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The haulage of timber from remote logging areas of Siberia is characterized by high transportation costs. Long stretches of unpaved logging roads, seasonal constraints (spring thaw and winter roads), and considerable distances from cutting areas to main transport hubs (50–200 km) make systematic route planning essential.

This paper proposes a mathematical model of the two-echelon vehicle routing problem (2E-VRP) adapted to timber haulage in the macro-region of the Urals and Siberia. The model incorporates variable transportation costs (truck mileage), fixed costs of using each vehicle ($c_{fix}$ = 30 000 RUB per trip), and vehicle-capacity constraints. The problem is transformed into a QUBO (quadratic unconstrained binary optimization) formulation; capacity constraints are integrated through the penalty coefficient $\lambda_{cap}$ = 500. This representation makes the model compatible with modern specialized solvers, including quantum annealers and digital annealers.

The model is tested on the real geography of the Ural and Siberian Federal Districts: 207 nodes in the logistics network, 65 customer enterprises, and 8 main transport hubs. The proposed three-stage “Feasible-First” algorithm constructs a feasible routing plan in 1.7 s and reduces total transportation costs by 69% relative to a baseline genetic algorithm. Subsequent simulated annealing further improves the QUBO objective value by 55%.

This work contains a description of the results of modeling the process of maintaining the readiness of a section of the road network under strikes of with specified parameters. A one-dimensional section of road up to 40 km long with a total number of strikes up to 100 during the work of the brigade is considered. A simulation model has been developed for carrying out work to maintain it in working condition by several groups (engineering teams) that are part of the engineering and road division. A multicopter-type unmanned aerial vehicle is used to search for the points of appearance of obstacles. Life cycle schemes of the main participants of the tactical scene have been developed and an event-driven model of the tactical scene has been built. The format of the event log generated as a result of simulation modeling of the process of maintaining a road section is proposed. To visualize the process of maintaining the readiness of a road section, it is proposed to use visualization in the cyclogram format.

An XSL style has been developed for building a cyclogram based on an event log. As an algorithm for making a decision on the assignment of barriers to brigades, the simplest algorithm has been adopted, prescribing choosing the nearest barrier. A criterion describing the effectiveness of maintenance work on the site based on the assessment of the average speed of vehicles on the road section is proposed. Graphs of the dependence of the criterion value and the root-meansquare error depending on the length of the maintained section are plotted and an estimate is obtained for the maximum length of the road section maintained in a state of readiness with specified values for the selected quality indicator with specified characteristics of striking and performance of repair crews. The expediency of carrying out work to maintain readiness by several brigades that are part of the engineering and road division operating autonomously is shown.

The influence of the speed of the unmanned aerial vehicle on the ability to maintain the readiness of the road section is analyzed. The speed range for from 10 to 70 km/h is considered, which corresponds to the technical capabilities of multicoptertype reconnaissance unmanned aerial vehicles. The simulation results can be used as part of a complex simulation model of an army offensive or defensive operation and for solving the problem of optimizing the assignment of tasks to maintain the readiness of road sections to engineering and road brigades. The proposed approach may be of interest for the development of military-oriented strategy games.