# A Large Bridge Traffic Operation Status Impact Assessment Model Based on AHP-Delphi-SVD Method
## 5 Simulation and Results of Impact of Parameters on Bridge Traffic Operation
### Simulation Results and Analysis  
We simulated three different conditions of road capacity, compared the conditions of good and bad traffic conditions with the conditions of excellent traffic conditions, and added a comparison of adjacent lane changes. Figures 4-7 show the comparison results of the number of vehicles and average speed collected during good traffic conditions with excellent traffic capacity:  
Figure 4: The number of vehicles recorded by sensor 378 when the traffic status is excellent or good.  
It can be clearly seen from Figures 4 and 5 that, when there are slight changes in road and bridge facilities, the number of vehicles passing through the road does not change significantly and the changes are relatively stable. It has had a certain impact on the speed of the vehicle, with some changes occurring, but the changes are not significant, which can ensure the normal passage of the vehicle. From Figures 6 and 7, it can be seen that, when there are slight changes in the highway bridge facilities, they also have a certain impact on adjacent lanes, but the changes are not significant, and vehicles can pass through relatively smoothly.  
In summary, when there are minor changes in bridge facilities, it will not have a significant impact on the driving conditions of vehicles, and they can pass smoothly as a whole. The number of vehicles passing through remains stable, and the speed is also higher than the minimum speed specified for highways (60 km/h).  
Figure 5: The average vehicle speed recorded by sensor 378 when the traffic status is excellent or good.  
Figure 6: The number of vehicles recorded by sensor 379 when the traffic status is excellent or good.  
Figure 7: The average vehicle speed recorded by sensor 379 when the traffic status is excellent or good.  
In summary, when there are significant changes in bridge infrastructure, it has a significant impact on the driving conditions of vehicles. Overall, the traffic efficiency is low, the number of vehicles passing through is small, and it leads to serious congestion in adjacent lanes, resulting in a sharp decrease in vehicle passing speed.  
Looking at the simulation results of the entire traffic model, it can be seen from the data collected by sensor 378 that when there are slight changes in the road and bridge infrastructure, the road capacity will be affected to a certain extent, but the overall impact is not significant and the recovery is relatively fast. When there are significant changes in the infrastructure of roads and bridges, the road capacity will undergo drastic changes, which will have a huge impact on vehicles and traffic, and the recovery of traffic will also be relatively slow.  
According to the data recorded by sensor 379 arranged for adjacent lanes, when there are significant changes in bridge infrastructure, the road capacity of adjacent lanes will also be affected. This conclusion conforms to the general rules of transportation operation and has high reliability and accuracy.