| 摘要: |
| 制作普通矩形、密配筋矩形、打孔矩形、楔形和菱形5种类型的现浇超高性能混凝土（UHPC）接缝板试件，并对其进行抗弯试验，研究了配筋UHPC 普通混凝土（NC）湿接缝界面的抗裂能力、抗弯性能和破坏模式.通过轴拉试验探讨了NC表面处理方式、NC湿润度、UHPC养护龄期和养护方法等对UHPC NC界面抗裂性能的影响.结果表明：现浇UHPC与预制NC界面的开裂强度和抗弯承载力均优于完整的预制NC，大部分接缝板的破坏均发生在预制NC部分；粗糙或凹凸NC表面、湿润NC、60℃蒸汽养护均可显著提升界面的抗裂性能；养护龄期3～7d时，UHPC NC界面的抗裂强度可达到其28d强度的861%，而28d后UHPC NC界面的抗裂性能提升有限. |
| 关键词: 超高性能混凝土 普通混凝土 接缝 配筋UHPC NC界面 试验 抗弯 |
| DOI：103969/j.issn.1007 9629202103011 |
| 分类号: |
| 基金项目:国家自然科学基金资助项目（51778221）；广州市产业技术重大攻关计划项目（201902010019） |
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| Flexural Behavior and Influence Factors of Reinforcement Interface of UHPC Wet Joint |
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HUO Wenbin1, ZHANG Yang2, HUANG Longtian1, CHEN Bei2
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1.Guangdong Architectural Design & Research Institute Co., Ltd., Guangzhou 510010, China;2.College of Civil Engineering, Hunan University, Changsha 410082, China
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| Abstract: |
| The interfaces between five types of reinforcement ultra high performance concrete(UHPC) and normal concrete(NC) were evaluated with respect to their crack resistance, flexural capacity and failure modes by the flexural behavior tests, namely rectangular with holes, rectangular with high reinforcement, wedge shaped and diamond shaped reinforcement interfaces. The influences of treatments of NC surface, moisture degrees of NC, ages of UHPC and curing conditions on the crack resistance of UHPC NC interface were investigated by the NC UHPC NC specimens direct tensile tests. The results demonstrate that cracking strength and flexural capacity of the reinforcement interfaces between UHPC and precast NC are better than that in the intact NC deck. The failure occurs in the precast NC components in most cases. The roughened or concave convex NC surfaces, saturated by NC substrate and 60℃ steam curing can significantly improve the crack resistance of the interface, the 861% of 28d cracking strength of the UHPC NC interface can be achieved at the early age of 37d, and cracking strength developes slowly after 28d. |
| Key words: ultra high performance concrete(UHPC) normal concrete(NC) joint reinforcement UHPC NC interface experiment flexural |
