Analysis of Continuously Reinforced Concrete Pavement Behavior Using Information in the Rigid Pavement Database

摘要

Microscopic behavior and distress types in continuously reinforced concrete pavement (CRCP) were investigated using the information in the TxDOTs rigid pavement database. Crack width behavior was evaluated using the information from two test sections. Transverse crack width decreased over time, which is quite contrary to whats been accepted as a general crack width behavior in CRCP. The reason for this decrease is not known. Concrete temperature has a dominant effect on the crack width behavior. Most of the times, CRCP slabs exhibit flexural behavior at transverse cracks due to temperature variations through the depth. The neutral axis for crack width variations appears to exist below the mid-depth. Two major distress types were observed in the field: horizontal cracking induced distress and edge punchouts. Even though the mechanisms for the two distress types are different, the appearance of the two distresses could be quite similar. The mechanism of horizontal cracking appears to be curling of concrete slab, caused by large temperature variations in the upper portion of concrete slab. Large coefficient of thermal expansion and modulus of elasticity of concrete, and temperature variations appear to be causing this distress. Transverse crack spacing or concrete temperature does not appear to have substantial effects on load transfer efficiency (LTE) in CRCP. The insensitivity of LTE to temperature is different from the behavior of Jointed Concrete Pavement (JCP). In JCP, LTE at a transverse joint is quite sensitive to concrete temperatures. Crack widths get larger with lower temperatures, which should result in lower LTEs. However, field evaluations indicate almost constant LTEs evaluated in the summer and in the winter. Also, transverse crack spacing does not appear to have substantial effects on slab deflections. Based on the findings, it appears that load transfer efficiency, as in the current form, is not a good indicator for structural condition of CRCP. Efforts should be made to clarify the effects of transverse crack spacing on CRCP performance.