STRESS-CONCENTRATIONS DUE TO THERMAL LOADS IN COMPOSITE-MATERIALS

The thermal stress concentration at the surface of the composite is an alyzed using the ADINA program. The fibres in the composite are assume d to be arranged in a regular array. Making use of symmetry only one c ell of such an array is considered. When a composite is cooled down, a high tensile radial stress is detected at the interface, creating a c ondition for crack initiation at this location. Numerical experimentat ion, using various meshings, reveals that the magnitude of this stress depends on the size of element used, indicating a stress singularity. The order of the singularity is determined numerically and appears to be different for different stress components.