Evaluation of bridges of Mazandaran province using multi-criteria decision methods based on existing failures

The bridges with any form of structure that are designed and made with any kind of materials that are being manufactured, sooner or later, appear in their burnout effects, but in the type and extent of these exhaustions and their expansion, there are several factors such as conditions Atmospheric, flood or earthquake occurrence, increase in load over design, design quality, and type of materials affecting all of these factors, if not addressed, will lead to a reduction in the useful life of the structure. Therefore, handling bridges and timely maintenance of them will increase the useful life of the bridges. In this research, the evaluation bridges of Mazandaran province has been considered for the needs of maintenance. In order to carry out this research, firstly, the field visits of high importance bridges in Mazandaran province (more than 100 bridges have been investigated and evaluated in this research), and the failure and defect status of each of these bridges As well as the condition of these bridges against the factors such as traffic load and river bed, were studied. After conducting field visits and collecting the required results, we have studied the priority of each of the bridges in Mazandaran province regarding the need for maintenance. Also, in order to determine the amount of costs necessary for the maintenance of bridges, experts in this field were used and each bridge was evaluated separately and finally the amount of repair cost needed for each bridge was identified.