Examination of the temperature dependency of natural frequencies of buildings using long-term ambient noise
As a widely used structural health monitoring method,the decrease of natural frequencies is an important evidence of the existence of structural damages because it relates to the degradation of structural stiffness.However,because of the property of materials changes with the temperature,the natural frequency also fluctuates.In order to make a reliable damage determination,the temperature dependency of natural frequency should be examined.Its effect should be excluded when evaluate the decrease of natural frequency.In this study,we examine the temperature dependency of a reinforced concrete(RC)and a steel(S)building using one-year continuous ambient noise.Firstly,the seasonal variation of the fundamental frequency is examined based on the change tendency of the daily average of temperature and the hourly fundamental frequency.We found that,generally,the fundamental frequency is increased with the rising of temperature for both the RC building and the S building,and vice versa.However,temperature dependency of the frequency is more obvious for the RC building than the S building.Secondly,the temperature dependency is studied quantitatively using the linear regression between the monthly average of temperature and that of the fundamental frequency.Based on the slope of the regression lines,the temperature dependency of the RC building is larger than that of the S building.The amplitude dependency of the fundamental frequency for earthquake responses is also studied calibrating the effect of the temperature dependency using the proposed regression lines.
Temperature dependency natural frequency amplitude dependency long-term ambient noise reinforced concrete building steel building
X.Wang T.Hatakeyama M.Motosaka S.Ohno
Assistant Prof.,Department of Architecture and Building Science,Tohoku University,Sendai,Japan Graduate student,Graduate School of Engineering,Tohoku University,Sendai,Japan International Research Institute of Disaster Science,Tohoku University,Sendai,Japan
国际会议
The 7th World Conference on Structural Control and Monitoring(7WCSCM)(第七届结构控制与监测世界大会)
青岛
英文
2552-2558
2018-07-22（万方平台首次上网日期，不代表论文的发表时间）