Making the construction procedures of short span bridges more rational and economical, the slab bridge composed of steel square tubes was proposed. Ensuring the durability of the bridge, fatigue life evaluation was required. In order to investigate the fatigue life of steel square tubes composing the proposed slab bridge, fatigue tests on steel square tubes were conducted. As a result of these tests, it is confirmed that the fatigue strength of steel square tube composing the proposed slab bridge can be evaluated as the Category C of JSSC fatigue design guideline.
