Full-depth concrete pavement repair with steel reinforcements

Abstract

Some of the conventional Full-Depth Repairs (FDR) in Jointed Concrete Pavement (JCP) suffered recurring failures in less than one year. Under very heavy truck trafficking, tie bars were ruptured, and the slabs were settled for as much as 100mm. This indicates the conventional method of slab replacement does not address the underlying problem. Falling Weight Deflectometer (FWD) and Dynamic Cone Penetrometer (DCP) were utilized to determine Load Transfer Efficiency (LTE) and base/subgrade support conditions, respectively. After one month of the heavy truck trafficking since opening to traffic, some transverse joints had LTE less than 10%. DCP results confirmed extremely weak base/subgrade support. It was concluded that the weak base/subgrade support was one of the main culprits for the recurring failures. For more effective repair of failures in JCP with heavy truck traffic, an innovative FDR technique with two layers of steel reinforcements and tie/dowel bars to adjacent JCPs was developed. The weak and poor base/subgrade layers were completely removed and replaced with concrete and steel reinforcements. Both longitudinal and transverse repair joints were designed considering the compatibility of concrete volume changes between the existing JCP slabs and repair slabs. Condition survey results indicated that the performance to date has been excellent with no visible distress under almost two years of the heavy truck traffic. For the repair of JCP sections with recurring failures, the implementation of the proposed technique with steel reinforcements and joint designs is expected to result in improved performance.