# Force Performance Analysis and Numerical Simulation of Assembled Ribbed-Slab Abutments
## 2 Static Load Test of Assembled Ribbed-Slab Abutment Model
### Shear Test of Assembled Ribbed-Slab Abutment  
In the shear test, the loading point was located at the end of the cantilever, and the loading method used a loading device with a 5000 kN counterweight and 5000 kN jack, which was fixed with the same bending test, as shown in Figure 5.  
Experimental Phenomenon  
The FLP4-1 model initially utilized eight ordinary 4.8-grade M12 bolts (up to 18 were available), and there was no notable issues in the structure during the pre-load period.  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Model Number**} & \multicolumn{2}{c}{**Crack Load**} & \multicolumn{2}{c}{**Local Ultimate Load**} & \multicolumn{2}{c}{**Local Limit Displacement**} \\  & \multicolumn{2}{c}{**(kN)**} & \multicolumn{2}{c}{**(kN)**} & \multicolumn{2}{c}{**(mm)**} \\  & **Actual Measured** & \multicolumn{2}{c}{**Actual Measured**} & \multicolumn{2}{c}{**ARBA/XJ**} & \multicolumn{2}{c}{**Actual Measured**} & \multicolumn{2}{c}{**ARBA/XJ**} \\  & **Value** & & **Value** & & **Value** & **ARBA/XJ** \\ \hline XJ1 & 1200 & 1 & 2350 & 1 & 6.1 & 1 \\ NT2 & 700 & 0.58 & 1500 & 0.6 & 5.1 & 0.84 \\ FLP3 & 800 & 0.67 & 2350 & 1 & 4.9 & 0.49 \\ \hline \hline \end{tabular}
\end{table}
Table 2: The stress performance and comparison of each abutment model.  
Figure 5: Schematic diagram of the shear strength test loading device.  
However, when the load was increased to 150 kN, a small crack appeared near the back wall of the flange. Subsequently, the structure emitted a loud noise, and simultaneously, the bolts were sheared off, which is characterized by brittle failure. The test was halted upon reaching a load of 300 kN. The primary damage sustained in this test was bolt damage, with five of them being broken, as illustrated in Figure 6. Remarkably, no damage was observed to the overall concrete structure or the flange itself upon closely examining the structure.  
For the FLP4-2, all the bolts were removed, and they were replaced with eight M12 high-strength 8.8-graded bolts (positioned in the same locations) to restart the test. As the load increased to 200 kN, the cantilever end of the flange near the joints of the cracks exhibited gradually expanded and downward development. Upon reaching a load of 450 kN, the cantilever end of the flange above the joints of the concrete also cracked, leading to the detachment of the flange from the concrete connection. Consequently, the jack could no longer continue to apply load, and the test was terminated. At this point, the structure of the cantilever end of the flange and the concrete connection were detached, as shown in Figure 7, while the bolt in the flange remained damaged. The primary damage in this test was the failure of the connection between the flange and concrete.  
Longitudinal shear test studies have demonstrated that the shear capacity of the flanged ARBA depends primarily on the shear performance of the bolts.  
When evaluating the performance of the ARBA with the two connection methods, it is evident that the ARBA with flange connection can easily attain performance \"equivalent to that of cast-in-place.\" In this case, the primary damage of the ARBA model with a flange  
Figure 6: Sheared bolt.  
Figure 7: Flange connection failure diagram.  
connection comprised damage to the bolts and the cracking of the concrete at the joints. However, there was no major damage to the overall structure, providing more favorable conditions for subsequent repair. Therefore, the flange connection was selected for the subsequent optimization design.