## 5 Conclusions  
In this study, the design, production and the quasi-static testing of an ultra-high-strength (performance) concrete were carried out, leading to an average compression strength range of 125 to 135 MPa. These average values were measured for the samples tested on the 28 th and 56 th days following production. For the quasi-static compression tests, four sets of cylindrical samples with \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \(\rho\) (kg/m3) & **G,GPa** & **A** & **B** & **C** & **N** & **fc,MPa** & **T,MPa** & **EPSo** \\ \hline
2700 & 33.2 & 0.30 & 1.50 & 0.01 & 0.59 & 135 & 8.4 & 1.00 \\ E\({}_{\rm fmin}\) & \({\rm S}_{\rm max}\) & \({\rm P}_{\rm crush}\)GPa & \({\rm P}_{\rm lock}\),GPa & D1 & D2 & K1,GPa & K2,GPa & K3,GPa \\
0.001 & 12.5 & 0.162 & 0.000095 & 0.003 & 1.000 & 16.2 & \(-\)40 & 26 \\ \hline \end{tabular}
\end{table} 
Table 4: Parameters of JHC model for 135 MPa compressive strength concrete. the dimensions of \(\mathcal{O}150\times 300\) mm were used. In the SPHB tests, a total of 21 specimens with height/diameter ratios varying between 0.6 and 1.2 were used. The concluding remarks that may be drawn from this study are given below:  
* A new ultra-high-strength concrete mixture is designed, produced and tested under quasi-static and dynamic loading conditions. * For quasi-static loading, the average compressive strength of the new mixture, depending on the testing day following production, varied between 108 and 135 MPa. * For the dynamic testing conducted on a SHB test ring, it was observed that, for the same test conditions, as the height/diameter of a sample decreases, the measured strain rate increases. * As expected, an increase in the test pressure increases the striker speed linearly. As a result of this, one can obtain the high strain rate deformation characteristics of the ultra high-strength concrete. * High-strength concrete appeared to be sensitive to deformation rate. While the strain rate was \(10^{-5}\) s\({}^{-1}\) in quasi-static tests, the strain rate in the dynamic tests was measured in the range of 353-1288 s\({}^{-1}\). * The maximum compressive stress values measured in the dynamic tests were observed to be 1.06-1.87 times higher than the quasi-static compression test average maximum compressive stress value of 135 MPa measured for specimens tested 56 days after production. * Since the high-strength concrete has locally different constitutional characteristics (due to the aggregate, cement, GGBF slag, etc. distribution), it is considered that the strength performance at high strain rates may lay out in the range of 143-253 MPa. * Generally, as the peak strain rate increases, the corresponding maximum compressive stress value appears to decrease. * Time variations of stress, strain and strain rates recorded during the SPHB tests have been fitted to the JHC material model using an in-house developed computer code of multi-variable regression. * The achieved strain rate values have been measured to be in the range that is generally observed in impact and blast conditions. Therefore, one may conclude that the model parameters determined are suitable for numerical simulations of this 135 MPa strength concrete. In future work, ballistics tests on developed concrete samples are planned to determine the response of the UHSC under impact and blast loadings. In order to reduce the cost of such expensive tests, a numerical simulation program should be performed. This study is the first step towards achieving this objective. **Author Contributions:** Methodology, A.R.G. ; writing--original draft preparation, A.R.G. ; validation, M.K. ; writing--review and editing, S.K. and M.K. ; supervision, S.K. All authors have read and agreed to the published version of the manuscript. **Funding:** This research received no external funding. **Acknowledgments:** This study was supported by YAPIRAY and TUBITAK SAGE. The authors acknowledge [PERSON] from YAPIRAY and [PERSON] from TUBITAK SAGE for their contributions to the studies on sintering.