Evaluation on Sectional Warping Constants of Equal Leg Angle with Lips

Abstract:

An equal leg angle with lips subjected to torsional moment will result in pure torsional shear, warping shear, and warping normal stresses. Evaluation of these torsion induced stresses is not a routine job for practicing engineers as one of major difficulties arises from the determination of sectional warping constant (C_w). Calculation of the warping constant (C_w) for the equal leg angle with lip steel section is a tedious and difficult task and thus presenting an obstacle to routine design. Although C_w formulas and values for selective cold-formed steel sections are available in the AISI manual, most practicing engineers have no idea how to evaluate C_w constants for sections that are not listed in the AISI manual. This paper provides a detailed step-by-step numerical procedure for evaluating the C_w value of the equal leg angle with lips steel open section. Comparison between the calculated values and those listed in the AISI manual shows virtually no differences, thus proving the reliability of our proposed procedure. Ultimately, we present an useful tool in computing the C_w for a equal leg angle with lips, without the use of sophisticated computer software.

• Periodical: Applied Mechanics and Materials (Volume 145)
• Pages: 320-324
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.145.320
• Online since: December 2011
• Authors: Jui Ling Liu, Dung M. Lue, Wei T. Hsu
• Keywords: AISI, Cold-Formed Steel, C_w, Equal Leg Angle with Lip Steel Section, Warping Constant

References

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[7] AISI, Cold-Formed Steel Design Manual (Washington, American Iron and Steel Institute 2002). element 1－ ( point 1 to point 2 ) element 2－ ( point 2 to point 3 ) element 3－ ( point 3 to point 4 ) element 4－ ( point 4 to point 5 ) Sectional dimensions D = 8. 000 in., B = 2. 500 in. A = 1. 46 in. 2, in, t = 0. 105 in., in. in., in. Fig. 1. Section 4LS4 ×105 as used in the illustrative example S: shear center C : centroid r : distance between tangent line and centroid ro : distance between tangent line and shear center Fig. 2. Coordinates and tangential distances in an open cross section Fig. 3. Coordinates and tangential distances in an open thin-walled section Fig. 4. Distribution of w on a plate element.

DOI: 10.1007/978-3-7091-0324-1_2