Results of Evaluation of Bolt Failures at the R.C. Byrd Locks and Dam

During rehabilitation of the roller gates at the R.C. Byrd Locks and Dam, Gallipolis, OH, the U.S. Army Engineer District, Huntington found some of the bolts had failed. Analysis by the Construction Engineering Research Laboratory found the primary cause of failure to be temper embrittlement. The microstructure of the bolt revealed a brittle fracture, with the fracture mode being intergranular. The presence of chlorides also accelerated the galvanic corrosion that occurred between the bolt and nut. The temper embrittled bolts have approximately 10 times higher corrosion rate immersed in Ohio River water than the non-temper embrittled bolts. The non-temper embrittled bolts should have a 40 to 50 year service life expectancy, assuming the Ohio River water chemistry does not change significantly. The suggested material replacement is a martensitic age-hardenable stainless steel combining the very good corrosion resistance characteristics of Type 304 stainless steel and the moderate strength characteristics of Type 410 stainless steel. Either ARMCO 17-4 PH stainless steel or Carpenter Custom 450 stainless steel is recommended for us in aqueous environments where high strength and corrosion resistance is required.
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