عنوان مقاله [English]
There are many factors involved in the lifecycle of construction industry projects, among them, resources and consequently human relations are the main criteria of activity development, so the conflict of interest between stakeholders in projects in this industry is an obvious and challenging issue. Claims are one of the most important factors influencing the failure to meet the project objectives. The most important result of claims are delays and overflows in construction industry projects. Therefore, in this research, an attempt has been made to improve the performance of projects by ranking the causes of claims and analyzing their effects on key performance indicators. In this research, first, the factors that create claims in Water and Sewage projects and also the key factors of success in projects have been identified. Then, by distributing the questionnaire among the experts, the importance coefficient of key success factors was calculated by the fuzzy SWARA method. The weighting results showed that among the 10 key factors of success, scheduling factors, safety and health, and cost have the first to third important factors. The causes of claim creation were ranked based on the key success factors and fuzzy TOPSIS method. The results showed that the factors of delays, changes, expediting orders, overtime, changing workshop conditions and finally, ambiguity in contractual terms have the first to sixth important ranks. The results of this research can guarantee the grounds for preventing the loss of human and physical capital, as well as ensuring timely and high-quality project completion, by considering all the effective factors in the occurrence of claims.