Establishment And Application Study On Fe Model Of Human Upper Body In Rear Impact

The rear impact on human body is always happened in rear-end collision. Under the rear impact, head is suddenly able to extend backward excessive, which is likely to cause vertebral fracture and injury in ligament. Meanwhile, the head and the back of body can hit against car seat, the strong impact force will give rise to injury such as concussion of brain, rib fracture and visceral organ fracture, which will threaten human life. People always call this injury as whiplash injury. The study, which on human biomechanics response, and the analysis, which on stress and strain of human tissue, offer the important reference for researching human protector device, which is significance on the protection of human life.For studying the response of the rear impact on human upper body, this thesis makes a finite element model of human upper body, which is based on anatomy foundation. This model is made of skull, brain tissue, cervical vertebra C1-C2, thoracic vertebra T1-T12, intervertebral disc, rib, costicartilage, sternum, clavicle, scapula, ligament and muscle. Ligament and muscle take the material of link 167 and cable, the other tissue take the material of solid 164 and linear isotropic. For calculating conveniently, this thesis adds the simplified finite element models of seat, back cushion and human waist, which are used for fixing and supporting the finite element model of human upper body. The added models all take the material of solid 164 and linear isotropic. During the rear impact, this model is set up contact on impacted place, which is used for studying human impact hurt from seat. The finished model is loaded for verifying effectiveness, and the result accord with test date.In LS-DYNA, with making the experiment of the rear impact simulation on this model, the stress and strain of model tissue are made out. After analyzing these results, there reach some important conclusions. The stress on head is large, which is caused by the seat impact. Too large stress on head will lead to concussion of brain. The stress of cervical vertebra C1-C7, thoracic vertebra T1, T12 are all also large, especially the stress on cervical vertebra C1, C2, which will lead to vertebral fracture. The strain on intervertebral disc C2-C3 is large, which will lead to herniated disk, and make people suffer the neuralgia of neck. The first and second ribs suffer the large stress. Too large stress will make the compressive deformation of thorax, which will lead to viscera injury and threaten the human life.