Long-term mechanical and physical behavior of rural concrete roads: A case study from Trabzon; [Kırsal beton yolların uzun vadeli mekanik ve fiziksel davranışı: Trabzon’dan bir vaka çalışması]

This study evaluates the long-term mechanical and physical performance of rural concrete pavements-defined as two-lane, unreinforced jointed plain concrete pavements constructed with a C25 mix design, an average slab thickness of 18–20 cm, serving low-to-moderate traffic volumes (<500 vehicles/day, <10% heavy vehicles), and built directly over compacted granular subgrade-using cylindrical core samples extracted from five neighborhoods in Trabzon, Türkiye: Çal, Gökçeler, Derecik, Çiğdemli, and Yolgören. Laboratory tests included compressive strength, splitting tensile strength, elastic modulus, capillary water absorption, and abrasion resistance. Yolgören exhibited the most severe deterioration, with a 34.84% loss in compressive strength, the lowest tensile strength, and the highest abrasion loss (0.088%), primarily attributed to poor drainage and heavy traffic. Derecik showed 22.18% strength loss and the lowest elastic modulus (14.9×103 MPa), likely due to weak subgrade and freeze-thaw cycles. Çal displayed moderate strength but had the highest capillarity coefficient and significant stiffness reduction (elastic modulus: 15.7×103 MPa), indicating high porosity and freeze-thaw damage. Çiğdemli performed best in surface durability, with the lowest abrasion loss (0.026%) and satisfactory elastic modulus. Gökçeler presented a rare case of strength gain (+0.85%) and retained acceptable stiffness, though minor surface wear (abrasion loss: 0.038%) was observed. These findings demonstrate that mix design alone does not guarantee long-term durability in rural pavements. Site-specific factors-such as curing effectiveness, drainage planning, subgrade preparation, and climate-must be considered in pavement design. A context-sensitive, performance-based approach is recommended for the sustainable development of rural road infrastructure.