10:45 〜 12:15
[HCG23-P05] Projections of the Climate Change Effects on the Dynamic Behavior of Bridge Structures in Costa Rica
キーワード:Climate, Frequency, Structures, Temperature, Costa Rica, Bridges
According to the National Meteorological Institute of Costa Rica (IMN), Costa Rica has a tropical climate due to its location between the Tropic of Cancer and Tropic of Capricorn latitudes. The minimum temperature that has been recorded in Costa Rica within a period of 10 years is 16.9°C, while the maximum recorded temperature has been 32.4°C.
Birkel et al. (2021), show significantly increasing temperatures of 2.6°C with a spatial variability of ± 0.4°C until the year 2040 with local differences (higher temperatures projected for the southern Costa Rican Caribbean).
Changes in the dynamic behavior of structures are normally associated with structural damage or degradation; however, this research measures the dynamic effect of temperature in a bridge located in Costa Rica. The influence that the environmental temperature has on the dynamic behavior of the bridge is measured through the variations in the vibration frequencies.
Measurements of the dynamic response have been made at two different points of the bridge (CS & LS). Furthermore, the measurements have been made at multiple times of the day with different temperatures, from 02:00 to 15:00 with temperatures from 18.8°C to 32.3°C, respectively.
The variation rates in the frequencies of the bridge have been determined according to the evolution of the environmental temperature. The first fundamental mode of vibration varied -0.0075 Hz/°C, causing a variation of -6.6% and up to -7.8% for the present time and for the year 2040, respectively. The results show decreasing trends in frequencies (Figure 1), which are consistent with the studies carried out by the Utah State University (Nichols. G, 2017).
These variations caused by temperature changes should be taken into consideration in future structural damage evaluations such as those caused by extreme damage events (earthquakes, impacts, hurricanes).
Birkel et al. (2021), show significantly increasing temperatures of 2.6°C with a spatial variability of ± 0.4°C until the year 2040 with local differences (higher temperatures projected for the southern Costa Rican Caribbean).
Changes in the dynamic behavior of structures are normally associated with structural damage or degradation; however, this research measures the dynamic effect of temperature in a bridge located in Costa Rica. The influence that the environmental temperature has on the dynamic behavior of the bridge is measured through the variations in the vibration frequencies.
Measurements of the dynamic response have been made at two different points of the bridge (CS & LS). Furthermore, the measurements have been made at multiple times of the day with different temperatures, from 02:00 to 15:00 with temperatures from 18.8°C to 32.3°C, respectively.
The variation rates in the frequencies of the bridge have been determined according to the evolution of the environmental temperature. The first fundamental mode of vibration varied -0.0075 Hz/°C, causing a variation of -6.6% and up to -7.8% for the present time and for the year 2040, respectively. The results show decreasing trends in frequencies (Figure 1), which are consistent with the studies carried out by the Utah State University (Nichols. G, 2017).
These variations caused by temperature changes should be taken into consideration in future structural damage evaluations such as those caused by extreme damage events (earthquakes, impacts, hurricanes).