配置HRB500钢筋桥墩抗震性能分析及数值模拟

发布时间：2018-08-22 15:37

【摘要】：HRB500钢筋作为一种综合性能优良的高强热轧带肋钢筋,其抗拉强度高,在混凝土结构中推广应用HRB500级钢筋可显著减少钢筋用量,取得良好的经济效益和社会效益。因此,在桥墩中采用高强钢筋替换纵筋和箍筋,来改善桥墩在强地震作用下的抗震能力具有十分重要的理论和工程实际意义。对8根配置HRB500钢筋的混凝土桥墩的抗震性能进行拟静力试验的研究和数值模拟,对其在低周往复荷载作用下的破坏特征、承载能力及位移延性、滞回曲线、骨架曲线、刚度退化、耗能能力进行分析,研究剪跨比、钢筋强度、箍筋间距、轴压比对桥墩抗震性能的影响规律。结果表明,高强钢筋的配置可以明显改善试件的滞回性能,使试件滞回曲线更加饱满,使试件的承载能力和初始刚度显著提高,但会降低试件耗能能力。在轴压比较小的情况下,箍筋间距的减小使剪跨比较小试件的滞回曲线更加饱满,试件位移延性得到改善,但会降低试件的耗能能力,对试件的极限承载能力影响不大。减小箍筋间距对剪跨比较大试件的极限承载能力、位移延性的提高作用有限,但会使试件的耗能能力减弱。在配箍率较大,核心混凝土得到充分约束的情况下,轴压比的增大可以显著提高试件的初始刚度和极限承载能力,但会使试件位移延性明显减弱,对试件耗能能力的影响不显著。基于ANSYS有限元软件,对试验各工况进行了数值模拟及非线性分析,并通过ANSYS有限元分析结果与实测结果进行对比发现两者吻合程度较高,证明了试验结论的正确性、可靠性和模型建立的合理性。为今后ANSYS对桥墩抗震性能的模拟提供参考。
[Abstract]:As a kind of high strength hot rolled ribbed steel bar with good comprehensive properties, HRB500 steel bar has high tensile strength. The application of HRB500 grade steel bar in concrete structure can significantly reduce the amount of steel bar, and obtain good economic and social benefits. Therefore, it is of great theoretical and engineering significance to replace longitudinal reinforcement and stirrups with high strength steel bar in pier to improve the seismic capacity of pier under strong earthquake. The quasi static test and numerical simulation of the seismic behavior of 8 concrete piers with HRB500 reinforcement were carried out. The failure characteristics, load-carrying capacity and displacement ductility, hysteretic curve, skeleton curve under low cycle reciprocating load were studied. The effects of shear span ratio, reinforcement strength, stirrups spacing and axial compression ratio on seismic behavior of piers are studied. The results show that the high strength steel bars can obviously improve the hysteretic properties of the specimens, make the hysteretic curves of the specimens more full, increase the load-bearing capacity and initial stiffness of the specimens, but reduce the energy dissipation capacity of the specimens. Under the condition of small axial compression, the hysteretic curve of shear span is more full and the displacement ductility of specimen is improved, but the energy dissipation capacity of specimen will be reduced with the decrease of stirrups spacing, which has little effect on the ultimate load-bearing capacity of the specimen. Reducing the space between stirrups has a limited effect on the ultimate bearing capacity of the specimens with large shear span and the improvement of the displacement ductility is limited, but it will weaken the energy dissipation capacity of the specimens. When the hoop ratio is large and the core concrete is fully restrained, the initial stiffness and ultimate bearing capacity of the specimen can be significantly increased by increasing the axial compression ratio, but the displacement ductility of the specimen will be weakened obviously. The effect on the energy consumption capacity of the specimen is not significant. Based on ANSYS finite element software, numerical simulation and nonlinear analysis are carried out on each condition of the test. By comparing the results of ANSYS finite element analysis with the measured results, it is found that the two conclusions are in good agreement with each other, which proves the correctness of the test results. Reliability and rationality of modeling. It provides a reference for the future ANSYS simulation of pier seismic performance.
【学位授予单位】：河北工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：U442.55

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