Study On Predicting Transverse Cracks Distribution Of Continuously Reinforced Concrete Pavement

The use of continuously reinforced concrete pavement (CRCP) has increased over the years at home and abroad because CRCP provides a long-lasting pavement requiring little maintenance. Under temperature drop and concrete shrinkage, CRCP constrained by reinforced bar and foundation will crack inevitably. The effectiveness of CRCP is ensured by tight crack widths and adequate transverse crack spacings. When presence narrow transverse crack spacing and excessive crack opening and heavy repeated loads, CRCP may develop a punchout easily.Firstly, according to the bond-slip relation between the reinforced bar and concrete and the linear calculation model between the subgrade and concrete, the equilibrium differential equations are established for the analysis of the stress of temperature drop and shrinkage in CRCP. The analytic solution is derived and the formula is provided to calculate the CRCP stress and displacement under the temperature drop and shrinkage. The distributions of stress and displacement along the pavement longitudinal direction are analysed, and analysis crack spacing impact on the stress and displacement. Secondly, after performing a sensitivity study, concrete strength, bond-slip coefficient between concrete and base, bond-slip stiffness between concrete and steel, concrete shrinkage and expansion coefficient are key parameters. The crack distribution prediction of CRCP is accounted for their variability. Thirdly, using Monte Carlo method, considering the variability of these key parameters, study on the prediction of CRCP transverse cracking using own program. The average air temperature is changing monthly, and the temperature load is also changing monthly relative to setting temperature. And then, abalysis the field data of CRCP, the results show that the crack spacing obeys the weibull distribution, but the distribution parameters are different. Analysis the result of prediction using Monte Carlo method, the crack spacing also obeys weibull distribution. Analysis the impact of the parameters on crack spacing distribution, the results show that the variability of concrete strength greater impact on crack spacing, thermal expansion coefficient variability, concrete shrinkage variability and bond-slip stiffness between concrete and base variability little effect on crack spacing distribution, reinforcement ratio has influence on crack spacing distribution.Finally, active control of cracks is studied, the maximum crack spacing that is not to crack in the future is studied, the minimum crack spacing that is not to punchout is studied. And the example and computer program are given.