Wang Ziyue, Chen Zixuan, Xiao Jianzhuang, Ding Tao
College of Civil Engineering, Tongji University, Shanghai, China.
Key Laboratory of Performance Evolution and Control for Engineering Structures of Ministry of Education, Tongji University, Shanghai, China.
3D Print Addit Manuf. 2024 Jun 18;11(3):e1162-e1174. doi: 10.1089/3dp.2022.0338. eCollection 2024 Jun.
A novel shear test method on shear bond behavior of 3D printed interlayer interfaces and interstrip interfaces was proposed in this study. Thereafter, the effect of different replacement ratios of recycled sand, printing intervals, and surface treatments were investigated. The test results showed that under the same printing condition, the interfacial shear strengths of interlayer interface and interstrip interface were similar to each other. The interfacial shear strength slightly decreased with the increase of the replacement ratio of recycled sand, while it sharply decreased with the extension of printing interval time. The interfaces in 3D printed recycled mortar had higher time sensitivity compared with 3D printed natural mortar. Considering that discontinuous construction will introduce inferior interfaces in 3D printed concrete components, effective surface treatments should be conducted. According to the test results, the improvement effect of surface treatments was epoxy paste > cement paste > surface wetting > no treatment.
本研究提出了一种针对3D打印层间界面和条带间界面剪切粘结性能的新型剪切试验方法。此后，研究了再生砂不同替代率、打印间隔和表面处理的影响。试验结果表明，在相同打印条件下，层间界面和条带间界面的界面抗剪强度彼此相似。界面抗剪强度随再生砂替代率的增加而略有降低，而随打印间隔时间的延长而急剧降低。与3D打印天然砂浆相比，3D打印再生砂浆中的界面具有更高的时间敏感性。考虑到间断施工会在3D打印混凝土构件中引入劣质界面，应进行有效的表面处理。根据试验结果，表面处理的改善效果为：环氧胶泥>水泥浆>表面湿润>未处理。
