Edinburgh Napier University

  The current design practice of plate-and-grid structures in buildings, such as waffle slabs and ribbed plates, is relied largely on code-specified approximate methods, and the deflection of the system is rarely evaluated owing to the complexity of calculations. In this paper, an analogous stiffened plate is presented to model the plate-and-grid structures. A semi-analytical method is proposed based on the finite element method to obtain an accurate analysis of the stiffened plates. The proposed method of analysis has more flexible geometry adaptability and higher efficiency in reducing the unknown variables as compared to the general finite element methods, as well as less computation time and cost. The predictions of the proposed analyses for example structures agree very well with those of the finite element method and experiment. KEY WORDS Plate-and-beam structures, stiffened plates, finite element method.