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Results from Double-Shear Tests of High-Strength Structural Bolts at Elevated Temperatures

The behavior of high-strength structural steel at elevated temperatures, especially under shear loading, is not well established in the literature. Set of data presents results from recently conducted tests on high-strength structural bolts subject to double shear loading at elevated temperatures. The parameters varied between tests included the bolt grade, bolt diameter, and temperature. Bolt grades A325 and A490 were tested. For each bolt grade, three different diameters were tested (19 mm (3/4 in), 22 mm (7/8 in), and 25.4 mm (1 in)) at five different temperatures (20 ºC, 200 ºC, 400 ºC, 500 ºC, and 600 ºC). At least three tests were conducted for each combination of parameters. The load versus displacement curves are presented herein. The results from these experiments fill a critical knowledge gap currently present in the literature regarding the behavior of high-strength structural bolts under shear loading at elevated temperatures. These data will ultimately provide a thorough understanding of the overall behavior of structural steel systems under realistic fire loading by clarifying the (i) shear behavior of high-strength structural steel bolts at elevated temperatures, and (ii) degradation in the mechanical and material properties of high-strength steel bolts with increasing temperatures.


This data set is presented in six files. One file for each diameter size (19 mm (3/4 in), 22 mm (7/8 in) and 25.4 mm (1 in)) for both bolt types (A325 and A490). Within the files, there are separate tables representing the load-displacement curves for each test. Each test was assigned a unique name. The nomenclature includes the bolt diameter, type, test temperature, and specimen number. For example, test “19A325T20-1”. The first two digits represent the bolt diameter (19 mm (3/4 in), 22 mm (7/8 in), or 25.4 mm (1 in)), the next four characters represent the bolt type (A325 or A490), followed by the letter T and the temperature at which that bolt was tested (T20= 20 ºC (Ambient Temperature); T200= 200 ºC; T400= 400 ºC; T500= 500 ºC; T600= 600 ºC), and lastly, the number of the specimen.

Related Publications:

  • Seif, M., Peixoto, R., Weigand, J., Main, J., and Vieira, L. (2017) “High-Strength Bolts at Elevated Temperatures Under Double-Shear Loading: Testing, Modeling, and Application”. NIST Technical Note TN-xxxx, National Institute of Standards and Technology, Gaithersburg, MD.
  • Peixoto, R., Seif, M., and Vieira, L. (2017) “Double-shear tests of high-strength structural bolts at elevated temperatures.” Journal of Fire Safety.
  • Weigand, J. M., Peixoto, R., Vieira, L., and Seif, M. (2017) “An Empirical Component-Based Model for Shear Behavior in High-Strength Bolts at Elevated Temperatures.” Journal of Constructional Steel Research.
  • Seif, M., Weigand, J., Peixoto, R., and Vieira, L. (2017) “Behaviour of high-strength bolts at elevated temperatures under double-shear loading.” Eurosteel 2017 Conference Proceedings, Copenhagen, Denmark
Created August 8, 2017, Updated November 15, 2019