Blockmaxx – Mobile heavyweight-concrete vehicle barrier for urban security
Securing urban spaces is one of the most important municipal tasks and is preferably realized by means of mobile vehicle barriers that often resemble a fortress. The newly developed Blockmaxx barrier (3.7 t – 1.6 m x 1.0 m x 0.85 m) demonstrates how urban security can be reconciled with modern urban architecture.
Conventional construction materials are used in the production of the heavyweight-concrete base and ordinary-concrete top. The specially developed heavyweight-concrete formulation ensures high bulk density, high compressive and flexural strengths at a low dynamic modulus of elasticity, short setting times and high early strengths. Added steel fibers retard fatigue under highly dynamic loading, while high ductility prevents sudden failure or the detachment of concrete fragments.
Based on various impact scenarios, a cuboid element was realized that opens upon vehicle impact and unfolds the intended barrier effect in the final position. The complex functional mechanisms were designed by means of FEM simulations in order to calculate and analyze the correct displacement of the individual components.
At the end of 2021, the Blockmaxx barrier passed the two required crash tests with different approach scenarios, thus becoming the third system in Germany to obtain full certification (TR DHPol – protection class SK1B). As in the simulation, the colliding truck (12 t, collision speed 44 km/h) was lifted, came to a stop within 28 m, and was immobilized. At a kinetic impact energy of approx. 900 kJ, only minor spalling was detected on the Blockmaxx barrier thanks to the special coating and fiber-reinforced heavyweight concrete.
The Blockmaxx barrier will be used in the future to safely cordon off urban spaces. Moved into position quite easily by means of cranes or lift trucks, it blends in inconspicuously with the cityscape and event concepts. When planted, it becomes a permanent piece of street furniture. Using it as a conventional advertising medium is also conceivable and will create an added value.
