Japanese rivers have steep gradients so that there are many geological formations where sediment disasters following heavy rains likely occur. One such sediment disaster is debris flow that flushes boulders down the river. It was to prevent such disasters that debris barriers were constructed throughout Japan as a part of erosion control projects. In order to protect these barriers from repeated erosion and damages from sediment flow, we have worked together with the Sabo & Landslide Technical Center and developed Rubber Steel, a composite material made by integrating rubber and steel plates to attach to concrete surfaces. Rubber steel helps prolonging the life cycle and reduces the running cost of various types of concrete structures.