本文从设计、建造及承载性能三方面开展了3D打印轻量化混凝土拱形结构的可行性研究。基于拱结构构造和3D打印工艺特点,提出了一种拱结构精准、快速拼装的方法；在此基础上建造了5根3D打印轻量化拱试件,通过试验研究了两点集中、三点集中和均布荷载三种工况以及“π形”、“W形”、“M形”三种截面打印路径对拱结构承载性能的影响规律,并借助有限元计算分析了矢跨比为1/4、1/6和1/8时3D打印混凝土拱结构的力学行为。结果表明,均布荷载下试件各节段的协同变形能力最好,承载能力最强,3D打印混凝土材料的抗压优势得以充分发挥；集中荷载易造成拱试件局部压溃,两点及三点集中荷载下的拱试件相对于均布荷载下的拱试件极限承载力分别下降30.2%和14.2%；采用“M形”横截面打印路径的试件传力效果最好,单位质量峰值荷载相较于打印路径为“π形”和“W形”的试件分别提升了23%和28%；在规范建议采用的矢跨比范围内,随着矢跨比的减小3D打印混凝土拱结构的承载力逐渐降低。本试验的5根试件均具有良好的承载性能,为轻量化拱形结构3D打印设计、建造及应用提供了参考。

This paper conducts a feasibility study on 3D printed lightweight concrete arch structures from three aspects: design, construction, and load-bearing performance. Based on the characteristics of arch structure and 3D printing technology, a segment-assembly method was proposed to realize the accurate and fast assembly of arch structure. On this basis, five 3D printed lightweight arch structure specimens were constructed. The influence of three conditions, namely two-point concentration, three-point concentration, and uniformly distributed load, as well as the printing paths of "π", "W", and "M" cross-sections, was studied through experiments on the bearing performance of arch structures. Additionally, the mechanical behavior of 3D printed concrete arch structures with

TU375.4

“十四五”国家重点研发计划项目课题(2023YFC3806902)；国家自然科学基金优秀青年科学基金(52178198)