Research On Damage Assessment And Repair Of Composite Laminate

Composite laminate has been widely used because of its unique advantages. But it also bringssome new problems, such as composite laminate damage. In this paper，by the Patran/Nastransoftware and PCL, the strength of laminate containing a hole is analysed, and the damage evaluationis given. The scarf repair method is chosen to repair the damage laminate. The load carrying capacityof repair laminate is analysed，and compared with experimental results.Through Parametric modeling module of Patran software and PCL，the.ses file is compiled，thenthe parametric damage models，the progressive damage models and the stiffness degradation modelsare created. Hashin failure criteria of three dimension and stiffness degradation method of tan’s areused to analysis progressive failure of damage models. In order to find the relationship betweendamage size and residual strength, the damage models are divided into three groups: the through-holedamage models which has same width ‘w’ and different diameter ‘d’; the damage models which hassame ‘w’，different ‘d’ and different depth of damage ‘h’; the damage models which has same ‘d/w’and different ‘d’. Through the calculation and analysis of residual strength of each group，the damagecan be evaluated. The scarf repaire method is chosen to repair damage area, and the angle of repair isbetween4°~6°. Two different methods are used to creat the finite element models. By thecalculation precision and time, the appropriate modeling method can be found.The results of finite element analysis coincided with experimental data very well with theacceptable error. Through the relationship between damage size and residual strength, more strengthof damage structures can be predicted.