冰载荷下冰速与冰厚对平台动力响应的影响

Effect of Ice Velocity and Thickness on Dynamic Response of Platform under Ice Load

通过对比分析3种冰激振动理论,采用ANSYS模拟分析建立了平台模型并加载载荷参数,得出模拟分析数据。根据得到的数据发现当冰速在一定范围内时,冰与结构发生稳态振动,此时海冰对平台产生的破坏最大。冰速越远离这个范围,海冰对平台动力响应的影响越小。当冰厚不断增加时,平台的位移响应会不断增加,海冰对平台的破坏性也逐渐增大。据此可以看出冰速和冰厚都会改变冰排对结构相互作用系数,但冰厚对静冰力大小的影响远大于冰速。通过模拟分析得到的数据找到了冰激振动下平台的危险点,支持了自激振动理论。

Through comparing and analyzing three kinds of ice-induced vibration theories, having ANSYS simulation analysis used to build platform model and to load parameters was implemented. The simulation data obtained show that, when the ice velocity stays at a certain range, the ice and the structure would be in a steady-state vibration, and the sea ice would damage the platform seriously, both The ice velocity far from this range affects less the dynamic response of platform; when the ice thickness increases, the displacement response of the platform would increase continuously, and the damage of sea ice to the platform increases, too. Accordingly, both the ice speed ice thickness would change the interaction coefficient between ice and structure and the ice thickness＇ effect on the static ice force becomes much larger than that of the ice velocity. The data obtained from the simulation analysis show the dangerous point of the platform under ice-induced vibration and this supports the theory of self-excited vibration.