Determination of the secondary bending stress in cold-formed steel connection


  • Apai Benchaphong Department of Civil Engineering, Faculty of Engineering, Rajamangala University of Technology Krungthep, Bangkok 10120, Thailand
  • Rattanasak Hongthong Department of Civil Engineering, Faculty of Engineering, Rajamangala University of Technology Krungthep, Bangkok 10120, Thailand
  • Sutera Benchanukrom Faculty of Agricultural Technology and Industrial Technology, Phetchabun Rajabhat University Petchabun, Petchabun 76000, Thailand
  • Nirut Konkong Irrigation Office 3 - Royal Irrigation Department, Phitsanulok 65000, Thailand


analytical method, bolt connection, cold-formed steel, load transfers, secondary bending stress


The purpose of this analysis was to study the effect of bolt load transfers and geometric variables which influence the secondary bending stress factor of cold-formed steel bolt connections using the analytical method.  The Neutral Line Concept (NLC) was a method for determining the effect of secondary bending in bolt connection, but some important factors were ignored, such as load transmission occurring at the middle row bolts, overlap stiffening due to the action of manufactured and bolt stiffness.  There was an effect on the level of the secondary bending stress in the bolt-row.  To obtain accurately the secondary bending stress factor, the Modified Neutral Line Concept (MNLC) was proposed.  MNLC was modified from NLC by added ignoring factors to the process of calculating.  The accuracy of MNLC was validated by finite element analysis.  The results showed that the analytical method had a good correlation with the finite element analysis.  The most critical points for secondary bending stress in a lap shear connection were in the outer bolt rows of the connection.


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How to Cite

Apai Benchaphong, Rattanasak Hongthong, Sutera Benchanukrom, & Nirut Konkong. (2023). Determination of the secondary bending stress in cold-formed steel connection. Journal of Current Science and Technology, 11(2), 287–298. Retrieved from



Research Article