无粘结预应力混凝土梁抗震性能分析
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摘要
预应力结构具有跨度大、抗裂性能好的优点,可使建筑内部布置更加灵活,带来更加舒适的居住环境,同时便于内部结构的调整,使设计方案更加多元化。通过3根无粘结PC梁和1根RC梁的拟静力试验,对比分析PC梁与RC梁抗震性能的差异,研究所施加预应力、配筋率对无粘结PC梁抗震性能的影响。试验结果表明,纵向配筋率相同时,所施加的预应力越小,滞回曲线越饱满,但其极限承载力和延性没有明显提高;纵筋的配筋率的提高,可提高PC梁的承载力,但会降低其延性;与PC梁相比,RC梁耗能能力更好,但破坏时裂缝宽度较宽,延性比PC梁低。
With the advantages of large span and good anti-cracking property, the prestressed structure can make the internal space of the building more spacious and bring more comfortable living environment. At the same time, it is more convenient to adjust the internal structure and diversify the design scheme. Through the quasi-static tests on 3 unbonded PC beams and 1 RC beam, the seismic performance differences between PC beam and RC beam were compared and the influence of prestressed reinforcement and ordinary reinforcement ratio on the seismic performance of unbonded PC beam were analyzed. The results of the experiment indicate that, with the same longitudinal reinforcement ratio, the smaller the prestress is, the fuller the hysteretic curve is. However, the ultimate bearing capacity and ductility are not improved obviously. By increasing the longitudinal reinforcement ratio, it can improve the bearing capacity of PC beam, but reduce its ductility. Compared with PC beam, RC beam has better energy dissipation ability, but wider crack width and lower ductility.
With the advantages of large span and good anti-cracking property, the prestressed structure can make the internal space of the building more spacious and bring more comfortable living environment. At the same time, it is more convenient to adjust the internal structure and diversify the design scheme. Through the quasi-static tests on 3 unbonded PC beams and 1 RC beam, the seismic performance differences between PC beam and RC beam were compared and the influence of prestressed reinforcement and ordinary reinforcement ratio on the seismic performance of unbonded PC beam were analyzed. The results of the experiment indicate that, with the same longitudinal reinforcement ratio, the smaller the prestress is, the fuller the hysteretic curve is. However, the ultimate bearing capacity and ductility are not improved obviously. By increasing the longitudinal reinforcement ratio, it can improve the bearing capacity of PC beam, but reduce its ductility. Compared with PC beam, RC beam has better energy dissipation ability, but wider crack width and lower ductility.
引文
[1]蔡跃,熊学玉,黄鼎业.预应力混凝土框架结构的快捷设计方法[J].结构工程师,2002(4):1-4.
[2]LIN T Y,BURNS N H.Design of prestressed concrete structures[M].New York:Wiley,1981:1-24.
[3]NAWY E G.Prestressed concrete:a fundamental approach[M].Upper Saddle River:Prentice Hall,1996:1-36.
[4]PRIESTLEY M N,TAO J R.Seismic response of precast prestressed concrete frames with partially debonded tendons[J].PCI Journal,1993,38(1):58-69.
[2]LIN T Y,BURNS N H.Design of prestressed concrete structures[M].New York:Wiley,1981:1-24.
[3]NAWY E G.Prestressed concrete:a fundamental approach[M].Upper Saddle River:Prentice Hall,1996:1-36.
[4]PRIESTLEY M N,TAO J R.Seismic response of precast prestressed concrete frames with partially debonded tendons[J].PCI Journal,1993,38(1):58-69.