DYNAMIC RESPONSE TO MOVING MASSES OF RECTANGULAR PLATES WITH GENERAL BOUNDARY CONDITIONS AND RESTING ON VARIABLE WINKLER FOUNDATION

Abstract

THE DYNAMIC RESPONSE TO MOVING MASSES OF RECTANGULAR PLATES WITH GENERAL CLASSICAL BOUNDARY CONDITIONS AND RESTING ON VARIABLE WINKLER ELASTIC FOUNDATION IS INVESTIGATED IN THIS WORK. THE GOVERNING FOURTH ORDER PARTIAL DIFFERENTIAL EQUATION IS SOLVED USING A TECHNIQUE BASED ON SEPARATION OF VARIABLES, THE MODIFIED METHOD OF STRUBLE AND THE INTEGRAL TRANSFORMATIONS. NUMERICAL RESULTS IN PLOTTED CURVES ARE THEN PRESENTED.  THE RESULTS SHOW THAT AS THE VALUE OF THE ROTATORY INERTIA CORRECTION FACTOR R_O INCREASES, THE RESPONSE AMPLITUDES OF THE PLATE DECREASE AND THAT, FOR FIXED VALUE OF R_O, THE DISPLACEMENTS OF THE PLATE DECREASE AS THE FOUNDATION MODULUS F_O INCREASES FOR THE VARIANTS OF THE CLASSICAL BOUNDARY CONDITIONS CONSIDERED. THE RESULTS ALSO SHOW THAT FOR FIXED R_O AND F_O, THE TRANSVERSE DEFLECTIONS OF THE RECTANGULAR PLATES UNDER THE ACTIONS OF MOVING MASSES ARE HIGHER THAN THOSE WHEN ONLY THE FORCE EFFECTS OF THE MOVING LOAD ARE CONSIDERED. FOR THE RECTANGULAR PLATE, FOR THE SAME NATURAL FREQUENCY, THE CRITICAL SPEED FOR MOVING MASS PROBLEM IS SMALLER THAN THAT OF THE MOVING FORCE PROBLEM FOR ALL VARIANTS OF CLASSICAL BOUNDARY CONDITIONS, THAT IS, RESONANCE IS REACHED EARLIER IN MOVING MASS PROBLEM THAN IN MOVING FORCE PROBLEM. WHEN F_O AND R_O INCREASE, THE CRITICAL SPEED INCREASES, HENCE, RISK IS REDUCED.