【摘要】 为精确描述钢材在地震作用下强度和刚度退化规律,在考虑Bauschinger效应的K&K模型基础上,引入一种基于连续损伤力学原理的损伤模型,并定义相应的失效准则。通过与已有试验结果对比,验证了引入损伤模型和失效准则后的修正K&K模型能有效提高钢柱在地震作用下动力响应的模拟精度。考虑材料损伤累积效应,钢柱竖向承载力显著降低,柱顶处产生较大的峰值位移和残余位移。运用修正K&K模型,对空心带肋钢柱在强震作用下的损伤演化规律进行分析,结果表明,钢柱损伤在峰值加速度出现时段内发展迅速,并且随地震强度的增大而增大,钢柱的破坏模式为弯曲破坏。更多还原

【Abstract】 In order to precisely simulate the degradation of strength and stiffness of steel under earthquake action,a damage model developed using the continuum damage mechanics was introduced and the corresponding failure index was defined,based on the Krieg & Key model considering the Bauschinger effect of steel material.It was verified by comparing with previous test results that using the proposed modified K&K model the accuracy of the simulated dynamic responses of steel columns under earthquakes could be improved.With the consideration of damage accumulation,the vertical load carrying capacity of steel columns decreased drastically and the peak displacement and residual displacement at column top ends increased.Analysis on the damage evolution of a hollow stiffened steel column under severe earthquake was also conducted using the modified K&K model.The results show that the damage of the steel column develops rapidly and immediately before and after the peak acceleration is reached.And the higher the seismic intensity is,the larger the damage is.The column finally fails due to flexure.更多还原