This paper focuses on a section of the state road D28, Bjelovar northern bypass, Republic of Croatia, which was opened to traffic in 2002. Following the expiration of the 20-year design service life, it was determined that the section required reconstruction, as visual inspections indicated a significant deterioration in ride comfort. To define the appropriate reconstruction strategy, specifically the strengthening of the pavement structure, reliable data on pavement bearing capacity were needed. Historical design thicknesses were compared with current measurements, and deflection data obtained using a Falling Weight Deflectometer (FWD) were analyzed for sections where visual assessments suggested reduced structural capacity. Based on the calculated modulus of elasticity, a pavement structure was designed and subsequently strengthened through the addition of an extra load-bearing layer composed of a cold-recycled mixture with foamed bitumen.
Vukelić et al. (2026) studied this question.