Analysis of laterally loaded flat-plate structures

Abstract

Flat-plate reinforced concrete structures tend to behave nonlinearly, even at service load levels, when subjected to lateral loading. This is due mainly to the deformations that occur at the column-to-plate boundaries. Currently available structural analysis computer programs assume linearly elastic behaviour and thus underestimate lateral displacements. This paper describes an efficient, easy-to-use structural analysis procedure and computer program for predicting the nonlinear response of flat-plate structures subjected to lateral loading. The structure is assumed to be a three-dimensional frame comprised of linearly elastic columns, flat-plate floor panels and shear walls, and nonlinear "connections" between the columns and the flat-plate floors. Utilizing all available experimental data, standardized functions have been derived to predict the nonlinear moment–rotation behaviour of these plate-to-column connections. The functions have been incorporated into the structural analysis computer program. Examples are presented to illustrate the capabilities of the program, to compare results computed by it with published results, and to illustrate the effects of several geometric and material parameters on the behaviour of the structure. Key words: reinforced concrete, flat plate, structural analysis, nonlinear analysis, lateral load analysis.