Condition Assessment of Corrosion-Distressed Reinforced Concrete Buildings Using Fuzzy Logic

A method is presented for obtaining condition index of corrosion distressed RC buildings. Method is developed using concepts of fuzzy logic and it integrates visual inspection with in situ investigations for carbonation and chloride content. Distress manifestations and repair priorities are classified. Condition is related to repair priorities through condition ratings. Repair priorities are fuzzy in nature as they are dependent on interpretation of the inspector. Questionnaire survey is prepared and responses are collected from the experts. Obtained data are used for development of fuzzy membership functions for defined repair priorities. A building can be subdivided into various elements. Observations for various distress manifestations are recorded for each element, using the format proposed. These observations are combined using fuzzy extension technique to obtain individual membership function for each element. Defuzzyfication using center of sum method provides with the combined building condition index (BCI) from elemental membership functions. Obtained BCI provides direct measure of condition and repair needs of the building. Developed methodology is explained through a case study on condition assessment of an academic building.