## 3 Results
### Shockwave Energy Analysis  
Figure 6 illustrates the influence of shock waves on the strain of concrete blocks during electrical explosion experiments using various dielectric media. The results demonstrate that while there are differences in shock wave peak values and durations across different dielectric media, the overall response pattern exhibits a cyclic alternation between tensile and compressive stresses. In the initial phase, the primary shock wave causes the concrete block to expand outward, resulting in the stretching of the attached strain gauges and an increase in strain values. Consequently, the potential energy of the system rises. As the concrete block reaches its maximum deformation, the combined effects of potential and kinetic energy initiate a contraction phase that surpasses the equilibrium position. After contracting to a certain extent, the block gradually returns to its equilibrium state. Following the primary shock wave, secondary shock waves were generated due to varying reactions between different dielectric media and the metal wire. These secondary waves initiated another deformation cycle in the concrete block. Analysis of the strain waveforms revealed that, with the exception of the CO\({}_{2}\)-dissolved liquid (Figure 6g), where the contraction state dominated compared to the tap water control group (Figure 6h), the remaining six dielectric media predominantly exhibited expansion states. When correlated with the concrete block fragmentation effects, it was observed that the expansive action was more conducive to increasing damage and improving rock-breaking efficiency. Through the analysis of the strain-response curves and the application of Equation (7), we calculated the equivalent shock wave energy values under different dielectric media conditions. The specific data are presented in Table 3.  
Comparative analysis of strain waveforms from aluminum powder suspension (Figure 6a) and iron powder suspension (Figure 6b) groups with the tap water control group (Figure 6h) revealed elevated expansive strain peak values of 2911 \(\mu\)e and 2406 \(\mu\)e, respectively, corresponding to increases of 8.9% and 7.4%. The strain waves predominantly remained above the equilibrium position, indicating that the concrete blocks primarily underwent expansive deformation, with the contraction phase lasting no more than 0.05 ms. Furthermore, calculations from Table 3 demonstrate that the shock wave energy conversion efficiencies for aluminum and iron powder suspensions were 16.5% and 16.2%, respectively,slightly surpassing the 14.1% efficiency of tap water. Both aluminum and iron powder suspension groups exhibited secondary, albeit weaker, shock waves following the initial impact. This suggests that the electrical explosion that set micron-sized metal powder on fire effectively slowed down the rock's shrinking phase and kept the shock wave effect going, which backs up what was found in [18]. Figure 6: _Cont_. Comparative analysis of strain waveforms from copper (II) oxide powder suspension (Figure 6c) and iron (III) oxide powder suspension (Figure 6d) groups with the tap water control group (Figure 6h) revealed a significant enhancement in shock wave amplitude and an increase in the number of secondary shock waves. The expansive strain peak values for the copper (II) oxide and iron (III) oxide groups exceeded those of the tap water group by 16,092 \(\mu\)\(\varepsilon\) and 21,002 \(\mu\)\(\varepsilon\), respectively, corresponding to substantial increases of 49.7% and 64.8%. Unlike metal powder suspensions, metal oxide suspensions induced more pronounced contraction in the concrete blocks. Contraction peak values reached 10,558 \(\mu\)\(\varepsilon\) and 10,850 \(\mu\)\(\varepsilon\) for copper (II) oxide and iron (III) oxide groups, respectively, representing increases of 29.5% and 33.1% compared to the control. These results underscore the significant role of metal oxide suspensions in enhancing the contraction phase of concrete blocks.