The Optimum Diameter Selection by Using FAHP Method for Kakareza Water Tunnel Based on Cost and Time Parameters

Nowadays tunnels optimum diameter selection is a complicated problem for designers. Different methods have been suggested for the optimum diameter selection. Once this methods is fuzzy analytic hierarchy process (FAHP) that obtains the best alternative according to the opinion of some experts. In this paper we have tried to select the optimum diameter for the Kakareza water tunnel (located in North West khoramabad). To do this we had three alternatives and five criteria. The alternatives were 2.7 m, 4.3m and 6 meter obtained based on last tunnel excavation experiences, region position and different tunneling problems. The selected criteria include blasting, ventilation during excavation, tunnel support system, tunnel construction time and tunnel construction cost. At the beginning some forms were provided, using 5 points scales, to have the experts opinions. They recorded each alternative scores for different criteria in respective tables. Applying the obtained primary data and FAHP method, we have concluded that diameter 2.7 m is the best for the Kakareza tunnelexcavation.

کلیدواژه ها:

multi criteria decision making ، FAHP ، fuzzy set theory ، TFN ، water tunnel