打印工艺对3D打印混凝土层间黏结性能研究北大核心CSCD

泵送挤出堆叠成型的打印工艺致使3D打印混凝土层间黏结性能成为结构分析要点。本文针对打印工艺参数并统计国内外试验数据,分析了3D打印混凝土层间弱黏结的影响机制,结合水泥水化过程建立了层间黏结强度随打印时间间隔的分阶段变化模型,明确了喷嘴形状、尺寸和高度对层间黏结的影响规律,提出了层间黏结强度随打印速度的退化模型,为3D打印混凝土工艺优化和流程改进提供理论参考和技术借鉴。

Influence of printing process on interlayer bonding properties of 3D printing concrete

For 3D printing concrete produced by a printing process of pumping, extrusion and stacking-up layer by layer, its interlayer bonding performance is a key point in structural analysis. This paper presents a statistical comparison and analysis of the interlayer bonding properties based on the previous test data in literature, and reveals the mechanism of interlayer bonding influenced by the parameters of the printing process. A two-stage model considering hydration process is developed to simulate the variations in interlayer bonding strength with the printing time interval; the influences of nozzle shape, size and height on interlayer bonding are clarified. We construct a model of interlayer bonding strength degrading with printing speed to optimize and improve the 3D printing process of concrete.