外载荷作用下高聚物粘结炸药的损伤分析与建模研究

项目名称： 外载荷作用下高聚物粘结炸药的损伤分析与建模研究

项目编号： No.U1330101

项目类型： 联合基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 白树林

作者单位： 北京大学

项目金额： 88万元

中文摘要： 通过力学性能实验、微缺陷观测、数值模拟与理论建模相结合的方法，开展外载荷作用下高聚物粘结炸药损伤的分析与研究。首先分别采用循环拉伸和压缩、阶次冲击的实验方法，获得高聚物粘结炸药在不同加载速率作用下的力学行为及相应的力学性能；然后采用高能X射线技术、三维原位CT成像技术和超声显微技术测定材料内部微裂纹和微孔洞的尺寸、数量和分布，完成图像的三维重构和相应的微缺陷统计分析，获得单位体积微缺陷密度与弹性模量的对应关系；进而建立以界面裂纹开裂和扩展为主要损伤机制的细观力学理论模型，重点研究基体材料的粘性对于损伤的产生和演化的效应；进一步利用有限元方法进行微缺陷演化过程的数值模拟。最后，将实验、观测、理论和数值模拟结果相结合，建立高聚物粘结炸药损伤表征和预测的一套理论和实验方法，为高聚物粘结炸药的安全性评价提供可靠的理论和实验依据。

中文关键词： 高聚物粘接炸药；静动态力学性能；损伤机理；破坏；

英文摘要： By the combination of mechanical tests, microscopic observation and measurements, numerical simulation and and theoritical modeling, the damage analysis and study on polymer bonded explosives (PBX) under load will be carried out. Firstly, by cyclic tensile and compressive tests, as well as stepping impact tests, the mechanical behaviour and properties of PBX under different loading rates will be obtained. Then, by using high energetic X-ray, in situ 3D-CT and scanning acoustic microscopy, the size, quantity and distribution of microcracks and microvoids in the sample will be measured, and a reconstruction and a statistic analysis of microdefects will be completed. A relationship between the microdefect density par unit volume and the elastic modulus will be established. Further, a mesomechanical model will be proposed to predict the damage mainly controlled by the interfacial cracking and propagation. The emphasis is put on the effect of matrix viscosity on the damage initiation and development. The finite elements method will be further used to give the numerical simulation of damage evolution. Finally, by combining the experimental, observation, theoretical and numerical results, a series of theoretical and experimental methods for the damage evolution and prediction of PBX will be established, which will prov

英文关键词： PBX；static and dynamic properties；damage；failure；