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The normal impact, penetration of both projectile and fastener into soils, rocks, and concrete at low velocities has been investigated using theoretical, experimental, and numerical approaches under axisymmetric conditions. The projectile penetration theory is developed on the basis of the existing cylindrical cavity expansion theory with target materials approximated by compressible locking behaviour in a hydrostatic state and elastic-plastic, linear strain- hardening behaviour in a shear state. This theory is one-dimensional with respect to wave propagation in a radial direction. Impact penetration experiments have been performed using a cartridge-operated tool firing the steel fasteners into sandstone and concrete targets. The associated pull-out problem has also been studied. Damage to both fastener and target caused by the impact penetration is assessed using an optical microscope. Finite element programs have been employed to investigate the penetration process of the projectile, and eventually to simulate the process of fastener penetration. The dependency of the penetration process on impact velocity, projectile nose shape, projectile-target interfacial friction, and target material properties have been studied for a variety of impact conditions. Comparisons of results obtained from all three approaches are made for cases in which data are available. Agreements reached are reasonably good.

This thesis describes the design of a brush robot for earthquake rescue and for traversing pipes with varied cross sectional shape. Earthquake rescue is a very dangerous, difficult and challenging task, in which emergency services rescue people who are trapped in man-made structures, such as collapsed buildings after an earthquake. The building collapse may have been caused by natural or man-made events. This technology is also applicable to tunnel collapse and land slips. The focus of this work is finding the location of victims and provision of primary life support and communications. To illustrate the concept of the robot, the thesis first discusses the current development of rescue robots and pipe robots. Then the thesis focuses on the description of a brush based pipe robot, developed by the University of Durham, which would be used as the basis of an earthquake rescue robot. The concept of the robot was illustrated and compared with other current rescue robots and pipe robots. After outlining the advantages of this robot concept, a robot body shape change theory was proposed and theoretical simulations were used to verily the practicality of the robot shape change theory. The thesis also illustrates the design of the working principle and design of a robot sensor, which was subsequently used in the robot shape change experiments. The robot body shape change experiments and the experimental results are described and discussed. The experimental results illustrate the robot concept and support the robot body shape change theory. Chapter 6 focuses on the brush unit traction investigation, bristle theory and mathematical model. Furthermore, the bristle theory and mathematical model were used to explain the variation of traction force in the traction experiments.

This research examines the importance of environmental factors in the choice, promotion and implementation of flood defence schemes in England and Wales. It focuses on the attitudes of National Rivers Authority (NRA) engineers and floodplain residents to low-frequency flood events and investigates the role of NRA engineers in influencing, the choices of floodplain residents. The theoretical focus includes an examination of the appropriateness of the dominant (North American) hazards research paradigm as an explanatory model in the British context and the development of a conceptual model applicable to this socio-political and cultural milieu. The research extends existing, primarily quantitative, research designs to include more qualitative approaches which provide descriptive richness and context beyond that afforded by quantitative data alone. The quantitative and qualitative studies of floodplain residents show environmental factors to be an important influence on their attitudes to proposals for flood hazard mitigation and to existing flood defence schemes. This is conceptualised as a 'risk-environment trade-off. The case studies of floodplain residents further identify an unmet information need concerning both flood risk and flood defence. The qualitative study of NRA engineers highlights the differences in perception and attitude between engineers and residents to flood risk, flood defence, public consultation and environmental factors. It underlines the complexity of the interactions which occur between individual, institutional and societal levels. The research concludes that the dominant paradigm model is inappropriately focused at the individual level and does not take sufficient account of institutional and structural influences. Furthermore, the concentration on choice rather than constraint ignores the social conflict and self-interest of actors in the decision-making environment. The research suggests that a systems approach is inadequate for dealing with the complexities of flood hazard mitigation.

In this thesis work to improve the Transport and Road Research Laboratory (TRRL) frost heave test is described along with a new indirect method of predicting the frost susceptibility of granular material. To determine the optimum TRRL test conditions temperatures in the Nottingham University cold room and prototype Self Refrigerated Unit (SRU) were automatically monitored. In a typical trial several thousand temperatures were recorded. These were reduced to just three independent parameters, each of which quantified a particular feature of the temperature regime. Temperature fluctuations in the water bath of the prototype SRU were excessive and so an improved Mk3 unit was developed . Road sub-base aggregates covering a wide variety of geological types and grading were tested. These had the same heave after 250 hours freezing in the Mk3 SRU and the cold room, at least within the working range. Rigorous statistical analyses revealed that frost susceptibility could be judged with equal precision after only 96 hours freezing. The variability of heave was the same in both units. This variability was attributed to intrinsic differences between nominally similar specimens. It is intended that a 96 hour Mk3 SRU, frost heave test will be specified in a new British Standard. The indirect method is based on the suction/moisture content characteristics of granular soils. These were determined using the osmotic suction technique although the specimen preparation procedure had to be improved to accommodate the hard, coarse aggregates. For all the materials tested, the volumetric moisture content at suction of pF2.5 (θ2.5) was strongly correlated with heave in the TRRL test. Calculations revealed that, for the TRRL test conditions, pF2.5 is a suction which must occur in the zone between the terminal ice lens and the limit of ice penetration. It is thought that θ2.5 reflects the overall permeability of this frozen fringe.

