## 4 Results and Discussion
When the height exceeds 1.5 times of the wind barrier's height (\(y/H_{b}>1.5\)), the deceleration effect of the wind barrier on the airflow disappears, and the average wind speed has exceeded the incoming flow. It can be seen from Figure 7a that the closer to the wind barrier on the windward side of the bridge, the higher the average wind speed, which changes more sharply in the vertical direction. As shown in Figure 7b-f, the greater the increase of the distance from the wind barrier on the windward side of the bridge, the stronger the inhibitory effect of the wind barrier on the airflow. The airflow tends to be stable and the average wind speed decreases, which is consistent with the previous results from [PERSON] et al. [23]. Compared with the three other curved wind barriers, the average wind speed at different positions behind the C4 wind barrier are larger. This indicates that the curvature of the curved wind barrier exceeds a certain value, and the deceleration effect on the airflow will be significantly weakened. Figure 8 shows the pressure cloud diagram of the bridge without and with wind barriers. As shown in Figure 8a, the airflow separates at the wind fairing and flows to the upper and lower surfaces of the bridge when no wind barrier is installed on the bridge. The upward airflow forms a small range of high wind pressure area near the wind fairing. Except for the negative pressure area around the leading point of the windward side, the wind pressure on the upper surface of the whole bridge deck is close to 0 Pa. The pressure of the entire region under the bridge is negative due to the downward airflow and forms high negative pressure areas at two inflection points on the lower surface of bridge. After the curved wind barrier is installed on the bridge deck, as present in Figure 8b-e, the high wind pressure area near the wind fairing spreads to the windward side of the wind barrier. Due to the blocking effect of the wind barrier, the pressure of whole area above the bridge deck becomes negative. A high negative pressure area is also formed under the wind fairing, and the range and negative pressure at two inflection points on the lower surface of the bridge increase. The curvature of the wind barrier has great influence on the wind pressure distribution of the bridge. With the increase of the curvature of the wind barrier, the high-pressure region and pressure value between the wind fairing and the wind barrier on the windward side of the bridge decrease, and the high negative pressure area at the inflection point on the lower surface of the bridge also decreases slightly. Figure 7: Mean velocity profiles at different positions behind the curved wind barrier on the windward side of the bridge: (**a**) X = \(H_{b}\), (**b**) X = 1.5\(H_{b}\), (**c**) X = 2\(H_{b}\), (**d**) X = 25\(H_{b}\), (**e**) X = 3\(H_{b}\), (**f**) X = 35\(H_{b}\). Figure 9 presents the variations of drag and lift coefficients of the bridge without and with wind barriers. The wind load on the wind barrier will transmit to bridge, and the aerodynamic coefficients of the bridge increase. It can be seen from Figure 9a,b that the aerodynamic coefficients of bridge decreases with the increase of the wind barrier's curvature, especially drag coefficient \(C_{D}\). The \(C_{D}\) value of the bridge without a wind barrier is 0.457; after C1, C2, C3, and C4 wind barriers are installed on the bridge, the \(C_{D}\) values of the bridge are 0.761, 0.668, 0.626, and 0.601, increasing 66.5%, 46.2%, 36.9%, and 31.5%, respectively. This indicates that the smaller the curvature of the wind barrier, the stronger the blocking effect on the airflow, and the greater the wind load on the bridge. Compared with the other three curved wind barriers, the installation of the C1 wind barrier significantly increases the drag and lift coefficients of the bridge, which has a more negative influence on the safety of the bridge.