Distinct Element Simulation of Ice-Structure Interactions

摘要

Appropriate estimation of ice-structure interaction is of great importance in the design of offshore structures in ice-infested regions. The present paper deals with numerical simulations of three-dimensional ice-structure models done under the research project ,"Study on Ice Loads acting on Marine Structures", planned by Japan Ocean Industries Association (JOIA) and funded by the Ministry of International Trade and Industry. In order to trace ice-feilure process against a structure successively, distinct element methods(DEM) have been adapted, taking advantage oftheir tractability to non-continuous media over standard finite element methods, and PFC (Particle Flow Code) -3D by developed ITASCA, have been investigated. In applying PFC-3D to floating ice-structure interaction modeling, model has been newly added to the original one, the buoyant-spring model to take the variation of buoyancy into consideration. Then, some numerical results, including preliminary simulations ofice ride-up on upward and downward breaking conical structure model, are presented. In addition, modified PFC has been tested and examined its applicability to the simulation of failure mode ofice sheet caused by structures and the estimation of ice load against them, comparing with the results of ice tank test. The conclusion ofthis study is that the present distinct element code has promise as powerful working tools for ice-structure interaction investigations such as prediction of ice sheet ride-up or push-down to and ice load against sloping structures.