Y Mahmoudzadeh. - Project and Construction Management Department, school of Architecture & Urban Planning, University of Art, Tehran, Iran.
b Barmayehvar. - Project and Construction Management Department, school of Architecture & Urban Planning, University of Art, Tehran, Iran.
h Jabbarzadeh. - Faculty of Architecture & Urban Planning, Tabriz Islamic Art university, Tabriz, Iran.

While the complexity of construction projects is increasing, the acceleration of economic, technological, social, and environmental changes challenges managers and policymakers with a strong need to learn and investigate the factors affecting projects. Most of the current problems are unintended side effects of our previous decisions. This study aims to examine various influencing factors and interactions between them to help construction managers make better decisions. At first, critical factors of delay and cost overruns in construction projects were identified through a literature review. Then, a system dynamics approach was developed for modelling continuous variables, including causal loop diagrams and stock-and-flow diagrams. Next, a quantitative model was developed using mathematical equations in the form of productivity and rework subsystems. The results of this study can help project managers to know and understand more deeply the interactions between the influential factors of the project.

Construction Management; System Dynamics; Decision-making; Delay; Cost Overrun