This research presents the results of an experimental investigation to identify the significant factors influencing concrete/rebar bond failures resulting in cracking of continuously reinforced concrete pavements (CRCP). Water to cement ratio, rebar temperature at the time of concrete pouring, and rebar surface condition (as-received vs. corroded) were factors investigated in this research. Water to cement ratio (w/c), rebar temperature, and presence of corrosion products on rebar surface have a significant influence on the rebar-concrete bond strength. The 28-day shear strength measurements showed an increase in rebar-concrete bond strength as the water-to-cement ratio (w/c) was reduced from 0.50 to 0.40. There was a reduction in the peak pullout load as the rebar temperatures increased from 14oF to 252oF for the corroded and non-corroded rebar experiments. The corroded rebar pullout test results showed a 20-50% reduction in bond strength compared to the non-corroded rebars.
Abstract