## 2 FE Model Validation  
### Test Overview  
The accuracy of the FE model is validated via static load and horizontal impact tests of RC columns in the literature [16]. The dimensions and reinforcement configuration of a generic column specimen are shown in Figure 1. The specimen consisted of a base (900 \(\times\) 900 \(\times\) 300 mm), a column cap (300 \(\times\) 300 \(\times\) 200 mm), and a 1150-mm-high square column with 3 different side lengths (\(w\) = 120/150/180 mm), which correspond to 3 different longitudinal bars (\(\Phi\)8, \(\Phi\)10 and \(\Phi\)12, respectively) with yield strengths of 408.8 MPa, 424.6 MPa and 470.4 MPa, respectively, and ultimate strengths of 541.1 MPa, 642.3 MPa, and 685.7 MPa, respectively. Grade C55 concrete [17] was used to manufacture the specimen with an axial compression ratio of 0.1. A total of 3 150 mm cubes were cured under the same conditions and used in cubic compressive strength tests. The average values of the measured cubic compressive strength \(f_{\text{cu}}\) is 60.39 MPa. The corresponding compressive strengths were computed as \(f_{\text{c}}\) = 0.76\(f_{\text{cu}}\) and the tensile strengths were determined by \(f_{\text{t}}\) = 0.395\(f_{\text{cu}}^{0.55}\)[17]. In addition, 4 vertical through holes, each with a diameter of 80 mm, were reserved in the base to attach the specimen to the support of the test machine. To apply axial compression through external prestressing, 2 PVC pipes, each with a diameter of 20 mm, were embedded in the base. Once the concrete was cast, reserved holes were formed to allow the passage of the prestressed rods.  
Figures 2 and 3 show the setups for the static load test and the horizontal impact load test, respectively. Before the static load test, the base of the specimen was fixed to the rigid floor of the laboratory through two pressure beams and four ground anchor bolts, and the loading end of the MTS servo-hydraulic actuator was fixed to the column cap to apply a lateral pushing force to achieve a monotonic lateral static load. The impact test setup  
Figure 1: Specim dimensions and reinforcement.  
consisted of a drop hammer and a horizontal impact device. The test truck was connected to the drop hammer through steel strands and fixed pulleys and was then dragged by the falling hammer to impact the specimen. During the impact process, piezoelectric and piezoresistive load cells were installed at the front end of the test truck and the cap of the specimen, respectively, in order to synchronously record the impact force.  
The measurement points for the displacement of the specimen were arranged as shown in Figure 4a. A total of 4 displacement meters were placed at a spacing of 400 mm on the back of the specimen. In addition, displacement meters #5 and #6 were attached  
Figure 3: Impacting testing setup: (**a**) sketch of the impact testing system; (**b**) components of the horizontal impact facility; (**c**) photo of the test truck; (**d**) photo of the drop-weight impact facility.  
Figure 2: Static testing setup: (**a**) sketch of test system; (**b**) photo of the loading program.  
at the edge of the base to monitor whether the base underwent relative translation and rotation during the test. The layout of the strain gauge measurement points for rebars is shown in Figure 4b, with strain gauges \(\varepsilon 1\)-\(\varepsilon 4\) on the tensile longitudinal rebars and \(\varepsilon 5\) and \(\varepsilon 6\) on the compressive rebars. All strain gauges were placed in the area below mid-height, which was significantly stressed. To ensure strain data collection, six strain gauges were also placed on the longitudinal rebars at the symmetrical position on the other side.