Study on elastic-plastic damage numerical model of epoxy resin under different loads
GUO Qiaorong
LÜ Weihang
XU Jianxin
LIU Yuanhai
Abstract：[Objective]To accurately describe the nonlinear damage evolution behavior of epoxy resin under various loading conditions,an improved Lemaitre damage model incorporating the influence of elastoplastic strain energy on damage was used,,aiming to enhance the prediction accuracy of mechanical responses of epoxy resin structures under long-term service environments.[Methods]Firstly,uniaxial tensile,compressive,and shear tests,along with corresponding loading-unloading cyclic tests,were conducted on YH69 epoxy resin specimens,and the damage parameters of the model were determined based on the elastic modulus variation method.Secondly,a UMAT user-defined material subroutine based on the improved Lemaitre constitutive model was developed on the Abaqus software platform.Then,numerical simulations of damage evolution in epoxy resin were performed under different loading conditions.Finally,the predicted results of the improved model were compared with those of the traditional Lemaitre model and the experimental data.[Results]The results indicate that the improved Lemaitre damage model can effectively characterize the entire damage evolution process of epoxy resin under tensile,compressive,and shear loads,and its predicted stress-strain curves and force-displacement curves show higher fitting accuracy and better agreement with experimental data compared with the traditional Lemaitre model.The critical damage values for tension,compression,and shear are determined as 0.28,0.25,and 0.27,respectively,with corresponding critical damage strain energy release rates of 3.4,6.7,and 3.1.
Keywords：Epoxy resinImproved Lemaitre damage modelDamage evolutionUMAT subroutineLoading and unload-ing test
Publication Date：2026-08-15
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：10( 157-166 )