Name: a coupled experiment-finite element modeling methodology for assessing high strain rate mechanical response of soft biomaterials
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The authors would like to recognize the Center for Advanced Vehicular Systems (CAVS) and the Agricultural and Biological Engineering Department at Mississippi State University for supporting this work. This material is based upon work supported by the U.S. Army TACOM Life Cycle Command under Contract No. W56HZV-08-C-0236, through a subcontract with Mississippi State University, and was performed for the Simulation Based Reliability and Safety (SimBRS) research program. Also, this material is based upon work supported by the National Nuclear Security Administration, (Department of Energy) under award number [DE-FC26-06NT42755]. Finally, the authors would like to thank Mr. David Adams, Mr. Michael McCollum and Ms. Erin Colebeck for their effort in this research.

注：伦理学声明：目前的工作是唯一的机构的研究政策，严格遵循合规性（ORC）的指导方针合适的生物安全和Office。 1.生物材料样品采购<ol><li>穿戴个人防护装备按照实验室和/或机构的标准生物安全协议。穿封闭趾鞋，裤长，白大褂，手术手套，防护面罩和护目镜，同时处理猪组织和测试。 </li><li>获得健康猪的猪组织（头部，腹部，或后腿）从内1-2小时验尸当地的屠宰场?...

<ol>
	<li>Champion, H. R., Holcomb, J. B., Young, L. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Injuries+from+explosions:+physics,+biophysics,+pathology,+and+required+research+focus.">Injuries from explosions: physics, biophysics, pathology, and required research focus.</a> J Trauma. 66 (5), 1468-1477 (2009).</li><li>Aubry, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Summary+and+agreement+statement+of+the+First+International+Conference+on+Concussion+in+Sport,+Vienna+2001.+Recommendations+for+the+improvement+of+safety+and+health+of+athletes+who+may+suffer+concussive+injuries.">Summary and agreement statement of the First International Conference on Concussion in Sport, Vienna 2001. Recommendations for the improvement of safety and health of athletes who may suffer concussive injuries.</a> Br J Sports Med. 36 (1), 6-10 (2002).</li><li>Born, C. T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blast+trauma:+the+fourth+weapon+of+mass+destruction.">Blast trauma: the fourth weapon of mass destruction.</a> Scand J Surg. 94 (4), 279-285 (2005).</li><li>Cullis, I. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blast+waves+and+how+they+interact+with+structures.">Blast waves and how they interact with structures.</a> J R Army Med Corps. 147, 16-26 (2001).</li><li>Ngo, T., Mendis, P., Gupta, A., Ramsay, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Blast+Loading+and+Blast+Effects+on+Structures&#8211;An+Overview.">Blast Loading and Blast Effects on Structures&#8211;An Overview.</a> Electronic Journal of Structural Engineering. 7, 76-91 (2007).</li><li>Usmani, Z., Alghamdi, F., Kirk, D., Usmani, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Intelligent+Agents+in+Extreme+Conditions+&#8211;+Modeling+and+Simulation+of+Suicide+Bombing+for+Risk+Assessment.">Intelligent Agents in Extreme Conditions &#8211; Modeling and Simulation of Suicide Bombing for Risk Assessment.</a> Web Intelligence and Intelligent Agents. , (2010).</li><li>Guskiewicz, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Cumulative+effects+associated+with+recurrent+concussion+in+collegiate+football+players+the+NCAA+Concussion+Study.">Cumulative effects associated with recurrent concussion in collegiate football players the NCAA Concussion Study.</a> JAMA. 290 (19), 2549-2555 (2003).</li><li>Finkelstein, E., Corso, P., Miller, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> The Incidence and Economic Burden of Injuries in the United States. , (2006).</li><li>Prabhu, R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Coupled+experiment/finite+element+analysis+on+the+mechanical+response+of+porcine+brain+under+high+strain+rates.">Coupled experiment/finite element analysis on the mechanical response of porcine brain under high strain rates.</a> JMech Behav Biomed Mater. 4 (7), 1067-1080 (2011).</li><li>Horstemeyer, M. F. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Integrated Computational Materials Engineering (ICME): Using Multiscale Modeling to Invigorate Engineering Design with Science. , (2012).</li><li>Bouvard, J. