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In many areas of the United States, corrosion is a common cause of steel bridge deterioration. This has caused some state agencies to use stainless steel for bridges in very corrosive environments. However, most steel bridges in the United States contain numerous slip-critical bolted connections, and stainless steel bolts have not historically been used in slip-critical connections. Therefore, there is limited or no guidance on the specified pretension to which stainless steel bolts can be installed. There is also limited or no guidance on the installation parameters, such as the nut rotation for the turn-of-nut method or initial torque and nut rotation for the combined method of installation. In this project, torqued tension tests were conducted on 128 ASTM A1082 UNS S32205 (2205) and 128 ASTM A1082 UNS S17400 Type 630 Condition H1150 (17–4-H1150) stainless steel fastener assemblies. All bolts tests were 7/8 in. in diameter and ranged from 2 to 5.5 in. in length. Multiple types of lubricants were used in the testing to evaluate their effectiveness. Test results were used to improve upon an existing method to determine the specified pretension and installation parameters of each fastener assembly type, depending on strength, ductility, and lubricant criteria. Analysis determined that 2205 fastener assemblies can be installed to a specified pretension of 80% of their ultimate strength while 17–4-H1150 fastener assemblies can be installed at their yield strength. Nut rotation values from snug for the turn-of-nut installation method and initial torque range and nut rotation values for the combined installation method are also provided in the paper. • Torqued tension testing of 2205 and 17–4 PH Condition H1150 stainless steel fastener assemblies. • Specified pretension values for 2205 and 17–4 PH Condition H1150 stainless fastener assemblies. • Turn-of-nut installation for 2205 and 17–4 PH Condition H1150 stainless fastener assemblies. • Combined installation method for 2205 and 17–4 PH Condition H1150 stainless fastener assemblies. [ABSTRACT FROM AUTHOR]

ASTM A1010 (A709 Gr50CR) is a dual-phase stainless steel that is gaining popularity in the US bridge market due to its corrosion resistance and potential for life cycle cost savings. Several recent research studies and pilot bridge construction projects have been initiated across several different states and agencies. Recent research has primarily focused on corrosion resistance and galvanic corrosion when in contact with dissimilar metals commonly used in the steel bridge industry. Ongoing research is investigating the structural behavior of connections such as pretensioned bolted joints and welds. Six bridges have been constructed in the US using A1010 material in five different states. Several other agencies are considering or have initiated discussions on the use of this new material to reduce maintenance costs, particularly in highly corrosive environments where other common bridge materials and coating systems require costly corrosion-protection maintenance. [ABSTRACT FROM AUTHOR]