Long-Term Performance of Stone Interlayer Pavement

This paper presents an evaluation of long-term performance of an alternative flexible pavement design referred to here as stone interlayer pavement. This pavement design was introduced to reduce/defer reflective cracking experienced with soil-cement bases. The stone interlayer pavement consisted of a crushed limestone base on top of a cement-stabilized base. The performance of the stone interlayer pavement was compared to that of the conventional pavement design with a cement-stabilized base. The stone interlayer and conventional pavements were constructed on State Highway LA-97 near Jennings, Louisiana. Both pavements were monitored for 10.2 years after construction. During the evaluation period, pavement distress surveys, testing of roughness and permanent deformation, and evaluation of pavement structural capacity using dynamic nondestructive testing were conducted. Additionally, as a part of the Louisiana Transportation Research Center accelerated pavement testing research program, both pavement designs were tested to failure under the Accelerated Loading Facility in Port Allen, Louisiana. The results of this investigation showed a superior performance of the stone interlayer pavement over the conventional soil cement pavement as tested in the field as well as under accelerated loading.