Effect of Base Type on the Transverse Cracking of Jointed Plain Concrete Pavements-A Study of LTPP SPS-2 Sections

Abstract

A previous sensitivity study indicated a tendency of Pavement ME to predict more transverse cracking for Jointed Plain Concrete Pavements (JPCP) with aggregate bases than those with stabilized bases. Such a tendency contradicts the experience of some engineers who have successfully used aggregate bases to achieve robust and enduring JPCPs. The controversy triggered an in-depth investigation of the JPCP models by comparing them to an independent 3-D finite element model, which showed that Pavement ME under predicted the environmental stress for JPCPs with stabilized bases and also neglected the benefit of aggregate bases in accommodating the deformation of the surface layer and thus reducing its stress. However, this investigation was solely based on numerical modeling and not validated by any field evidences. This study further examines the issue based on an analysis of SPS-2 JPCP field experiments of the long-term pavement performance (LTPP) database. While the SPS-2 sections were designed to investigate the effect of various factors such as base type, thickness, climate, and so forth on the structural performance of the JPCP, this study is focused on the comparison of different base types, namely dense graded aggregate base (DGAB), permeable asphalt treated base (PATB) and lean concrete base (LCB). The interplay between base type and the other factors is also discussed.