冲击动力学研究中实测波信息的解读分析

Understanding and Interpreting of the Measured Wave Signals in Impact Dynamics Studies

分析了多点测量技术在解读和分析实测冲击波信息时的重要性和难点,提出了将Lagrange多点测量反分析与Hopkinson压杆技术相结合的新方法,解决了在同一个Lagrange位置上难以同时测量应力和质点速度波形的难题,对试样上不同Lagrange位置处实测质点速度波形进行了解读分析,由n个实测质点速度波形信息得到了各Lagrange位置处的动态应力-应变关系。以有机玻璃和水泥砂浆两种粘弹性试样为例,进行了数值计算,验证了该方法的可行性和有效性。

The significance and difficulty of the multi-position measuring were analyzed when understanding and interpreting the wave signals measured in impact dynamic experiments.By combining the Lagrange inverse analysis with the Hopkinson pressure bar technique,a new method was proposed,which substantially resolves the problem of measuring simultaneously both stress wave and particle velocity at a Lagrange position in impact tests.When the particle velocity wave signals at n（n ≥3） Lagrange positions are measured,by using this new method,the dynamic stress-strain curves at n Lagrange positions of specimen can be determined and interpreted.The feasibility and validity of this new method was consistently confirmed by numerical tests for two viscoelastic materials（PMMA and cement mortar）.