窄锥结构的最不利动冰力

破坏模式效应是锥体结构动冰力的主导的综合效应。过渡型弯曲破坏峰值冰力最大,周期性最强,对冰速敏感,是最不利破坏模式,可产生最不利动冰力。通过1个案例、4个分析模型和1个数值模型论证了这一破坏模式效应假设。据此提出了一个窄锥动冰力函数,给出了3个参数的表达式。算例结果显示,在过渡破坏条件下预测的动冰力接近实测值。

THE WORST DYNAMIC ICE FORCE ON NARROW CONICAL STRUCTURES

The failure modal effect is a dominant synthetic effect for dynamic ice forces on conical structures. It should be the transitional failure acted as the worst failure mode,which associated the worst ice force with the biggest peak,the most repeatable period and most sensitive to velocity. This hypothesis is proved by using one case study,four analytical models and one numerical model. Based on these,a dynamic ice-load function and its 3 parameters used for narrow conical structures are formulated. A calculating example shows that under the transition conditions,the predicted dynamic ice forces are closed to the measured ones.