Abstract
Although a trailer is not a self-propelled vehicle, it is treated like a truck or passenger car under the Road Transport Vehicle Act in Japan. So by law, a trailer is required to have a vehicle registration, along with periodic and daily inspections. Trailers usually have a larger body size and loading capacity than general cargo trucks. Due to these characteristics, trailer frames and components often develop damage related to metal fatigue which is caused by the stresses produced by both forward and turning motions. When trailers are used for more than 10 years, deterioration (corrosion and rust) can worsen, and if not maintained correctly, this can lead to serious accidents. In order to secure trailer transportation safety, this paper recommends that special maintenance methods should be used for trailers that have been in use for longer than 10 years.
