A self-reinforced cementitious composite for building-scale 3D printing. (July 2018)

• Record Type: Journal Article
• Authors: Soltan, Daniel G.; Li, Victor C.
• Is Part Of: Cement & concrete composites. Volume 90(2018)
• Page Start: 1
• Page End: 13
• Publication Date: 2018-07
• Subjects: Printable concrete -- Printable ECC -- Strain-hardening cementitious composites -- Three dimensional printing -- Additive manufacturing; Composite-reinforced concrete -- Periodicals; Concrete -- Periodicals; Composite materials -- Periodicals; Composites de ciment -- Périodiques; Béton -- Périodiques; Composites -- Périodiques; Béton léger -- Périodiques; Cement composites; Composite materials; Composite-reinforced concrete; Concrete; Lightweight concrete; Periodicals; Electronic journals; 620.135
• DOI: 10.1016/j.cemconcomp.2018.03.017
• Languages: English
• ISSNs: 0958-9465

Abstract

Abstract: A design scheme for self-reinforced cementitious composites to be used for building-scale 3D printing processes is introduced. The design is based on that of engineered cementitious composites, which include dispersed short polymer fibers to generate robust tensile strain-hardening. The mechanical property profile of these printable ECC materials is meant to eliminate the need for steel reinforcement in printed structures, providing more freedom and efficiency for building-scale 3D printing processes. The fresh state rheological properties have been systematically manipulated to allow printability. Effects on fresh state workability of several compositional ingredients and processing parameters are investigated herein. To maintain consistent printing performance with a batch mixing approach, thixotropy in the fresh state is exploited to temporarily decouple hardening behavior from the processing timeline. Minimal workability loss under continued shear agitation is achieved. Mechanical properties of the printable materials are characterized and the printability of the materials is demonstrated. Highlights: Strain-hardening cementitious composites (SHCCs) compatible with large-scale 3D printing processes are developed. This family of printable SHCCs is based on the design and damage tolerance philosophy of "Engineered Cementitious Composites". Thixotropy is exploited to temporarily decouple hardening of the printable material from the processing timeline. Tensile strain-hardening behavior lends exceptional durability and resilience. The tensile properties of these printable SHCCs eliminates the need for extra reinforcement in printed structures and members.