Porous materials such as polymeric foam are widely adopted in engineering and biomedical fields. Porous materials often exhibit complex nonlinear behaviors and are sensitive to material and environmental factors including cell size and shape, amount of porosity, and temperature, which are influenced by the type of base materials, reinforcements, method of fabrication, etc. Hence, the material characteristics of porous materials such as compressive stress-strain behavior and void volume fraction according to aforementioned factors should be precisely identified. In this study, unconfined uniaxial compressive test for two types of closed-cell structure polyurethane foam, namely, 0.16 and 0.32 g/cm3 of densities were carried out. In addition, the void volume fraction of three different domains, namely, center, surface and buckling regions under various compressive strains (10%, 30 %, 50 % and 70 %) were quantitatively observed using Micro 3D Computed Tomography(micro-CT) scanning system. Based on the experimental results, the relationship between compressive strain and void volume fraction with respect to cell size, density and boundary condition were investigated.

Generally, antiseptic synthetic woods are used in septic environment because of their durability and relatively fine view. However, they have problems such as a failure of connection between the members under the septic conditions. In this study we investigate a fiber reinforced polyurethane foothold to be used in the wet environment to replace the synthetic wood. The fiber reinforced polyurethane foothold is consist of 2 different layer of materials. First layer is a glass fiber reinforced polymeric plastics (GFRP) which is located at outer surface of the foothold. This GFRP outer layers carry most parts of load. Second layer is a polyurethane layer which transfers the load to each outer layer. Flexural tests for this foothold are conducted. From the flexural tests it is confirmed that the structural performance of foothold test specimen with different number of GFRP layers and density of the polyurethane.

In this study, the chemical resistance of polyurea resin waterproofing and anti-corrosion materials that is applied to the social infrastructure was analyzed. Mostly, there are three the main materials which is polyurea resin waterproofing and anti-corrosion, polyurea resin waterproofing and anti-corrosion, polyurethan-polyurea waterproofing and anti-corrosion, and polyurethane waterproofing and anti-corrosion were analyzed as the specimen. As a result of chemically resistant characteristic to three kinds of polyure type materials, it’s polyurethane, polyurea-urethane, and polyurea were arranged in the order. This order is generally predictable order that is expected by any user, but it was settled first by the quantitative evidence of chemical evaluation in this time. And, the result in this study will be utilizing as a basic data for establishing the quality standards which are able to judge the chemically resistant characteristic of polyurea resin waterproofing and anti-corrosion materials.