# Experimental and Numerical Studies on the Structural Performance of a Double Composite Wall
## 2 Experimental Program  
### Test Specimens  
Table 1 and Figure 3 show the section details and material properties of the DCW specimens. All the test specimens were fabricated at a 1/2 actual scale, which was determined based on the limitation of experimental testing facilities for this study, and the PC panel had a width (\(b\)) of 1190 mm and a length (\(L\)) of 7300 mm. Inside the PC flange, 13 reinforcing bars with a diameter of 19 mm were placed, and distribution bars with a diameter of 10 mm were arranged at intervals of 150 mm. In addition, stirrups were laid inside the shear keys to control the localized cracks that may occur during the lifting and assembly of PC panels. In the flexural specimen DCW-F and the shear specimens DCW-SB(1) and (2), bolts were used to assemble the PC panels at the both ends and at the center of the member. On the other hand, no bolts were placed in the shear span of the DCW-SN specimen. Note that the shear contribution of bolts used to assemble the PC panels can be obtained by comparing the shear strength of the DCW-SN specimen and that of the DCW-SB specimens. For the DCW-F specimen, 10 mm-diameter stirrups were placed in the hollow part at 150 mm intervals to prevent shear failure during the experiment. The yield strengths of the D19 and D10 bars (\(f_{y}\) and \(f_{vy}\)) used in the specimen fabrication were 625 and 591 MPa, respectively, and the yield strength of the bolt (\(f_{yb}\)) used for assembling the PC panels was 476 MPa. \begin{table}
\begin{tabular}{c c c c c c c c c c c c c} \hline \hline \multirow{2}{*}{**Specimen**} & \(h\) & \(t_{f}\) & \(d_{s}\) & \(b\) & \(b_{w}\) & \(A_{s}\) & \(A_{wp}\) & \(A_{bv}\) & \(f_{vy}\) & \(f_{vb}\) & \(f^{\prime}_{c,PC}\) & \(f^{\prime}_{e,CIP}\) \\ \cline{2-13}  & **mm** & **mm** & **mm** & **mm** & **mm** & **mm\({}^{2}\)** & **mm\({}^{2}\)** & **mm\({}^{2}\)** & **MPa** & **MPa** & **MPa** & **MPa** & **MPa** \\ \hline DCW-F1 & 600 & 80 & 560 & 1190 & 120 & 3724 & 143 & 628 & 625 & 591 & 476 & 42.6 & 23.5 \\ DCW-SN & 600 & 80 & 560 & 1190 & 120 & 3724 & - & - & 625 & 591 & 476 & 40.2 & 23.5 \\ DCW-SB(1) & 600 & 80 & 560 & 1190 & 120 & 3724 & - & 628 & 625 & 591 & 476 & 40.4 & 23.5 \\ DCW & -SB(2) & 600 & 80 & 560 & 1190 & 120 & 3724 & - & 628 & 625 & 591 & 476 & 40.4 & 23.5 \\ \hline \end{tabular}  
* Notations: \(h\): height of section; \(t_{f}\): thickness of precant concrete (PC) flange; \(d_{s}\): depth of tensile reinforcing bars; \(b\): width of section; \(b_{w}\): width of PC web; \(A_{s}\): amount of tensile reinforcing bars; \(A_{w}\): amount of shear reinforcing bars; \(A_{w}\): sectional area of bolt; \(f_{yz}\): yield strength of tensile reinforcement; \(f_{yy}\): yield strength of shear reinforcement; \(f_{yz}\): yield strength of bolt; \(f^{\prime}_{c,PC}\): compressive strength of precant concrete; \(f^{\prime}_{c,CIP}\): compressive strength of cast-in-place (CIP) concrete.  
\end{table} 
Table 1: Dimensions and material properties of the test specimens. Figure 3: \(Cont\). Figure 4 shows the fabrication process of the DCW specimens. First, concrete was poured and subjected to steam curing for one day, and a 6 mm-deep rough surface treatment was applied on the upper surface of the PC panel in accordance with the ACI 318 code [15]. Figure 3: Section details of test specimens (unit: mm): (**a**) specimen naming; (**b**) DCW-F specimen; (**c**) DCW-SN specimen; (**d**) DCW-SB (1) and (2) specimens. to ensure the composite performance with CIP concrete. After this, the PC panels were assembled using bolts, grout was injected into the bolt holes, and CIP concrete was poured into the hollowed section to complete the specimen fabrication. The specimens were then cured in the atmosphere for 28 days. The concrete compressive strength of the PC panel (\(f^{\prime}_{c,PC}\)) ranged from 40.2 to 42.6 MPa, and that of the CIP concrete (\(f^{\prime}_{c,CIP}\)) was 23.5 MPa. As shown in Figure 5, the DCW-F specimen was subjected to two-point loads with a shear span to depth ratio (\(a/d_{s}\)) of 5.45.