This study developed a conceptual collaborative engagement framework to overcome the challenges and contextual constraints associated with road infrastructure management in Nigeria.

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The study investigated the relationship between design and flexibility. Proposals by designers on how to incorporate the ability of buildings to accommodate changes in the requirements of the activities to be housed in buildings over time has led to a diversity of ideas regarding the relationship between suggested design variables and the achieved flexibility. Though a number of studies have been made on specific organisations and buildings, there has been no overall investigation of the general relationship between design and flexibility. To investigate this relationship it was necessary to: 1. Propose a system of measurement by which the extent of incorporation of the design variables in design proposals could be assessed (Chapters II and III). 2. Propose a system of measurement by which the extent of flexibility of buildings in use could be assessed (Chapter IV). 3. Assess the extent of flexibility achieved by the incorporation of design variables in design proposals by a study of actual buildings in use (Chapters V, VI, VII, and VIII). The study has largely achieved these objectives. It provided methods to enable objective comparison to be made between alternative design proposals in terms of the incorporation of design variables. It provided methods to enable objective comparison to be made between buildings in terms of their flexibility in use. It became apparent that the flexibility of buildings in use was related to only certain aspects of design variables or even to only certain parts of buildings. The study demonstrated that the flexibility of buildings in use is largely predictable from knowledge about their design. It showed that current ideas on flexible designs contain many factors that are redundant to flexibility. It recommends that future proposals of designing for flexibility need to be more refined than those at the present and that will enhance the effectiveness of manipulating the potential flexibility of buildings at the design stage. The main area of further research to emerge was concerned with the operationalisation of other design variables and their testing in various building types utilising the methods defined in this study.

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The stabilising wall element of the Trä8-system is a deep box-type beam/column element which is made of different types of timber composites including framing members of gluedlaminated timber (glulam) and sheathings of laminated veneer lumber (LVL). This element is used as a ―shear wall‖ in multi-storey buildings up to four storeys. To be able to optimise thecomposite stabilising element and use its maximum potential and efficiency, it is necessary to have sufficient fundamental knowledge and information about the structural behaviour and influences of different mechanical properties and geometrical parameters and dimensions of the sub-elements.In this thesis, structural analysis and design principles of the Trä8 stabilising wall element are discussed, including the early stage of erection during assembly to the final usage and residence. A list of required fundamental basic analyses are presented, including accurate deflection analysis for the serviceability limit state, local pre- and post-buckling of the LVL sheathings, global buckling as well as the lateral-torsional buckling of the stabilising element in different design situations. This thesis is then focused on deformations and local instability. For each type of structural problem, accurate, but simple and general methodology is employed to incorporate a large number of effective geometric and property parameters. In this way, a fast evaluation of the influence of different parameters is possible for a wide range of values without needing several time-consuming 3-D finite element (FE) simulations. In several cases, the accuracy and validity of the obtained solutions and formulae are examined and confirmed by comparing their results to those based on the 3-D FE simulations. First, different composite beam theories including shear effects are employed for deflection analysis of the stabilising timber element. Next, an accurate energy-based methodology isdeveloped rendering an explicit formula that gives accurate predictions for the deflection of the stabilising element within a medium range of sheathing or web thicknesses and/or stiffnesses. For weak shear webs, however, this model is not sufficient. Therefore, another new model based on the partial composite interaction theory is developed for accurate deflection predictions of the element having weak shear webs. This model contains simple but accurate formulae for deflection analysis of any similar composite box-type of element with an arbitrary range of geometry and property parameters.Next, shear buckling of the rectangular LVL-panel between the framing members are analysed using differential quadrature (DQ) numerical technique as well as an explicit analytical solution and a formula is established for accurate and fast prediction of the shear pre-buckling of the LVL. This study is extended by considering the effect of each individual lamina of the LVL as well as general orthotropic material properties using a laminated theoryand the DQ solution approach. Further, the post-buckling of the LVL panel is studied based on a simple analytical method with rotating stress fields together with the accurate 3-D FE simulations. A simple formula is then proposed for accurate prediction of the shear post-buckling resistance of the LVL-panel in the stabilising element. As a result of the thesis concerning the two main focus areas, deformations and local instability, explicit analytical formulae are presented for the design of the box-type stabilisingelement with respect to deflections including shear effects in the serviceability limit state and with respect to local shear buckling of the sheathings of the stabilising element including the post-critical area in the ultimate limit state. / <p>Godkänd; 2016; 20160217 (rasata); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Seyed Rasoul Atashipour Ämne: Träbyggnad/Timber Structures Avhandling: Structural Analysis of Deep Composite Box-Type Components With Application to a Proprietary Stabilising Timber Wall Element Opponent: Professor Per Johan Gustafsson, Avd för byggnadsmekanik, Lunds tekniska högskola, Lunds universitet, Lund. Ordförande: Professor Ulf Arne Girhammar, Avd för byggkonstruktion- och produktion, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet, Luleå Tid: Fredag 18 mars, 2016 kl 10.00 Plats: F1031, Luleå tekniska universitet</p>

This thesis considers the use of a little-known building technique: short wall anchor construction. Ignored by its users and misunderstood by many of those who observed it subsequently, the short wall anchor construction technique has proved a useful window into the perception and behaviour of early modern people and subsequent communities.

