3D concrete printing
Researchers at Loughborough University in the U.K. have come up with a technique for extruding concrete to create 3D structural elements. They call this concrete printing, which uses a type of concrete that is precisely deposited under computer control from a CAD model through small extrusion nozzles. The “additive manufacturing technique” builds up shapes one small ribbon at a time. They say it “literally breaks the mold of traditional construction techniques by avoiding the need for formwork.” This could be the future of precasting. For more information, go to www.buildfreeform.com.
Cemex has come out with what they call Hidratium self-curing concrete. This is a branded ready-mix concrete that achieves its self-curing properties through “distinctive mix design principles and proprietary admixtures.” Although we may suspect that it incorporates some saturated lightweight aggregate or a superabsorbent polymer, or both, we’ll have to wait and see: It has been introduced in countries from China to Germany to Mexico, but not yet in the United States.
Rebar caps, or more formally impalement protection covers, have been around for many years and are OSHA-required. Now we have a better version known as the Springard. The plastic used is light and designed to mimic the structure of bones, with interior cavities. It also includes a steel plate and a rubber energy-absorbing material. A worker falling onto the Springard would be relatively uninjured due to its soft material and crumple zone. Testing on these devices originally was done with turkeys dropped from 8 feet. Learn more at www.concreteaccessories.com.