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+general+inelastic+internal+state+variable+model+for+amorphous+glassy+polymers.">A general inelastic internal state variable model for amorphous glassy polymers.</a> Acta Mechanica. 213, 1-2 (2010).</li><li>Kenner, V. H., Goldsmith, W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impact+on+a+simple+physical+model+of+the+head.">Impact on a simple physical model of the head.</a> J Biomech. 6 (1), 1-11 (1973).</li><li>Khalil, T. B., Viano, D. C., Smith, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Experimental+analysis+of+the+vibrational+characteristics+of+the+human+skull.">Experimental analysis of the vibrational characteristics of the human skull.</a> J. Sound Vib. 63 (3), 351-376 (1979).</li><li>Pervin, F., Chen, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+mechanical+response+of+bovine+gray+matter+and+white+matter+brain+tissues+under+compression.">Dynamic mechanical response of bovine gray matter and white matter brain tissues under compression.</a> J Biomech. 42 (6), 731-735 (2009).</li><li>Prevost, T. P., Balakrishnan, A., Suresh, S., Socrate, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biomechnics+of+brain+tissue.">Biomechnics of brain tissue.</a> Acta Biomater. 7 (1), 83-95 (2011).</li><li>Saraf, H., Ramesh, K. T., Lennon, A. M., Merkle, A. C., Roberts, J. C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mechanical+properties+of+soft+human+tissues+under+dynamic+loading.J.">Mechanical properties of soft human tissues under dynamic loading.J.</a> J Biomech. 40 (9), 1960-1967 (2007).</li><li>Van Sligtenhorst, C., Cronin, D. S., Wayne Brodland, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High+strain+rate+compressive+properties+of+bovine+muscle+tissue+determined+using+a+split+Hopkinson+bar+apparatus.">High strain rate compressive properties of bovine muscle tissue determined using a split Hopkinson bar apparatus.</a> J Biomech. 39 (10), 1852-1858 (2006).</li><li>Song, B., Chen, W., Ge, Y., Weerasooriya, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Dynamic+and+quasi-static+compressive+response+of+porcine+muscle.">Dynamic and quasi-static compressive response of porcine muscle.</a> J Biomech. 40 (13), 2999-3005 (2007).</li><li>. MSU JHBT Data Processing and MSU High Rate Software Manual Available from: <a target="_blank" href="https://icme.hpc.msstate.edu/mediawiki/index.php/File:MSU_JHBT_Data_Processing_and_MSU_High_Rate_Software_Manual.zip">https://icme.hpc.msstate.edu/mediawiki/index.php/File:MSU_JHBT_Data_Processing_and_MSU_High_Rate_Software_Manual.zip</a> (2014)</li><li>Zhao, H., Gary, G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+use+of+SHPB+techniques+to+determine+the+dynamic+behavior+of+materials+in+the+range+of+small+strains.">On the use of SHPB techniques to determine the dynamic behavior of materials in the range of small strains.</a> Int J Solids Struct. 33 (23), 3363-3375 (1996).</li><li>Zhao, H., Gary, G., Klepaczko, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=On+the+use+of+a+viscoelastic+split+hopkinson+pressure+bar.">On the use of a viscoelastic split hopkinson pressure bar.</a> Int J Impact Eng. 19 (4), 319-330 (1997).</li><li>. MSU TP Ver 1.1. Available from: <a target="_blank" href="https://icme.hpc.msstate.edu/mediawiki/index.php/File:MSU_TP_Ver_1.1.zip">https://icme.hpc.msstate.edu/mediawiki/index.php/File:MSU_TP_Ver_1.1.zip</a> (2014)</li><li>Gray, G. T., Blumenthal, W. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> ASM Handbook, Mechanical Testing and Evaluation. 8, 488-496 (2000).</li><li>Dharan, C. K. H., Hauser, F. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+stress-strain+characteristics+at+very+high+strain+rates.">Determination of stress-strain characteristics at very high strain rates.</a> Exp. Mech. 10 (9), 370-376 (1970).</li><li>Chen, J., Priddy, L. B., Prabhu, R., Marin, E. B., Horstemeyer, M. F., Williams, L. N., Liao, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Traumatic+Injury:+Mechanical+Response+of+Porcine+Liver+Tissue+under+High+Strain+Rate+Compression+Testing.">Traumatic Injury: Mechanical Response of Porcine Liver Tissue under High Strain Rate Compression Testing.</a> Proceedings of the ASME 2009 Summer Bioengineering Conference (SBC2009). , (2009).</li></ol>

