## 5 Strength Evaluation  
### Theoretical Strengths  
The chord face plastification strength \(V_{CP}\) of the unstiffened and stiffened plate-to-RHS K-connections was evaluated using the equations discussed in the previous Section 2. For the unstiffened connection N00-150, \(V_{CP}\) was computed by Equations (1) and (2) for the T- or Y-connections where one branch member is joined. Since both the tensile and compressive branch members were connected to one longitudinal plate, the plate length \(l_{p}\) in Equations (1) and (2) was replaced by an effective length 0.5\(l_{p}\) (=350 mm). For the stiffened connections S15-150 and S25-200, \(N_{CP}\) was computed by Equations (7) and (9), and \(V_{CP}\) was then determined from Equation (4). As shown in Table 5, the \(Q_{f}\) values (i.e., chord member stress function) were different depending on the direction of loading, and thus, the values of \(V_{CP}\) for the positive and negative loadings (i.e., under chord compression and tension, respectively) were separately computed. In the computation of \(Q_{f}\), the axial loads of the chord member (=\(N_{u}\)) were approximated as the maximum loads \(V_{u}\) by the test and the moment was neglected (\(M_{u}\) = 0). The theoretical strengths in Table 5 were computed based on the actual material strengths in Table 4.  
Table 5 also presents the slip and hole-bearing resistances in the bolted joint of branch members, \(V_{slip}\) and \(V_{bearing}\), respectively. \(V_{slip}\) (=190 kN) and \(V_{bearing}\) (=533 kN) were computed by Equations (10)-(13). In the computation of \(V_{slip}\), the preload of the bolts was taken as \(T_{o}\) =204 kN measured by the torque wrench. Note that, for the stiffened truss connections, \(V_{slip}\) (=190 kN) was the smallest and thus the governing limit state was the slip at the bolted joint between the longitudinal plate and branch member. However, since bearing action was activated as the body of the bolts was in contact with  
\begin{table}
\begin{tabular}{l l l l l l l} \hline \hline \multirow{3}{*}{**Specimen**} & \multicolumn{3}{l}{**Chord Face Plastification Strength \(V_{CP}\) (kN) 1**} & \multicolumn{3}{l}{**Bolted Connection Strength (kN)**} \\ \cline{2-7}  & **AISC 360-10** & & **CIDECT Design Guide 3** & **Slip** & **Post-slip ultimate** \\ \cline{2-7}  & **Positive 2** & **Negative 2** & **Positive 2** & **Negative 2** & **\(V_{slip}\)** & _VSB (=\(V_{slip}\) + \(V_{bearing}\))_ \\ \hline N00-150 & +154 & \(-\)149 & +135 & \(-\)132 & 190 & 723 (=190 + 533) \\ \hline S15-150 & +525 & \(-\)525 & +402 & \(-\)394 & 190 & 723 (=190 + 533) \\ \hline S25-200 1 & +644 & \(-\)644 & +479 & \(-\)463 & 190 & 723 (=190 + 533) \\ \hline \hline \end{tabular}  
* For N00-150, \(N_{CP}\) was computed by Equations (1) and (2), applying an effective length 0.5\(l_{p}\) instead of \(l_{p}\). For S15-150 and S25-200, Equations (7) and (9) were used. \(V_{CP}\) was then computed by Equation (4). 2 The chord member was in compression and tension under positive and negative loadings, respectively.  
\end{table}
Table 5: Theoretical strengths of plate-to-RHS truss connections.  
the edge of the hole after slip, the ultimate resistance of the bolted joint was greater. Such post-slip ultimate strength was estimated by adding \(V_{slip}\) and \(V_{bearing}\); \(V_{SB}=V_{slip}+V_{barring}\) (=723 kN).