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The growth of cargo transportation along the Northern Sea Route is hampered by a complex of technological, organizational and managerial problems, the solution of which requires the full attention of state bodies. In particular, the year-round operation of the NSR is extremely limited and in the winter period requires mandatory icebreaking support (according to climatologists, the navigation period free from ice only by 2040 will exceed 150 days). With an increase in freight traffic in the medium term, there may be a real shortage of icebreaking capacities and vessels of the Arctic class. A solution to the problem can be the creation of a separate Arctic fleet, which will transport between the extreme points of the NSR with subsequent overload. At the same time, there should be a clear understanding of the prospects for loading built ships with cargo and the corresponding reserves of domestic cargo, which potentially replace international volumes if necessary. It is important to emphasize that the existing infrastructure of the NSR is still limited (only one multifunctional deepwater port in Murmansk operates in the Russian Arctic), whereas for the transarctic navigation along the NSR, a system of deep-water ports with modern logistics and service as transport hubs is required. The attractiveness of the NSR is also reduced due to the acute shortage of realtime ice monitoring systems. At the same time, it should be understood that the growth of international transit, the subsequent construction of multifunctional ports with appropriate infrastructure and communications throughout the route will provide, in turn, a multiplier effect for other sectors of the economy, will require the involvement of new labor, which eliminates negative demographic trends in Arctic zone of the Russian Federation.

The mandatory requirement for creating high-quality asphalt concrete is the modification of the bituminous binder. Either polymers, typically SBS, or crushed vulcanizates are usually used as modifiers. Using the polymer modifier has a number of disadvantages: the poor compatibility of polymers with bitumen, the stratification of the modified binder during transportation and storage, the coalescence of the dispersed phase particles at the coating laying temperatures. The use of crushed vulcanizate as a modifier is limited due to the complexity of obtaining a particle with a micro-size and complex surface organization. By now a binary mixed powder "Polyepor-RP" based on rubber crumb and butadiene-styrene thermoplastic elastomer has been developed and obtained. It combines the advantages of both types of initial constituents and eliminates their shortcomings. The hybrid modifier is obtained by the method of high-temperature shear grinding. In addition, thanks to the use of modern rotary dispersants, the resulting hybrid modifier can be introduced into the asphalt mixture by uniformly loading it into the mixer at the closing stage of mixing, bypassing the long and energy-consuming stage of preparing the modified bituminous binder. The paper describes the comparative analysis of the rheological properties of four types of asphalt binders in accordance with the American testing system "SuperРave": unmodified bitumen of BND 60/90 grade; polymer-bitumen binder; bitumen modified with active rubber powder brand "Polyepor-A" and active binary powder brand "Polyepor-RP". It is established that the introduction of modifiers "Polyepor-A" and "Polyepor-RP" increases the resistance of asphalt pavement to the formation of ruts and increases the resistance to fatigue cracking. The introduction of the butadiene-styrene thermoplastic elastomer into bitumen has a positive effect only on the resistance to rutting. Using a hybrid modifier it is possible to obtain a rubberpolymer binder characterized by higher stability, resistant to delamination and phase separation, which will increase the durability of coatings

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Objectives. This study evaluates the effect of the modification process on the group composition of bitumen and bitumen binders containing rubber powder and hybrid modifier that is based on styrene–butadiene thermoplastic elastomer and rubber crumb. The aim of the study was to determine the presence or absence of functional groups that reflect the direction of physicochemical processes during the preparation of a hybrid modifier in rotary dispersers and during the modification of bitumen binders. Methods. Rubber powder and hybrid modifier were obtained by high-temperature shear grinding using a rotary disperser. Bitumen and modified bitumen binders were investigated via Fouriertransform infrared spectroscopy. Using the method of spectral subtraction, it was determined that during the process of manufacturing modified bitumen binders, structural changes occur in both bitumen and modifiers. During this study, the extraction of modifiers (rubber powder and hybrid modifier) in toluene was performed. Results. The quantitative analysis of changes in the group composition of modifiers before and after the modification procedure was carried out. The active polymer and structural indices were determined. The general trend of the change in the active polymer and structural indices was noted for the initial spectra of the rubber powder and hybrid modifier, and their spectra were obtained after the procedure of subtraction from the spectra of bitumen binders. Conclusions. The interdiffusion of aromatic compounds between the bitumen component and modifier particles was confirmed. On the basis of the results of the extraction of modifiers in toluene, and by taking into account the infrared spectroscopy data, it was determined that during the production of hybrid modifier during the simultaneous grinding of rubber crumb and styrene– butadiene thermoplastic elastomer, there was a chemical interaction between them.