To investigate the dynamic tensile behaviours of concrete and cement mortar, a 50‐mm split Hopkinson pressure bar was applied on Brazilian disc specimens for dynamic tensile experiments, in which strain rate varied from 10⁻⁵ to 20 s⁻¹. The high‐speed camera testing technique was used to capture the dynamic fractured process of the specimens at relative high strain rate. The experimental results revealed that the dynamic tensile strength of concrete specimens has a stronger strain rate effect than that of cement mortar specimens. Then three typical failure patterns of the specimens were confirmed in dynamic experiments. In addition, one‐parameter semi‐empirical relation between dynamic tensile strength and strain rate was established. Finally, the limitation of dynamic splitting experiments on Brazilian disc specimens was discussed in detail at high strain rate, in which the crack initiates from the contact point between the incident bar and specimens rather than the centre of the specimens.

中文翻译：

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混凝土和水泥砂浆的动态劈裂拉伸性能

为了研究混凝土和水泥砂浆的动态拉伸性能，在巴西圆盘试样上施加了50 mm的霍普金森分体式压力棒进行动态拉伸实验，其应变速率在10 ^-5到20 s ^{-1之间变化。}。高速相机测试技术用于捕获相对较高应变率下的动态断裂过程。实验结果表明，混凝土试件的动态抗拉强度比水泥砂浆试件具有更强的应变率效应。然后在动态实验中确定了三种典型的试样破坏模式。另外，建立了动态​​抗拉强度与应变率之间的一参数半经验关系。最后，在高应变率下详细讨论了在巴西圆盘试样上进行动态分裂实验的局限性，其中裂纹是从入射棒和试样之间的接触点而不是试样中心开始的。