*4.2. Average Strain Rate of 15.3 s*−*<sup>1</sup>*

The macro morphology of the ultra-early-strength cement-based material specimen after three repeated experiments, when the impact velocity is 10 m/s (the average strain rate is 15.3 s−1), can be seen in Table 4. It can be seen from the table that, at an impact velocity of 10 m/s, the specimen was severely damaged under the impact of the compression stress wave. Because of the short time of the load, cracks appeared throughout the whole specimen at the moment of impact and rapidly expanded until it broke into many smaller pieces. The stress–strain curve and the average stress–strain curve obtained by three repeated experiments are shown in Figure 6. The consistency of the repeated experiments is great.


**Table 4.** Test results at an impact velocity of 10 m/s.

**Figure 6.** Stress–strain curve of 10 m/s.
