The history of mixing and the history of the manufacture of concrete go back a long way. Even the Romans had the so-called opus caementitium, nowadays known as Roman concrete. This was used to manufacture compressively strong structural components from water-resistant mortar and stone chippings. Probably the most famous building constructed with Roman concrete is the Pantheon (fig. 1), whose dome spans 43 m . Even today we are still striving for ever greater heights and spans in buildings. The development of continually better building materials goes hand-in-hand with the drive towards the ever larger. Hence, over the course of time the compressive strength of concrete has been continuously increased, which has ultimately led to a completely newly-developed building material, ultra-high performance concrete (UHPC for short).