Interfacial Fractural Analysis For Joint-Structures With Multi-material System

The fractural analysis for the multi-material joint region in the large structures is a key factor to assess the reliability of the whole structure.The aim of this paper is to study on fracture behavior of the multi-material and multi-interfacial structures with a component of rubber.Firstly,based on the method of successive linearization by incremental load,a modified virtual crack closure technique has been proposed,in which both material and geometric nonlinearity are considered.The efficiency of the technique was proved through the comparison of numerical results between present and published literatures.Then,a SLB model with a rubber interface was established,and the energy release rate and its component under different material matches were calculated.Lastly,the fracture behavior of a typical joint-structure with metal-rubber-composite multi-material system was investigated,and the effects of the properties of component material,crack positions and structrue dimensions upon the values of total energy release rate were discussed,and according to the variation of energy release rate of multi-interfacial cracks,a corresponding fracture criterion for crack onset was proposed.(1) The modified virtual crack closure technique provided is convenient,in which both material and geometric non-linearity were considered.Through the calculations of total energy release rate and its components of crack for a rubber component,it can be found the validity and efficiency of the present technique can be guaranteed within a given extent of extension for fracture analysis of rubber components.(2) Inserting rubber layer in the laminated SLB model induce the material mismatch increased,hence the total energy release rate and the ratio of modeâ…¡component increase. With increasing crack length,both the total energy release rate and its component increase(3) The fractural analysis of a typical joint-structures with multi-material indicates the effect of the thickness of outer composite component upon the valuesof energy release rate is higher than of outer composite component.The present work should be a great value to engineering design and analysis.