Simulation of Delay Factors in Sewage Projects with the Dynamic System Approach

Abstract

Tehran sewerage company is one of the most important urban management organizations, which project control and delays in its projects is very important. In this regard, the main question of the magnitude and effect of delays, as well as the first step in controlling the delays of each project, is to identify the causes of the time lag of the project. In order to achieve this goal, the information and documentation of sewage networks of Iran - Tehran city (except for projects of main lines of sewage and refineries) has been used during 2011-2017. This study is a descriptive study (case study, survey and library) and the community studied by observers and contractors. For this purpose, all causes of delays in urban projects are identified and classified and the impact of each factor has been determined. Then, the variables have been evaluated using the method of dynamic system and Vensim software in order to influence of factors in the incidence of delays. As a result, the research shows that the total project delays are (respectively, the highest) in the first scenario (baseline) at the end of the 24 months (project completion period) for 140 days, in the fourth scenario for 126 days, in the third scenario for 83 days and in the second scenario for 53 days and the effect of changing the identified factors is examined. In fact, in the first scenario of the full duration work (24 months), a period of 4.7 months is project delays.