所报告的方法，它耦合SHPB实验和SHPB的有限元建模提供了一种新的和独特的技术来评估生物材料在高应变率单轴真应力 - 应变响应。为了促使机械性质固有的天然组织，必须小心SHPB测试之前保持之间5.56-7.22℃下的生物材料样品。如果试样被冷却到低于5.56℃，存在于组织中水开始crystalize入冰水，随后改变了组织的机械性能。虽然其他研究人员15-18冻结样品从机械降解保鲜的目的，结果从SHPB...

动机 耦合分离的基本目标-霍普金森压杆（SHPB）实验/软生物材料（如脑，肝，肌腱，脂肪等 ），有限元建模是提取其单轴机械行为对人体FE进一步实施有害的机械载荷下的模拟。人体的有限元（FE）的模型包括一个详细人体模型和历史依赖性多尺度粘弹性粘塑性内部状态变量（ISV）材料对各种人体器官模型。这种人体模型可以用于框架搭建伤害保障更好的标准，以设计新颖护具，并且使乘员为中心的车辆设计。 两种模式率高伤害已被广泛观测到人类的创伤：爆炸冲击波和钝物撞击。爆炸性武器爆炸伤害traumati的主要来源Ç损伤（TI）和死亡的战场上1的首要原因。当引爆，炸药这些形成产生大的和突然的加速和变形向外传播的冲击波。由此产生的载荷会对那些暴露的严重威胁。虽然任何部分的解剖结构可通过冲击波受伤，关注的主要区域是：（1）下肢由于其靠近地面，和（2）的头部自伤能抑制正常的脑功能和存活2 3。这些损伤可以分为取决于损伤的持续的类型的伯，仲，或叔受伤。因为爆炸的强度的特征在于它的重量或尺寸，间隔距离，正脉冲的持续时间，并通过它传播介质，它可以是难以充分归类这些伤害3-6。国会报告指出，军事人员因遭遇爆炸近179,000外伤武器装备和车辆碰撞在伊拉克和阿富汗从2000年至2010年3月2日，由于自然和现代作战位置，头部受伤是军事和平民3领先的担忧。 除了作战场景，TI有多种原因，包括汽车的创伤;圈地，摩托车和家庭事故;和运动损伤。例如，尽管改进安全设备和协议，机械引起创伤性脑损伤（TBI）仍然是死亡率和发病率终身在美国疾病控制中心和预防中心（CDC）的主要来源报道大约140万TBI每个事件年，其中近5万是致命的。美式足球就占了30多万科技企业孵化器，每年7。这种伤害的幸存者是在危险中对有关的感觉，认知和交流的长期神经系统并发症。这时，大约有530万美国人患有这些慢性病的缺点和残疾。直接和间接美国的医疗费用2000年至2010年总额为60十亿8。然而，这些数字没有考虑非医疗费用和损失，或者那些招致家人和朋友支持TBI患者。超越纯粹的经济分析，TBI诱导的残疾创建一个显著降低生活质量，可以表现为在家庭和社会一个显著负担。 需要进一步理解的形成，表征和预防的TI的是明确的。导致TI提供的洞察力和机会，以减少暴露或改善安全功能为那些在为TI潜在风险的基本机制的生物力学研究。此外，TI的形成一般的理解更加进步可以提高诊断的方法和标准，提供医疗专业人士谁TI治疗与改善预后更好的手段S和拯救生命。 都需要更好地了解损伤机制和更好地了解受伤发展生物力学的发展对人体有效的保护措施。从历史上看，模拟旨在预测伤病已经阻碍了采用计算的限制，以及解剖的保真度和材料模型。全身模拟已经集中在对每个正文部分的整体负载，但局部应力，应变和损伤的各器官，肌肉，骨骼等尚未观察。例如，肩时刻型号使用臂，负荷，以及所施加的角的尺寸，以搜索指定一个特定的场景是否是危险的表格值。的计算，自然是为快速估计有帮助，但不能捕捉到什么地方从手一路发生在肩部，尤其是在损害和伤害本质上是本地的。其次，FE simulations已被用来捕捉本地响应。在这些努力的限制一直没有FEA本身，而是定义爆炸伤荷载作用下身体的每个部位的行为的材料模型。以前使用的材料模型改编自简单的材料，并没有努力捕捉生物组织表现出复杂的机械行为的无数。因此，高保真计算模型与人体器官ISV材料模型代表了最现实的方式来调查TI的物理学和生物力学，设计创新的防护装备，并建立损伤指标更好的标准。 背景拆分霍普金森压杆（SHPB）和内部状态变量（ISV）材料模型 由于涉及体内试验人体器官和大规模人类尸体测试相关的后勤问题，在CURR伦理问题耳鼻喉科的研究工作包括使用从机关从动物中提取的代理人准备标本力学实验在体外 （ 例如 ，猪作为最常用的替代）。