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Classification of compression members for local buckling

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Compression sections are classified into non-slender and slender elements. A section is considered non-slender if the width-thickness ratio is larger than the value shown in the AISC B4.1a table, and it is shown in the table below. When the width-thickness ratio is less than the section will be defined as a slender element. Almost all the HP and W sections listed in the AISC manual for yield strength of 50 ksi are non-slender. The design value listed by AISC reflects the reduced design stresses available for the slender sections.

If the member is defined as a non-slender element compression member, then, the nominal compressive strength is determined from AISC E3 on the limit state of flexural buckling. But if the member is defined as a slender element member, the nominal compressive strength will be determined from E7 of the AISC and it will be the lowest of the flexural buckling, torsional buckling, and flexural-torsional buckling.




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My name is Mohammad Hamdan, and I am a Civil/bridge Engineer with extensive professional background and experience in the field of construction. I have 10+ years of experience in the construction field. During my professional career, my emphasis has been placed on structural projects, mainly bridges, infrastructure and roads. Reading and practicing the design of structures is my passion.i was lucky to be a part of a big team that executed major highway interchanges. I believe in spreading the knowledge, thus, i compose these courses to share my experience and knowledge. My course focuses on the practical side of construction field. On other word, i am sharing some of what new engineers need to know about construction field. Beside working on construction field, i love writing some articles on my website ( curious civil engineer) Moreover, i wrote some engineering papers, you can check them  by searching my name on Google (Mohammad mamon Hamdan)