## 3 Seismic Shaking Table Tests
### Description of Test System and Sensors  
As shown in Figure 5, the nozzle bottom flange is connected to the adapter flange by bolts, and then the adapter flange is installed on the shaking table by the bolted connection. Then, it can be assumed that the bolted connection of the test mockup with the shaking table is strong enough to assure the fixed boundary condition, as intended. In order to apply appropriate seismic inertia load on the nozzle, two added masses are attached to the pipes. These masses, Added Mass-1 and Added Mass-2, are composed of eight and four plates combined by bolts, respectively.  
For the measurement of seismic strain responses, five strain gauges are attached to the nozzle safe end region where the maximum plastic strain responses are expected. They are almost equally spaced in the circumferential direction at the location of the safe-end region, as shown in Figure 6a. Figure 6b shows the pattern of the general-purpose foil strain gauge type used in this test. Table 4 presents the specification of the used strain gauge.  
Figure 4: Mode shapes for test mockup: **(a)** Mode 1 (11.74 Hz); **(b)** Mode 2 (11.99 Hz); **(c)** Mode 3 (25.89 Hz); **(d)** Mode 4 (27.63 Hz); **(e)** Mode 5 (101.61 Hz).  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Item** & **Performance** \\ \hline Max. Loading (kg) & 2000 \\ Table Size (mm) & 209 \(\times\) 2173 \\ Excitation Axes & 6 DOF (Translation 3 axes, Rotational 3 Axes) \\ Max. Displacement (mm) & Hor. (X, Z) = (\(\pm\)125, \(\pm\)140), Ver. (Y) = \(\pm\)110 \\ Max. Accel. for bare table (g) & Hor. (X, Z) = 17, Ver. (Y) = 21 \\ Max. Accel. with max load (g) & Hor. (X, Z) = 4.9, Ver. (Y) = 6.0 \\ Frequency Range (Hz) & 0.8–100 \\ Excitation Mechanism & Electro-hydraulic Servo, 3 Variable Control \\ Control Software & 354.20/MTS \\ \hline \hline \end{tabular}
\end{table}
Table 3: Shaking table performance.  
As shown in Figure 5, three accelerometers are installed at the test system (one on the shaking table and two on the piping system) to measure the seismic acceleration  
\begin{table}
\begin{tabular}{c c} \hline
**Item** & **Specifications** \\ \hline Model Name & KFGS-1-120-D17-11L15M3S (KYOWA) \\ Gauge Length (mm) & 1 \\ Gauge Resistance (\(\Omega\)) & 120 \(\pm\) 0.7\% \\ Gauge Pattern & Triaxial 0\({}^{\circ}\)–45\({}^{\circ}\)–90\({}^{\circ}\) Rosette, Round base \\ Adoptable Thermal Expansion & 11.7 \(\times\) 10\({}^{-6}\)/\({}^{\circ}\)C \\ Applicable Adhesive & CC-33A, EP-340 \\ \hline \end{tabular}
\end{table}
Table 4: Specifications of the used strain gauge.  
Figure 5: Photo of test mockup with sensors on the shaking table.  
Figure 6: Location and pattern of the strain gauges attached on the test mockup: (**a**) photo of attached strain gauge; (**b**) strain gauge rosette pattern.  
responses. Since the seismic inelastic strain responses at the nozzle depend on what the seismic responses are at the piping system, it is important to investigate the acceleration responses. The accelerometer installed on the shaking table is to measure the input seismic motions needed for the inelastic seismic analyses. Table 5 presents the specifications of the used accelerometers.