Session: 07-05-01 Ice Load modelling

Paper Number: 133192

133192 - Probabilistic Analysis of Ice Load Occurrence in Floe Ice Fields 

Ships navigating in the Arctic and Antarctic regions frequently encounter the threat of ice. Floe ice exhibits various shapes and sizes, with significant variations in thickness and concentration across different ice fields. Estimating the number of ship-ice contact events accurately is crucial for strategic navigation and fatigue damage assessment.

This paper focuses on the contact occurrence in floe ice fields which can be determined by the time intervals between contacts. The occurrence in level ice fields follows a Poisson distribution and the time intervals follow an exponential distribution which has been demonstrated in numerous studies. Based on the measurement data on Polar Supply and Research Vessel (PSRV) S.A. Agulhas II during 2018/19 Antarctic voyage which encountered extensive floe ice, this paper examines the applicability of previously proposed patterns in level ice fields to floe ice fields. A mixture exponential distribution model is proposed to fit the time intervals in floe ice fields and the model is tested by two statistical methods indicating a good fit. The relationship between ice condition and distribution function is also discussed. This paper then provides a procedure to obtain the contact occurrence by Monte Carlo method based on the distribution of time intervals. To further investigate the influence of contact occurrence on short term extreme distributions of local ice loads, three methods are employed and the extreme distributions obtained from three methods are found to be highly consistent.

Presenting Author: Chenxi Xie Shanghai Jiao Tong University, School of Naval Architecture, Ocean & Civil Engineering

Presenting Author Biography: Chenxi Xie
Shanghai Jiao Tong University
Research direction: Statistical analysis of ice loads and fatigue damage assessment
Contact infomation: chenxi_xie@sjtu.edu.cn

Authors:

Chenxi Xie Shanghai Jiao Tong University, School of Naval Architecture, Ocean & Civil Engineering
Lijuan Xia Shanghai Jiao Tong University, School of Naval Architecture, Ocean & Civil Engineering
Fang Li Shanghai Jiao Tong University, School of Naval Architecture, Ocean & Civil Engineering