The properties of asphalt mixtures and the quality of their execution are key factors for their service life and durability in the pavement structure. This research aims to study the effect of deicing chemicals (sodium chloride, NaCl) on asphalt mixtures in laboratory conditions to know the changes in properties when the samples were loaded with a different number of freeze–thaw cycles. The behavior of the standardly used asphalt mixtures and bitumen binders was verified by the exposure to sodium chloride solution (20 g/L NaCl). In the first part of the experiment, penetration, elastic recovery, and softening point tests were performed for paving grade bitumen 50/70 and 70/100, and polymer-modified bitumen PMB 25/55-60. Furthermore, asphalt concrete (AC 11) mixtures with different air voids were subjected to 25, 50, and 75 freeze–thaw cycles to determine the effect on the service life of the pavement structure. Following the Czech standard, CSN 73 6161, and the TP 170 regulation for the design of asphalt pavements, the Marshall test and the stiffness modulus were determined for all asphalt samples. The obtained results show a negative effect of freeze–thaw cycles on the properties of asphalt concrete surface course mixtures and bitumen.

The paper summarizes past experience in the use of reclaimed material in road construction layers according to various technologies applied in road construction. The recycling of asphalt pavements is a standard widely applied and established in road practice for many years. There is strong interest to increase the use of recycled materials in asphalt pavements for cost and environmental reasons. The paper defines the strengths and weaknesses of individual technologies and recommends where and when the use of R-material is appropriate, economically sound and technically justified. The production of new asphalt mixes with more reclaimed material is limited by more factors in the Czech Republic. They include the regulation of the quantity of reclaimed material in the standards and technical regulations. The machine equipment of contractors for recycling is not always sufficient either.

The increasing demand for durable and sustainable infrastructure requires innovative approaches to improve asphalt mixture performance. This study investigates the use of bio-based jute fibres as reinforcement in asphalt concrete for surface layers (AC_surf 16+), with particular focus on fibre dosage and surface treatment using NaOH and tetraethyl orthosilicate (TEOS). A conventional 50/70 paving-grade bitumen was used for the reference and fibre-reinforced mixtures, while a polymer-modified bitumen (PMB) mixture was included as a control for performance comparison. The evaluated properties included air voids, stiffness (indirect tensile test, IT-CY), moisture susceptibility, and crack propagation resistance assessed using the semi-circular bending (SCB) test. The results show that jute fibres can improve selected mechanical properties, particularly crack resistance, with performance strongly influenced by fibre characteristics and surface treatment. TEOS-treated fibres demonstrated enhanced interaction with the bituminous matrix, leading to improved resistance to crack propagation compared to untreated fibres. These findings indicate that treated bio-based fibres represent a promising sustainable alternative or complementary solution to conventional polymer modification in asphalt mixtures.