Structural design and evaluation require information on future maximum loads and load effects to cover the intended life span of the structure.For civil structures,such as bridges and buildings,the intended life spans can be relatively long compared with available measured data for these loads.Examples of the load include and not limited to wind load,earthquake load,flood load,truck load,etc.Accordingly,using available short term data to project to the future maximum values has been a critical subject in developing reliable specifications for design and evaluation of these structures.