Interstate 90, Weedsport, NY
This pavement consisted of JPCP constructed on different bases, namely the standard New York configuration of a cement treated permeable base (CTPB) built on a dense graded aggregate base (DGAB) versus the alternative of a full-depth DGAB. The objective was to determine if there was an effect on the response and performance of the pavement depending on the type of base.
The environmental analysis indicates that the pavement placed on CTPB initially has smaller deflections than the pavement placed on DGAB. However, over time, the bond at the slab/base interface deteriorated such that the pavement deflections of the CTPB section surpassed those of the DGAB section. The truck testing has proven that there was a loss of support at the transverse joints in the CTPB section, which resulted in greater joint deflections under traffic loads. Thus the DGAB provided more uniform slab support, which resulted in lower strains and deflections in the pavement.
The CTPB layer increased slab surface tensile strains and joint deflections, compared to those of the DGAB section. The impact of higher slab strains and edge deflections is an increased risk of mid-slab cracking due to fatigue loading, and structural breaks at the joints due to a loss of support. Therefore, the CTPB had no positive influence on the pavement and had negative impacts on the load response. The subgrade moisture under the two sections was similar. It is recommended to utilize a DGAB base under PCC pavements instead of CPTB.