MODAL ANALYSIS OF ORTHOTROPIC COMPOSITE FLOORS SLABS WITH PROFILED STEEL DECKS

Abstract

WHEN A COMPOSITE FLOOR SYSTEM INCORPORATES A PROFILE STEEL DECK SLAB, THE SLAB ISOTROPY ASSUMPTION MAY BE QUESTIONABLE. ONE OF THE MOST COMMONLY USED SOLUTIONS TO BETTER REPRESENT THE COMPOSITE FLOOR IS TO CONSIDER AN ORTHOTROPIC SYSTEM WHERE THE MAJOR DIRECTION IS PARALLEL TO THE SLAB DECK RIBS AXIS. THE MAIN OBJECTIVE OF THIS PAPER IS TO INVESTIGATE THE ORTHOTROPIC SOLUTION FOR THE COMPOSITE SLABS. THE INVESTIGATION WAS FOCUSED ON THE COMPUTATIONAL MODELLING OF THE DYNAMICAL BEHAVIOUR OF COMMONLY USED COMPOSITE FLOORS WITH PROFILE STEEL DECKS. THE COMPOSITE FLOOR STUDIED IN THIS WORK, SPANNING 43.7M BY 14.0M, IS CURRENTLY USED FOR GYMNASTICS. THE INVESTIGATED STRUCTURAL SYSTEM DYNAMICAL RESPONSE, OBTAINED FROM FINITE ELEMENT METHOD ISOTROPIC AND ORTHOTROPIC SIMULATIONS, WAS COMPARED TO EXPERIMENTAL EVIDENCE. THE CURRENT INVESTIGATION HAS ALSO CONSIDERED THREE FUNDAMENTAL ASPECTS OF THE DYNAMICAL COMPOSITE FLOOR RESPONSE I.E.: BOUNDARY CONDITION EFFECTS, THE STEEL PROFILE DECK CONTRIBUTION AND THE COMPOSITE FLOOR NEUTRAL AXES LOCATION ON THE GLOBAL STRUCTURAL SYSTEM RESPONSE. A SUBSEQUENT PARAMETRIC ANALYSIS WAS ALSO PERFORMED TO FURTHER VERIFY THE COMPUTATIONAL MODELS ACCURACY. THESE MODELS RESULTS WERE ALSO COMPARED TO CALCULATED ANDMEASURED NATURAL FREQUENCIES OF A FULL-SCALE COMPOSITE FLOOR.