Comparative Investigation on Torsional Behaviour of RC Beam Strengthened with CFRP Fabric Wrapping and Near-Surface Mounted (NSM) Steel Bar

Table 6

Experimental results of the tested beams.

Beam code	Str. Tech.	MPa	Tcr kN·m	%Incr.Tcr	Tu kN·m	%Incr.Tu	θu deg./m	%Inc. θu
Control	Un-str.	48	4.50	—	10.75	0	4.77	0
100C100	CFRP sheet		N.A	—	25.15	134	10.49	120
100C150			7.75	72	21.85	103	10.39	118
100C200			7.00	56	19.88	85	9.17	92
NSM100	NSM steel bar		8.50	89	15.50	44	3.97	−17
NSM150			8.00	78	14.75	37	3.64	−24
NSM200			7.00	56	14.35	33	3.47	−27

Str. Tech.: strengthening technique; %Incr.T_cr: increase of cracking torque in percentage; %Incr.T_u: increase of ultimate torque in percentage; %Incr. θ_u: increase of ultimate twist angle in percentage; Un-str.: Unstrengthened.