Heuristic Reasoning and the Application of the Concept of Fuzzy Decision Variables in the Quantitative Risk Analysis of Construction Projects in Nigeria

摘要

The study has utilized heuristic reasoning and the concept of Fuzzy Decision Variables in orderto undertake the risk analysis of a proposed construction project in a selected domain Theobjectives included determining the sources of risks, obtaining the Fuzzy Decision Variables bydeductive reasoning, identifying the types of risks prevailing in the project and the utilization offuzzy set analysis in order to estimate the possible magnitudes of the risks. Five completedprojects were analysed. For each project , a breakdown of the final contract sum intovariations, remeasurement of provisional quantities, nominated subcontractors’ accounts,nominated suppliers’ accounts, loss and expense caused by disturbances of regular progress ofthe works, fluctuation in rates of labour and prices of materials was undertaken in order toderive the sources of risks, the Fuzzy Decision Variables and the subsequent risks. Fuzzy setanalysis was used to calculate the possible magnitudes of the risks. Heuristic reasoning andfuzzy set analysis could be used in a composite framework to undertake the risk analysis of aproposed project in a selected domain.