A study on the availability of applying fuzzy logic to the decision making of the arterial road route in mountainous areas

Abstract

On the projects of the arterial road, projectors have to take qualitative items and quantitative items into consideration, therefore it is difficult to decide an adequate route of road with the objectivity. In the case of the project with four proposed routes in north-eastern part of China, according to the chinese planning method, we offered three such supra-functional factors as economic index estimated by basic designing, technical index estimated by reconnaissance and difficulty at constructing and maintaining. Three factors consist of sixteen items. Five qualitative items were evaluated as fuzzy set from the answer of questionnaire. In order to include all items in consideration, we applied the fuzzy logic to the decision making of the route. Each fuzzy set consists of four such words as excellent, good, middle and bad. Applying analytic hierarchy process we calculated weights of each items within the factor and weights of each factors. The grade at the word of "excellent" under the fuzzy set were 0.219 (plan D), 0.397 (E), 0.192 (F), 0.203 (G). On the other hands, the grade at the word of "bad" were 0.590 (D), 0.264 (E), 0.599 (F), 0.461 (G). The evaluated value as the comprehensive criteria indicated that the plan E exceeded to other routes especially. The Chinese projectors also judged the plan E as the adequate route under their experiences. In conclusion, we prove that the applying fuzzy logic to the decision making of the arterial road is available and effective quantitatively.