超高性能混凝土柱的抗震性能分析

Seismic Performance Analysis of Ultra-high Performance Concrete Compression Members

为分析超高性能混凝土(Ultra-High Performance Concrete,UHPC)柱的抗震性能,采用有限元程序OpenSees建立了UHPC柱的分析模型,以试验结果验证了分析模型的适用性。基于被验证的有限元模型,分析了轴压比、纵筋配筋率和UHPC强度对UHPC柱受力变形性能的影响。结果表明:柱的极限承载能力随柱轴压比、纵筋配筋率和UHPC强度的增大而增大;延性系数随柱轴压比、UHPC强度的增大而减小,随纵筋配筋率的增大而增大。就所分析的情形而言,轴压比从0.1提高到0.4,极限承载能力增大75%,延性系数减小66%;纵筋配筋率从1.54%增大到2.54%,极限承载能力增大28%,延性系数增大5%;UHPC强度等级从UC120增大到UC180,极限承载能力增大21%,延性系数减小17%。若以位移延性系数不小于3为目标,则UHPC柱的设计轴压比限值可取为0.8。

In order to analyze the seismic performance of ultra-high performance concrete(UHPC)columns,OpenSees was used to establish the analytical model of UHPC column.The applicability of the analysis model is verified by the test results.Based on the verified model,the effects of axial load ratio,reinforcement ratio and UHPC strength on the mechanical and deformation performance of UHPC columns are analyzed.The results show that the ultimate carrying capacity of the column increases with the increase of axial load ratio,reinforcement ratio and UHPC strength;the ductility coefficient decreases with the increase of axial load ratio and UHPC strength,and increases with the increase of reinforcement ratio.For the case analyzed,when the axial load ratio increases from 0.1 to 0.4,the ultimate carrying capacity increases by 75%,and the ductility coefficient decreases by 66%;when the reinforcement ratio of increases from 1.54%to 2.54%,the ultimate carrying capacity increases by 28%,and the ductility coefficient increases by 5%;when the strength grade of UHPC increases from UC120 to UC180,the ultimate carrying capacity increases by 21%,and the ductility coefficient decreases by 17%.If the displacement ductility coefficient is not less than 3,the limit value of axial load ratio is 0.8 for UHPC columns.