## 3 Finite Element Model
According to this standard, the thickness of the rubber plate should be 8 mm, and at least two elastomers must be used. Although the thickness of the upper and lower rubber plates is stipulated to be 2.5 mm to prevent delamination, the rubbers were designed to be 8 mm, as it is not expected that delamination would occur because it surrounds the shear key, as shown in Figure 2b, and the thickness of the steel plate was 3 mm. A grout gap occurs as much as the difference between the outer diameter of the MP and the inner diameter of the TP. As mentioned above, the grout thickness was determined according to the international design standard. According to this standard, the standard range of the shear key and TP was determined through the dimensions of the MP, and the general (average) dimensions were used for representativeness of the experiment. Therefore, the grout thickness was 420 mm, and the outer diameter of the TP was determined to be 5500 mm. The generated elements of S-E1 and S-E2 are shown in Figure 3, and, through this, the shape of the elastomeric bearing designed to cover the trapezoidal shear key could be confirmed. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Contents** & **Steel** & **Grout Filler** & **Weld Bead** \\ \hline Compressive strength (MPa) & 250 & 130 & 300 \\ Static modulus of elasticity (GPa) & 200 & 50 & 206 \\ Tensile strength (MPa) & 460 & 7 & 300 \\ Density (kg/m\({}^{3}\)) & 7850 & 2440 & 7850 \\ Poisson’s ratio (-) & 0.30 & 0.19 & 0.30 \\ Applied part & MP, TP, Shear keys & Grout filler & Weld bead \\ References & [30] & [31] & [32] \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Structural material properties of grouted connection. \begin{table}
\begin{tabular}{c c} \hline \hline
**Contents** & **Value** \\ \hline Radius of MP, \(R_{P}\) (mm) & 2250 \\ Thickness of MP, \(t_{P}\) (mm) & 80 \\ Length of MP, \(L_{P}\) (m) & 50.0 \\ Radius of TP, \(R_{TP}\) (mm) & 2750 \\ Thickness of TP, \(R_{TP}\) (mm) & 80 \\ Radius of grout gap, \(R_{g}\) (mm) & 2670 \\ Thickness of grout gap, \(t_{g}\) (mm) & 420 \\ Length of GC, \(L_{g}\) (mm) & 8.0 \\ Height of shear key, \(h\) (mm) & 60 \\ Width of shear key, \(w\) (mm) & 180 \\ Vertical center to center distance between shear keys, \(s\) (mm) & 1000 \\ Number of shear keys, \(n\) (-) & 11 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Dimensions of grouted connection with shear keys. Most of the elements were created as hexahedral elements with 20 nodes (SOLID186) to minimize the number of elements. The element model of the elastomeric bearing had a total thickness of 30 mm. Two steel plates with a thickness of 3 mm were divided into one layer, and three rubber plates with a thickness of 8 mm were divided into two layers. In order to smoothly transfer the initial load to the surrounding components of the elastomeric bearing, it is better to match the nodes of the contact. Increasing the element layer in the thickness direction greatly affects the quality of the mesh, which not only increases the memory of the analysis model, but also has a significant effect on nonlinearity convergence. Therefore, the stress on the elastomeric bearing was not analyzed in this paper because it was modeled with too few element layers in the thickness direction of each plate. Moreover, in order to capture the load concentrated in the grout in contact with the elastomeric bearing, which is a relatively small component of the GC, it was divided into 300 layers  
Figure 3: Cross-section of FE model of (**a**) one pair of shear keys and (**b**) elastomeric bearing. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Material Properties** & **S-E1** & **S-E2** \\ \hline Common name & Neoprene (CR) & Natural rubber (NR) \\ Density (kg/m\({}^{3}\)) & 1265.0 & 949.8 \\ Tensile yield strength (MPa) & 16.97 & 24.25 \\ C10 (Pa) & 210,000 & 160,000 \\ C01 (Pa) & 54,000 & 41,000 \\ d (1/Pa) & 1.2 \(\times\) 10 \({}^{-9}\) & 1.2 \(\times\) 10 \({}^{-9}\) \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Material properties of rubber plates (reconfigured).