## 5 Conclusions  
This study investigated the effects of curing temperature and curing time on the compressive, flexural, and bond strengths of polysulfide polymer concrete through a series of laboratory tests. The following conclusions were drawn from the results of this study:  
1. In the polysulfide polymer concrete used for this study, approximately 27% of the compressive strength at 672 h (28 days) developed after approximately 6 h of curing, and approximately 80% of the compressive strength developed within 168 h (7 days). These development times are considerably shorter than those for cement concrete. Furthermore, the greater the curing temperature, the more consistently low the compressive strength. In particular, some specimens could not achieve the minimum compressive strength value of 34 MPa recommended in the ACI 548.9 guideline, despite their longer curing times. It was also found that curing temperatures above 40 \({}^{\circ}\)C have an adverse effect on the compressive strength of polysulfide polymer concrete.
2. The development of flexural strength depended significantly on the curing temperature. The flexural strength decreased gradually up to a curing temperature of 20 \({}^{\circ}\)C and then decreased rapidly above this temperature. The specimens cured at temperatures above 40 \({}^{\circ}\)C showed a flexural strength value lower than 14 MPa, which is the minimum value recommended in the ACI 548.5 guideline.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Curing Temperature**} & \multicolumn{3}{c}{**Strength Ratio**} \\ \cline{2-4}  & **Flexural/Compressive** & **Bond/Compressive** & **Flexural/Bond** \\ \hline (\({}^{\circ}\)**C**) & **(-)** & **(-)** & **(-)** \\ \hline \(-10\) & 0.487 & 0.107 & 0.221 \\ \(5\) & 0.521 & 0.148 & 0.283 \\ \(20\) & 0.566 & 0.106 & 0.187 \\ \(40\) & 0.421 & 0.140 & 0.334 \\ \(60\) & 0.384 & 0.113 & 0.295 \\ \hline Average & 0.476 & 0.123 & 0.264 \\ \hline \hline \end{tabular}
\end{table}
Table 8: Summary of strength ratios of polysulfide polymer concrete.  
3. Tests for assessing the bond strength between polysulfide polymer concrete and steel showed an average bond strength of 4.8 MPa, and the bond strengths for all the curing temperatures considered in this test were higher than 1.7 MPa, which is the minimum value recommended in the ACI 548.9 guideline.
4. Regression analyses of the relationships between the flexural and compressive strengths and between the bond and compressive strengths revealed very large correlation coefficients of 0.983 and 0.940, respectively. These values indicate that the regression equations derived from the results can be effectively used to estimate the flexural and bond strengths from a known value of compressive strength.
5. In this study, the effects of curing temperature and curing time on polysulfide polymer concrete were assessed. However, these results hold true only under laboratory conditions. Accordingly, additional laboratory tests and on-site tests need to be conducted in the future in order to draw more generalized conclusions regarding the properties of polysulfide polymer concrete.  
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) and funded by the Ministry of Education (NRF-2016R1A6A3A11931804).  
[PERSON] performed the experiments and wrote the paper.  
The authors declare no conflict of interest.