Evaluation Effects of the Short- and Long-Term Freeze-Thaw Exposure on the Axial Behavior of Concrete-Filled Glass Fiber-Reinforced-Polymer Tubes

Table 4

Overall response characteristics for confined concrete (CFFT) cylinders.

Specimen code	Average failure level
	100 F/T cycles				300 F/T cycles
	Load kN	𝑓^′𝑐𝑐 strength (MPa)	Axial strain	Radial strain	Load kN	𝑓^′𝑐𝑐 strength (MPa)	Axial strain	Radial strain
Group 1: room temperature
A-R1	1297.15	71.5	0.028	0.026	1306.6	72.0	0.030	0.022
			0.036	0.028			0.041	0.036
A-R2	1290.1	72.1	0.023	0.030	1288	71.1	0.031	0.025
			0.045	0.037			0.037	0.035
A-R3	1311.3	72.3	0.035	0.027	1216	67	0.033	0.027
			0.036	0.028			0.034	0.029
Average	1299.52	71.6	0.034	0.029	1270.2	70	0.034	0.029
SD	10.8	0.61	0.023	0.017	47.9	2.7	0.003	0.001
Group 2: F/T in salt water
A-S1	1177.41	64.92	0.025	0.023	1136.7	62.7	0.029	0.028
			0.035	0.031			0.024	0.018
A-S2	1303.71	71.88	0.025	0.022	1225.2	67.6	0.034	0.027
			0.042	0.032			0.029	0.027
A-S3	1306.59	72.04	0.030	0.027	1126.3	61.5	0.030	0.022
			0.032	0.037			0.019	0.020
Average	1262.57	69.61	0.031	0.029	1162.7	63.9	0.027	0.024
SD	73.76	4.07	0.007	0.006	54.3	3.2	0.005	0.004

First letter refers to the type of the tube used in this study. Second letter refers to the type of condition (R: room temperature and S: freeze-thaw exposure in salt water). The third is a number referring to the number of specimens.