聚合物SHPB一直是体外测试软生物材料在高应变率的首选方法。从SHPB从组织的显微结构特征的测试和相应的组织损伤有关的信息的相关变形行为纳入我们的ISV材料模型器官机械描述9-10。这些材料模型，然后落实到我们的虚拟人体模型来进行各种伤病的有限元分析。这个过程使我们能够走向的准确预测的损伤的物 ​​理和性质为不同的机械载荷的条件下一个给定的器官（ 例如，鼓风诱导，车祸和钝的影响），而不需要进一步的物理实验的目标。为了准确地描述牛逼他现象的机械性能，特别是更高水平的应变速率依赖性，在人体内的FE模拟中使用的生物材料，SHPB实验上的生物材料以获得在有关人力TI的应变率动态力学响应。在SHPB设置在密西西比州立大学（MSU）的中心高级车辆系统（CAVS），概述是在图1。 以前的研究已经表明，SHPB试验具有与之相关联的12-18三大缺陷。在第一和最显著一个是材料惯性效果，其示出了在生物材料样品的作为初始尖峰的高应变速率机械响应。为了克服这个问题，以前的研究工作表明从圆柱形修改试样的几何形状在形状上立方形或环形形状。从这些研究得到的力学行为是不同的回回米彼此因为试样的几何形状影响波的传播，波的相互作用，以及机械响应。这种类型的修饰的试样的几何形状导致了生物材料的机械响应（多轴和非均匀应力状态）的错误表示。第二个主要的缺陷是无法在测试过程中保持动力的平衡。研究人员通过减少样品厚度与直径的比率和/或冷冻的组织在测试之前克服了这个问题。同时减少了样品的厚度与直径的比率寻址动态力平衡的问题，冻结的组织进一步复杂的测试过程，因为它改变了材料的性能由于存在于组织中的水的结晶。多项研究完全放弃了SHPB以避免上述缺陷，并用于冲击管，以获得在各种动物模型（大鼠，猪等 ）的压力-时间响应。但是，这些一IMAL机型不给予必要在有限元模拟中使用的材料模型一维单向应力 - 应变行为。第三缺陷是SHPB的失败，得到，因为滚筒抛光试样的一维应力 - 应变的结果，由于该材料的柔软性和在试样含水量的量。 因此，SHPB提出了一个可行的测试设备，以争取高应变率数据。为软质材料，但是，SHPB诱导产生三维应力状态主要由静水压力膨出，但一维的应力 - 应变数据是需要的。我们在这里展示一个人如何仍然可以使用SHPB争取为材料模型校准的一维单向真实应力 - 应变曲线;然而，涉及在获得单轴真应力 - 应变曲线的过程是复杂的。此过程既包括多轴实验数据和有限元模拟的结果，它需要的迭代校准材料模型常数。该一维实现在MATLAB中的ISV材料模型，也称为料点模拟器中，需要一维实验数据的校准。因此，ISV材料模型是使用系统校准过程优化。在这里，从SHPB测试实验数据被认为是在波浪理论的制定和动力平衡（MSU高速率的软件）的范围内。以占聚合物SHPB，粘弹性色散方程的粘弹分散，据报道由Zhao 等人 （2007），在MSU高速率软件实施的。粘弹性色散方程有助于确保动力的平衡，同时测试。所述一维物质点模拟器然后在一对夫妇实验-FE建模方法的上下文调整，直到这两个过程被认为是适当的兼容的，即，来自两个数据吻合较好。这些数据是用于通过比较在MATLAB材料响应仿真的（一维）的机械响应和SHPB有限元模型的（一维）试样中心线应力调整ISV模型材料常数。在这里，有限元模型的样本应力分量是沿着波浪荷载方向。然后有限元模型试样的三维行为校准通过反复进行有限元模拟和调整的ISV常量，使得体积平均装载方向应力与实验真应力 - 应变响应很好的相关性。因此，实验数据，有限元分析结果，和一维的ISV材料模型之间迭代优化过程进行的。 表1给出的ISV材料模型（MSU TP 1.1版）11的变量的汇总。 最重要的元素，以这种方法是获得生物材料的一维机械响应和其材料参数对于ISV材料模型，规避该应力状态的非均匀性的SHPB测试问题。它也分离出从惯性效应所产生的生物材料的初始非线性响应并呈现一个机械响应是固有的材料。耦合方法也表明，在试样的几何形状的变化完全改变了边值问题（BVP）和装载方向真应力 - 应变试样。这样，上述方法可用于任何材料模型（现象或显微为主），用于校准，然后损害机械载荷下模拟人体器官的高应变速率的行为。

