Estimation of Dynamic Characteristics for Steel Frame Membrane Structure

Changes in dynamic characteristics of a steel frame membrane structure were estimated during construction. Effects of membrane on the dynamic characteristics, especially on damping coefficients, were clarified from ambient response and free vibration by human excitation. It was quantified that membrane raised damping coefficients by an average of 2 %. Increase of damping coefficients after membrane installation, however, depended on the natural frequency. Lower modes tended to gain more additional damping coefficients than higher modes.