Application of steel fiber reinforced concrete (SFRC) in beams subjected to shear

Suk, Diego Andrey; Ferrari, Vladimir

Acessibilidade / Reportar erro

Brasil

Español English

sumário « anterior atual seguinte »

Sumário

ARTIGO • Ambient. constr. 24 • 2024 • https://doi.org/10.1590/s1678-86212024000100722 copy

Application of steel fiber reinforced concrete (SFRC) in beams subjected to shear

Authorship SCIMAGO INSTITUTIONS RANKINGS

Abstract

For the understanding of the shear behavior of steel fiber reinforced concrete beams without stirrups (shear reinforcement), beams were experimentally studied employing bending tests. The analyzed parameters were two classes of compressive strength (30 MPa and 45 MPa) and three dosages of fibers (40 kg/m³, 60 kg/m³ and 80 kg/m³), in addition to the reference trace. An analytical comparison of the experimental results with calculation models from normative regulations and scientific papers was studied to predict the failure force of the beams. The results showed gains in the ultimate shear strength provided by steel fibers, evidencing their great potential against shear stress. The failure mode of the beams was not altered for the dosages of fibers and compressive strength classes studied. However, higher load and deformation capacity was evidenced with an increasing number of fibers and f _c . The model from Brazilian regulation NBR 16935 (ABNT, 2021a) showed excellent results in predicting the failure force of the beams in group C30.

Keywords:
Concrete beams; Steel fibers; Shear; Concrete strength

Grupos	CRF	Taxa de fibras	Descrição
1.1	C30-0	0	Concreto referência sem fibras
1.2	C45-0	0	Concreto referência sem fibras
2.1	C30-40	40 kg/m³	Concreto classe C30 com fibras
2.2	C30-60	60 kg/m³
2.3	C30-80	80 kg/m³
3.1 3.2 3.3	C45-40 C45-60 C45-80	40 kg/m³	Concreto classe C45 com fibras
		60 kg/m³
		80 kg/m³

Resistência	Cimento	Areia	Brita 0	Água
30 MPa	1	1,45	2,1	0,50
45 MPa	1	1,44	2,0	0,39

CRF	f_cm (MPa)	S_d (MPa)	Cv (%)	f_ctm,cd (MPa)	S_d (MPa)	Cv (%)	σ_b (MPa)	S_d (MPa)	Cv (%)	Slump (mm)	Aditivo (%)
C30-0	30,74	1,14	3,7	2,94	0,18	6,1	4,37	0,38	8,6	165	0
C30-40	34,05	0,61	1,8	2,49	0,20	8,0	4,17	0,32	7,7	120	0,25
C30-60	31,70	0,81	2,6	2,50	0,21	8,5	4,34	0,43	9,8	175	0,40
C30-80	31,64	1,25	4,0	2,91	0,10	3,6	4,53	0,14	3,1	140	0,40
C45-0	45,46	1,89	4,2	3,34	0,01	0,3	3,72	0,38	10,1	180	0,60
C45-40	43,20	0,59	1,4	3,81	0,31	8,1	4,63	0,14	3,1	120	0,65
C45-60	43,78	0,96	2,2	3,46	0,13	3,8	5,09	0,65	12,8	180	0,67
C45-80	45,25	0,97	2,1	4,76	0,58	12,2	6,12	0,24	3,9	160	0,67

CRF	Força primeira fissura			Força fissura critica			Força de pico
CRF	P_f (kN)	S_d	Cv	P_c (kN)	S_d	Cv	P_u (kN)	S_d	Cv
C30-0	9,58	0,17	1,8%	24,89	0,89	3,6%	25,14	0,78	3,1%
C30-40	9,97	0,45	4,4%	33,98	1,06	3,1%	34,82	0,32	9,0%
C30-60	10,39	0,31	2,9%	34,16	2,03	5,9%	36,85	2,49	6,8%
C30-80	10,54	0,58	5,7%	34,86	1,31	3,7%	38,29	2,94	7,7%
C45-0	11,38	0,24	2,1%	30,08	3,24	10,8%	30,83	2,40	7,8%
C45-40	11,44	0,39	3,3%	39,67	2,27	5,7%	42,16	2,3	5,5%
C45-60	11,51	0,47	4,5%	41,51	2,81	6,8%	45,09	4,84	10,7%
C45-80	11,73	0,47	4,0%	46,82	2,44	5,2%	50,44	3,38	6,7%

