Experimental Study Of The Effect Of Cone Angle On The Ice-induced Vibration Of Compliant Conical Structure

At the present time, ice-breaking cones have been used in more and more ice-resisting structures to reduce the ice force, but the actual effect of it hasn't been confirmed, which especially includes the ice-induced vibration. Some existing spot data indicates that: the breaking process of ice sheet before conical structures occurs periodically, and when the period of ice force approach the natural period of structure, the vibration of structure will be greatly enhanced, which can bring a serious influence on the security of structure and the related process of producing.From 2004 to 2005, a series of experimental study of ice-induced vibration on compliant cone was carried out in the ice engineering laboratory of TianJin university. The main work of this paper is to analyse the effect of cone angle on the ice-induced vibration on compliant cone.During the researching work, the physical and mechanical characters of ice were summarized and through the analysis of the theories of ice-induced vibration, we have got a conclusion that ice-induced vibration on compliant cone is a kind of forced vibration, and the key parameters of vibration are the breaking length of ice sheet, the velocity of ice and the amplitude of ice force;And then, this paper gives a detailed presentation of the model experiment of ice-induced vibration on compliant cone. Because of the two-time fracture of the ice sheet, the dynamic ice force has an obvious characteristic that a high and a low loading-offloading course appear by turns, and the low loading course starts before the former course offloads completely.Based on the above-mentioned characteristic, a new dynamic ice force function which can fit engineering fact more compatibly was established, and then the effect of cone angle on the ice-induced vibration on compliant cone was analysed. Finally we have educed the effecting level of cone angle on the period and amplitude of ice force, which can guidance the design of ice-breaking cone in actual ice-resisting structures.