Behavior of FRP-Strengthened RC Beams with Large Rectangular Web Openings in Flexure Zones: Experimental and Numerical Study

International Journal of Concrete Structures and Materials

Table 3 Comparison of experimental and FE load-deflection characteristics for test beams.

Beam ID	Results	P_y (kN)	P_u (kN)	Δ_y (mm)	Δ_u (mm)	K_s (kN/mm)	μ_Δ	E_u (kN·m)	Failure mode
BC-N-4PB	EXP	208	239	9.4	83.9	22.1	8.9	17,566	Y-CC
	FE	226	238	9.4	85.7	24.2	9.1	18,208	Y-CC
	EXP/FE	0.92	1.00	1.00	0.98	0.92	0.98	0.96
BC-O1-4PB	EXP	215	244	8.9	34.2	24.2	3.8	6876	Y-CC
	FE	216	231	9.5	35.7	22.8	3.8	7179	Y-CC
	EXP/FE	0.99	1.05	0.94	0.96	1.06	1.02	0.96
BC-N-CPL	EXP	180	217	7.5	76.9	24.0	10.3	15,283	Y-CC
	FE	178	204	7.0	85.0	25.3	12.1	16,358	Y-CC
	EXP/FE	1.01	1.06	1.07	0.90	0.95	0.85	0.93
BC-O1-CPL	EXP	NY	181	NY	7.0	25.8	–	766	SF-TC
	FE	NY	172	NY	7.6	22.7	–	827	SF-TC
	EXP/FE	–	1.05	–	0.92	1.14	–	0.93
BS1-O1-CPL	EXP	NY	193	NY	8.6	22.4	–	1001	DB-SF-TC
	FE	NY	185	NY	9.1	20.3	–	1039	DB-SF-TC
	EXP/FE	–	1.05	–	0.95	1.10	–	0.96
BC-O2-CPL	EXP	NY	106	NY	3.5	30.2	–	181	SF-TC
	FE	NY	96	NY	3.9	25.0	–	211	SF-TC
	EXP/FE	–	1.10	–	0.91	1.21	–	0.86
BS2-O2-CPL	EXP	NY	201	NY	6.4	31.4	–	788	BKL-FF-TC
	FE	NY	192	NY	5.7	33.8	–	637	BKL-FF-TC
	EXP/FE	–	1.05	–	1.13	0.93	–	1.24

P_y and Δ_y load and mid-span deflection at yielding of bottom steel rebars, P_u ultimate load, Δ_u mid-span deflection at ultimate state, K_s effective pre-yield stiffness, μ_Δ deflection ductility ratio = Δ_u/Δ_y, E_u energy dissipated at ultimate state, Y-CC bottom steel yielding followed by concrete crushing at mid-span, SF-TC shear failure of top chord, DB-SF-TC FRP debonding followed by shear failure of top chord, BKL-FF-TC out-of-plane buckling of steel plates followed by flexural failure of top chord, EXP experimental, FE finite element, NY no steel yielding.