3D打印再生粗骨料混凝土抗冻性能试验研究  

Experimental study on frost resistance of 3D printed recycled coarse aggregate concrete

作　　者：刘超[1] 张治宁 刘化威 张韦 LIU Chao;ZHANG Zhining;LIU Huawei;ZHANG Wei(School of Science,Xi an University of Architecture and Technology,Xi an 710055,China;School of Civil Engineering,Xi an University of Architecture and Technology,Xi an 710055,China)

机构地区：[1]西安建筑科技大学理学院,西安710055 [2]西安建筑科技大学土木工程学院,西安710055

出　　处：《功能材料》2023年第7期7001-7009,共9页Journal of Functional Materials

基　　金：国家自然科学基金项目(52178251);“十三五”国家重点研发计划项目(2019YFC1907105);西安市科技计划重点产业链核心技术攻关项目(2022JH-ZCZC-0026);陕西省杰出青年科学基金项目(2020JC-46)。

摘　　要：3D打印技术在建筑领域得到显著发展,为解决混凝土3D打印行业实现可持续发展。通过对再生粗骨料(RCA)取代率为0%、50%、100%的3D打印试件和铸模试件进行抗冻性能研究,结合3D打印再生粗骨料混凝土(3DPRAC)界面过渡区的电镜扫描分析其劣化成因。结果表明,在前200次冻融循环中RCA的掺入并没有明显降低3D打印混凝土的质量和动弹模量;在600次冻融循环后RCA为100%掺量的3D打印再生混凝土抗冻性能表现优于RCA掺量为50%。基于3D打印再生混凝土逐层堆叠的建造特点,提出了3DPRAC孔隙区域集中分布模型,揭示了3DPRAC冻融损伤劣化机理。建立的冻融损伤模型能够较好地反映3DPRAC抗冻性能变化规律。3D printing technology has been significantly developed in the construction field,and in order to address the concrete 3D printing industry to achieve sustainable development,this paper analyzes the causes of deterioration by conducting freezing resistance studies on 3D printed specimens and cast specimens with 0%,50%,and 100%recycled coarse aggregate(RCA)substitution,combined with electron microscopy scans of the transition zone at the interface of 3D printed recycled coarse aggregate concrete(3DPRAC).The results showed that the incorporation of RCA in the first 200 freeze-thaw cycles did not significantly reduce the mass and dynamic modulus of 3D printed concrete;after 600 freeze-thaw cycles the 3D printed recycled concrete with 100%RCA incorporation performed better than that with 50%RCA incorporation in the freeze-thaw cycles.Based on the construction characteristics of 3D printed recycled concrete stacked layer by layer,a 3DPRAC pore area concentration distribution model was proposed to reveal the 3DPRAC freeze-thaw damage deterioration mechanism.The established freeze-thaw damage model can better reflect the change pattern of 3DPRAC freeze-resistance performance.

关 键 词：3D打印混凝土 再生粗骨料 冻融循环 微观结构 冻融损伤模型 

分 类 号：TU528[建筑科学—建筑技术科学]