Evaluation of load transfer characteristics in roller-compacted concrete pavement

Load transfer significantly affects the performance of a concrete pavement. Poor load transfer may result in faulting, transverse cracking, and pumping, as well as reducing the service life of the pavement. Because roller-compacted concrete pavement (RCCP) is constructed without dowel bars, load transfer at its joints or cracks mainly depends on shear transfer capabilities induced by aggregate interlocks and base stiffness. In this paper, we evaluate the deflection-based load transfer efficiency (LTEδ) across transverse cracks and its influencing variabilities of a full-scale RCCP test section in South Korea, using a falling weight deflectometer (FWD). Two different aggregate gradations with 19- and 13-mm maximum aggregate size were used in RCCP mixtures to capture their effects on LTEδ. FWD tests were conducted at different times over a year to consider the effects of temperature changes and crack opening size on LTEδ. Results showed that temperature changes, crack opening size, and aggregate size significantly affect the LTEδ. Significant reduction of LTEδ was observed for the RCCP mixture with 13-mm maximum aggregate size. Therefore, using a 19-mm maximum aggregate size in RCCP mixture provides a better LTEδ and is expected to improve the structural performance of RCCP.