A fundamental study on Charpy absorbed energy and hardness characteristics of electric resistance welded steel pipes applied to bridge piers

Abstract A multipile‐type frame roadway structure made of compact members is considered to be an effective structure for road construction in mountainous areas. When considering construction in areas with narrow spaces, medium‐diameter steel pipes are a desirable option for the columns of pier structures. Medium‐diameter steel pipes can be mass‐produced in factories as manufactured pipes, and if applied to bridge piers, reductions in construction costs can be expected. On the other hand, electric resistance welded (ERW) steel pipes are commonly used as structural members, but research on the toughness of the steel pipes, which is important for use as bridge piers, is still insufficient. Therefore, in this study, the ERW steel pipes were improved to ensure the Charpy absorbed energy of the 27 J or more for SM490B and the 47 J or more for SM490C at the test temperature of 0 °C, similar to the steel plates used in general steel bridge piers. Charpy impact tests were conducted using this improved ERW pipes to grasp the Charpy absorbed energy characteristics.