Investigation of Deterioration of Stainless Steel Dowel Tubes Under Repeated Loading
Principal Investigator:
Lev Khazanovich, Associate Professor, Civil Engineering
Co-Investigator:
- Arturo Schultz, Professor, Civil Engineering
Project Summary:
The Minnesota Department of Transportation (Mn/DOT) has selected a new dowel bar to be used as a bid alternative for its high performance Portland Cement Concrete (PCC) pavements. This dowel bar is a 316L stainless steel schedule 40 pipe, with a finished (polished) surface, conforming to ASTM A312. In this study, long-term performance of the new dowel bar will be investigated by subjecting a doweled joint to accelerated repeated loads through the use of the Minnesota Accelerated Loading Facility (Minne-ALF). Assessment of long-term dowel effectiveness will be made based on the testing results. Although this dowel bar should provide sufficient shear transfer capacity and low concrete bearing stresses, there is a concern that lack of a solid core may not provide sufficient resistance of the cross-section to distortion under a heavy axle loading. Those distortions may cause horizontal cracking in PCC slabs resulting in loss of dowel effectiveness (load transfer) and causing joint spalling. The dowel bar has a minimal nominal size of 32 mm (1.25 inches), a length of 381 mm (15 inches), and a wall thickness of 3.5 mm (0.14 inches). The Mn/DOT special provisions indicate that this dowel bar shall be filled with a durable material or have snug-fitting end caps to prohibit any intrusion of concrete or other materials. For the purpose of this study, the snug-fitting end caps shall be used, thereby, providing a more critical design in lieu of the filled pipe option.
Sponsors:
Project Details:
- Start date: 08/2004
- Project Status: Completed
- Research Area: Infrastructure
- Topics: Bridges and Structures