Flat Plates with Regular and Irregular Column Layouts. I: Analysis

By the use of the structural membrane theory, an effective and accurate method for determining bending moments in flat plates is developed. This involves using a three‐dimensional model, which removes the inherent limitations of the two‐dimensional frame representation of plates as recommended in the ACI 318 code. For square and rectangular layouts, this method yields excellent agreement with existing test data. The method makes it possible to analyze plates with triangular, hexagonal, and other regular column arrangements. It furthermore furnishes an approximate design for plates with irregular column layouts. Originally developed for the design of thin shells supported on irregularly spaced columns, the structural membrane theory provides accurate results for similarly supported flat plates. With extreme simplicity in both input and output files, combined with limited requirements for computer memory and computer time, it promises to become a popular tool for the practicing engineer.