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Tinghong Pan

Publications and source records attributed to Tinghong Pan.

2 recordsLinked to original sources

Effect of shaping plate apparatus on mechanical properties of 3D printed cement-based materials: Experimental and numerical studies

Precisely controlling the shape of the printed-layers, eliminating the curved sides and internal stress concentration, and increasing the mechanical properties are essential to guarantee the quality of 3D printed cement-based structures. This work aims at achieving the above-mentioned targets through a specially designed shaping plate apparatus. The pressure (stress) distribution in the printed structure with a shaping plate apparatus (SP-3DPC), and the cross-sectional shape, microstructure and mechanical properties of SP-3DPC were systematically investigated. Results indicate that using the shaping plate apparatus may slightly reduce the printing speed, but it can effectively constrain the free expansion of extrudate, control its cross-sectional geometry, and improve the surface finish quality and mechanical properties of the printed structure. This study provides a theoretical basis and technical guidance for the design and application of the shaping plate apparatus.

physics.app-ph

Interlayer bonding investigation of 3D printing cementitious materials with fluidity retaining polycarboxylate superplasticizer and high dispersion polycarboxylate superplasticizer

Proposed special requirements exist for the rheological properties and time varying characteristics of 3D printing cementitious materials (3DPC). In this study, high dispersion polycarboxylate superplasticizer (HD PC) and fluidity retaining polycarboxylate superplasticizer (FR PC) were used to control the rheological behaviors of 3DPC. The correlation of the time interval, the time varying characteristics of the rheological properties and the interlayer bonding strength were investigated. The results indicated that FR PC improved the fluidity retention ability and thixotropy of the fresh pastes. The thixotropic hysteresis loop area and reflocculation rate (Rthix) of FR PC were 101.9% and 80.4% higher than those of HD PC, respectively. Furthermore, the FR PC polymer has a positive effect on the interlayer bonding and may reduce the negative effect caused by extending the time interval. During the time interval of 20 s to 30 min, the interlayer bonding strength with FR PC decreases by 14.1%, while that with HD PC decreases by 50.0%.

physics.app-ph