<table border="0" cellpadding="0" cellspacing="0" width="951">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:699px;">Description</td>
			<td style="width:141px;">Provider</td>
			<td style="width:53px;"></td>
			<td style="width:59px;">Quantity</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">High pressure 316 stainless steel threaded pipe fitting, 1/2 male x 1/4 female pipe size, hex reducing bushing</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Type 316 stainless steel threaded pipe fitting, 3/4 male x 1/4 female, hex reducing bushing 150 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Easy-maintenance type 316SS ball valve, with 316 stainless steel ends, 1/2&#34; NPT female</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Easy-maintenance type 316SS ball valve, with 316 stainless steel ends, 3/4&#34; NPT female</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">ASME-code stainless steel pop-safety valve, 1/4 NPT male, 300 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Precision extreme-pressure 316SS pipe fitting, 1/2 x 1/2 pipe size, 1-7/8&#34; length, hex nipple</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">8</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">type 316 stainless steel threaded pipe fitting, 1/2 pipe size, tee, 150 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Test gauge with safety case, polyester case, standard, dry, 600 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Digital gauge, plastic case, 2-1/2&#34; dial, 1/4 bottom connection, 300 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Type 316 stainless steel 37 degree flared tube fitting, adapter for 1/4&#34; tube OD x 1/8&#34; NPT male pipe</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">12</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">303 stainless steel 37 degree JIC swivel fitting for 3/16&#34; ID</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">12</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">High-pressure chemical hose, 3/16&#34; ID, 0.312&#34; OD, 3000 psi</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">6</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">High-Purity Gas Regulator Single-Stage, Nitrogen, 0-125 PSI, CGA #580</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hose for Nitrogen Gas, Argon, and Oxygen Brass Fem Fittings, PTFE Hose, 3&#39;L, 1/4&#34; ID, 3600 PSI</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Extreme-Pressure 316 SS Threaded Pipe Fitting 1/4 X 1/4 Pipe Size, Hex Nipple</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">4</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Extreme-Pressure 316 SS Threaded Pipe Fitting 3/4 X 3/4 Pipe Size, Hex Nipple</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Extreme-Pressure 316 SS Threaded Pipe Fitting 1/4 Male X 1/8 Female Pipe Size, Hex Bushing</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Standard Brass Compression Tube Fitting Adapter for 1/4&#34; Tube OD X 1/4&#34; NPTF Male Pipe</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">4</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Kobalt 1/4 in Mini Regulator with Gauge</td>
			<td>Lowes</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1/4&#34; x 25 ft polyethylene tubing</td>
			<td>Lowes</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1-1/2&#34; Diameter Polycarbonate (PC) Rod</td>
			<td>McMaster-Carr</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">LTV-35 4-Way Valve Mead Fluid Dynamics</td>
			<td>Motion Industries</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Pneumatic double action actuator</td>
			<td>Valtronic</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Stainless Steel Ball Valve 1/2&#34;</td>
			<td>Valtronic</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Buckeye pressure vessel</td>
			<td>Buckeye</td>
			<td></td>
			<td align="right">2</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;">SR-4 General Purpose FAE-25-35SX Strain Gages</td>
			<td style="width:141px;">Micro-Measurement Vishay Precision Group</td>
			<td style="width:53px;"></td>
			<td align="right">2</td>
		</tr>
		<tr height="60">
			<td height="60" style="height:60px;">M-M Signal Conditioning Amplifier 2310A</td>
			<td style="width:141px;">Micro-Measurement Vishay Precision Group</td>
			<td style="width:53px;"></td>
			<td align="right">1</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Laser ROLS-W optical sensor</td>
			<td>Monarch Instruments</td>
			<td></td>
			<td align="right">1</td>
		</tr>
	</tbody>
</table>

