Fuzzy system dynamic model for simulation of new rail track construction machine productivity in India

Purpose The utilization of the new track construction (NTC) machine in the dedicated freight corridor (DFC) project in India proved to be counterproductive due to various uncertain and dynamic factors. This study aims to develop the model and simulate the productivity of the NTC machine considering system dynamic factors encountered during the construction phase of the project. Design/methodology/approach The study employs a fuzzy system dynamics (FSD) model to analyse the productivity of the NTC machine. Initially, 21 variables related to the construction productivity of equipment-intensive activities are identified using exploratory factor analysis (EFA). A stock-and-flow diagram is then developed to examine the interdependencies among these variables. The FSD model integrates hard relationships via mathematical formulas and soft relationships using fuzzy measures and integrals. The model’s structure and behaviour are validated through dimension consistency, structure verification and pattern verification tests. Findings The results indicate that key system variables, such as site restrictions, weather and site conditions, unscheduled breaks and functional range, significantly influence the productivity of the NTC machine. The study also indicates the importance of human expertise, operator’s experience and crew coordination skill as influencing system variables in equipment productivity. Originality/value This study provides insights in managing complex and dynamic factors affecting the productivity of the NTC machine used large-scale rail construction projects. This study offers a novel application of FSD to address productivity challenges of this special equipment in the new rail track construction projects.