Decision-making in civil engineering systems

The synthesis of optimal designs and decisions in complex civil engineering systems has assumed great importance in the face of increasingly limited resources. Uncertainty and competing requirements have a complicating influence on this synthesis. The construction of a rationale to deal with these problems is the primary aim of this work. The assimilation of uncertainty requires an extensive study of the fundamentals of probability theory and leads to the maximum entropy formalism for generating prior probability distributions from incomplete data. The measurement of value using utility theory is discussed and the combination of uncertainty and value is achieved in a prescription for decision-making. The advocated prescription is that of maximising the expected utility. Illustration of the rationale and its elements is given in several examples. Common sense requires that the techniques of assigning probability measures be both self-consistent and mutually consistent within the chosen prescription. This consistency is achieved. A secondary aim of the work is to demonstrate that a systems approach can lead to insights into system behaviour. This is demonstrated by some applications to granular media, The work is specifically directed at the resolution of civil engineering systems but is in accord with the general theory of decision-making and comments on current differences of opinion are valid in this wider sense. The application of the rationale is not restricted, and this is reflected in the variety of the illustrations. In addition to an educative role the work offers some novel solutions to civil engineering problems. Suggestions for the future application of the rationale are presented.