Sustainable road surfaces: Evaluating eco-friendly additives on bitumen penetration grade

Bitumen serves as the primary binding material in asphalt concrete mixtures for road construction in Kazakhstan, where the diverse climate demands specific properties for durability and reliability. This study investigates the potential of using bitumen grade 50/70 in the southern regions of the country, known for extreme summer temperatures. While bitumen grades 70/100 and 100/130 are traditionally used, especially in the southern and northern regions respectively, there is growing interest in alternatives like grade 50/70 due to supply challenges and increased demand. However, concerns about its structural integrity under high thermal stress necessitate further analysis. The research compares the performance of 50/70 and 70/100 bitumen grades through laboratory tests focusing on penetration, softening point, viscosity, and adhesion. The goal is to assess the feasibility of 50/70 bitumen for road construction under the unique climatic conditions of southern Kazakhstan and to explore modifications for enhanced performance. The findings will contribute to optimizing bitumen