Fuzzy Set Concepts for Evaluating Performance of Constructed Facilities

The frequent complex construction procedures of constructed facilities have led to the inevitable use of linguistic expressions in the specifications as well as during and following construction operations. The linguistic values in the specifications are generated based on the specifier's subjective judgment, while those commonly encountered during and following construction are often used for assessing the performance of the facilities. The use of such expressions has often caused their misinterpretation. This, in turn, results in inadequate performance and, subsequently, in the failure of the constructed facilities. To overcome these problems, the use of a fuzzy set concept is suggested. This concept quantifies the linguistic values and translates them into graphical models. The use of a fuzzy average rule and fuzzy algebra are introduced for integrating subjective judgments of the assessors, leading to the overall performance rating. An example using graphical display is demonstrated. Despite the innovativeness of the concept introduced for assessing the performance of constructed facilities, the method demonstrated herein is relatively simple to follow and easy to understand.