Full depth reclamation (FDR) utilizing Portland cement has been utilized successfully for over 25 years worldwide for the rehabilitation of severely failed pavements. The process involves the mixing of Portland cement into the pulverized existing road in order to achieve certain strength requirements, and offers a sustainable alternative to traditional rehabilitation processes. Historically, the process has met with mixed success, primarily due to the opinion that the more cement the better. This has led to over-cementing and subsequent shrinkage cracking of the recycled material, ultimately resulting in reflective cracking in the asphalt wearing course. Modern practices consider significantly reduced Portland cement additions that produce a less brittle material. Furthermore, pre-cracking of the cement stabilized material allows for a matrix of small micro cracks on the surface that eliminate the risk of shrinkage cracks occurring. This paper gives an overview of the FDR process together with a description of the pre-cracking process utilized in Nova Scotia. It is also demonstrated that greenhouse gas emissions are significantly reduced when FDR with Portland cement is used compared to a traditional maintenance strategy. For the covering abstract of this conference see ITRD number E217481.
Abstract