An H4bW4 road restraint system has been installed in Bulgaria for the first time. In late March, the first 520 meters of this steel safety barrier—unique to the country—were installed to protect a railway overpass pier spanning Road II-21 (Ruse–Silistra). According to crash test results obtained during the system’s certification, it can withstand an impact from a truck with a gross weight of 38 tonnes or an impact energy of 725 kJ. Unlike the previously used H4bW7 systems, which involve an expected displacement of over 2 meters, the new system limits deformation to a maximum of 1.3 meters. This makes it exceptionally suitable for protecting piers, abutments, and other obstacles located near the roadway.