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This research work develops a design methodology for improving the earthquake resistance of slender portal frame structures and evaluates the performance of this kind of light gauge steel portal frame structures in earthquake prone areas through the study of designed building using a finite element approach. The design of the building was carried out for a site in Sudan for peak ground acceleration 0.23g according to the Eurocodes 3 and 8 for ductility class "Low". Two analytical techniques (i.e. Static displacement pushover and dynamic time-history), were employed to assess the behaviour of the light gauge steel portal frame structure. A new cyclic column link dissipation device is introduced to protect the structure under seismic loads and prevent buckling of frame rafter components. This link is made of back to back lipped channel cold formed steel section and dissipates energy in cyclic bending. It has a yield strength value less than the frame members, and moment resistance about 2/3 the buckling moment of resistance of the frame rafter members. The column link section is stockier than the rafters; the limiting slenderness of the columns was that for compact section. To accomplish the main objective, the potential benefits (of lightness) of utilising light gauge, steel, slender steel for the construction of portal frame buildings in earthquake prone areas, preliminary analyses of the frame with different types of links were performed using the commercially available finite element software ANSYS. The frame was analysed by nonlinear static horizontal displacements. The inelastic behaviour of the steel elements was considered using the von Mises yielding criterion and the nonlinear gemoetry were considered as large displacement and P-δ effects in the analyses.

As a result of the increasing emphasis placed on water companies to conform to the stringent performance standards in supplying demands within a constrained financial budget, the application of optimization has inevitably become an integral part of managing a water distribution system (WDS) right from the initial phase of designing a new system to the latter stage of the network where rehabilitation and upgrading works are a necessity. This also includes the on-going operation of the WDS in particular the minimization of energy costs related to pumping and storage. This thesis is concerned with the development and application of a new multi-objective genetic algorithm in optimizing the design, operation and long term rehabilitation and upgrading of the WDS.The novelty and originality of the work done as part of this research are presented next. A seamless, augmented version of the renowned EPANET 2 with pressure dependent analysis (PDA) functionality has been developed. It integrates within the hydraulic engine a continuous nodal pressure-flow function coupled with a line search and backtracking procedure which greatly enhances the algorithm’s overall convergence rate and robustness. The hydraulic simulator is termed “EPANET-PDX” (pressure-dependent extension) herein and is capable of effectively modelling networks under pressure deficient situations which the demand driven analysis based EPANET 2 fails to accurately analyse. In terms of computational efficiency, the performance of EPANET-PDX compares very favourably to EPANET 2. Simulations of real life networks consisting of multiple sources, pipes, valves and pumps were successfully executed with no convergence complications. The simulator depicts excellent modelling performance while analysing both normal and abnormal operating conditions of the WDSs. The accuracy of the generated PDA results has been explicitly validated and verified. An optimization model for the optimal design and upgrading of WDS involving both the operation of multiple pumps and the sizing and location of multiple tanks is developed. The model couples a new boundary convergent multi-objective genetic algorithm to the highly efficient EPANET-PDX simulator which, inherently,automatically accounts for the node pressure constraints as well as the conservation of mass and energy. With accurate PDA, the direct application of the standard extended period simulation enables pump scheduling and tank sizing and siting to be seamlessly incorporated into the optimization without the need for any extraneous methodology or manual intervention. The significant advantage of this model is that it eliminates the need for ad-hoc penalty functions, additional “boundary search” parameters, or special constraint handling procedures. No operator intervention, parameter calibration and trial runs are required. Conceptually, the approach is straightforward and probably the simplest hitherto. The model is applied to several benchmark networks yielding superior results in terms of the initial network construction cost and the number of hydraulic simulations required. The above-mentioned optimization model is extended to form a module for the optimal long term design, upgrading and rehabilitation of WDSs. The multi-criteria problem is set up in a multi-objective frame work i.e. to minimize the capital cost,rehabilitation and upgrading costs, whilst maximizing the network hydraulic performance. A straightforward approach for incorporating reliability measures without further complicating the optimization formulation is utilised and its robustness validated. The effect of deterioration of both the structural integrity and hydraulic capacity of pipes over time is explicitly modelled. The model automatically determines the most cost effective strategy which includes the identification of pipes to be upgraded, the upgrading or rehabilitation options and the timing for the upgrade to be implemented. A real life network in Wobulenzi (Uganda) is used to demonstrate the effectiveness of the model. Results obtained demonstrated major improvements over previous work using the classical linear programming.

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