The Two Isotropic Asymptotes of Fiber Composites, [report]

Ernest Y. Robinson
1988 unpublished
F04701-85-C-0086-P00019 8c. ADDRESS (City, State, and ZIP Code) 10 SOURCE OF FUNDING NUMBERS PROGRAM PROJECT TASK WORK UNIT ELEMENT NO NO NO ACCESSION NO . q* -I 11 TITLE (Include Security Classification) The Two Isotropic Asymptotes of Fiber Composites % PERSONAL AUTHOR(S) Robinson, Ernest Y. 13a TYPE OF REPORT 13b TIME COVERED 14 DATE OF REPORT (Year, Month, Day) 1S PAGE COUNT % FROM TO ;%Opp 16 SUPPLEMENTARY NOTATION 17 COSATI CODES J 1 SUB ECT TERMS (Cgntinue on, revere if neceslary
more » ... frby hlock nubet FI ELD GROUP SUB-GROUP .omp.iance ISOtropic Ll.MlL~s suropicr~ 7roper lie, D R Composites , Quasi-isotropic Asymptotes BTCFiber Composites Quasisotropic Limits ABSTRACT (Continue on reverse if necessary and identify by block number) In conventional laminate analysis of fiber reinforced materials, the in-plane directional , stiffness of constituent plies is summed to determine the entire laminate's S characteristics. Conventional laminate analysis indicates that in-plane elastic isotropy .. % . accompanies certain ply pattern combinations.,--stfh as 0 ± 60 and 0/9Q/±45? and in general all laminates with three or more plies and orientation uniformly distributed from 0 to 180 deg. A corresponding analog for this quasi-Jisotropic stiffness also exists for in-plane compliance . in which compliance values are serial, and overall in-plane material property is determined by compliance summation. The two isotropic asymptotes are analogous to the Voigt and Reuss models of summed stiffness and compliance. The compliance quasi-isotropic asymptote, which >'-:' has evidently not been discussed in the literature, is presented here with some useful . applications. The compliance computation is cast in the compact multiple-angle form, in analogy with the form used by many authors for laminate stiffness. Formulas for the two .... isotropic asymptotes are given, in terms of the basic mono-ply engineering parameters, to 20 DISTRIBUTION/ AVAILABILITY OF ABSTRACT 121 ABSTRACT SECURITY c{ASSIFICATION,.,'% 0 UNCLASSIFIED/UNLIMITED @1 SAME AS RPT CJ DTIC USERS Unclassified 22a NAME OF RESPONSIBLE INDIVIDUAL 122b TELEPHONE (Ifclude AreaCode) 22c OFFICE SYMBOL % % DD FORM 1473. 84 MAR 83 APR edition maybe used until exhausted. All other editions are obsolete SECURITY CLASSIFICATION OF THIS PAGE
doi:10.21236/ada192305 fatcat:24ytb5rqkff2nib5cqxgbyxeny