Development of Methodology for Transportation Fleet Structure Formation

Abstract

The paper proposes a methodology for transportation fleet structure formation based on the determination of the standard size fleet by carrying capacity using the criterion of the cost of transportation of 1 ton of cargo, which will be expedient if the number of shipments per day exceeds three times the estimated number of the model range of cars. At a lower intensity of daily shipments, it is necessary to form a standard size range of a vehicle fleet on the basis of a repetition of independent tests. The paper proposes a method of forming the structure of the fleet of vehicles based on determining the size of the fleet using the criterion of the cost of transportation of 1 ton of cargo, which is appropriate if the number of shipments per day exceeds three times the estimated number of cars. With a lower intensity of daily shipments, it is necessary to form a standard size range of the fleet on the basis of repeating independent tests.It has been established that the value of the coefficient of static use of the vehicle's carrying capacity is influenced by the number of intervals for dividing the series of carrying capacity, their length and uniformity, as well as the distribution law of the random value of the item. Violation of the uniformity of the intervals of the series of the carrying capacity of the car, the value of the coefficient can deviate from the average to 6.2% An increase in the number of intervals in a number of carrying capacities of vehicles from 2 to 3 contributes to a rapid increase in the coordination of the density of distribution of the batch volume and shipment to the structure of the vehicle fleet in terms of carrying capacity and is characterized by an increase in the coefficient of compliance on average from 0.65 to 0.75. An increase in the range of carrying capacity up to interval 5 increases the value of the compliance coefficient to 0.8, a further increase in the intervals causes an inversely proportional increase in the compliance coefficient. An increase in the number of car models from 1 to 3 causes a decrease in the cost of transportation in the range of 8% - 11.3%, depending on the degree of use of the vehicle fleet. Further expansion of the model range to 7 units practically does not affect the cost of transportation, and then its growth is observed due to an increase in the duration of downtime while waiting for the proper consignment. It was revealed that an increase in the average weight of a shipment by 2.3 times causes a decrease in the cost of transportation 1.79 times, and with this decrease in the weight of a shipment, an increase in the intensity of growth in the cost of transportation is observed.