Cause analysis of road freight accidents based on the CAST-Accimap method

The existing theory of systematic accident analysis is rarely used in traffic accident causation analysis. To reduce the occurrence of road freight accidents, a CAST-Accimap accident causation analysis method is proposed in this paper to analyse 17 significant freight accidents. Initially, the CAST (Causal Analysis based on System Theory) method was applied to analyse vehicle systems and road environmental factors, which served as inputs for the equipment and environmental level in the Accimap model. Subsequently, the Accimap (Accident map) method was employed to analyse the causes of highway freight accidents and their causal relationships across various levels, leading to the construction of an accident network. The Actormap method was also utilised to statistically analyse the accident participants. Further, social network analysis theory was applied to quantitatively assess the accident network, pinpointing the key factors influencing accident occurrence. In the Actormap analysis, the involvement of government policies and budgets, regulatory agencies and associations, and corporate management in technology and operations accounts for 55% of the participants in accidents. Meanwhile, in the Accimap analysis, causes unrelated to the accident process and the equipment environment constitute approximately 45%.The results demonstrate that higher-level elements such as enterprises, regulatory departments, and governments significantly influence road environments and the actions and decisions of drivers during accidents. These findings assist traffic management authorities in making informed safety decisions to prevent highway freight accidents.