The Formation of a Track by the Propulsion of a Forestry Machine on the Slope of the Thawing Soil in the Permafrost Zone, Taking into Account the Effect of Solifluction

Abstract

In the Russian Federation, a significant part of the forest fund territory is located on permafrost. Many regions of the country have large reserves of mature and overmature commercial forests, and a significant part of these reserves are located in hard-to-reach places, not only due to the underdeveloped road network, but also due to the difficult terrain. Currently, the vast majority of timber harvesting in Russia is carried out using modern machine complexes, mainly including wheeled forestry machines of various layouts and purposes (harvesters, forwarders, skidders, etc.). At the same time, the problem of the negative impact on the soil of forestry machines and skidding systems based on them not only remains relevant, but becomes even more acute, since the ecosystems of mountain forests, forests on the slopes of hills, etc. are among the most vulnerable, subject to water and wind erosion. As is known, the track in the soil is formed under the influence of normal load transmitted through the contact spot of the mover, as well as under the influence of the tangential force realized by the mover when moving the machine. When lifting a machine onto a slope, the tangential tractive effort of the propulsion is required than when moving across the plain. Consequently, the intensity of track formation on the slope is higher, all other things being equal. Machine systems are known where, when working on slopes, winches are used to help machines go down and up the slope. Winches can be either separate units or units integrated into the transmission of machines. The research has shown that using winches when lifting the machine onto a slope significantly reduces fuel consumption and transmission loads, which is a consequence of a decrease in the tangential tractive effort required to move the machine, realized by the engine. Then the intensity of track formation on the slope when the machine is working with a winch is less compared to working without a winch.