فرزاد زادخور

Scheduling maintenance operations of railway tracks is one of the most important concerns of railway infrastructure managers. Making an appropriate decision to schedule maintenance operations can lead to the reduction of operational costs and optimal use of resources. On the other hand, all major maintenance operations must be done during possession time. Long-term blocking of the line can reduce the utilization of railway lines and cause indirect costs. In this thesis, an optimization model is presented for scheduling preventive tamping operations with the approach of reducing possession time. In the proposed model, the effect related to the cost of the unused life of the segments, the effect of previous trampling on the recovery model, and the effect of the track layout are considered, and the objective function is to minimize the operating costs, including; The cost of preventive tamping, the cost of related to possession time and the cost of the unused life of segments. This research used a genetic algorithm to solve the proposed model, and a numerical study was done to eva‎luate it. In this numerical study, four scenarios with a combination of two approaches; 1) Applying or not applying the proposed grouping policy and 2) using or not using a tamping machine with higher speed and operational capacity have been considered. The results show that using a tamping machine with a higher speed and operational capacity is generally a suitable approach to reduce the costs and possession time and reduce operating costs by 38.4% and possession time by 49.52%. However, the proposed grouping approach can reduce operating costs by 52.6% and possession time by 39.78% in some examples, along with using a tamping machine with higher speed and operational capacity.

نگهداري پيشگيرانه , زيركوبي , بهينه‌سازي , زمان‌بندي , مسدودي خط

Preventive maintenance , tamping , optimization , scheduling , possession time

Farzad Zadkhor

Dr. Jabbar Ali Zakeri