The aim of the work was to study the effect of additive concentration on changes in the adhesive and cohesive strength of bitumen. To evaluate the effectiveness of modifiers in the composition of binary and triple bitumen systems in relation to mineral fillers of two grades, the method of determination of the adhesive efficiency and thermodynamic calculations of adhesion and cohesion work were used. The following compounds were used as additives: AS-2 synthesized from the oil refining waste and AG-4I (waste sealing liquid). Adhesion–cohesion processes in modified bitumen systems are limited by the wetting effect of crushed stone and the intensity of intermolecular forces in the condensed phase of the binder. In the binary compositions, the addition of modifiers into bitumen significantly improves the cohesive strength and adhesive efficiency in relation to crushed stone. The introduction of AS-2 into bitumen compositions with AG-4I increases adhesion efficiency and thermodynamic work of adhesion in relation to the filler surface. The adhesion efficiency and thermodynamic work of adhesion in the “bitumen-AG-4I-AS-2” system reach their maximum at C_AG-4I = 3.0 g/dm³ and C_AS-2 = 1.5 g/dm³. In these concentration modes, the composition ensures maximum increase in adhesion efficiency (A_KS = 65.18%; A_KA = 48.11%) and the greatest increase in thermodynamic work of adhesion (W_A(KS) = 15.79 mN/m; W_A(KA) = 14.13 mN/m).

In systems based on bituminous film-forming agents, the adsorption of a surfactant AC-1 at the interface with air and aluminum powder has been studied. The effect of temperature, quantitative contents of the film-forming and initial surfactant concentration on the parameters and mechanism of AC-1 concentration on the interface has been established. The equilibrium indicators of the adsorption of surfactant AC-1 at the interface between the film-forming agent and air were determined (limiting adsorption Г∞, thickness of the adsorption layer δ of the surfactant AC-1 group, landing area S of the functional group of AC-1 surfactants). A decrease in Г∞in 1.5-2.0 times (0.91∙ 10-5mol/m2 with Ĉs = 1.78) and δ (2.80∙10-9÷3.00∙10-9 m) with an increase in temperature from 280 to 310K and solvent concentration up to Ĉs = 1.78. The area S of the occupied amino group in the adsorption layer was 8.50 ∙ 10-20÷10.00 ∙ 10-20 m2. The value of the resulting thermal effect (ΔН) for bituminous compositions with Ĉs = 1.17÷1.78, regardless of the surfactant content, is plus 38-40 kJ/mol;for compositions with a solvent content of 1.78 (ĈSAA = 0.06) with an increase in temperature from 300 to 313 K, there was a decrease in the resulting adsorption index by 1.0 ∙ 10-6mol/m2 and ΔH to a level of 20÷1.5 kJ/mol2.A proportional increase in the adsorption of AC-1 on aluminum powder from the initial concentration of surfactants and an insignificant decrease in the adsorption index in systems more concentrated in bitumen were established.