Study On Operations Of Wagon’s Taking-out And Placing-in At Railway Technical Station

In regional marshalling station, district station and freight station, freight volumes are larger than other stations. As an important work, the quality of placing-in and taking-out shunting operation influences other assignments directly, even the work efficiency and competition of the station. So the study on placing-in and taking-out shunting is important to improve station production indexes, such as the utilization rate of locomotive, wagon’s resident time at station and train departure punctuality rate, etc.On the basis of previous research results, the placing-in and taking-out shunting problem was studied in this paper from the optimization theory and method aspects. The main work is as follows:(1) The element, classification, function and characters of the wagon’s placing-in and taking-out shunting system were described in detail which laid the groundwork for further research. From the perspective of coordination in system and cooperation with external system, several advice and ways to compress working wagon’s resident time at station were put forward;(2) The classification analysis of definite and indefinite influencing factors of wagon’s placing-in and taking-out can weaken the impact of adverse factors and improve the quality of work in the station. The discussion of the methods’ description with random variables and models can provide some reference for future research. Considering the actual work condition in station, the calculation and verification of the best placing-in and taking-out times of random arrival wagons in goods yard or in only one private line was improved by increasing the constraint conditions of locomotive’s number and workload. The improvements of indexes, such as placing-in and taking-out times, loading and unloading lines’ capacity limits and locomotive’s working time, etc. were analyzed, which indicated the computation method was more economical and reasonable, and was helpful for station to adjust the work according to the station’s personnel quality and equipment.(3) The procedure of placing-in and taking-out problem on actinoid private line was studied under the constraints of locomotive’s towing capacity, loading and unloading lines’ capacity and some special private lines’ working mode which is only delivery or retrieve. Considering marshalling and placing-in and taking-out control time windows, a concept model was established for retained and successive arrive train groups, whose optimization target was the minimum locomotive’s running cost. The placing-in and taking-out’s order, number, pattern and moment were taken as a whole in this model which is applicable to any wagon flow form and more realistic. On the premise of completing the whole work, the locomotive can help others do some other work in order to make full use of the capacity.(4) On the basis of the model, a simple and reasonable coding method was built, and solved using genetic algorithm. According to the character of the problem, the generation method of initial population was designed, and the selection, crossover and mutation operators were improved respectively, which can help the population evolve toward a favorable direction and accelerate its own convergence. Finally, a simple example was given to verify the correctness and effectiveness of the model and algorithm.