Sahar Mahdinia - Department of Civil Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
Mohammadreza Tavakkolizadeh - Department of Civil Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
Amir R. Masoodi - Department of Civil Engineering, Ferdowsi University of Mashhad, Mashhad, Iran

This paper investigates the intricate relationship between sample age, cement blaine, and thecompressive strength of mortar and concrete. Specifically, it focuses on understanding how these factorsinfluence the mechanical properties of these materials at two critical time points: ۷ and ۲۸ days. Through acomprehensive analysis, this study sheds light on the evolving characteristics of mortar and concrete overtime. To achieve this, we introduce a novel predictive modeling approach based on Gene ExpressionProgramming (GEP). This innovative methodology allows us to anticipate variations in compressivestrength accurately. By incorporating the effects of both sample age and cement blaine, our GEP-basedmodel provides valuable insights into the mechanical behavior of mortar and concrete. The findings of ourresearch reveal essential correlations between sample age, cement blaine, and compressive strength. Theseinsights contribute significantly to a deeper understanding of the factors influencing the performance ofconcrete materials. Moreover, our proposed GEP-based model emerges as a robust tool for forecastingcompressive strength, offering engineers and designers enhanced capabilities to optimize concrete mixturesand design structures with superior performance and durability. Overall, this study not only advances ourunderstanding of the complex interplay between sample age, cement blaine, and compressive strength butalso offers practical solutions for improving the design and performance of concrete structures in variousapplications.

Compressive strength; sample age; cement Blaine; Gene Expression Programming(GEP).