Structural-statistical analysis of the strain properties of laminated reinforced plastics

Conclusion The structural relations derived here make it possible to analytically predict the main statistical characteristics of the strain properties of an LRP with allowance for the mutual correlation of the random parameters of the structure. Use of the proposed relations is valid for studying combination loading (bending and a plane stress state), as well as when the structure of the composite is unbalanced. We evaluated the scale effect associated with the presence of multiple layers and determined the impact of this effect on the scatter of the strain properties of the LRP for different types of deformation. We also proposed a method of determining the actual statistical characteristics of layers indirectly — on the basis of experimental testing of multilayered unidirectional plastics. One promising prospect is the use of these results to formulate and solve problems involving optimization of the structure of LRP's on the basis of criteria ensuring the composite's reliability and dimensional stability. Finally, the results can also serve as a basis for establishing scientifically substantiated safety factors for stiffness.Translated from Mekhanika Kompozitnykh Materialov, No. 6, pp. 995–1001, November–December, 1990.