采用一维弹性应力波理论,实现了经典Hopkinson杆试验的计算机模拟,研究了试验“测得”(重构)的应力-应变曲线的精确度,并结合具体试验进行了分析.由于经典Hopkinson杆试验的基本计算公式中引入了“应力均匀性”假设,因此在有限应变范围内,重构的应力-应变曲线总是和输入(真实)曲线差异较大.结果表明,采用经典Hopkinson杆测量的弹性模量是不可靠的,因此实践中应慎用.
Computer simulations of conventional split Hopkinson bar tests were implemented by onedimensional elastic stress wave theory. The accuracies of measured (reconstituted) stress-strain curves were investigated,combining with an actual test. The results show that reconstituted stress-strain curves don ~t agree with the input curves,especially in a limited range of strain, because the assumption of uniform stress is introduced in the governing equations of conventional split Hopkinson bar theory. Therefore,the Young's moduli of materials measured by conventional split Hopkinson bar technique are not reliable, which implies that carefulness will be specially reguired in using this conventional method in practice.