EVALUATION OF THE URETEK METHOD FOR PAVEMENT UNDERSEALING AND FAULTING CORRECTION. INTERIM REPORT

This study was conducted to monitor the effectiveness of work to rehabilitate faulted concrete pavement by pressure injecting a polyurethane chemical to raise and stabilize slabs and fill voids under slabs. This process is known as the Uretek method. The primary objective of this research was to evaluate the effectiveness of the Uretek method in lifting and stabilizing faulted slabs in jointed concrete pavement. A secondary objective was to evaluate the effectiveness of the Uretek method in filling voids to improve load transfer on a pavement where faulting is not yet a problem. The sites selected for this work were on Interstate 55 in Tate and Panola Counties and on US 78 in Marshall County. All sites were on four-lane divided highways and consisted of jointed concrete pavement over a cement treated base. Deflection, faulting, roughness, profile survey, and visual distress surveys were conducted for all of the areas treated on I-55. The same performance tests were conducted on US 78 except for faulting and roughness. The results from this project have shown that the Uretek method reduces the maximum deflections, increases the joint load transfer efficiency, and moderately reduces faulting. This procedure did cause a void under the mid-slabs; however, going back and injecting at mid-slab reduced the deflections by approximately 50%. The Uretek process appeared to work better in cooler weather and early morning hours. It is recommended that the Uretek method be used again to reduce faulting on jointed concrete pavement.