Mechanism and modeling of transverse cracking development in continuously reinforced concrete pavement

The relationship between the initiation and spacing of transverse cracking in continuously reinforced concrete pavement (CRCP) and transverse steel reinforcement has been investigated. Field evaluations of CRCP test sections included surface condition inspection using digital video, ground penetrating radar (GPR) survey to determine the relative location of transverse bars with respect to transverse cracks, falling weight deflectometer (FWD) testing to evaluate the crack load transfer efficiency (LTE), and ground-truth coring. Field-testing results suggested that the mean crack spacing was identical to the design spacing of transverse steel bars. A three-dimensional finite element (FE) model was then developed to evaluate the mechanisms that contribute to the initiation of transverse cracking in CRCP. Results of the FE model indicated that two controlling mechanisms may contribute to the initiation of transverse cracking in CRCP: build-up of uniform compressive longitudinal stress at the pavement surface and tensile stress concentration in the vicinity of the transverse steel bars. In general, a close correlation appears to exist between the spacing of transverse cracking and the design spacing of transverse steel bars.