Improvements in materials and the availability of apparatus enabling mechanical, strength, thermal testing of sandwich structures, including fatigue tests, allow for a dynamic development of research work confirming the effectiveness of the use of structural composites as energy-intensive structures. This paper presents the results of selected strength tests of a layered epoxy-glass composite with a polyurethane-modified matrix and a porous core. The conducted experimental studies were proposed as a basis for the creation of a test procedure for comprehensive strength and mechanical characterisation of the composite. Obtaining a layered material with a modified matrix is a formative factor for impact energy absorption properties. The quantitative and qualitative effects of material selection and matrix modification on impact properties were characterised, and an analysis of composite damage and component interaction under loads occurring during the proposed experimental tests was carried out.