响应面法预测单层球壳简单动荷载下的破坏形式

Failure types prediction of single-layer spherical shells under simple dynamic loads using respond surface method

单层球壳在简单动荷载作用下的破坏形式为强度破坏和动力失稳,预测一个球壳的破坏形式具有重要的研究意义。本文通过响应面法计算了中等跨度的单层球壳在简单动荷载(简谐荷载和阶跃荷载)下Pcr(极限荷载)和Pcr/2两个荷载幅值对应的可靠指标及其比值,并定义该值为破坏指标(Kβ),建立了Kβ与破坏类型的定量关系。在此基础上,分析了预测单层球壳破坏形式的原则,制定了合理有效的预测流程,最终达到了预测的目的。结果表明,本文所提出的方法具有较好的准确性和较高的效率。

Dynamic instability and strength failures were the failure types of single-layer spherical shells under simple dynamic loads. So prediction of the failure types is significant. The response surface method has been used to obtain the reliability index β1 and β2 under the ultimate load Pcr and Pcr/2 respectively. The concept of damage index Kβ is presented which equals β2/β1. The relationship generalized between Kβ and the failure types. Based on the analysis mentioned above, the principles of the failure types prediction have been discussed in detail, and at the same time, the prediction process has been presented. So the purpose to predict the failure type has been achieved. As well, the prediction method has been Proved to be accurate and effective.