Fuzzy concrete bridge deck condition rating method for practical bridge management system

摘要

Bridge management system (BMS) is a tool for structured decision making and planning/scheduling for bridge infrastructure inspection, maintenance and repair or retrofit. Any BMS is basically constructed based on data stored in inventory and inspection databases. One of the important and crucial efforts in managing bridges is to have some criteria to show the current condition of the elements of bridges based on the results from inspection data. As the results are not precise and are related to the depth and extent of the inspectors’ expertise, there are some uncertainties in any evaluation. On the other side condition of bridges are rated linguistically in many cases with some kinds of vagueness in description of the bridge element conditions. Based on these facts in this paper a new fuzzy method is introduced to deal with these shortcomings from the uncertain and vague data. The fuzzy bridge deck condition rating method is practically based on both subjective and objective results of existing inspection methods and tools. The parameters of the model are selected as fuzzy inputs with membership functions found from some statistical data and then the fuzziness of the condition rating is calculated by the fuzzy arithmetic rules inherent in the fuzzy expert system. Since one of the most proven and experienced advantages of fuzzy inference systems is the tolerability for noisy (uncertain and vague) data it is believed that this proposed system can be an alternative method for current rating indices amongst many others which are almost used deterministically.