Mechanical Performance and Stress–Strain Relationships for Grouted Splices Under Tensile and Cyclic Loadings

International Journal of Concrete Structures and Materials

Table 7 Test results for specimens under incremental and repeated tensile loadings.

Specimen no.		Ultimate load P _u (kN)^a		f _u/f _us (%)^{b, c}		Av. bond strength τ _u (MPa)^d		Elongation (mm)		Relative elongation (%)		Failure mode
IT-	RT-	IT-	RT-	IT-	RT-	IT-	RT-	u _IT	u _RT	δ _IT	δ _RT	IT-	RT-
H400D14		88	88	0.87	0.87	–	–	20.6	22.3	7.5	8.1	Bar fracture	Bar fracture
H400D16		126	125	0.91	0.91	–	–	21.5	21.9	7.6	7.7	Bar fracture	Bar fracture
H400D20		187	178	1.04	1.00	26.2	25.0	40.5	21.8	11.0	5.9	Bar pull-out	Bar pull-out
H400D22		229	213	0.89	0.83	27.8	26.9	17.0	14.1	4.5	3.7	Bar pull-out	Bar pull-out
H400D25		303	288	0.94	0.89	30.0	28.6	30.0	23.3	7.1	5.6	Bar pull-out	Bar pull-out
H400D32		463	458	0.98	0.97	26.3	26.0	39.6	32.2	7.5	6.1	Bar pull-out	Bar pull-out
H500D14		104	101	0.91	0.89	–	–	18.7	17.6	6.8	6.4	Bar fracture	Bar fracture
H500D16		136	140	0.88	0.91	–	32.8	14.8	19.7	5.2	6.9	Bar fracture	Bar pull-out
H500D20		222	218	0.92	0.91	31.1	–	28.5	30.6	7.7	8.3	Bar pull-out	Bar fracture
H500D22		249	264	0.87	0.92	31.5	32.1	16.2	29.1	4.3	7.7	Bar pull-out	Bar pull-out
H500D25		320	321	0.89	0.89	31.7	31.9	24.4	21.9	5.8	5.2	Bar pull-out	Bar pull-out
H500D32		549	533	0.90	0.90	32.3	30.3	36.3	27.7	6.8	5.2	Bar pull-out	Bar pull-out
Mean value (coefficient of variation)				0.92 (0.055)	0.91 (0.048)	–	–	–	–	6.8 (0.28)	6.4 (0.22)	–	–

^a P _u denotes ultimate load.
^b f _u = 4P _u/(πd ²).
^c f _us means ultimate strength of reinforcing steel bar.
^d τ _u = P _u/(πdL _i), L _i with i = 1 or 2 means the length of embedded bar that was pulled out. τ _u was unavailable for splices with bar fracture.