Value Management (VM) is an organised effort directed at analyzing the functions of systems, supplies, equipments and facilities, for the purpose of achieving the required functions at lowest overall cost, consistent with requirements for performance, including reliability, delivery, maintainability and human factors. This structured method can also be successfully used to define the scope of a project. In the UK, the awareness of the tremendous potential and benefits of applying VM to construction projects has made some clients eager to apply this technique to their projects. There are, however, a number of problems which inhibit the use of this advanced technique in the construction industry. Qualified VM specialists, for instance, are very scarce within the industry, it is often difficult to find them to undertake proper VM studies. This research therefore aimed at exploring the feasibility of building a Knowledge-Based System (KBS) to facilitate VM implementations in the design stages of a construction project. A demonstration system has been successfully developed to illustrate the facilities which would be available to potential users in a fully developed system. A method of allocating project cost against functions of the project specified by the clients has been developed, which could expedite the processes of clarifying clients' brief and ensuring good value for money by cutting unnecessary costs and enhancing required functions. The research has also explored how KBSs can be effectively applied to "open-ended" decision-making problems in which new options may be generated during each session with the system, i.e. the study considered the possibility of letting users extend and customise the knowledge base. The system has been described as a "satisfactory and very promising system" by the UK industrial specialists.

The thesis considers the construction tender price index, an important area of construction economics, and models are developed to fit the trends in this index. Between 1980 and 1987, the UK Building Cost Index produced by the Building Cost Information Service increased at an annual rate of 6.3% compared with Tender Price Index 3.3% and Retail Price Index at 6.7% per annum. This significant disparity between Tender Price and Building Cost Index is unexpected in view of the attributed importance of input prices in the tender price formation. This suggests that other factors apart from input prices may be responsible for the trends in building prices generally. The thesis reviews the pricing strategies of construction contractors leading to the conclusion that macroeconomic factors are equally important. A univariate analysis of 24 potential indicators of tender price trends identified some variables of importance. An analysis is described of these variables using the OLS system of regression analysis. Single structural equation model of construction tender price level is developed which offer structural explanation of the movements in the index. Indicators of construction price (in real terms) produced by the structural equation were found to be unemployment level, real interest rate, manufacturing profitability, number of registered construction firms, oil crisis, building cost index, construction productivity and construction work stoppages. A Reduced-form model of construction price is developed that utilises simultaneous equation models comprising construction demand, supply and equilibrium models - the reduced-form models being generally regarded as having better predictive power than structural equations. The model is validated by comparing its accuracy with forecasts produced by two leading organisations in U.K. The out-of-sample forecast errors of the reduced-form model are 2.78, 3.58, 4.28 and 5.59 RMSE percent over 0, 1, 2 and 3 quarter forecast horizons respectively, which are better than the Building Cost Information Service (3.32, 5.29, 7.57 and 9.96 RMSE percent) and Davis, Langdon and Everest (3.21, 5.01, 7.16 and 10.41 RMSE percent).

In the UK, building maintenance makes up more than 50% of total construction output while reactive maintenance covers two thirds of the overall building maintenance projects. It was therefore found not surprisingly that reactive maintenance work receives the most complaints and gives more negative impacts on business activities in terms of time, cost, and the health and safety of the users. As this type of maintenance work is mostly carried out by firms with less than 20 employees, which constitutes 84% of the industry, reactive maintenance is hence, the major focus of this study. The aim of the research is to demonstrate how inexpensive IT and communication tools can lead to enhanced effectiveness and efficiency in the delivery of minor construction projects. Process analysis was carried out to provide valuable insights into the existing business process of reactive maintenance and also the information and communication technology that is being used by the parties involved in the process. It unearthed problems that impede the process in terms of time, cost, quality of work and the health and safety of the users. These problems can be encapsulated as poor communications between different parties, lack of knowledge sharing and poor quality of information, which often leads to longer time taken to fix a problem and incurs higher cost. A prototype online knowledge management system called "MoPMIT". MoPMIT (More Productive Minor Construction Projects through Information Technology) was developed based on these problems and the improvements required which the main idea is to bring all parties onto the online system so that they can share the necessary project information for better management of knowledge. The system allows them to communicate and share the information available to them via a common interface with pre-allocated password access as a control mechanism that restricts each user to its role. System evaluation was conducted among potential MoPMIT users and generally the results were positive. They were of the view that this system would lead to better management of knowledge, improve communication and better sharing between all parties.

