王强, 梁栩华, 刘鑫,等.节点加强下UHPC加固RC方柱抗震性能[J].河南理工大学学报（自然科学版）,doi:10.16186/j.cnki.1673-9787.2023070033.

WANG Q, LIANG X H, LIU X,et al.Seismic performance of concrete square columns strengthened by UHPC with joints strengthened[J].Journal of Henan Polytechnic University(Natural Science) ,doi:10.16186/j.cnki.1673-9787.2023070033.

节点加强下UHPC加固RC方柱抗震性能（网络首发）

王强1,2, 梁栩华2, 刘鑫2, 朱万旭1,2, 卢春玲1,2

 1. 广西绿色建材与建筑工业化重点试验室, 广西 桂林 541004;2. 桂林理工大学 土木与建筑工程学院, 广西 桂林 541004

摘要:为解决超高性能混凝土(UHPC)在加固钢筋混凝土柱中与基础脱粘的问题，提出了节点加强下采用UHPC对钢筋混凝土方柱进行加固的方法，为验证该加固方法的有效性，设计并制作了4个试件，以加固与否、轴压比为参数，对各试件的延性、耗能、承载力等抗震性能指标进行分析。试验结果表明:加固柱的延性系数、耗能最高提升了15.6%、76.4%，承载力最高提升了34.5%，并且加固柱滞回曲线的捏拢效应有所改善;随着轴压比提高，试件的承载力呈上升趋势，但延性和耗能均有所下降。这是由于采用节点加强可以增大UHPC加固层与基础底座的粘结应力，使UHPC加固层与核心混凝土共同受力;此外UHPC加固层可以限制混凝土的开裂和纵筋的屈曲。最后提出了一种基于平截面假定的UHPC节点加强加固柱压弯承载力计算方法,计算结果与试验结果的比值均大于0.85，具有较高的精度，验证了该计算方法的合理性。研究成果可为节点加强下UHPC加固RC方柱的工程应用及设计提供参考。

关键词:节点加强;UHPC加固;RC方柱;抗震性能;压弯承载力

中图分类号：TU352.11;TU375.3

doi:10.16186/j.cnki.1673-9787.2023070033

基金项目:国家自然科学基金资助项目（52068014）；广西自然科学基金资助项目（2023GXNSFAA026337）

收稿日期:2023-07-20

修回日期:2023-10-07

网络首发日期:2023-11-30

Seismic performance of concrete square columns strengthened by UHPC with joints strengthened（Online）

WANG Qiang1,2, LIANG Xuhua2, LIU Xin2, ZHU Wanxu1,2, LU Chunling1,2

1.Guangxi Key Laboratory of Green Building Materials and Construction Industrialization， Guilin  541004， Guangxi， China；2.College of Civil and Architecture Engineering， Guilin University of Technology， Guilin  541004， Guangxi， China

Abstract:In order to solve the problem of debonding between ultra-high performance concrete（UHPC） and the base of reinforced concrete columns， a method of strengthening reinforced concrete square columns by UHPC with joints strengthened was proposed. To verify the effectiveness of this reinforcement method， four specimens were designed and fabricated. The seismic performance indicators such as ductility， energy dissipation and bearing capacity were analyzed for each specimen with different parameters including reinforcement and axial compression ratio. Results showed that the ductility coefficient and energy dissipation of strengthened columns increased by 15.6% and 76.4%， respectively， while the bearing capacity increased by 34.5%. The pinch effect of the reticulated curve of strengthened columns was also improved. With the increase of axial compression ratio， the bearing capacity of specimens showed an upward trend， but both ductility and energy dissipation declined. This is because the joints strengthened can increase the bonding stress between UHPC reinforcement layer and foundation base， allowing the UHPC reinforcement layer and the core concrete forced together. In addition， Cracking of concrete and buckling of longitudinal bars can be limited by the UHPC reinforcement layer. Finally， a calculation method for flexural bearing capacity of UHPC reinforced RC square columns based on plane section assumption was proposed. The calculated results are greater than 0.85 compared with the experimental results， showing high accuracy， which verifies the reasonableness of this calculation method. The research results could provide references for engineering application and design of UHPC reinforced RC square columns with joints strengthened.

Key words:joint strengthening;UHPC strengthening;RC square columns;seismic behavior;flexural bearing capacity

CLC：TU352.11;TU375.3