Corrosion Resistant Prestressing Strand for Prestressed Concrete Bridges

Prestressing strands are the core constituents of prestressed concrete structures. Steel offers important advantages over the emerging classes of composite tendons in this application; susceptibility of prestressing steel to corrosion, however, is a concern. The market appeal of existing corrosion-resistant strands has been dampened by their high cost and some enduring technical concerns. In recent years, advanced corrosion-resistant coating and alloying strategies have been developed, which are yet to be evaluated in infrastructure applications. These new strategies provide powerful tools for overcoming the drawbacks of today’s corrosion-resistant strands. The proposed Phase I project will: (i) adapt selected corrosion protection strategies to prestressing strands; (ii) assess the pertinent damage resistance, stability and adhesion capacity of corrosion protection measures; (iii) evaluate the effects on the mechanical performance of strands, bond behavior and split cracking in concrete, and prestressing tooling; (iv) assess the corrosion resistance of the new strands; and (v) estimate the cost implications of the corrosion protection strategies adapted to prestressing strands. Similar assessments will be made of commercially available corrosion-resistant and conventional (black) prestressing strands. Promising strategies will be identified for further development towards production of corrosion-resistant strands with cost and performance attributes which favor their broad market acceptance.