a coupled experiment-finite element modeling methodology for assessing high strain rate mechanical response of soft biomaterials

这项研究提供了一个联合实验和有限元（FE）模拟方法用于检查时暴露在高应变率软生物材料（ 如脑，肝，肌腱，脂肪等 ）的力学性能。本研究采用分离式霍普金森压杆（SHPB）生成的100-1,500秒的应变率-1。该SHPB采用的撞杆组成的粘弹性材料（聚碳酸酯）的。获得生物材料样品死后不久和SHPB测试做好准备。将试样的入射光和透射杆之间，并且SHPB的气动元件被激活，以驱动锤杆朝向入射杆。由此产生的碰撞所产生的压缩应力波（ 即入射波），通过这一事件吧旅行。当压缩应力波到达入射杆的末端，一个部分继续向前通过样品和传送杆（一.E。透射波），而另一部分通过事件杆作为拉伸波反转（ 即反射波）。这些波是用安装在入射光和透射杆应变计测量。样品的真应力 - 应变行为是从根据波传播和动态力平衡方程来确定。该实验的应力 - 应变响应是三维的性质，因为在试样鼓出。这样，静水压力（第一不变量）被用来产生的应力 - 应变响应。以提取的单轴（一维）的机械组织的响应，使用实验结果和有限元分析（FEA），​​它包含了一个用于组织内部状态变量（ISV）材料模型进行迭代耦合优化。在实验装置的有限元模拟中使用的材料，ISV模型反复校准（ 即优化）的实验数据，塔T中的实验和有限元分析应变值和应力第一不变量是很好的一致性。

<html>耦合方法的有效性是例示在图3中，在这里对大脑的SHPB试验应力-应变响应是在一个较低的应力状态（0.32兆帕的峰值应力）相比于一维材料的应力状态点模拟器（具有0.74的峰值兆帕），这是类似于对FE样品中心线（元件）的平均值。这是由于变形软生物材料表现出的性质。因为应变率很高，并且该生物材料的波的速度和强度低，在材料需求的非均匀变形的惯性和应力波的传播。这?...

Watch this Scientific Journal Video about A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials at JoVE.com

A Coupled Experiment-finite Element Modeling Methodology for Assessing High Strain Rate Mechanical Response of Soft Biomaterials

目前的研究规定了耦合实验-有限元模拟方法获得的软生物材料（脑，肝，肌腱，脂肪等 ）的单轴动态力学响应。那出现的多轴实验的结果，因为样品的从斯普利特 - 霍普金森压杆测试鼓胀获得通过时，生物材料的有限元分析的迭代优化模拟被渲染到单轴真应力 - 应变行为。

一个耦合试验，有限元建模方法以评估生物材料软的高应变率力学响应

This study offers a combined experimental and finite element (FE) simulation approach for examining the mechanical behavior of soft biomaterials (e.g. ...

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JoVE Journal

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