The Simulation Of The Composite Laminates Damage Patch-bonded Repair

Now, bonded patch repair is a common method for repairing composite structures,however, until to now, there are a few numerical simulation based on continuum shell for the repaired composite structural, most of all are using 3D solid elements. But in the ABAQUS finite element software, using 3D solid elements to simulate the fail progress of composite structural is much more complicate compared with continuum shell, because we have to program the Hashin fail criteria for 3D solid elements, and it depends on a special case.Considering the difficulties, for some simple cases, we can use continuum shell to get accurate results with much less calculate time.In this context, as used herein, solid shell elements will replace the 3D solid element for the simulation of repaired composite laminates which has damage, the repair method is bonded patch repair. Then analyze the factors which affect the ultimate strength of the repairs structural, the failure modes and its expansion course will be explored too.First of all, this paper reviews the related background, and the development of numerical simulation about the bonded patch composite structural are also summarized. From point of view of the technique development of bonded patch repair of composite structural, the main types, the main steps and process, summed up the previous work about the bonding repair.Described and summarized the basic mechanics theory and damage theory, provided a theoretical basis for the subsequent numerical simulation.Secondly, listed the constitutive relation of the composite elements and adhesive elements, provided the failure criteria and damage evolution with a detailed explanation.According to the relevant experiments, compared the experimental values with the calculated values, demonstrated the validity, at the same time, based on the simulation model which has a hole damage, analyzed the influence of the viscosity coefficient to calculated values. On this basis, this paper obtained a viscosity coefficient for all simulation models in this paper.Finally, based on the proven models, developed some 3D finite element models forbonded patch structural, using compressive load, the model was verified, at the same time, the failure modes and their expansion process were explored, analyzed the influence of the patch thickness and diameter to the ultimate strength of structural, and the effects of adhesive layer thickness were also analyzed. Then, used tensile loads, analyzed the failure modes and their expansion process, and analyzed the influence of the patch thickness and diameter to the ultimate strength of structural with tensile loads. In conclusion, according to the result obtained and some related repairs principle, given the final repair conclusions.