AbstractFurther implications of equations for the directional dependence of swelling1documentclass{article}pagestyle{empty}begin{document}$ atheta ^2 = left( {a_{T^2 } - a_{L^2 } } right)sin ^2 theta + a_{L^2 } $end{document}and elastic modulus2documentclass{article}pagestyle{empty}begin{document}$ {1 mathord{left/ {vphantom {1 {E_theta }}} right. kern-nulldelimiterspace} {E_theta }} = left( {cos ^2 {theta mathord{left/ {vphantom {theta {E_L }}} right. kern-nulldelimiterspace} {E_L }}} right) + left( {sin ^2 {theta mathord{left/ {vphantom {theta {E_T }}} right. kern-nulldelimiterspace} {E_T }}} right) $end{document}which were originated by Coran, Boustany, and Hamed1are given. Equation (1) is practically equivalent to the standard tensor transformation equation assuming that swelling is equivalent to negative hydrostatic pressure and the new relationshipdocumentclass{article}pagestyle{empty}begin{document}$ frac{{a_L - 1}}{{a_{T - 1} }} approx frac{{E_T left( {1 - 2v_{LT} } right)}}{{E_L left( {1 - v_{TT} } right)}} $end{document}is derived for the caseE1≫E2. A corollary of eq. (1),3documentclass{article}pagestyle{empty}begin{document}$ {1 mathord{left/ {vphantom {1 {G_{LT} }}} right. kern-nulldelimiterspace} {G_{LT} }} = {1 mathord{left/ {vphantom {1 {E_T }}} right. kern-nulldelimiterspace} {E_T }} + {{left( {1 + 2v_{LT} } right)} mathord{left/ {vphantom {{left( {1 + 2v_{LT} } right)} {E_L }}} right. kern-nulldelimiterspace} {E_L }}, $end{document}conflicts with three commonly used models of unidirectional composites. Anisotropic laminate theory is used to show that eq. (3) has important consequences for multiply laminates with no triangulation. These results indicate that the equations of Coran et al. cannot be expected to have wide application to other systems, especially continuous cord‐reinforced rub
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