## 3 Results
### Strength Characteristic Analysis  
The PCCY test group and ACCY test group are compared with each other. Under the condition of similar impact speeds and approximate strain rates, the addition of aluminum oxide fiber will have an impact on the dynamic compressive strength of the specimen. Based on the PCCY test group, the increase or decrease in the dynamic compressive strength of the specimen mainly depends on the amount of fiber. The results of linear fitting between dynamic compressive strength and strain rate are shown in Formula (2), which can be obtained from Figure 2. In Formula (2), there is a quadratic function relationship between the fiber content and the dynamic compressive strength of the specimen. The peak point appears in the 2 ACCY test group with the fiber content of 0.2%. When the strain rate is 65 \(\pm\) 5 s\({}^{-1}\), the strength increases by 29.31%. When aluminum oxide fiber is added in excess, the fiber content is negatively correlated with the overall compressive strength. Compared with the PCCY test group under the condition of similar impact speeds and approximate strain rates, the dynamic compressive strength of the 4 ACCY test group and the 5 ACCY test group is lower than that of the PCCY test group. For example, when the strain rate is 110 \(\pm\) 5 s\({}^{-1}\), the dynamic compressive strength is weakened by 7.82% and 9.56%, respectively. Compared with the best static compressive strength test group, the effect of fiber on the improvement of dynamic compressive strength is more significant. The appropriate amount of fiber will increase the value of strength growth factor. This kind of situation is mainly due to the difference in the strengthening effects of fiber on concrete matrix materials under different load types. Under the influence of fiber, the growth rate of static compressive strength is slower than that of dynamic compressive strength. The difference between the two is another expression of strength growth factor. However, there is no significant correlation between the increasing rate of strength growth factor of each group of specimens, that is, the slope of the fitting curve in Formula (3), and the fiber content.  
\[\left\{\begin{array}{ll}\text{PCCY}:&f_{c,d}=36.0560+0.5688\tilde{\overline{e}} &(R^{2}=0.9521)\\ 1\text{ACCY}:&f_{c,d}=31.5628+0.6581\tilde{\overline{e}}&(R^{2}=0.9964)\\ 2\text{ACCY}:&f_{c,d}=46.5679+0.6172\tilde{\overline{e}}&(R^{2}=0.9702)\\ 3\text{ACCY}:&f_{c,d}=47.4656+0.5274\tilde{\overline{e}}&(R^{2}=0.9974)\\ 4\text{ACCY}:&f_{c,d}=36.0560+0.5688\tilde{\overline{e}}&(R^{2}=0.9521)\\ 5\text{ACCY}:&f_{c,d}=33.8856+0.4809\tilde{\overline{e}}&(R^{2}=0.8611)\\ \end{array}\right. \tag{2}\]  
\[\left\{\begin{array}{ll}\text{PCCY}:&l_{c}^{d}=0.5973+0.0095\tilde{\overline {e}}&(R^{2}=0.9501)\\ 1\text{ACCY}:&l_{c}^{d}=0.5098+0.0103\tilde{\overline{e}}&(R^{2}=0.9597)\\ 2\text{ACCY}:&l_{c}^{d}=0.7045+0.0093\tilde{\overline{e}}&(R^{2}=0.9899)\\ 3\text{ACCY}:&l_{c}^{d}=0.7238+0.0078\tilde{\overline{e}}&(R^{2}=0.9950)\\ 4\text{ACCY}:&l_{c}^{d}=0.5473+0.0093\tilde{\overline{e}}&(R^{2}=0.9076)\\ 5\text{ACCY}:&l_{c}^{d}=0.6508+0.0082\tilde{\overline{e}}&(R^{2}=0.8686)\\ \end{array}\right. \tag{3}\]