# Seismic Upgrade of an Existing Reinforced Concrete Building Using Steel Plate Shear Walls (SPSW)
## 2 Description of the r/c Building  
The r/c building under study is a 3-story building located in Amaliada, Greece, and its design was carried out in 1976 on the basis of the requirements of the 1959 seismic code [1]. A common characteristic of r/c buildings designed by this seismic code is their poor ductile behavior and, in many cases, the scarcity of enough transverse (shear) steel reinforcement for columns. Thus, r/c buildings designed according to [1] cannot conform to ductile seismic requirements [2; 3] unless a case-dependent seismic upgrade strategy is employed. The whole set of architectural plans and formworks was available at the time of this study and it is indicatively shown in Figures 2-4. According to Figures 2 and 3 and more specifically section AA', the building has an asymmetrical floor plan and a total height of 10.65 m. The first storey is 4.15 m high, while the second and third storeys have a height of 3.25 m each.  
The dimensions (in cm) of all beams are 20/50, whereas those of columns are 35/35 for the first storey and 30/30 for the second and third storeys. The longitudinal steel reinforcement of beams and columns is presented in Tables 1 and 2, respectively. It is also noted that the transverse reinforcement is \(\Phi 6/220\) (in mm) for beams and \(\Phi 8/150\) (in mm) for columns. The thickness of the floor slabs is 14 cm. The material properties and the detailing rules of the building align with the seismic provisions of 1959 [1]. More specifically,the grades of concrete and steel reinforcement are C12/15 and S220, respectively. With respect to the loads considered for the design of the building, the dead and live loads on the slabs are 0.8 kN/m\({}^{2}\) and 2.0 kN/m\({}^{2}\), respectively, whereas, for the cantilever slabs, a live load equal to 5.0 kN/m\({}^{2}\) is assumed. The dead loads from infills (9.9 kN/m for the external ones and 5.8 kN/m for the internal ones) are distributed to the beams.  
Figure 3: Front view (**left**) and section (**right**) of the r/c building.  
Figure 2: Layout of the r/c building: first (ground) floor (**left**); second and third floors (**right**).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Beams** & **Span (Bottom)** & **Support 1 (Top)** & **Support II (Top)** \\ \hline B1 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 4\(\updownarrow\)14 + 2\(\updownarrow\)12 \\ B2 & 2\(\updownarrow\)B18 + 2\(\updownarrow\)20 & 1\(\updownarrow\)18 + 1\(\updownarrow\)20 + 4\(\updownarrow\)14 & 1\(\updownarrow\)18 + 1\(\updownarrow\)20 \\ B3 & 4\(\updownarrow\)14 & 2\(\updownarrow\)14 & 2\(\updownarrow\)14 \\ B4 & 4\(\updownarrow\)18 & 2\(\updownarrow\)18 & 2\(\updownarrow\)18 \\ B5 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B6 & 4\(\updownarrow\)12 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B7 & 4\(\updownarrow\)14 & 2\(\updownarrow\)14 & 2\(\updownarrow\)14 + 2\(\updownarrow\)12 \\ B8 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B9 & 4\(\updownarrow\)18 & 2\(\updownarrow\)18 & 2\(\updownarrow\)18 \\ B10 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B11 & 4\(\updownarrow\)14 & 2\(\updownarrow\)14 & 2\(\updownarrow\)14 \\ B12 & 2\(\updownarrow\)18 + 2\(\updownarrow\)20 & 1\(\updownarrow\)12 + 1\(\updownarrow\)20 & 1\(\updownarrow\)18 + 1\(\updownarrow\)20 \\ B13 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B14 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 2\(\updownarrow\)12 \\ B15 & 4\(\updownarrow\)12 & 2\(\updownarrow\)12 & 4\(\updownarrow\)12 \\ B16 & 5\(\updownarrow\)18 & 2\(\updownarrow\)12 + 3\(\updownarrow\)18 & 3\(\updownarrow\)18 \\ \hline \hline \end{tabular}
\end{table}
Table 1: Longitudinal reinforcement of beams.  
Figure 4: Formwork of 1 st floor.