With the material dynamic constitutive equation including damage and the effect of stain rate the predictable formula about ballistic limit velocity of fiber composite target . secondly based on the damage feature about ceramic / fiber composite target caused by impact load , analysis model about defense performance of ceramic / composite material target is formed and the predictable formula about ballistic limit velocity is also given . lastly using the reflection and projectile theory of stress wave the paper discusses the design of ceramic / composite material target , optimizes the design of double layer ceramic / composite targets , gains optimal coefficient under certain area density and discusses the variety relationship of area density and thickness with optimal coefficient u nder some ballistic limit velocity 3 首先，分析了纤维类正交铺层复合靶板在冲击载荷作用下的损伤破坏机理，结合包含损伤和应变率效应的材料动态本构方程，建立了纤维复合材料板弹道极限速度的预测公式；其次，根据陶瓷/纤维材料复合靶板在冲击载荷下的破坏特点，建立了陶瓷/复合材料靶板抗弹性能分析模型，给出了弹道极限速度预测公式；最后，利用应力波反射和透射理论讨论了陶瓷/复合材料靶板的设计问题，对双层陶瓷复合靶板的优化设计进行了分析，给出了在一定面密度下的最佳优化系数，讨论了一定弹道极限速度下的面密度和厚度随优化系数的变化关系。
The main crack of tiaohu formation are straight oblique - cracks and level crack , there are many scores in the crack . the length of cracks is long , and they cut across several layers . the average surface density of the cracks is 0 . 101 slips / m . the cracks in lucaogou formation is mostly net cracks , and there are solution on crack surface 条湖组的裂缝多为平直的斜交缝和水平缝，缝面多见擦痕，延伸长度大，切穿多套地层，裂缝面密度平均为0 . 101条米；芦草沟组裂缝多为网状裂缝，缝面有溶蚀现象，多存在于碳酸盐岩内，裂缝面密度平均为0 . 143条米。
And collecting the image of the damage instance in the sample of pmma in real time on line , we get the surface crazing damage density under different time and different stress passing the image dispose of a software , and giving out a changing rule that the change of the sample of pmma ' s surface crazing damage density follow the change of time and stress 对pmma试件银纹损伤情况进行在线实时的图像采集，经图像处理软件的分析，得到了pmma试件在不同时间和不同应力水平下的银纹损伤面密度，并给出了pmma试件银纹损伤面密度随时间和应力的变化而变化的规律。
At the same time we study , analysis and discuss the action that non - linearity - stickiness - springiness and crazing damage of the pmma sample under creep though making us of the knowledge about the high molecule physics the damage theory of material of rheology of bodies with defects . through the study and theory analysis of single - axes stretching experiment in pmma sample under creep , take the surface crazing damage density of pmma sample as an variable , to look for a commonly rule that the crazing damage of pmma , and to offer a feasible damage model for the sake of study that of pmma ' s remoteness damage 同时运用高分子物理、含缺陷流变性物体的材料破坏理论等知识，对无孔洞pmma试件和有孔洞pmma试件蠕变条件下非线性粘弹性行为及其银纹损伤现象进行了研究、分析与探讨，通过对蠕变条件下的pmma试件的单轴拉伸实验研究和理论分析，以pmma试件的银纹损伤面密度值为损伤变量，来尝试寻求pmma银纹损伤的一般规律，为研究pmma的细观损伤提供了一种可行的损伤模型。
The pmma ' s craze damage is observed on line in different temperature and invariable load , which show that the change pricks up with the increase of time and temperature . with the disposal of the image , we get a changing rule that the change of the sample of pmma ' s surface crazing damage density follow the change of time and stress . then the data from experiment is to match in non - linearity , pmma ' s density of crazing damage changing with time and stress is available 对pmma在恒定荷载作用下，不同基温下的pmma银纹损伤进行了实时在线观测，结果表明： pmma试件的银纹随持荷时间增加，而且随着温度的升高，可以加剧这种银纹随时间的变化；经图像处理，得到了不同基温下、不同应力水平下， pmma试件银纹损伤面密度值；进而，对所得数据进行非线性拟合，得到pmma试件银纹损伤密度随时间演化规律，以及应力水平依赖性； 3
