Performance of Post-Tensioned Curved-Strand Connections in Transverse Joints of Precast Bridge Decks

• Main Author: Wells, Zane B.
• Format: Others
• Published: DigitalCommons@USU 2012
• Subjects: Performance; Post-Tensioned; Curved-Strand Connections; Transverse Joints; Precast Bridge Decks; Civil and Environmental Engineering; Engineering
• Online Access: https://digitalcommons.usu.edu/etd/1222; https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=2236&context=etd

Accelerated Bridge Construction (ABC) techniques have resulted in innovative options that save time and money during the construction of bridges. One such group of techniques that has generated considerable interest is the usage of individual precast concrete members. Utilizing precast concrete decks allows for offsite curing, thus eliminating long delays due to formwork and concrete curing time. These precast concrete decks have inherent joints between the individual panels. These joints are locations for potential leakage, which can lead to corrosion or inadequate long-term performance. Post-tensioning the precast deck panels helps to eliminate leakage; however, conventional longitudinal post-tensioning systems require complete deck replacement in the event of a single faulty deck panel. A proposed post-tensioned, curved-strand connection allows for a single panel to be replaced. The capacity of the proposed curved-strand connection was investigated in order to compare its behavior to other systems that are currently in use. Tests were performed in composite negative bending, beam shear, and positive bending. The curved strand connection was found to behave similarly to the standard post-tensioning system in positive bending and shear. The curved-strand connection was found to be comparable to a standard post-tensioning system. The ultimate capacity of the curved-strand connection in negative bending was found to be 97% of the standard post-tensioning. Pre-stress losses were measured and predicted for the service life of the connection and were found to be 6% at the 75- year service life of a bridge.