Stainless and other high quality steels are used extensively in the topside construction of oil rigs. Steel is heavy, expensive and even the special grades are prone to corrosion in the aggressive marine environment. New materials are needed which are lighter, more cost effective and free from corrosion related problems. Glass fibre reinforced plastics (GRP) have the required properties but their performance in fire conditions is not known. Fire is a very real and possibly catastrophic threat. Before specifying the use of GRP components it is essential to quantify their reaction to fire. Panels and pipes to be used in fire risk areas were the components of interest, and the objectives of the research, based on experimental testing, were as follows: 1) To evaluate GRP laminates for use as structural panel skins, noting their structural and fire performance. 2)To develop incombustible, low cost cores for sandwich panels. 3) To produce sandwich panel design proposals which satisfy specified fire exposure requirements. 4)To assess the fire performance of empty and dry, stagnant water filled and flowing water filled polymer composite pipes with or without fire protection. 5) To use finite difference modelling as part of the design process for fire exposed pipes and panels. Factors of water content for hygroscopic cores and the ablation mechanism of fire exposed GRP were taken account of. 6) To assess the validity of the standard furnace fire resistance test with respect to combustible materials, and with respect to the reproducibility of results between different furnace arrangements.

It has often been recognised that planning and design can play an important role in the achievement of sustainable development of cities. However, problems still exist with regards to both a clear understanding of sustainability in the built environment and a means of evaluating it within the context of urban planning and design. This thesis has compared different evaluation methods in urban planning, both ex ante approaches and monitoring, and their philosophical paradigms. Some significant limitations are identified and discussed in the context of sustainability, such as the reductionism within many of the approaches and the lack of holism in the evaluation. The identified deficiencies provide the motivation for the development of a new framework which is able to integrate the different dimensions of sustainability in the built environment. This is based on the Cosmonomic theory of Dooyeweerd which has proved to be more appropriate than other philosophical paradigms in achieving this task. The theory is applied to the built environment for understanding sustainability and developing a framework in planning evaluation. The framework helps decision makers to critically identifSr the sustainability aspects involved in a (re)development planning project, guiding them in the evaluation on the basis of a number of problem solving methods. Some existing case studies are adopted to show the benefits of the framework in the context of regeneration programmes for cities, management policies for cultural heritage and environmental services. The resulting framework provides a significant step forward in understanding and evaluating the built environment in the context of a sustainable urban development. It also has the potential to allow evaluation of the concept of sustainability over time.

The research is divided into two parts. In the first part the structural behaviour of sandwich beams using timber-based facings and foamed plastic cores was studied. Various available theories were examined and the most appropriate theory for this type of panel was identified. In an extensive test programme the relevant properties of the constituent materials were measured and the data used in the proposed theory of structural behaviour to predict beam deflections and core and facing stresses. Corresponding sandwich beam tests were carried out on the range of skin/core combinations and the theoretical and experimental behaviours were compared. Good agreement was confirmed within the range of span/depth ratios investigated, confirming the applicability of the theory for semi-thick timber-based facings. A variety of timber based facings were investigated and those most suitable for sandwich construction were identified. This type of panel construction has many advantages but lacks the benefit of good fire resistance. The recF.iired fire resistance could be provided by a suitable core material. Part two of the research concentrated on the development of a new core material which was intended to have good structural properties at reasonable density, and to have adequate fire resistance free from the production of smoke and toxic fumes. Coated paper honeycombs were chosen for the study. The properties of the constituent materials were investigated in detail and then the structural properties of the developed cores were measured using methods drawn from national and international standards. One particular coating combination proved to be effective in terms of stiffness, fire resistance, freedom from micro cracking and strength retention at high temperature. This was based on a mixture of sodium silicate and ball clay. Cores were tested both with cells empty (to be blocked by intumescence) and with cells filled (e.g. with lightweight filler). In the best of the developed cores, shear stiffness and transverse stiffness were much higher than in normal core materials. On the basis of the test programme, panels can be designed to give a fire resistance defined by insulation of up to two hours.

There is a growing consensus that appropriate strategies and actions are needed to develop sustainable built environments and construction activity. This thesis contextualises this consensus within the broader sustainable development literature. First, the review of the literature culminates in the development of the Holographic Dynamic PSR (pressure, state, response) model as a holistic, system-orientated framework to better understand the focus of, and interaction between, stakeholders' worldviews and actions to progress sustainable development. Second, five systemically linked hypotheses are articulated to test the argument that the current body of research knowledge is not sufficiently focused and integrated to support progressive, significant and balanced sustainable development. The hypotheses are tested using built environment and construction activity specific literature, through a 'nested' research methodology comprising an interpretative philosophy, a soft systems research approach and literature review and synthesis research techniques. The thesis substantially supports the overall argument mapped out by the hypotheses, and proposes both a generic dynamic research agenda framework to progress sustainable development in general; and a UK prioritised research agenda for sustainable built environments and construction activity.

