Engineers from Purdue University (West Lafayette, Indiana, USA), in collaboration with concrete additive manufacturing standup RCAM Technologies (Irvine, California, USA) and the Floating Wind Technology Company (FWTC), have undertaken a project to develop offshore wind tower parts using 3D-printed concrete.
Traditional methods of building wind turbines are expensive due to the necessity for parts made from steel materials. However, according to Pablo Zavattieri, a professor in Purdue’s Lyles School of Civil Engineering, “finished steel structures are much more expensive than concrete.” This cost is further compounded by the expense to ship part that are at least 30 miles away from a coast.
For this reason, the Purdue research project—funded by the National Science Foundation INTERN program—are investigating methods of making these parts from 3D concrete, a less expensive material with the ability to float to a site from an offshore plant. In addition, 3D printing eliminates the need for the costly molds used in conventional concrete manufacturing.
The group’s current research scales up their 3D-printing process by formulating a special concrete made from a mixture of cement, sand, and aggregates, along with chemical admixtures to control shape stability when concrete is still fresh. The team’s goal is to understand the feasibility and structural behavior of 3D-printed concrete produced on a large scale.
This latest project is a continuation of the research team’s previous work on 3D-printing cement-based materials into bioinspired designs, which includes a 3D-printed cement past that mimics the resilient shells of arthropods such as beetles and lobsters. “The idea we have for this [current] project is to scale up some of the bioinspired design concepts we have proven on a smaller scale with the 3D printing of cement paste and to examine it on a larger scale,” says Mohamadreza “Reza” Moini, a Ph.D. candidate in civil engineering at Purdue.
8-Other projects the research team is looking into include the integration of a robot arm with a concrete pump to fabricate the wind turbine subcontractors and anchors, as well as 3D-printed concrete structures involving wind turbine towers and anchors. Both RCAM and FWTC have an interest in seeing such structures developed, according to the university.
“Purdue’s world-class capabilities and facilities will help us develop these products for offshore products for the U.S. Great Lakes, coastal and international markets,” says Jason Cotrell, chief executive officer of RCAM Technologies. “Our industry also needs universities such as Purdue to provide the top-quality university students for our workforce needs for these cutting edge technologies.”