond behaviour of the NSM reinforcement within the shear spans and the resulting debonding mechanisms. NSMR enhanced flexural capacity by up to 50% and the dominant failure mode was end debonding after yielding. The experimental results show that yielding of the steel reinforcement penetrates in the shear span much further than predicted through classic section analysis, reaching near or even beyond the termination point. The experimental evidence is used to develop a new simple, yet effective methodology to estimate the minimum embedment length. The new design method is validated against an extensive database collected from literature and is found to provide more accurate and reliable results.

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Due to the practical advantages over traditional input-output testing, operational or output-only modal analysis is receiving increased attention when the modal parameters of large civil engineering structures are of interest. However, as a consequence of the random nature of ambient loading and the unknown relationship between excitation and response, the identified operational modal parameters are inevitably corrupted by errors. Whether the estimated modal data is used to update a finite element model or different sets of modal parameters are used as a damage indicator, it is desirable to know the extent of the error in the modal data for more accurate response predictions or to assess, if changes in the modal data are indicative of damage or just the result of the random error inherent in the identification process. In this thesis, two techniques are investigated to estimate the error in the modal parameters identified from response data only: a perturbation and a bootstrap based method. The perturbation method, applicable exclusively to the correlation-driven stochastic subspace identification algorithm (SSI/Cov), is a two stage procedure. It operates on correlation functions estimated from a single set of response measurements and, in a first step, the perturbations to these correlation function estimates need to be determined. A robust, data-driven method is developed for this purpose. The next step consists in propagating these perturbations through the algorithm resulting in an estimate of the sensitivities of the modal data to these perturbations. Combining the sensitivities with the perturbations, an estimate of both the random and bias errors in the SSI/Cov-identified modal parameters is found. The bootstrap technique involves creating pseudo time-series by resampling from the only available set of response measurements. With this additional data at hand, a modal identification is performed for each set of data and the errors in the modal parameters are determined by sample statistics. However, the bootstrap itself introduces errors in the computed sample statistics. Three bootstrapping schemes are investigate in relation to operational modal analysis and an automated, optimal block length selection is implemented to minimise the error introduced by the bootstrap. As opposed to the perturbation method, the bootstrap technique is more versatile and it is not restricted to correlation-driven operational modal analysis. Its applicability to the data-driven stochastic subspace identification algorithm (SSI/Data) for error prediction of the SSI/data-identified modal data is explored. The performance of the two techniques is assessed by simulation on simple systems. Monte-Carlo type error estimates are used as a benchmark against which the predicted errors in the modal parameters computed from a single response history from both techniques are validated. Both techniques are assessed in terms of their accuracy and stability in predicting the uncertainty in the operational modal parameters and their computational efficiency is compared. Also, the performance of the bootstrap and the perturbation theoretic method is investigated in hostile ambient excitation conditions such as non-stationarity and the presence of deterministic components and the limitations of both methods are clearly exposed.

