# Design and Mechanical Properties of Flat Anchorage Limit Plate
## 4 Mechanical Properties of Flat Anchorage Limit Plate
### Five-Hole Tensile Stress Distribution  
When tensioning the fifth hole, only five situations were considered, i.e., with the last tensioning hole a hole 1, 2, 3, 4, or 5, as shown in Table 6. Figure 10 depicts the simulation results for tensioning the fifth hole. Combined with the data in Table 6, we found that the extreme stress of the anchorage dropped by 12.83%, showing that the proposed system still played an important role in relieving stress concentration. By comparing the five working conditions, we found that, when the holes on both sides of hole 3 were symmetrically stretched first and then hole 3 was stretched, the extreme anchorage stress value was the smallest in both cases. According to the results in Sections 4.1-4.4, the symmetrical tensioning scheme represented by the sequential tensioning of holes 1, 4, 2, 5, and 3 should be adopted in tensioning, which not only ensures that the anchorage stress is not too large in the tensioning process but also results in a smaller final stress extreme value. The standard deviation of the stress extreme of the conventional flat anchorage was 18.63 kPa, and that of the new flat anchorage system was 8.37 kPa. The limit plate reduced the dispersion of five-hole tension results, and the differences between the different schemes were small. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Tension Hole Position** & \ \begin{tabular}{c} **Maximum Equivalent Stress of** \\ **Conventional Flat Anchorage (kPa)** \\ \end{tabular}  & \begin{tabular}{c} **Maximum Equivalent Stress of Anchorage** \\ **in New Flat Anchor System (kPa)** \\ \end{tabular}  & **Decrease (\%)** \\ \hline
1, 2, and 3 & 760.79 & 675.88 & 11.2 \\
1, 2, and 4 & 755.70 & 668.45 & 11.5 \\
1, 2, and 5 & 756.93 & 663.29 & 12.4 \\
1, 3, and 2 & 526.69 & 487.43 & 7.5 \\
1, 3, and 4 & 526.77 & 487.77 & 7.4 \\
1, 3, and 5 & 523.34 & 484 Figure 9: Tensile stress distribution of holes 1–4: (**a**) conventional flat anchorage, and (**b**) anchorage of new flat anchor system. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Tension Hole Position** & \ \begin{tabular}{c} **Maximum Equivalent Stress of** \\ **Conventional Flat Anchorage (kPa)** \\ \end{tabular}  & \begin{tabular}{c} **Maximum Equivalent Stress of Anchorage** \\ **in New Flat Anchor System (kPa)** \\ \end{tabular}  & **Decrease (\%)** \\ \hline
1, 2, 3, and 4 & 804.09 & 703.72 & 12.48 \\
1, 2, 3, and 5 & 804.71 & 697.85 & 13.28 \\
1, 2, 4, and 3  
Figure 11 further shows the development curves of the extreme stress values of several tensioning sequences, with the corresponding numbers in the curves denoting the tensioning sequences. For example, \"14253\" denotes the sequential tensioning of the steel strands of holes 1, 4, 2, 5, and 3. As shown in the figure, different tensioning sequences showed gentle stress development; however, the periods of gentle change slightly differed. Regardless of the curve, the final values did not widely differ. Throughout the process, the stress extremes of the two schemes of the final tensioning of hole 3 were small, with a final stress extreme of 685.55 kPa, representing a 22.42 kPa difference from the scheme \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Tension Hole Position** & \begin{tabular}{c} **Maximum Equivalent Stress of** \\ **Conventional Flat Anchorage (kPa)** \\ \end{tabular} & \
\begin{tabular}{c} **Maximum Equivalent Stress of Anchorage** \\ **in New Flat Anchor System (kPa)** \\ \end{tabular} &
\begin{tabular}{c} **Decrease (\%)** \\ \end{tabular} \\ \hline
2, 3, 4, 5, and 1 & 802.84 & 699.87 & 12.83 \\
1, 3, 4, 5, and 2 & 808.61 & 707.97 & 12.45 \\
1, 2, 4, 5, and 3 & 762.37 & 685.55 & 10.08 \\
1, 2, 3, 5, and 4 & 803.31 & 703.15 & 12.47 \\
1, 2, 3, 4, and 5 & 797.87 & 698.15 & 12.50 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Extreme value of five-hole tensile stress. Figure 10: Tensile stress distribution of holes 1-5: (**a**) conventional flat anchorage, and (**b**) anchorage of new flat anchor system. with the largest stress extremes.