Effects of Using Silica Fume as a Viscosity Modifier on the Properties of 3D Printable Concrete

Purpose: The development of 3D printable concrete (3DPC) necessitatesan intimate tailoring of various properties that are rather contradictory.Hence, many studies employed chemicals like Hydroxypropyl Methylcellulose thatadversely affect the hardened properties of these mixtures. Thus, in thisstudy, the feasibility of using silica fume (SF) as an alternative viscositymodifier has been studied. Studydesign/methodology/approach: SF was usedin various dosages such as 14%, and 18% by weight of cement. The effect of SFaddition on fresh and hardened properties of 3DPC was investigated.Accordingly, fresh properties like workability and green strength of 3DPC mixtureswere studied. Additionally, hardened properties such as compressive andflexural strengths at 7 and 28 days were performed on molded and standard curedsamples.Findings: As a result, it has been determined that while theutilization of SF enhanced the hardened properties of 3DPC mixtures, it significantlyimproved their fresh properties Additionally, its usage led to the decrease insetting times of developed mixtures in direct proportion to its dosage. Originality/value: The utilization of SF in the development of 3DPCcontributes to the knowledge of how to prevent deformation and structuralissues during the early stages of printing, curing, and improving the overallintegrity of printed structures. The benefits of SF on the compressive strengthof 3DPC highlight the long-term viability of structures constructed using thistechnology.