本文選題：車輛安全 + 腹部損傷��； 參考：《天津科技大學(xué)》2012年碩士論文

【摘要】：根據(jù)國家公安部交通管路局提供的數(shù)據(jù)顯示,我國每年有1.85萬個兒童死于交通安全事故,而去年德國在車內(nèi)死亡的兒童僅76人。我國兒童在交通事故中的死亡率是美國的2.6倍,歐洲的2.5倍,己成為14歲以下兒童的第一死因,故有必要研究兒童胸腹部在碰撞中的損傷機(jī)理。在交通事故中,兒童乘員在約束系統(tǒng)的約束下,4歲以上兒童乘員腹部是繼頭部之后最易受傷的部位,這主要是因為4歲以上兒童在乘車時,使用成人使用的車輛安全帶的比例較大,可是兒童的髂骨上前骨棘不發(fā)達(dá),不能使腰帶準(zhǔn)確定位,在受到碰撞沖擊時,腰帶易從髖部滑向腹部而壓迫腹部,導(dǎo)致腹部的內(nèi)臟器官由于受壓而受傷。因受到倫理學(xué)等社會因素的影響,兒童尸體實驗數(shù)據(jù)極少,國際上主要采用有限元碰撞仿真實驗研究碰撞過程中兒童的碰撞響應(yīng)。而具有實際解剖學(xué)結(jié)構(gòu)的高生物仿真度的有限元模型是碰撞仿真實驗的基礎(chǔ)。鑒于此,本研究構(gòu)建高生物仿真度的兒童有限元模型,用于研究6歲兒童腹部損傷機(jī)理極有重要意義。 本研究以6歲兒童腹部真實解剖學(xué)CT掃描圖片為基礎(chǔ),應(yīng)用Mimics軟件提取腹部幾何特征參數(shù),并且運(yùn)用逆向工程軟件Geomagic對初步幾何模型進(jìn)行處理、劃分曲面片,生成兒童腹部的幾何模型。借助TrueGrid和HyperMesh軟件對幾何模型進(jìn)行網(wǎng)格劃分和網(wǎng)格優(yōu)化,構(gòu)建完整的腹部模型。該模型包括骨骼,肌肉,韌帶等。骨骼包括腰椎(L1-L5),椎間盤。肌肉包括腹橫肌、腹內(nèi)斜肌、腹外斜肌、腹橫肌、豎脊肌、腰大肌、腰方肌,膈肌。器官包括肝臟,腎臟,胃,脾。模型中的韌帶、膈肌、腹直肌、胃采等用殼單元來模擬,其余組織均采用8節(jié)點(diǎn)6面體實體單元模擬。整個腹部模型共有165609個單元,196185個節(jié)點(diǎn)。模型采用彈性材料,彈塑性材料和粘彈性材料來模擬不同組織的性能。模型中的各個組織之間的連接是通過共同節(jié)點(diǎn)法和定義接觸實現(xiàn)的。 應(yīng)用有限元分析軟件LS-DYNA對模型做碰撞仿真實驗。實驗包括腰椎L4-L5段關(guān)節(jié)面載荷傳遞實驗和腹部側(cè)碰實驗。仿真結(jié)果與尸體實驗結(jié)果趨勢較為一致,證明該研究所構(gòu)建的6歲兒童腹部模型的有效性和可靠性。在腰椎L4-L5段的關(guān)節(jié)面載荷傳遞實驗中,發(fā)現(xiàn)兒童的實驗結(jié)果與成人有限元模型和尸體實驗結(jié)果有些差別,兒童在L4-L5的關(guān)節(jié)面處的傳遞載荷要小于成人。此實驗結(jié)果說明在外載荷作用下,兒童腰痛發(fā)生的概率要比成人小。 綜上所述,本研究所構(gòu)建的6歲兒童腹部有限元模型為開展兒童腹部損傷機(jī)理的研究提供了可靠的理論依據(jù),為推動我國兒童汽車安全法規(guī)的發(fā)展奠定了基礎(chǔ)。
[Abstract]:According to data provided by the Traffic Management Bureau of the Ministry of Public Security, 18500 children die in traffic safety accidents every year in China, compared with 76 children killed in cars in Germany last year. The mortality rate of children in traffic accidents in China is 2.6 times that in the United States and 2.5 times in Europe. It has become the first cause of death of children under 14 years of age. Therefore, it is necessary to study the injury mechanism of children's chest and abdomen in collision. In traffic accidents, the abdomen of a child over 4 years of age is the most vulnerable area after the head, mainly because children over the age of 4 are travelling by car. The proportion of vehicle seat belts used by adults is high, but the iliac spine of children is underdeveloped and cannot accurately locate the belt. When it is hit by a collision, the belt is prone to slide from the hip to the abdomen and oppress the abdomen. The visceral organs of the abdomen are injured by compression. Due to the influence of social factors such as ethics, there are very few experimental data on children's cadavers. In the world, finite element collision simulation experiments are mainly used to study the collision response of children in the process of collision. The finite element model with actual anatomical structure is the foundation of collision simulation experiment. In view of this, it is of great significance