PriMera Scientific Engineering (ISSN: 2834-2550)

Research Article

Volume 6 Issue 1

Moment Distribution Analysis of Frames with Tapered Members

Wisam Bukaita*

December 11, 2024

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Abstract

The traditional moment distribution method is modified to analyze statically indeterminate beams and frames that consist of prismatic and tapered members. An expression of stiffness and carry over factors for tapered members is derived based on the solution of a second order differential equation for the curvature of a rectangular cross-sectional shape tapered in depth only.

The moment distribution method is based on distributing the applied moment at any joint to the members’ ends that connected to this joint. The distributed moment can be mathematically obtained from multiplying the applied moment by a distribution factor. Meanwhile, the distributed moment is carried over to the far end of the member based on a carry-over factor of 0.5. In the modified method there are two different carry over factors; one of them is less than 0.5 and the other is larger, depending on the tapering ratio. Three different applications on the portal frame with different support conditions and different columns’ shapes are presented with numerical analysis and results.

Keywords: Distribution moment; Stiffness factor; Carry over factor; Prismatic member; Tapered member

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