Study on the Mechanical Properties of Oblique Shear of UHPC-NC Composite Components

Wang Heng ； Li Mu ； Zhihe Sun ； Chengling Xu

《International Core Journal of Engineering》 8卷7期 (2022/07) Pp. 993-1006

https://doi.org/10.6919/ICJE.202207_8(7).0131

摘要

UHPC is widely used to reinforce all kinds of dilapidated bridges because of its super high strength and superior performance. However, due to the different shrinkage properties of UHPC, the interface strength of NC is different. Therefore, proper UHPC- CNC interface treatment method and stress state are an important prerequisite to ensure the performance of steel bars. In this paper, a finite element model of UHPC-NC composite members is established. By changing the bonding, damage, friction coefficient and interface angle, different interface treatment methods and different shear angles are simulated, so that the failure characteristics and mechanical response of UHPC-NC interface can be obtained. Through the test results, we found that the surface roughness of NC can greatly improve the bearing capacity of UHPC-NC. For example, the bearing capacity of the ＂chiseled＂ interface is 20% higher than that of ＂smooth＂ interface. At the same time, the smaller interface shear angle has less influence on the bearing capacity of the specimen. When the shear angle exceeds 30, the bearing capacity will decrease greatly. Finally, the reliability of the model is verified by comparing the simulation test results of two articles with the actual test data.

關鍵字

UHPC ； NC ； Oblique Shear Test ； Interface Processing ； Contact-separation Model ； Finite Element Method

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