to construct a high biosimulation finite element model for studying the mechanism of abdominal injury in children aged 6 years. Based on the CT scanning images of the true anatomy of abdomen in children aged 6 years, the geometric parameters of abdomen were extracted by Mimics software, and the initial geometric model was processed by reverse engineering software Geomagic. Generate a geometric model of the child's abdomen. A complete abdominal model is constructed by using TrueGrid and HyperMesh software to mesh and optimize the geometric model. The model includes bones, muscles, ligaments and so on. Bones include the lumbar vertebrae L 1-L 5 suture, intervertebral disc. Muscles include abdominal transverse muscle, internal oblique muscle, external oblique muscle, transverse muscle, erector muscle, psoas major muscle, psoas quadrate muscle, diaphragm muscle. Organs include liver, kidney, stomach and spleen. The ligament, diaphragm, rectus abdominis and stomach were simulated by shell unit, and the other tissues were simulated by 8-node 6-hedron solid unit. The whole abdominal model has 165,609 units and 196185 nodes. Elastic materials, elastoplastic materials and viscoelastic materials are used to simulate the properties of different microstructures. The connection between the organizations in the model is realized by common node method and definition contact. The finite element analysis software LS-DYNA is used to simulate the model. The experiment includes the load transfer experiment of lumbar L4-L5 joint surface and the abdominal side impact experiment. The simulation results are consistent with the results of cadaveric experiments, which proves the validity and reliability of the abdominal model of 6 years old children. In the load transfer experiment of L4-L5 segment of lumbar vertebrae, it was found that the experimental results of children were different from those of adult finite element model and cadaveric test, and the transfer load of children at the articular surface of L4-L5 was smaller than that of adults. The results show that the incidence of low back pain in children is lower than that in adults. To sum up, the abdominal finite element model of 6-year-old children constructed in this paper provides a reliable theoretical basis for the study of the mechanism of abdominal injury in children, and lays a foundation for the development of car safety regulations for children in China.
【學(xué)位授予單位】：天津科技大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2012
【分類號】：R726.5

【參考文獻(xiàn)】

相關(guān)期刊論文 前3條

1 袁野,靳安民,何麗英,朱贊凌;利用CT掃描及CAD技術(shù)建立腰椎活動節(jié)段的有限元模型[J];中國臨床解剖學(xué)雜志;2002年04期

2 姜志國,孟如松,趙宇,周付根,董海軍;組織切片圖像的可視化技術(shù)及應(yīng)用[J];中國體視學(xué)與圖像分析;2002年03期

3 黃啟今,劉國權(quán),馬遠(yuǎn)征,薛海濱,高瑾;基于CT圖像重建腰椎活動節(jié)段三維有限元模型及其應(yīng)用[J];中國體視學(xué)與圖像分析;2004年02期

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