Presented in this thesis are the results from two distinct investigations on the behaviour of lightweight framing systems for buildings. One investigation concerns the characterisation of cold-formed steel sections of novel shape for the design of columns in modular construction, and this is reported in the first part of thesis. The second new investigation is for a theoretical analysis to determine the elastic critical buckling load for shear-flexible frames of fibre reinforced polymer sections. This work is detailed in the second part to the thesis. Modular 2000 Ltd. fabricated the column specimens that were characterized for the research on lightweight steel modular construction. To determine the reSistance of nine different column types a series of nominal concentric strength tests were conducted on specimens of 2.7 m length having a new E-section shape. The novelty to the shape is that it has no flat elements and is continuously curved in plan. Open E-sections are of S350 structural grade steel, are nominally 100x43 mm in plan, and have wall thicknesses of either 1.5 or 2 mm. Various bracket and enclosure combinations were the variables in the nine column types tested. These were connected to the E-sections by MIG plug-welding. Except for the 100x40x1.5 mm C-enclosure of S350, the other attachment components were of steel grade CR4, at 1.5 mm thickness. There were five column types with E-sections of 2.0 mm thickness and four with 1.5 mm thickness. Reported are the salient results from 54 strength tests, where the mode of failure was global buckling about the minor-axis of the E-column. To also determine the local buckling strength, and the effective area, a small series of stud column tests were performed on 200 mm long specimens of the 1.5 mm open E-section only. To support the understanding gained from the series of full-sized physical tests on E-columns, a programme of theoretical work is presented which is used to determine the design strengths of the column types and to predict the elastic and inelastic critical loads of a curved panel. Theory is also used to find a plasticity reduction factor for the E-section, which is required to "establish the effective area for local buckling. BS 5950-5: 1998 gives a code of practice for the design of cold-formed thin gauge sections. This current guidance is specific to steel sections comprising Simple shaped members that are of flat elements bounded either by free edges or by bends. The new results from the combined theoretical and eXperimental studies to characterise E-columns are evaluated and used to make recommendations on how SS 5950-5: 1998, and, in particular, Section 6 for members in compression, can be used with E-sections to design modular units. In the second part of the thesis the author shows how a static analysis for plane frames of shear-flexible members, written by a previous Warwick University PhD student, can be modified to calculate the elastic critical buckling load for overall instability. The modified sframe programme provides a practical analysis tool that, importantly, includes non-linearity by way of second-order P-L1 effects with shear-flexible functions and semi-rigid joint action. In conventional frame analysis shear-flexibility is ignored when members are of isotropic material (steel), and by way of a preliminary parametric study the author shows why the influence of shear deformation on reducing the buckling load of shear-flexible frames should not be neglected when the material is of fibre reinforced polymer. By studying the change in critical load in simple frame problems it is found that there is an interaction between shear-flexibility and the torsional stiffness given to the beam-to column joints. Moreover, the study on the instability of shear-flexible frames provides evidence to suggest that the relative stiffness values for joint classification boundaries are likely to be lower than those for steel frames by Eurocode 3 (BS EN 1993-1: 2005). This is an important finding for when a structural Eurocode or other code of practice is drafted for lightweight framed structures of fibre-reinforced polymer materials. Although the work presented in this thesis is from two distinct investigations the deliverables are important to the sustainable development of lightweight framing systems for buildings.

Data relating to the bids for 384 roads contracts and 190 buildings contracts and a library of individual unit prices were obtained. The normality or near normality of the distribution of bids for buildings and roads contracts is established. This allows the relationship between mean and lowest bids to be defined using normal order statistics. It also permits the application of outlier tests to be used in identifying unrealistically low bids. The average mean standardised bids of contractors have a strong negative correlation with the contractor's success ratio. This allows contractors to predict success ratios of others using their mean-standardised bids. The data required for this is not limited to the competitions in which the contractor himself enters. Contractors have different behaviour patterns, some with disproportionate numbers of high or low bids and others behave randomly. These behaviour features correlate well with the average mean-standardised bids. Graphs of the cumulative sum of (bid-mean bid)/mean bid are useful in identifying contractors who are seeking work and those who are not. These can be used to identify serious rivals for particular contracts. Contractors have different sensitivity of success ratio to changes in bid value thus indicating different market judgements. Contractors also have different trends within their standardised bids to contract value. This only affects success ratios in extreme cases. Designers have accuracies of standard deviations of 16.63% and 20.14% for predicting the lowest bid of buildings and roads contracts respectively. Price models based on multiple regression analysis produce similar accuracies for comparable construction works. The tender price prediction system developed, based on a library of, untt prices and inflation indices achieved a standard deviation of 8,30% in predicting the mean bid and 11.08% in predicting the lowest bid for roads contracts. This could be improved with more data in the price library but nevertheless is a substantial improvement on the results achieved by designer's estimating.

This thesis examined the potential sound insulation benefit by using damping material to absorb vibrational energy along its transmission path. Statistical Energy Analysis (SEA) was used to evaluate the effect on system performance of adding damping globally, as well as its influence on individual transmission paths. Nine different theoretical models were studied using both bending only and three-wave SEA models to predict the system behaviour in different frequency regions. The results suggest that global damping treatment generally increases the sound insulation in buildings. Initial increases in the internal loss factor (a term used in SEA to describe material damping properties) were found to provide significant initial improvements in sound insulation and flanking paths as opposed to direct paths were found to benefit more from damping treatment. A simple approximation was proposed to predict the damping benefit of paths of specific order without the need to run a full SEA model. In the presence of heavily damped structural element, where SEA is less likely to provide accurate prediction, a forward ray tracing algorithm was proposed as a supplement. It enables one to predict the energy transmission through a heavily damped component coupling two or more lightly damped components (or SEA subsystems). The energy distribution along the edges of the damped component was studied. The contribution from the direct field was found to dominate the incident energy and resulting transmission, especially in areas close to the source when damping is high. Different passive damping treatment techniques were reviewed as well as the theoretical damping level that is achievable as a guidance for theoretical and experimental validation. Several damping measurement techniques were studied and experimental validation of the ray tracing code was undertaken.