A Systems approach to construction productivity

Abstract

Abstract : This thesis describes research undertaken to investigate the possibility of using systems to model productivity in construction. In particular it concentrates on the use of systems dynamics and project level productivity. Early chapters review writing in the main areas of interest. In particular they describe work in construction productivity: how it is defined and measured and what, in the opinions of researchers, are the factors that affect it. They also describe systems theory and systems modelling, concentrating on systems dynamics but including an explanation of soft systems methodologies and how they might be applied to improve productivity. The literature identified 34 factors affecting productivity and the thesis describes work carried out to quantify the importance of these and the interactions between them. It was demonstrated that realistic modelling could be achieved using only 5 factors with the rest being combined into a sixth general factor. The factors recognised as important form the basis of a systems model whose development is described. In this the relative effects of the factors on productivity are taken from the data collected and used cumulatively to demonstrate an overall effect. A description of how the system model can be used by management on construction projects to develop strategies that can help in improving productivity is provided. It suggests that investment in planning and control have most benefit on project productivity and that investments in safety, motivation and reduction of disruptions are beneficial. The model includes coefficients produced from analysis of subjective and qualitative views. The results are therefore relative and it would be necessary to validate and calibrate the model for quantitative use in practice. Suggestions for doing this are included.