Change of natural frequency of low-rise buildings based on long-term vibration records

This paper aims to describe the changes in the dynamic characteristics of two existing buildings in Miyagi Pref., Japan. One is a reinforced-concrete(RC) structure and the other is steel one. In this study, we found that the natural frequency of the RC structure is more strongly correlated with temperature in comparison with the steel structure. The temperature dependence of the natural frequencies is included in record indicating the amplitude dependence of the building's dynamic characteristics, and corrections with temperature data can deliver more accurate estimations of a building's structural soundness.