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加卸载响应比方法为非均匀脆性介质的灾变评估提供了新的思路,即用加载与卸载响应的差别来定量刻画介质的损伤程度。为了验证加卸载响应比方法应用于结构失效分析的有效性,首先运用加卸载响应比方法对意大利那不勒斯大学完成的1个2层楼房的加卸载实验进行分析,结果表明:在临近结构破坏之前加卸载响应比时间序列确实出现了异常明显的升高及回落;进而引入岩石破裂声发射实验进行研究,发现采用轴向应变做响应量计算得到的加卸载响应比时间序列与楼房结构的响应比曲线在演化趋势上非常一致。进一步比较声发射能量率和宏观应做为响应得到的加卸载响应比时间序列,发现两者有着较为同步的稳定、异常、升高至峰值、急剧回落的演化过程。为了明确加卸载响应比与结构内部损伤的联系,基于损伤力学方法从理论上对此进行了分析,很明显加卸载响应比值在一定程度上可以反推结构的损伤程度,其演化可以为大型结构健康评估和工程灾变分析提供有益的参考及借鉴。
The unloading response ratio method provides a new idea for the catastrophic assessment of non-uniform brittle media, that is to quantify the damage degree of the medium by using the difference between loading and unloading responses. In order to verify the effectiveness of the method of loading and unloading response ratio applied to structural failure analysis, an unloading response method was used to analyze the loading and unloading experiment of a 2-storey building completed by the University of Naples, Italy. The results show that: Unloading response time series did indeed appear unusually significant rise and fall; and then the introduction of rock burst acoustic emission experiments to study and found that the axial response of the strain response calculated than the time series and the response curve of the building structure In the evolutionary trend is very consistent. Further comparison of acoustic emission energy rates and macroscopic responses to loading and unloading response time series shows that both of them have more stable evolution, abnormality, peak-to-peak and abrupt evolution. In order to clarify the relationship between the loading-unloading response ratio and the internal damage of the structure, this method is theoretically analyzed based on the damage mechanics method. Obviously, the unloading response ratio can reverse the damage degree of the structure to a certain extent, and its evolution can be large structure Health assessment and engineering disaster analysis provide useful reference and reference.