2. Long glass fibres (Young's modulus of 80 GPa, Poisson's ratio of 0.25) are added as a reinforcement to a polymeric ma
Posted: Sat May 21, 2022 8:29 am
2. Long glass fibres (Young's modulus of 80 GPa, Poisson's ratio of 0.25) are added as a reinforcement to a polymeric matrix (Young's modulus of 1 GPa, Poisson's ratio of 0.30) in order to produce an advanced composite material. The volume fraction of fibres is 20%. The fibres are aligned along the longitudinal direction of the composite. (a) Calculate the Young's modulus of the composite material along its longitudinal and transverse direction. (5 marks) (b) Calculate the longitudinal and transverse strain in the composite material, when a stress of 400 MPa is applied along the longitudinal direction of the composite. At that stress level, the material remains in the elastic regime. (7 marks) (c) Calculate the stored elastic energy per unit volume in the matrix and in the fibres at that level of stress. (8 marks)