Detrimental effects of tie bars on post-tensioned concrete pavement performance

The detrimental effects of tie bars that existed at the armored expansion joint in the gap slab and at the longitudinal joint between the PTCP slabs on the PTCP performance were investigated numerically in this study. Finite element models of the PTCP system including tie and dowel bars at the armored joint in the gap slab and tie bars at the longitudinal joint between the slabs were created. The stresses of the gap slab under the transverse tensioning and those of the PTCP slabs due to the longitudinal tensioning and drying shrinkage were analyzed to find how the tie bars affected the stress distribution. The analysis results showed that the existence of tie and dowel bars at the armored joint partly resisted employing prestress in the gap slab under the transverse tensioning, and the tie bars at the longitudinal joint not only partly resisted employing prestress but also induced large tensile stresses at their locations when subjected to the longitudinal tensioning and drying shrinkage. Some approaches to mitigate a loss of prestress caused by tie bars were examined and recommendations were finally made to improve the PTCP performance when tie bars were used in the PTCP system.