中文摘要：

为进一步探讨材料本构行为对构件及结构受力性能的影响,首先,进行了LYP100低屈服点钢材的本构关系试验研究,分析此材料的单调性能、滞回性能、耗能能力及循环本构模型等。在此基础上,全面对比LYP100和LYP160低屈服点钢材、普通钢材（Q345B）及高强度钢材（Q460D）的本构关系。最后,通过对比不同钢材的循环本构模型以及理想弹塑性模型对结构构件滞回行为的预测结果,深入研究材料本构关系对构件及结构的重要影响。结果表明：低屈服点钢材单调以及循环强屈比均在2.0~3.0以上,是普通钢材以及高强度钢材的2.0倍~3.0倍。同时,低屈服点钢材具有更好的延性和耗能能力。由于低屈服点钢材具有显著的各向同性强化行为,其采用循环本构模型和理想弹塑性模型的计算结果差异更大。因此,在结构计算分析中,需要根据所采用的钢材选取适当的本构关系模型。

英文摘要：

In order to investigate the effect of constitutive behaviors on mechanical performance of members and structures, the constitutive relationship tests of LYP100 low yield point steel were carried out firstly. The monotonic behavior, ductility, hysteretic behavior, energy-dissipation capacity and cyclic constitutive model were analyzed. Based on these results, the constitutive relationship of low yield point steel, normal strength steel （Q345B） and high strength steel （Q460D） were fully compared. Finally, the predicted hysteretic behaviors of different steels with both cyclic constitutive model and ideal elastic-plastic model were compared to further discuss the significant effect of constitutive relationship on members and structures. The results show that the monotonic and cyclic tensile-to-yield ratios of low yield point steels are more than 2.0-3.0, 2.0-3.0 times of normal strength steel and high strength steel. Meanwhile, low yield point steels have better ductility and energy dissipation capacity. Because low yield point steels have obvious isotropic behaviors, significant difference is observed between the calculated results using cyclic constitutive model and ideal elastic plastic model. Therefore, for structural analysis, an appropriate constitutive relationship should be adopted according to different steels.