Close cell structured foams are made by incorporation of cenospheres in polymeric materials. Low moisture absorption characteristics and considerably higher compressive strength of these materials compared to open cell structured foams make them suitable for use as core materials in sandwich structured materials. Incorporation of cenospheres in the epoxy resins enhances their impact strength and damage tolerance, especially if these materials are used in sandwich configurations. Present study analyzes and compares the effect of incorporation of cenospheres like flyash and glass microballoons in the epoxy resins on the deformation and fracture behavior of the material. Approach based on determination of local stress intensity factors is used to obtain estimate of the stresses in the material.