## 3 Material Testing of Window-Type NBSDs and the Results
### NBSD Material Test Results and Analysis
The average cumulative energy dissipation (\(E_{D,ave}\)) was measured to be 117.8 kN\(\cdot\)m. The average equivalent damping ratios (\(\beta_{eq,ave}\)) were 0.31 (11 mm), 0.38 (22 mm), and 0.38 (33 mm), respectively. The results showed that the equivalent damping ratios increased with increasing displacements, indicating that energy can be efficiently dissipated even when the deformation is large. Accordingly, this NBSD system was expected to provide an excellent damping effect when applied to RC buildings. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{\begin{tabular}{c} **Specimen** \\ **Name** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} **Control** \\ **Displacement** \\ **(mm)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} \(E_{D,ave}(i)\) \\ **(kN\(\cdot\)m)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} \(E_{So}(i)\) \\ **(kN\(\cdot\)m)** \\ \end{tabular} } & \multirow{2}{*}{\begin{tabular}{c} \(\beta_{eq}\) \\ **(kN\(\cdot\)m)** \\ \end{tabular} } & \multirow{2}{*}{\
\begin{tabular}{c} \(\beta_{eq}\) \\ **(kN\(\cdot\)m)** \\ \end{tabular} } & \multirow{2}{*}{
\begin{tabular}{c} \(\beta_{eq}\) \\ **(kN\(\cdot\)m)** \\ \end{tabular} } \\ \hline \multirow{3}{*}{NBSD-1} & 11 & 2.79 & 0.69 & 0.32 & \multirow{3}{*}{0.36} & \multirow{3}{*}{119.5} \\ \cline{2-2} \cline{5-6}  & 22 & 8.43 & 1.6 & 0.42 & & \\ \cline{2-2} \cline{5-6}  & 33 & 17.01 & 3.54 & 0.38 & & \\ \hline \multirow{3}{*}{NBSD-2} & 11 & 2.67 & 0.71 & 0.3 & \multirow{3}{*}{0.34} & \multirow{3}{*}{116.1} \\ \cline{2-2} \cline{5-6}  & 22 & 8.19 & 1.96 & 0.34 & & \\ \cline{2-2} \cline{5-6}  & 33 & 16.54 & 3.48 & 0.38 & & \\ \hline \hline \end{tabular} \(E_{D,ave}(i)\): average energy dissipation for one cycle of control displacement, \(E_{So}(i)\): elastic potential energy, \(\beta_{eq}\): equivalent damping ratio, \(\beta_{eq,ave}\): Average equivalent damping ratio, and \(E_{D,D,del}(i)\): total cumulative energy dissipation (\(i\): 11, 22, 33 mm).  
\end{table} 
Table 4: Equivalent damping ratios and cumulative energy dissipation of the NBSD-based seismic control system. Figure 8: Concepts of effective stiffness, elastic potential energy, and energy dissipation in seismic control systems: (**a**) effective stiffness and (**b**) elastic potential energy and cumulative energy dissipation. (3) Performance criteria for the NBSD-based seismic control system  
As mentioned above, cyclic loading tests were conducted according to the test methods using displacement-controlled seismic control systems provided in \"17.6 Tests of Dampers of KDS 41 17 00: 2019 [5].\" Based on the test results, the performance of the seismic control system was evaluated against the criteria shown in Table 5[5]. Both NBSD-1 and NBSD-2 developed in the present study were tested for performance conformance, and the results are presented in Tables 6 and 7, respectively. All conformance tests were conducted while the maximum displacement of 33 mm was applied. The results showed that the NBSD specimens met the performance requirements for displacement-controlled seismic control systems.