Blanca Arenas Ramírez

1. The influence of heavy goods vehicle traffic on accidents: the analysis in two transportation corridors Blanca Arenas Ramírez

2. Contens Methodology developed to analyze the influence of traffic conditions: volume and traffic composition, on accidents on different types of interurban roads belonging to the Spanish network, by applying negative binomial models. ۞INTERURBAN ROADS OF RCE NETWORK ۞HEAVY GOODS VEHICLES TRAFFIC EFFECTS ۞SPANISH FREIGHT TRANSPORTATION CORRIDORS

3. Data Road types: • AP: toll motorways • AV: roads with limited access and free motorways • C: single carriageway roads • DC: two undivided dual carriageways

4. Data

5. Data

6. Data

7. Data • Increasing trend in goods traffic, • Increase in mobility on the Spanish network and, • Greater severity of accidents with the involvement of HGV on interurban roads

8. Methodology • Expression for the regression model: • General expression for the estimated model: : Accident rate : Exposure

9. Methodology • The most general expression for the predicted number of accident:

10. Results • Expressions of the accident rates by road types (i) and segment (j) are calculated to be:

11. Results Accident rates λh by road type

12. Scenarios Scenarios of AADTHGV changes with and without any change to total vehicular traffic intensity (AADT):

13. Freight transportation corridor: MB

14. Freight transportation corridor: SB

15. Freight transportation corridors

16. Freight transportation corridors

17. HGVs subtructionscenarios in MB corridor • Variation in vk exposure and the number of accidents in the Aa, Ab and Ac scenarios, over the MB corridor:

18. HGVs subtructionscenarios in MB corridor • Variation in vk exposure and the number of accidents in the Ba, Bb and Bc scenarios, over the MB corridor:

19. HGVs subtructionscenarios in SB corridor • Variation in vk exposure and the number of accidents in the Aa, Ab and Ac scenarios, over the SB corridor:

20. HGVs subtructionscenarios in SB corridor • Variation in vk exposure and the number of accidents in the Ba, Bb and Bc scenarios, over the SB corridor:

21. Results in MB corridor by HGVs subtruction

22. Results in MB corridor by HGVs subtruction

23. Results in SB corridor by HGVs subtruction

24. Results in SB corridor by HGVs subtruction

25. CONCLUSIONS • For all the scenarios taken into account, on the high capacity roads (AP, AV) there is a significant reduction in the total number of accidents, which varies between 16.38% for the Ba scenario of the MB corridor and 7.35% for the Bc scenario of the SB corridor. • Likewise, on the sections of single carriageway roads (C) there are significant increases in the total number of traffic accidents, whose maximum and minimum values are: • 28.06% for the Bc scenario on the MB corridor and 6.52% for the Aa scenario on the SB corridor.

26. CONCLUSIONS • In all cases a reduction in the total number of accidents would occur as a result in the drop in the number of heavy goods transport vehicles (%HGVs). This drop varies between 46 for the SB corridor Bc scenario and 141 for the MB corridor Aa scenario. • In all cases, the higher the traffic intensity (AADT), as a result of the induction of other vehicular traffic, the higher the number of accidents is, due to the increase in exposure. This effect is greater on single carriageway road segments compared to high capacity roads

27. CONCLUSIONS • The model shows itself to be a useful tool for evaluating the effects of modal transfer policies between road and rail or other forms of transport. • This type of analysis provides objective elements for evaluating policies that encourage modal shift and road safety enhancement.