There is a lack of practical decision support tools useful for a rapid assessment of the potential of ecosystem services when retrofitting permeable pavements in urban areas that either feature existing trees or should be pla nted with trees in the near future. There is also a need for a geospatial decision support tool for different professions such as drainage engineers and urban planners, which is useful for a quick assessment of the potential of ecosystem services when retr ofitting sustainable drainage systems ( SUDS ) in urban areas Therefore the aim is to develop a decision support tool for choosing the best possible options for the retrofitting of su stainable urban drainage system techniques using novel ecosystem service variables and modify it to include a reflection of the confidence level of the assessor to minimise uncertainty , and weighting factors that will reflect the pr ofessional background of the stakeholder s to reduce professional bias . This tool was developed and used to assess 100 sites in Greater Manchester with retrofitting potentials including Brownfield sites . The introduced weighting factors helped to narrow down the choices further. Since the retrofitting of SUDS , especially permeable pavements , and other urban development projects usually involve areas where there are already existing mature trees, further studies were carried out on the damage characteristics of urban tree species on urban structures including permeable pavements, impermeable pavements, kerbs, roads and retaining walls. This was conducted on a different 100 sites also in Greater Manchester. Further studies were also carried out about public acceptance of the urban tree species using pictures taken of trees from the Westonbirt N ational Arboretum. The result s of the ‘ecosystem service’ approach were compared with those of traditional ‘community and environmental ’ approach developed by CIRIA. A comparison with the traditional approach of determining community and environment variab les indicates that permeable pavements are generally a preferred SUDS option regardless of the professional perspectives . The introduced w eighting factors made the tool lend itself to be used by stakeholders of varying professional backgrounds. The results of the comparison of the different approaches showed that the ‘ecosystem service’ approach gave a rather more thorough and precise assessment and will give a less misleading choice of SUDS techniques. In comparison to common public opinion, sta tistically significant differences between social scientists and the general public for the estimation of land costs using the non - parametric Mann - Whitney U - test were found. It was also surprising to find no significant differences in the estimation of hab itat for species by civil engineers and xviii ecologists. Permeable pavements combined with urban trees received relatively high scores, because of their great potential impact in terms of water and air quality improvement, and flood control, respectively. The r esult of the assessment of damages to structures by urban tree species revealed that Norway maple, Lime, Common Ash and Sycamore dominated Greater Manchester, and showed that certain tree species are better suited for certain structures either beca u se of the damage or the nuisance that the trees cause . Impermeable pavements were subject to the highest number of damage from trees (44%), followed by permeable pavements and kerbs (22% and 19%, respectively). Trees planted close to impermeable pavements will c ause more damage to the structure compared to those planted close to permeable pavements under the same conditions. Wild cherry, large leaved lime, horse chestnut and hawthorn may are the best recommended trees for use alongside most roads and SUDS structu res as they have least potential to damage structures. However, horse chestnuts produce lots of litters with their conkers. From aesthetics point of view, sycamore was the most aesthetic tree all - round the year . This study therefore suggests best tree spec ies for permeable pavements and other related structures, and its outcomes are likely to lead to more combined permeable pavement and tree systems in the urban landscape, which are beneficial for humans and the environment. It will help urban developers in choosing the most suitable trees for the right urban environment. It will also help to save money in maintaining infrastructure such as roads and pavements. Keywords : Sustainable urban drainage systems; Ecosystem services; Permeable pavements; Expert system; Different professions; Stakeholders; Uncertainty; Urban trees; Urban structures, Structural damage.

The aim of this doctorate is to investigate an alternative to petroleum based thermal insulations, by using natural and recycled materials. The methodology used is centered on the use of the basic ingredients of waste animal fats, waste oils and a potash derived lye mixture, combined to create a crude soap. This soap is aerated to produce a lightweight structure that is capable of preventing or reducing heat transfer between areas of differing temperatures. Experimental testing reveals that this non-toxic product can be strengthened, made waterproof, vermin proof and fire retardant, whilst the results from the thermal testing laboratory confirm that aerated soap insulation functions as a moderate performer. The step-by-step experimental methodology applied, alongside the thermal conductivity and resistance results contained within this thesis, can be used as a gauge for future potential improvements to build from. Currently there are gaps in knowledge and practice with regards to environmental thermal insulation. There are other environmental insulations, but more research needs to be initiated regarding recyclable, biodegradable, renewable and organic components and ingredients within the insulation make-up. Industry trends are to improve the better performing petroleum insulations, whilst seemingly unwilling to compromise on environmental problem relief. This doctorate provides suggestions on how to reduce some of the environmental problems by replacing or diluting the toxic elements of petroleum insulation. Soap insulation is unique and as such makes a significant contribution to knowledge. This uniqueness is evidenced through the literature review and the systematic investigation of the research topic. The awarding of a worldwide patent on soap insulation protects the manufacture of thermal insulation comprising of solid aerated soap panels, derived from animal fats and lye. This idea of combining basic soap ingredients, then aerating the mixture to create thermal insulation is new and as such contributes to new knowledge. The publishing of a journal paper titled “Can Soap be a Sustainable Alternative to Petroleum-Based Thermal Insulation?” in the journal of Structural Survey. (Read & Arayici, 2015) emphasize the contribution of this research. Read & Arayici, (2015) describes the ingredients used, the manufacturing process and the improvement measures taken to create the soap insulation. Publishing is one method of making this research known to the global community. Academics can then engage with fellow academics or collaborate with industry to further this research or to commercialise this knowledge. Aerated soap research can widen the understanding of possible new alternative thermal insulation ideas. This creates a small yet original and significant opportunity to reduce the associated carbon footprint and environmental costs accrued each time that petroleum insulation is produced.