ABSTRACT
Chemical stabilization of reclaimed and marginal materials with cement has proven to be a viable option for sustainable design and construction of flexible pavements. The primary role of the treated base layers is to provide a robust platform that withstands complex stress paths imparted by moving traffic loads. In addition to considerations of load-related distresses in the structural design process of pavements with cement treated layers, the selection of appropriate cement content in the laboratory mixture design greatly influences the service life of pavements. For instance, excessive cement content in base mixes can potentially result in shrinkage cracking that will further propagate to the surface layers. The primary focus of this study was to develop and calibrate a new generation of fatigue performance model with considerations of the traffic-induced stresses, as well as the shrinkage parameters in the laboratory mixture design of cement treated layers. To achieve this objective, a comprehensive laboratory experiment design was developed to characterize the tensile and shrinkage behavior of cement stabilized virgin and reclaimed materials. Subsequently, a logical performance model was proposed and further calibrated using 51 pavement sections. Ultimately, the performance of the developed model was tested on a new set of data for cross-validation purposes. The proposed calibrated fatigue performance model with the inclusion of IDT and shrinkage cracking characteristics of the cement treated materials provides a practical approach for the design of pavements with cement stabilized foundations.
