Evaluating the Cracking Resistance of the Semiflexible Pavement Mixture Using the Semicircular Bending Test.

Semiflexible pavement (SFP) is attracting increasing interest due to its exceptional load-carrying capacity. However, there is limited understanding of its cracking performance and mechanisms. This study investigated the suitability of the emerging cracking resistance parameters, the flexible index (FI) and cracking resistance index (CRI), derived from the semicircular bending (SCB) test, in elucidating the mid-temperature resistance of SFP mixtures against cracking. The influence of styrene-butadiene-styrene-modified asphalts and styrene-acrylic emulsion/styrene-butadiene rubber-modified cement mortars on the anticrack property of SFP mixtures was also determined. Results indicated a high correlation (R2=0.95) between the FI and CRI of various SFP mixtures, with CRI exhibiting more promise than FI in assessing the fracture resistance of SFP mixtures due to its higher discrimination potential and lower variability. Enhancing the bending strength of cement mortar or increasing the CRI/Nf value of asphalt binder were identified as effective means to improve the anticracking ability of SFP. Therefore, improving the binder toughness of both cement mortar and asphalt is essential for enhancing the performance of SFP against cracking. [ABSTRACT FROM AUTHOR]