Objective To study the compressive mechanical properties and constitutive models of brain tissue at different strain rates.Methods Quasi-static and medium-velocity compression tests were carried out on the white and gray matter of pig brain tissue using an electronic universal testing machine,and stress-strain curves of pig brain tissue at different strain rates were obtained.The Ogden constitutive model was used to fit the test curve,the parameters of the constitutive model were determined,and the simulation was verified using finite element software.Results The brain tissue stress-strain curves showed nonlinear characteristics,with a strong strain rate correlation and sensitivity.When tissues were compressed to 0.6 strain,the stress of white and gray matter increased by 102%and 129%,respectively,at a strain rate of 5×10-4-5×10-2 s-1,and by 50.7%and 54.6%,respectively,at a strain rate of 1-1.5 s-1.At a strain rate of 1.5 s-1,the stress in the white and gray matter increased by 347%and 413%,respectively,compared with that at 5×10-4 s-1 strain rate.The R2 value of the Ogden model was greater than 0.99,and the error between the simulation and experimental results was within 15%,thereby verifying the validity of the model.Conclusions This study is helpful for the prediction of brain tissue deformation and provides an accurate scientific theoretical basis for the establishment of scientific and reasonable human simulation targets as well as the design and improvement of brain-protective equipment.
万方数据
维普
