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The number of articles available in Google Scholar after entering the keywords presented in the table (Google Scholar)
| 1 keyword | The number of papers |
| Concrete | 1 490 000 |
| Fibers | 17 900 |
| 3D-printing | 17 900 |
| Shotcrete | 27 200 |
| 2 keywords | The number of papers |
| Concrete + Fibers | 117 000 |
| Concrete + 3D-printing | 42 800 |
| 3D-printing + Shotcrete | 2030 |
| Fibers + Shotcrete | 16 000 |
| Fibers + 3D-printing | 35 800 |
| Concrete + Shotcrete | 19 500 |
| 3 keywords | The number of papers |
| Concrete + Fibers + 3D-printing | 17 500 |
| Fibers + 3D-printing + Shotcrete | 1350 |
| Concrete + 3D-printing + Shotcrete | 1910 |
| Concrete + Fibers + Shotcrete | 15 300 |
| 4 keywords | The number of papers |
| Concrete + Fibers + 3D-printing + Shotcrete | 1260 |
A qualitative comparison of fiber-reinforced and plain UHPC mixes (Senapathi & Peiris, 2025; Wang & Gao, 2016)
| Criteria | UHPFRC | UHPC |
|---|---|---|
| Workability | Reduced | High |
| Porosity | May increase or decrease depending on fiber type | Very low |
| Flowability | Decrease | Highest flowability |
| Air content | Reduced content | High content |
A qualitative comparison of hardened fiber-reinforced concrete compared to plain concrete (Senapathi & Peiris, 2025)
| Criteria | UHPFRC | UHPC |
|---|---|---|
| Failure mode | Ductile failure | Brittle failure |
| Tensile strength | Significantly increased | Lower |
| Impact resistance | High | Low |
| Crack patterns before localization | Multiple cracks | One single, well-defined crack |
| Post-cracking load capacity | Distinct post-cracking load capacity | No significant post-cracking strength |
| Crack initiation location | Cracks are bridged by fibers | Points of stress concentration in the matrix |
A qualitative comparison between shotcrete-based 3D printing and extrusion-based 3D printing (Dörrie et al_, 2025; Heidarnezhad & Zhang, 2022; Liu et al_, 2025)
| Criteria | Shotcrete Based 3D Printing | Extrusion Based 3D Printing |
|---|---|---|
| Material deposition method | High-pressure spraying | Material extruded through a nozzle |
| Printing speed | Very high | Lower, limited by pump speed |
| Cold joint formation | Lower risk | Higher risk of cold joins between layers |
| Geometric precision | Lower, strongly dependent on spray pattern, spray angle, standoff distance | Higher and easier to control |
| Geometric freedom | Greater directional flexibility of material application | Limited geometric freedom, complex freeform shapes require supports |
| Surface quality | Lower, prone to rebound and overspray | Higher, surfaces are smoother |
| Ability to print large volumes quickly | Excellent | Limited |
| Surface finish | Rough | Smooth |
| Robot control | More complex | More predictable |
| Reinforcement integration | Possibility of integrating continuous reinforcement using different techniques | Commonly used as lost formwork, limited reinforcement integration |
| Sensitivity to mix inconsistencies | High sensitivity, requires digital control | Lower, process is more predictable |
| Anisotropy | Lower, due to continuous compaction | Significant material anisotropy |
| Material-process interaction | Strongly coupled material-process interaction | Geometric characteristics determined by nozzle size |
| Design implication | Greater directional flexibility | Geometric freedom is limited |