published_or_final_version / Real Estate and Construction / Master / Master of Science in Construction Project Management

published_or_final_version / Real Estate and Construction / Master / Master of Science in Construction Project Management

published_or_final_version / Business Administration / Master / Master of Business Administration

published_or_final_version / abstract / Civil Engineering / Doctoral / Doctor of Philosophy

published_or_final_version / abstract / Real Estate and Construction / Doctoral / Doctor of Philosophy

published_or_final_version / Real Estate and Construction / Doctoral / Doctor of Philosophy

published_or_final_version / Real Estate and Construction / Doctoral / Doctor of Philosophy

This dissertation is concerned with the future of the construction industry in South Africa and the ability to improve. Continuous growth is predicted through to the year 2015 and beyond, it is considered that to meet this challenge the South African construction industry must achieve substantial improvement and change. South Africa is a developing nation with ambitious objectives to improve social development and growth through delivery of infrastructure and other areas including, municipal development, hospitals, roads, water, electricity and government facilities. It is essential that South Africa has a construction industry that can develop capability and capacity to achieve sustainable growth. Current management thinking acknowledges that the best management and production principles are transferable. This is not a new concept or proposal, early management and production theorists and applicators such as Frederick Taylor, Frank B Gilbreth and Henry Ford all held the view that best practice techniques are transferable in application. By researching and presenting current successful management and production practices it intends to identify principles that can be adopted for change and improvement by the South African construction industry. A current general review of the South African construction industry has been undertaken to place it in context regarding the adoption of these best practice principles. The research will adopt a qualitative approach; it will be subjective and contain descriptions of techniques, people interactions, observations and assumptions. The principles addressed in this research are Benchmarking, Lean Production and Supply Chain Management; they have been selected as current best practice and as having significant use and proven continued success. They are presented in a format to allow understanding of the principles now developed and to illustrate via existing case studies, successes in application. Conclusions are made on individual aspects, on common core practices existing in all three principles and the current state of the South African construction industry. Recommendations are made and further areas of research suggested. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2007.

Planning, estimating and control management functions as performed by Portuguese construction companies were studied. For this purpose, inquiries were made into the way a set of Portuguese contractors carried out these tasks, with special reference to planning, estimating and the preparation of data for control during the pre-contract stage. There is a lack of integration among those functions in the current practice of companies surveyed. This is a problem that companies would like to see solved. Data systems analysis was used to tackle the problem. It was concluded that there is no functional dependency between planning and estimating in most construction projects. This is especially due to the form in which. data is structured in the basic documents currently used for those functions (the bill of quantities for estimating and the construction programme for planning). A possible integrated approach to planning and estimating is suggested by considering construction works assigned both to the items of the bill of quantities and to the activities of the construction programme. This facilitates the preparation of data for control on site because costs and time are closely related in this approach. A model for the integration of planning and estimating management functions during the pre-contract stage of construction projects is presented. The model also enables one to achieve efficient preparation of data for control on site. Computer support for the model is also presented. This is based on a Database Management System which provides for an adequate environment for the model. The model was tested in some Portuguese construction companies, and led to satisfactory results. Those companies highlighted the advantage of building up the model upon a relational database which makes data manipulation and retrieval easier and allows for integration among management functions.

The main concern of a construction client is to procure a facility that is able to meet its functional requirements, of the required quality, and delivered within an acceptable budget and timeframe. The cost aspect of these key performance indicators usually ranks highest. In spite of the importance of cost estimation, it is undeniably neither simple nor straightforward because of the lack of information in the early stages of the project. Construction projects therefore have routinely overrun their estimates. Cost overrun has been attributed to a number of sources including technical error in design, managerial incompetence, risk and uncertainty, suspicions of foul play and even corruption. Furthermore, even though it is accepted that factors such as tendering method, location of project, procurement method or size of project have an effect on likely final cost of a project, it is difficult to establish their measured financial impact. Estimators thus have to rely largely on experience and intuition when preparing initial estimates, often neglecting most of these factors in the final cost build-up. The decision-to-build for most projects is therefore largely based on unrealistic estimates that would inevitably be exceeded. The main aim of this research is to re-examine the sources of cost overrun on construction projects and to develop final cost estimation models that could help in reaching more reliable final cost estimates at the tendering stage of the project. The research identified two predominant schools of thought on the sources of overruns – referred to here as the PsychoStrategists and Evolution Theorists. Another finding was that there is no unanimity on the reference point from which cost performance could be assessed, leading to a large disparity in the size of overruns reported. Another misunderstanding relates to the term “cost overrun” itself. The experimental part of the research, conducted in collaboration with two industry partners, used a combination of non-parametric bootstrapping and ensemble modelling with artificial neural networks to develop final project cost models based on about 1,600 water infrastructure projects. 92% of the validation predictions were within ±10% of the actual final cost of the project. The models will be particularly useful at the pre-contract stage as they will provide a benchmark for evaluating submitted tenders and also allow the quick generation of various alternative solutions for a construction project using what-if scenarios. The original contribution of the study is a fresh thinking of construction “cost overruns”, now proposed to be more appropriately known as “cost growth” based on a synthesises of the two schools of thought into a conceptual model. The second contribution is the development of novel models of construction cost estimation utilising artificial neural networks coupled with bootstrapping and ensemble modelling.