Feasibility Study of the Use of Polymer-Modified Cement Composites as 3D Concrete Printing Material

Kim²,

et al. 2019

Materials

Self Cite

The compressive and flexural strengths of mortars modified with ethylene-vinyl acetate (EVA) were experimentally investigated for use in three-dimensional (3D) additive construction (3DAC). EVA powder, which is available in a premix type, was employed as an admixture. The test results for the cast specimens showed that, at a curing age of 28 days, the compressive strengths ranged from 32.92 MPa to 43.50 MPa, and the flexural strengths ranged from 12.73 MPa to 14.49 MPa. The compressive and flexural strengths of the printed specimens were relatively lower: 23% to 26% and 3% to 7%, respectively. The compressive strength also decreased and the flexural strength increased when the EVA/cement ratio was increased. The results of the experiment reveal that the EVA-modified mortar had a high rate of strength development early on, making the material advantageous for use in 3DAC. It was determined that the appropriate EVA/cement ratio ranged between 5% and 15%. However, the printed specimens exhibited lower compressive and flexural strengths than did the cast specimens, and the compressive strength decreased as the EVA content was increased. This study provides the compressive and flexural strengths of common EVA-modified mortars, important data for 3DAC applications.

Section: Introductionmentioning

confidence: 99%

Compressive and Flexural Strengths of EVA-Modified Mortars for 3D Additive Construction

Kim²,

et al. 2019

Materials

Self Cite

“…Yeon et al [8] examined the feasibility of using a polymer-modified cement composite, comprising Portland cement, fly ash, blast furnace slag, silica fume and a water-soluble polymer. The fresh properties studied were flowability, extrudability, open time, and buildability.…”

Section: Literature Reviewmentioning

confidence: 99%

3D Printable Composites for Productive and Sustainable Built Environment

Wong¹,

Tan²,

Leong³

et al. 2019

IJET

This paper reports the development of 3D printable composites and laboratory-scale 3D printing technology, which are capable of producing building and construction components of properties and performance comparable to conventional casting methods. The slump test was carried out to examine the consistency and workability of fresh 3D printable eementitious mixtures; whereas the hardened density and compressive strength measurements were conducted to assess the performance of hardened 3D printable cementitious composites.

“…ACE technology can be broken down into the following independent components: 3D printers, modeling software, and printing materials (i.e., mortar). The major study areas associated with ACE can be classified into the machine, 3D modeling, and material areas [8]. Among these three research fields, few studies have been conducted on printing materials, especially as compared to the mechanical and modeling aspects.…”

Section: Introductionmentioning

confidence: 99%

Fresh Properties of EVA-Modified Cementitious Mixtures for Use in Additive Construction by Extrusion

Kim²,

et al. 2019

Materials

Self Cite

In this study, the fresh properties of ethylene–vinyl acetate (EVA)-modified cementitious mixtures were experimentally investigated to evaluate the feasibility of this type of material being used in additive construction by extrusion (ACE). The EVA/cement ratio was a main variable to determine the properties, including flowability, extrudability, buildability, and open time. According to the flow test results, the optimized flow of the EVA-modified cementitious mixtures was found to be 65% for buildability. This excellent flowability could be achieved because the flow increased as the EVA/cement ratio increased; conversely, the extrudability was slightly reduced when the EVA/cement ratio increased. However, if the flow of the EVA-modified cementitious mixtures was maintained at 65%, ACE could be achieved without significant issues. In addition, the height of the additive concrete walls created was not substantially reduced after printing of these mixtures, even though different EVA/cement ratios were applied. Plus, ACE can be operated longer with such mixtures because the open time becomes longer as the EVA/cement ratio increases. In summary, the results clearly demonstrated that EVA-modified cementitious mixtures were feasible for use as ACE materials.