Abstract
This investigation is carried out to clear the difference of lateral stiffness of rahmen frame due to various methods for elastic rotation stiffness of steel exposed-type column base . At first, a new formula for elastic rotation stiffness of steel exposed-type column base considered column axial force and concrere stiffness under base-plate is suggested. It is compared and discussed that lateral stiffness of rahmen frame by nonlinear elastic analysis using the suggested formula compared with the result by conventional elastic analysis using the formula by Architectural Institute of Japan.
