Articles
DOI DOI: 10.62441/actainnovations.v63i.1160

K-FACTORS FOR COLUMN IN BRACED AND UNBRACED FLAT PLATE SYSTEM

Ahmed Y. A. Zainul-abideen1, Furat Y. Al-Ghalibi 2, Samer S. Shukur3
  1. 1 Department of Civil Engineering, Faculty of Engineering, University of Kufa, Najaf, Iraq.
  2. 2 Department of Structures and Water Resources Engineering, Faculty of Engineering, University of Kufa, Najaf, Iraq.
  3. 3 Department of Civil Engineering, Faculty of Engineering, University of Kufa, Najaf, Iraq.

Abstract

Two approaches between (K-factor approximate approach), and (Column stiffness modification approach) are presented for calculating the effective length factor (K-factor) of columns in braced and unbraced flat plate system. This study integrates K-factor, which is calculated from theoretical values based on records obtained from measurements between the stiffness coefficients derived by Notes of ACI-318-12 code [1] contained within the equivalent frame method (EFM). A subassembly is used to add second-order analysis (P-Δ) effects, and column stability functions are used to explain differences in computational accuracy between two methods for incorporating stiffness at the column-slab joints. The second method proceeds through alignment and is developed using high-accuracy approximate equations to the current US National codes provisions with a refined calculation method performed through that. The calculations consist of solving a number of problems and comparing the results obtained using both proposed methods—based on Newton-Raphson iterations—to those obtained with the approximate equations. Comparisons are made with the proposed method, practical alignment chart methods and so on for different world specifications. The predicted results show the reliability of the proposed equations as well as simplicity of enhanced alignment chart method that can be easily incorporated to practical engineering use.

How to Cite

Zainul-abideen, A. Y. A., Al-Ghalibi , F. Y., & Shukur, S. S. (2026). K-FACTORS FOR COLUMN IN BRACED AND UNBRACED FLAT PLATE SYSTEM. ACTA INNOVATIONS, 63, 931–943. https://doi.org/10.62441/actainnovations.v63i.1160
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