By Matthew Marani
Concrete is a ubiquitous building material, applied to the bulk of contemporary construction projects. While the sedimentary aggregate is commonly used due to its impressive compressive strength, it remains a brittle material subject to damage or failure during extreme environmental events such as earthquakes. In response to this inherent weakness, a team of researchers based out of Purdue University’s Lyles School of Civil Engineering comprising professors Jan Olek, Pablo Zavattieri, Jeffrey Youngblood, and Ph.D. candidate Mohamadreza Moini has developed a 3-D-printed cement paste that actually gains strength when placed under pressure.
The project, initiated in August 2016 with funding from the National Science Foundation, looked towards the natural durability and flexibility of arthropod shells. “The exoskeletons of arthropods have crack propagation and toughening mechanisms,” said Pablo Zavattieri, both of which can be reproduced “in 3-D-printed cement paste.”
For the prototype, the research team cycled through a number of geometric configurations, including compliant, honeycomb, auxetic, and Bouligand designs. Each of these formats responds to external pressures differently; a compliant design acts as a spring under stress while the Bouligand boosts crack resistance.
Read the full story HERE >>>> Source: ArchPaper Flexible 3-D-printed cement stretches the possibilities of construction