基于损伤等效的直立锁边屋面板动态抗风揭试验方法

Test method of dynamic wind uplift for standing seam roof plate based on damage equivalence

围护结构在台风等极端风下的抗风性能需要依靠动态试验测定,试验周期长导致成本高且模拟研究受限。基于直立锁边屋面板材料的损伤本构模型,通过疲劳分析研究荷载幅值对材料损伤影响,提出简化荷载序列组合。借助雨流计数法统计测点风压时程得到基于损伤等效的简化荷载循环,提出动态抗风揭试验方法。参照不同试验方法开展抗风揭试验,通过对比发现,试验方法对屋面板风揭破坏过程影响不明显。除永久塑性变形外,该文试验方法与现有试验方法下屋面板损坏现象基本一致,屋面板均为撕裂破坏。不同试验方法下屋面板承载力差异在10%~20%间。该文试验方法加载周期小于1h,现有试验方法加载周期则大于20h。在屋面板风揭破坏过程、承载力等抗风揭性能差异不大情况下,该文试验方法可大幅降低试验周期,为开展模拟研究奠定基础。

The wind-resistant performance of cladding under extreme wind such as typhoon is usually evaluated by the dynamic wind uplift test,whose period is usually long and may result in high test cost and limited simulation.Based on the damage constitutive model of roof plate material,the effect of load amplitude on material damage is studied through fatigue analysis,and a simplified load sequence combination is proposed.Combined with rain flow counting method,a simplified load cycle based on damage equivalence is obtained,and a dynamic wind uplift test method is proposed.By comparing different test methods for the wind-resistant test,it is found that the test method has no obvious effect on the wind uplift failure process of roof plates.Except for the permanent plastic deformation,the damage of the roof plate under the test method is basically the same as that under the ex-isting test method,and the roof plates all occur tearing failure.Under different test methods,the error of bearing capacity of roof plates is between 10%and 20%.The loading cycle of the proposed test method is less than lh,while that of the existing test methods is usually more than 20h.Under the condition that there is little difference in wind uplift failure process and bearing capacity,the test method proposed in this paper can greatly reduce the test cycle and lay a foundation for simulation research.