PURPOSES :The purpose of this study is to perform a reliability analysis of the proposed wind load combination which governs the design of support structures of subsidiary road facilities, and to evaluate whether the target reliability of the design is satisfied.METHODS :The statistical estimation method is applied and the design period of the support structure is used to obtain the statistical property of the wind load. In addition, the statistical properties of the strength of support structures are obtained from a literature review and simulation study. Actual support structures are designed by the proposed load combination and are used as the examples to examine if the target reliability is obtained.RESULTS :The result of the reliability analysis performed by using the statistical properties of load and resistance for the support structure in this study indicates that the proposed wind load combination satisfied the target reliability index of the design. Also, the convenience of the design is achieved by adopting the same design wind velocity given in the bridge design code by applying the wind velocity ratio defined for the design period of the support structure.CONCLUSIONS :It is presented that the design using the wind load combination proposed in this study achieved the target reliability index and the design wind load for different design periods can be conveniently defined by applying the velocity ratio proposed in this study.