施工缝对框架结构抗震性能影响的数值分析

Influence of construction joints on seismic behavior of RC frame structures

为研究施工缝对框架结构抗震性能的影响,利用提出的施工缝模型,基于OPENSEES平台建模进行静力非线性分析和非线性动力时程分析。通过对比整浇框架与带缝框架的顶点最大位移、层间位移角、塑性铰出现和分布规律等明确施工缝对框架结构的抗震性能的影响程度。结果表明,施工缝使框架结构的变形和层间位移角显著增大,并且使8、9度区框架结构的层间位移角分布发生改变;施工缝使柱端更易出现塑性铰,更易发生"强梁弱柱"的破坏模式;在高烈度区,施工缝的影响比较显著,如果忽略其影响,将会高估框架结构的抗震性能。

Using the proposed construction joint numerical model, static nonlinear analysis and dynamic nonlinear analysis were performed to study the influence of construction joint on the seismic behavior of reinforced concrete （RC） frame structures. Ultimate deformations, story drift angles and plastic hinges were investigated from contras- ting frames with and without construction joint. The results show that the construction joint increases the deforma- tions and story drift angles remarkably, and changes the distribution of story drift angles. Construction joint makes the plastic hinges incline to appear in the end of columns and the failure pattern of ＂strong beam and weak column＂ will emerge. In the areas with high earthquake intensity, the seismic resistance of the frame structures is overestima- ted if the effect of construction joint is not considered.