## 5 Conclusions  
This study presented the pullout test results of a reinforcement that improved existing steel reinforcements on the basis of one resistance mechanism in the most pullout resistance. The improved reinforcement has smooth steel strip reinforcement with transverse members, and it had an evenly distributed friction resistance and bearing resistance. The test results obtained in this study led to the following conclusions:  
1. The bearing-resistance effect of the total pullout resistance was not related to the effective length of reinforcement in the resistance zone because the installed quantity of the transverse member is decided by soil conditions. Therefore, total pullout resistance of the improved reinforcement should be evaluated with friction resistance on the basis of effective length due to longitudinal members and bearing resistance due to transverse members, respectively. 2. Bearing strength based on the resistance of transverse members had little incremental effect when the value of normal stress and the quantity of transverse members were higher than certain values because it did not increase further. 3. The bearing bond coefficient considering the interference effect was rapidly decreased in initial normal stress, but it gradually converged when normal stress was more than a certain value. Therefore, the increment of the interference effect was caused by the increment of the transverse member and normal stress. 4. Therefore, in order to predict the number of transverse members, a prediction method is proposed using the relationship between bearing-resistance stress and bearing bond coefficient due to normal stress. This is a rational method for achieving the stability and economic efficiency of reinforced earth walls using the improved reinforcement. \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline  & \multicolumn{3}{c}{**Common Design Condition**} & \multicolumn{3}{c}{**General Design**} & \multicolumn{3}{c}{**Design Using Predicted Method**} \\ \hline
**Reinforcement No.** & **Embeded Height (m)** & **L\({}_{a}\) (m)** & **L\({}_{e}\) (m)** & **Safety Factor Criteria** & **Number of Transverse Members** & **Safety Factor (FS\({}_{\text{po}}\))** & **Number of Transverse Members** & **Safety Factor (FS\({}_{\text{po}}\))** \\ \hline
1 & 0.375 & 0.225 & 8.175 & & & 1.93 & 1 & 1.56 \\
2 & 1.125 & 0.675 & 7.725 & & & 1.90 & 1 & 1.51 \\
3 & 1.875 & 1.125 & 7.275 & & & 1.88 & & 1.88 \\
4 & 2.625 & 1.575 & 6.825 & & & 1.83 & & 1.83 \\
5 & 3.375 & 2.025 & 6.375 & & & 1.79 & & 1.79 \\
6 & 4.125 & 2.475 & 5.925 & & & 1.75 & & 1.75 \\
7 & 4.875 & 2.925 & 5.475 & & & 1.71 & & 1.71 \\
8 & 5.625 & 3.375 & 5.025 & FS\({}_{\text{po}}\geq 1.5\) & 2 & 1.69 & & 1.69 \\
9 & 6.375 & & & & & 1.67 & & 1.67 \\
10 & 7.125 & & & & & 1.68 & & 1.68 \\
11 & 7.875 & & & & & 1.74 & & 1.74 \\
12 & 8.625 & 3.6 & 4.8 & & & 1.86 & & 1.86 \\
13 & 9.375 & & & & & 2.13 & & 2.13 \\
14 & 10.125 & & & & & 2.81 & 1 & 1.64 \\
15 & 10.875 & & & & & & 2.81 & 1 & 1.64 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Design results on pullout resistance according to predicted method. **Author Contributions:** Conceptualization, [PERSON]-[PERSON], [PERSON] and [PERSON]; methodology, [PERSON]-[PERSON] and [PERSON]; validation, [PERSON]-[PERSON], [PERSON] and J.P.; formal analysis, [PERSON]-[PERSON], [PERSON] and J.P.; investigation, [PERSON]-W.L., [PERSON]-Y.L. and J.P.; resources, [PERSON]-G.H., [PERSON]-W.L. and [PERSON]-Y.L. ; data curation, [PERSON]-G.H., [PERSON] and J.P.; writing--original-draft preparation, [PERSON] and J.P.; writing--review and editing, [PERSON]-G.H., [PERSON]-W.L., [PERSON]-Y.L., [PERSON] and J.P.; visualization, [PERSON]-G.H., [PERSON]-W.L., [PERSON] and J.P.; supervision, [PERSON]-[PERSON] and [PERSON]-W.L. ; project administration, [PERSON]-W.L. and J.P. All authors have read and agreed to the published version of the manuscript.