A construction method for a girder in a bridge in which a plurality of piers are installed in an interval in a longitudinal direction of the bridge, a plurality of copings are installed on the piers, and a plurality of girders respectively installed between the piers are installed on the copings. A wrist support panel extends laterally from the bottom of each grip to provide a rest for the blade portion of the gripping hand. The full backup is restored, including the source directory, and a new directory is created to replace the restored directory when the incremental or differential backup is applied to the restored full backup.