عنوان مقاله [English]
The public sector has always sought to attract the private sector to partnership in the construction of infrastructure projects. The process of partnering in developed countries have less problems, while in developing countries, it faces with more serious barriers and problems. In these countries, including Iran, in spite of the proper initial reception, numerous complexities and challenges have affected project performance and also continuity partnership. This research was performed to identify the factors of environmental complexity of the projects involved public and private sectors in build, operate and transfer contracts (BOT). Multiple case study strategy was used for deep study of freeway projects. Each case was studied in detail and then the research data were analyzed by grounded theory strategy. The main product of this research is the paradigmatic model of the pathology of freeway partnership projects. In this model, the axial phenomenon was identified the private sector's dissatisfaction duo to uncertainties in cost, time and revenue of the freeway. The causal conditions were found the economical, political, and legal instabilities along with the cultural and social challenges in project environment. Context conditions were identified such as mismatches in the rules, contractual weaknesses, banking system, and finally, immaturity. Intervening conditions were obtained such as the lack of suitable market for investment projects, the influence of powerful institutions, lack of commitment and lack of a national transportation plan. According to this research, the most important outcomes of complexity were obtained increased distrust and increased ambiguity of return on investment.