MOVING LOAD ON A VISCOELASTIC LAYERED SYSTEM

A SOLUTION TECHNIQUE IS DEVELOPED AND PRESENTED FOR THE INVESTIGATION OF THE STRESSES AND DISPLACEMENTS INDUCED IN A THREE LAYER VISCOELASTIC SYSTEM THAT IS SUBJECTED TO UNIFORMLY DISTRIBUTED NORMAL LOADS. IN THIS INVESTIGATION, TWO DIFFERENT CASES ARE CONSIDERED: (1) A STEADY LOCALIZED LOAD IS MADE TO MOVE AT A CONSTANT VELOCITY IN A STRAIGHT LINE ON THE INITIALLY FLAT SURFACE OF A THREE LAYER SYSTEM. THE MATERIAL IN EACH LAYER IS LINEARLY VISCOELASTIC, ISOTROPIC, AND HOMOGENEOUS, WITH STRESS-STRAIN RELATIONS EXPRESSED IN HEREDITARY INTEGRAL FORM. THE SYSTEM HAS NO BODY FORCE, IT IS AT CONSTANT TEMPERATURE, INITIALLY AT REST AND UNDISTURBED. INERTIA EFFECTS ARE NEGLECTED TO GIVE A QUASI-STATIC BOUNDARY VALUE PROBLEM. THE PROBLEMS CONSIDERED ARE THEREFORE WITHIN THE REALM OF THE USUAL ASSUMPTIONS MADE IN A LINEAR THEORY, I.E., INFINITESIMAL STRAINS AND BOUNDARY CONDITIONS ARE APPLIED TO THE ORIGINAL UNDEFORMED SURFACE. (2) THE REST OF THE INVESTIGATION IS CONCERNED WITH THE RESPONSE OF THE SYSTEM TO A LOAD THAT IS REPEATEDLY APPLIED TO THE SAME REGION ON THE SURFACE AT A SPECIFIED FREQUENCY. THE RESPONSE VARIABLE THAT IS TREATED IN DETAIL IN THIS REPORT IS THE NORMAL DEFLECTION. THIS DOES NOT IN ANY WAY DETRACT FROM THE GENERALITY OF APPLICATION OF THE METHOD TO BE PRESENTED, SINCE THE SAME GENERAL APPROACH MAY BE FOLLOWED IN THE CASE OF OTHER RESPONSE VARIABLES LIKE STRESS AND RADIAL DEFLECTION. THE NORMAL DEFLECTION OBTAINED WHEN THE LOAD IS STATIONARY AND THE SYSTEM IS ASSUMED TO BE ELASTIC IS PRESENTED. THE CORRESPONDENCE PRINCIPLE IN THE FORM OF FUNCTIONAL INTEGRAL EQUATIONS IS THEN APPLIED TO THIS SOLUTION, AND THE VISCOELASTIC RESPONSE IS OBTAINED. THE LOAD IS MADE TO MOVE AND THE SOLUTION FOR THE NORMAL DEFLECTION IN THIS CASE IS FORMULATED. THE LOAD IS THEN REPEATEDLY APPLIED AT A SPECIFIED FREQUENCY AND THE SOLUTION FOR THIS CASE IS ALSO FORMULATED. A COMPUTER PROGRAM IS WRITTEN TO NUMERICALLY OBTAIN THE RESULTS FOR THE LATTER CASE. THE MAGNITUDE OF THE ACCUMULATED DEFLECTIONS OBTAINED FOR A VARIETY OF SPECIFIED FREQUENCIES ARE PRESENTED IN THE REPORT. /AUTHOR/

  • Supplemental Notes:
    • R68-37, 180 PP, 12 FIG, 3 TAB, 77 REG, 4 APP
  • Corporate Authors:

    Massachusetts Institute of Technology

    Department of Civil Engineering, 77 Massachusetts Avenue
    Cambridge, MA  United States  02139
  • Authors:
    • Moavenzadeh, F
    • ELLIOTT, J F
  • Publication Date: 1968-6

Subject/Index Terms

Filing Info

  • Accession Number: 00205744
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 24 1994 12:00AM