The lack of a buildability evaluation at the design stage coupled with the separation of the design and construction processes have been acknowledged to cause buildability problems on site. Normally, designers view of their task, is to develop a masterpiece which satisfies the functional requirements of a project while constructors consider their task as construction works, which need to be completed at the lowest price. No significant efforts have been made to bring the design and construction processes together to facilitate the integration of information for the improvement of the overall project performance. This study proposes an integrated framework for construction planning which is capable of exchanging information with other construction disciplines and generating planning information in an integrated construction environment. Planning data and processes were first modelled using object oriented analysis methodology, i.e. Martin (1993), where the emphasis was placed on both the data and its behaviour. This development was carried out within a general integrated framework which facilitates the integration between the various construction application across the project life cycle. The developed models highlight the importance and the role of the planning process which is vital in providing relevant information to other disciplines. Moreover, the study proposes a quantitative approach for a buildability evaluation based on the information available within the integrated environment. It evaluates the design solutions from the construction view, as outlined in the construction plan. The qualitative principles of buildability improvements were adopted to formalise this approach. A combination of weightings and scores were assigned to building elements to reflect their buildability factors. The developed data and process models, were implemented in an object oriented environment as part of a single integrated construction environment SPACE (Simultaneous Prototyping for An Integrated Construction Environment) where CONPLAN (Intelligent CONstruction PLANning for design rationalisation) is one of the SPACE modules. CONPLAN automatically generates the construction planning information and the buildability reports. The former can be dynamically accessed either through a planning package or visualised in a virtual space using a virtual reality package. The buildability reports can be either displayed in a textual or graphical format.

Property developers, investors and financiers usually have reservations about the investment performance of rehabilitated and refurbished properties.This is due to the uncertainties introduced by low rental income, higher yields and shorter leases associated with secondhand properties. This situation is thought to be changing as more and more successful schemes are reported in the property and business press. What is changing attitudes is the improved economics of refurbishment schemes. Occupiers are seeking to reduce occupancy costs after the last recession. Rehabilitated properties which can offer facilities comparable to new build but at a fraction of new build rents are therefore becoming attractive. Furthermore, recent innovations in services and communication technology is making it possible to service older properties to the same level as new buildings. This is creating investment value in buildings that might otherwise have remained unlet. Despite the improved situation, there seemed to be no formal framework to aid building rehabilitation versus redevelopment decisions in the private commercial property sector. The critical decision determinants are scattered over several publications. What this research has done is to assemble all factors within a single framework. Examining the nature of buildings, it is apparent that different groups evaluate buildings differently. To some they are symbols of prestige or image and to others they help create the environment we live in. Yet more, some see buildings as shelters and investment assets. In the private sector, the main actors that influence property development are occupiers, developers and investors. Each of these actors evaluate buildings on different criteria. This makes the building rehabilitate-redevelop decision a conflicting multi-criteria problem. The framework created by this research is therefore based on Multiattribute utility theory (MAUT). The research identified the objectives of building renewal from the perspectives of occupiers, developers and investors using the principles of value-focused thinking. The common indicators linking these objectives became the decision attributes over which utility and value functions are to be created. By the research results, the option chosen in the decision scenario described above is determined by the attributes: profit, maintenance cost, energy cost, floor to floor height, floorplate area, floor load-bearing capacity, floorplate width and on-site car parking provisions. The preferred option is the one that maximises the subjective value of the decision maker over these attributes.

Masonry arch bridges have been used throughout the world. Many thousands exist in Europe. The number of arch bridges in the United Kingdom has been estimated at 75,000 with approximately equal numbers occurring within the road and railway networks. The arch is very pleasing to the eye. Many arch bridges are listed structures so that replacement schemes are not options. In 1880 Baker was commissioned to report on the deterioration of Telford's Bridge at Over. Baker wrote, "The abutments had gradually gone over, and had been continuing to go over for sixty years. The result was that certain barbarians were actually urging the magistrates to take down the bridge...". He continued, "... cracks in the spandrels were big enough to walk through quite comfortably. It would be a disgrace to the country if they pulled down Telford's historical work and substituted a hideous iron latticebridge", (Heyman & Threlfall, 1973). Masonry arch bridges were built to carry a road, a railway or sometimes a waterway over an obstacle. A right arch bridge was used where the crossing could be perpendicular to the obstacle. In contrast, a skewed arch was built wherever the obstacle and over-road intersected at any angle other than 90°. Thus, a right arch is a special case of the more general class of skewed arch. The extent of existing knowledge of the behaviour of arch bridges is limited to the right arch in which many effects have either been omitted or have been simplified. These effects include the spandrel walls, the backfill, irregular geometry, and eccentric loading. Clearly, there is scope for an advancement of knowledge so that these effects may be considered and ultimately the behaviour of the skewed arch bridge can be described. The construction of arch bridges in Great Britain reached its zenith at around the beginning of the Nineteenth century. At this time, if conditions prevailed, there was a general desire for each new bridge to exceed the span of any that had gone before (Ruddock, 1979). However, Sejourne (1913) could only find eight structures in the United Kingdom that had at least one span with a clear opening of more than 40.0 m.