Unlike most of the classical approaches which resort to phenomenological criteria for describing the u1timate behaviour of composite materials, the implementation of a homogenization procedure within the framework of the yield design theory makes it possible to construct such a criterion in a rigorous way. A general formu1ation of the macroscopic strength condition for fibre reinforced composite materials is thus derived from the sole knowledge of the strength properties of their constituents (matrix and fibres) and of their structural arrangement as well. Moreover, the possibility of failure taking place only between matrix and fibres can be easily accounted for through the introduction of a decohesion criterion which limits the normal tensile stress component acting upon the interfaces. As a final outcome, a closed form failure condition which involves only a few parameters, relating respectively to the strength properties of each individual component, is proposed for mode1ling multidirectional reinforced composites with any volume percentage of fibres. A first comparison between theoretical predictions and several experimental data concerning both uniaxial and biaxial tests carried out on composite specimens proves to be quite satisfactory. The approach presented here outlines a possible method for designing composite structures against failure.
A homogenization approach to the yield strength of composite materials
TALIERCIO, ALBERTO
1991-01-01
Abstract
Unlike most of the classical approaches which resort to phenomenological criteria for describing the u1timate behaviour of composite materials, the implementation of a homogenization procedure within the framework of the yield design theory makes it possible to construct such a criterion in a rigorous way. A general formu1ation of the macroscopic strength condition for fibre reinforced composite materials is thus derived from the sole knowledge of the strength properties of their constituents (matrix and fibres) and of their structural arrangement as well. Moreover, the possibility of failure taking place only between matrix and fibres can be easily accounted for through the introduction of a decohesion criterion which limits the normal tensile stress component acting upon the interfaces. As a final outcome, a closed form failure condition which involves only a few parameters, relating respectively to the strength properties of each individual component, is proposed for mode1ling multidirectional reinforced composites with any volume percentage of fibres. A first comparison between theoretical predictions and several experimental data concerning both uniaxial and biaxial tests carried out on composite specimens proves to be quite satisfactory. The approach presented here outlines a possible method for designing composite structures against failure.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
