Temperature Effect on Mechanical Properties and Damage Identification of Concrete Structure

Table 7

Change rate of the first order natural frequency (%).

Damage severity (%)	Temperature (°C)
	−20	0	20	40	60	Range caused by temperature
0	9.429	4.395	3.069	0.000	−3.288	12.717
10	6.251	2.521	−2.230	−4.349	−6.468	12.719
20	−0.594	−3.818	−5.144	−6.203	−9.385	8.791
30	−3.820	−5.939	−7.795	−10.978	−13.889	10.069
40	−5.939	−8.099	−10.422	−12.685	−15.346	9.407
Range caused by damage	15.368	12.494	13.491	12.685	12.058