CRF	Relação		Força para vão/350			Força para vão/250			P_l,250/P_l,350
CRF	P_c/P_f	P_u/P_c	P_l,350	S_d	C_v	P_l,250	S_d	C_v	P_l,250/P_l,350
C30-0	2,60	1,01	-	-	-	-	-	-	-
C30-40	3,41	1,02	31,27	2,52	8,04%	22,66	0,92	4,08%	0,72
C30-60	3,29	1,08	35,21	3,47	9,86%	27,14	2,69	9,90%	0,77
C30-80	3,31	1,10	36,66	4,02	10,96%	29,12	5,05	17,33%	0,79
C45-0	2,64	1,02	12,58	1,85	14,73%	11,14	1,19	10,66%	0,89
C45-40	3,47	1,06	39,81	3,02	7,58%	23,14	3,96	17,13%	0,58
C45-60	3,61	1,09	41,96	2,58	6,15%	36,89	8,22	22,28%	0,88
C45-80	3,99	1,08	46,63	2,08	4,46%	45,88	6,42	13,99%	0,98

CRF	V_f (%)	F	f_c (MPa)	f_ct,sp (MPa)
C30-40	0,51	0,22	34,05	2,49
C30-60	0,77	0,34	31,70	2,50
C30-80	1,02	0,45	31,64	2,91
C45-40	0,51	0,22	43,20	3,81
C45-60	0,77	0,34	43,78	3,46
C45-80	1,02	0,45	45,25	4,76

CRF	V_u-exp (kN)	Modelos: V_u-teor (kN)
CRF	V_u-exp (kN)	[1]	[2]	[3]	[4]	[5]	[6]	[7]	[8]	[9]	[10]	[11]
C30-40	17,41	20,65 (0,84)	12,05 (1,45)	16,84 (1,03)	18,27 (0,95)	10,97 (1,59)	11,46 (1,52)	13,66 (1,27)	13,31 (1,31)	18,34 (0,95)	17,68 (0,98)	17,44 (1,00)
C30-60	18,42	19,93 (0,92)	14,52 (1,27)	18,71 (0,98)	19,17 (0,96)	13,00 (1,42)	12,47 (1,48)	16,01 (1,15)	13,86 (1,33)	21,06 (0,87)	17,65 (1,04)	18,53 (0,99)
C30-80	19,14	19,91 (0,96)	16,87 (1,13)	20,89 (0,92)	19,80 (0,97)	14,94 (1,28)	13,82 (1,39)	18,22 (1,05)	14,73 (1,30)	24,71 (0,77)	18,29 (1,05)	19,30 (0,99
C45-40	21,08	23,26 (0,91)	15,47 (1,36)	18,31 (1,15)	22,84 (0,92)	13,67 (1,54)	12,90 (1,63)	18,15 (1,16)	14,65 (1,44)	20,66 (1,02)	19,17 (1,10)	17,77 (1,19)
C45-60	22,54	23,42 (0,96)	16,25 (1,39)	20,68 (1,09)	22,49 (1,00)	14,37 (1,57)	14,66 (1,54)	18,30 (1,23)	15,81 (1,43)	24,75 (0,91)	20,30 (1,11)	21,69 (1,04)
C45-80	25,22	23,81 (1,06)	21,67 (1,16)	23,09 (1,09)	26,76 (0,94)	18,74 (1,35)	16,53 (1,53)	24,02 (1,05)	17,08 (1,48)	29,55 (0,85)	20,22 (1,25)	26,38 (0,96)
Média		0,94	1,29	1,04	0,96	1,46	1,52	1,15	1,38	0,90	1,09	1,03
C_V (%)		7,06	9,11	7,33	2,61	7,99	4,74	7,17	5,11	8,79	7,71	7,29

Associação Nacional de Tecnologia do Ambiente Construído - ANTAC Av. Osvaldo Aranha, 93, 3º andar, 90035-190 Porto Alegre/RS Brasil, Tel.: (55 51) 3308-4084, Fax: (55 51) 3308-4054 - Porto Alegre - RS - Brazil
E-mail: ambienteconstruido@ufrgs.br

Acompanhe os números deste periódico no seu leitor de RSS

[1] Diego Andrey Suk Departamento de Engenharia Civil | Universidade Estadual de Maringá | Av. Colombo, 5790, Jardim Universitário | Maringá - PR - Brasil | CEP 87020-900 | Tel.: (44) 99850-3653 | E-mail: diego.a.suk@gmail.com