The Research Of Injury Mechanism Of Occupant Lumbar Spine In Frontal Impact

The vehicle collision accident statistics show that the frequency of the lumbar fracture of the occupant in the frontal impact is on the rise in recent years.But the current evaluation criteria for the injury of the lumbar spine in the automobile collision experiment are not perfect.It is urgent to predict the degree of the lumbar injury in the frontal impact and to put forward its evaluation standard.In order to explore the mechanism of the lumbar injury of the occupant in the frontal impact,this study has improved the lumbar of the GHBMC human model,and established a finite element model of the human lumbar that is in accordance with the biomechanical characteristics.The effects of different impact velocity,impact direction,contact friction coefficient and contact stiffness on the sensitivity of lumbar spinal injury were analyzed with the improved lumbar model.On this basis,this study has reduced the improved lumbar model to the human model,and a complete frontal impact simulation was carried out to explore the mechanism of lumbar fracture in the frontal impact.The results showed that the impact velocity was the most significant factor for lumbar injury,and the greater the impact velocity,the greater the risk of lumbar injury.The effect of contact stiffness on lumbar spine injury is also significant.The greater the contact stiffness,the greater the risk of lumbar injury.However,the impact of impact angle and contact friction coefficient on lumbar injury has not reached significant standard,but there is a certain trend:the greater the impact angle,the lower the risk of lumbar injury;the greater the contact friction coefficient,the greater the risk of lumbar injury.In a frontal collision,the upper body bent forward,causing pressure on the lumbar spine.And the pressure between seat and human body results in the extrusion of the lumbar spine.Under the joint action of both,the lumbar spine bears a large axial load,so it is prone to fracture.This subject has completed the finite element modeling of the lumbar with high biomechanical characteristics.The sensitivity of the lumbar injury factors is analyzed,and the mechanism of the lumbar injury in the frontal collision is systematically studied.