Aleksandr Dmitriev
The Saint Petersburg State University of Architecture and Civil Engineering has a newborn PhD of Engineering Sciences. The degree was awarded to Aleksandr Dmitriev, Director of the Smart Labor training site and Assistant at the Department of Technosphere Safety at the Faculty of Civil Engineering.
The dissertation defense took place on 26 November, 2025, at the Volga Region State Technological University (Yoshkar-Ola). The dissertation council reviewed the work on the topic "Justification of the wheeled-tracked tractors parameters for low-volume logging."
The Path to Defense
According to Aleksandr Dmitriev, preparing for the defense was an important and challenging stage in his professional development: "It's impossible to prepare perfectly for such work—every dissertation committee member has their own opinions and questions. But I consider the defense a success: the questions were interesting, and I was able to answer them well."
Work on this topic took approximately five years—from the initial scientific ideas to the completed study and thesis defense. During this time, scientific articles were published, calculations were conducted, and experimental studies were held.
Relevance of the study
The dissertation addresses the pressing issue of logging equipment's impact on soil cover. Today, approximately 85% of Russian logging companies are small and medium-sized, unable to afford expensive specialized equipment and relying primarily on agricultural tractors.
Such equipment, particularly those from the Minsk Tractor Plant, is widely used due to its affordability and ease of maintenance. However, in forested conditions—stumps, fallen trees, and deep snow—its maneuverability is reduced and the load on the soil increases, damaging the ecosystem.
Aleksandr Dmitriev developed a mathematical model of a wheeled-tracked propulsion system, which retains wheels at the front and installs a track module at the rear. Increasing the ground contact area allows to:
- reduce soil pressure;
- reduce environmental damage;
- improve vehicle maneuverability;
- increase traction.
The theoretical calculations were confirmed by laboratory experiments using soil stamping tests. The study also provides a business case for the system's implementation: modernization requires minimal investment but can significantly improve the efficiency of small logging operations.
Prospects for implementation
The concept of a wheeled-tracked propulsion system is well-known worldwide, but its application in low-volume logging and comprehensive mathematical justification of its parameters have not previously been conducted. The developed model can serve as a basis for further research and practical implementation at enterprises in the industry.
The results of the dissertation are publicly available and can be used by companies for independent calculations and equipment modernization.
The scientific path and mentorship
Aleksandr Dmitriev emphasizes that a supervisor plays a key role in scientific development. He expressed gratitude to his mentor, DSc in Engineering Olga Kunitskaya, noting that the combination of professional support and personal motivation serves as the foundation for a successful defense.
Speaking about students and young researchers, he advises treating a dissertation as a long-term project that requires systematic work and patience: "The main thing is not to give up when you feel like putting it all off. It's part of the journey. It takes time, planning, and an understanding that it's a long process."
New professional opportunities
Aleksandr Dmitriev currently works as an Assistant at the Department of Technosphere Safety at the SPbGASU Faculty of Civil Engineering and heads the "Smart Labor" training site. Earning his academic degree opens new professional prospects and the opportunity to compete for higher positions.
The university staff congratulates Aleksandr Dmitriev on the successful defense of his dissertation and wishes him continued scientific achievements, the implementation of research projects, and new professional heights!