UHPC-齿槽-灌浆套筒连接装配式RC梁抗弯承载力研究

Study on flexural capacity of prefabricated RC beams with UHPC-groove-grouting sleeve connection

装配式混凝土结构因其施工周期短、质量等级高、环境负载低等优点,近些年已经在世界范围得到了广泛应用,但如何提升预制构件间的连接性能和装配式结构的整体性一直是国内外学者研究的热点问题。鉴于此,本文结合湿式连接优异的连接性能和超高性能混凝土(UHPC)高强、高韧、与普通混凝土粘结性能优等特点,提出了一种UHPC-齿槽-灌浆套筒连接装配式RC梁的构造,建立了该装配式RC梁的ABAQUS有限元模型,并验证了模型的有效性。在此基础上,重点探究了节点参数和轴压比对UHPC-齿槽-灌浆套筒连接装配式RC梁抗弯承载力的影响。研究结果表明:文献试验模型与有限元模型结果的误差均在合理范围内,本文的有限元建模方法和参数选取原则较合理;UHPC-齿槽-灌浆套筒连接装配式RC梁的抗弯承载力高于现浇RC梁的抗弯承载力;在可用的节点参数范围内,榫长、榫宽、倾角、底板厚度以及UHPC宽度对装配式RC梁的抗弯承载力影响不显著;装配式RC梁的抗弯承载力和抗弯刚度均随着轴压比增大而增加。

Prefabricated concrete structure has been widely used in the world in recent years because of its advantages such as short construction period,high quality grade and low environmental load.However,how to improve the connection performance between prefabricated components and the integrity of the assembled structure has always been a hot topic for scholars at home and abroad.In view of this,combined with the excellent connection performance of wet connection and the high strength,high toughness and excellent bonding performance between ultra-high performance concrete(UHPC)and ordinary concrete,a UHPC-groove-grouting sleeve connection prefabricated RC beam structure is proposed,the prefabricated RC beams using ABAQUS finite element model is established,and the validity of the model is verified.On this basis,the influence of joint parameters and axial compression ratio on the flexural capacity of prefabricated RC beams with UHPC-groove-grouting sleeve connection is investigated.The results show that the errors between the experimental model and the finite element model are within a reasonable range,and the finite element modeling method and parameter selection principle in this paper are reasonable.The flexural capacity of the prefabricated RC beam with UHPC-groove-grouting sleeve connection is higher than that of the cast-in-place RC beam.Within the range of available joint parameters,the groove length,groove width,inclination angle,floor thickness and UHPC width have no significant effect on the flexural capacity of the prefabricated RC beam.The flexural bearing capacity and flexural stiffness of prefabricated RC beams increase with the increase of axial compression ratio.