Experimental analysis of a mechanical shear connector in concrete filled steel tube column

This work includes an analytical and experimental study of the structural behavior of shear connectors in composite columns, composed of concrete-filled circular hollow section. For this study was adopted a structural bolt like a shear connector in order to verify the validity of the analytical expressions in ABNT NBR 16239: 2014 [1]. Was carried out a series of push-out tests, fixing the outer diameter of the hollow section and varying the thickness, the bolt diameter, the strength of concrete and the hole dimension. Analysis of the results shows that is possible to use this type of shear connector. The Brazilian prescriptions results are conservative and may be adjusted to provide strength capacity value closest to the experiment.

Keywords:
concrete filled steel tube; circular hollow section; push-out test

Authorship

J. G. R. NETO

Pontifical Catholic University of Goiás, School of Civil Engineering, Goiânia, GO, Brasil. julianogeraldo.eng@gmail.comPontifical Catholic University of GoiásBrazilGoiânia, GO, BrazilPontifical Catholic University of Goiás, School of Civil Engineering, Goiânia, GO, Brasil. julianogeraldo.eng@gmail.com

A. M. SARMANHO

Federal University of Ouro Preto, Departament of Civil Engineering, Ouro Preto, MG, Brasil. arlene.sarmanho@gmail.comFederal University of Ouro PretoBrazilOuro Preto, MG, BrazilFederal University of Ouro Preto, Departament of Civil Engineering, Ouro Preto, MG, Brasil. arlene.sarmanho@gmail.com

SCIMAGO INSTITUTIONS RANKINGS

Figures | Tables | Formulas

Figures (21)
Tables (9)
Formulas (5)

Name	Ø x t Tube	Ø Bolt	Ø of Hole	Kind of hole	fcm
Name	(mm)	(pol.)	(pol.)	Kind of hole	(MPa)
C1-15,1-3/4-SF-21,7	219x15,1	3/4	3/4	SF	21,7
C2-15,1-3/4-SF-22,9	219x15,1	3/4	3/4	SF	22,9
C3-15,1-3/4-SF-30,8	219x15,1	3/4	3/4	SF	30,8
C4-15,1-3/4-SF-31,1	219x15,1	3/4	3/4	SF	31,1
C5-15,1-3/4-CF-31,1	219x15,1	3/4	13/16	CF	31,1
C6-15,1-3/4-CF-22,9	219x15,1	3/4	13/16	CF	22,9
C7-15,1-1/2-SF-26,0	219x15,1	1/2	1/2	SF	26,0
C8-15,1-1/2-SF-24,4	219x15,1	1/2	1/2	SF	24,4
C9-15,1-1/2-CF-22,7	219x15,1	1/2	9/16	CF	22,7
C10-8,2-3/4-SF-21,7	219x8,2	3/4	3/4	SF	21,7
C11-8,2-3/4-CF-21,6	219x8,2	3/4	13/16	CF	21,6
C12-8,2-3/4-CF-22,7	219x8,2	3/4	13/16	CF	22,7
C13-8,2-1/2-SF-21,7	219x8,2	1/2	1/2	SF	21,7
C14-8,2-1/2-CF-21,6	219x8,2	1/2	9/16	CF	21,6
C15-8,2-1/2-CF-21,6	219x8,2	1/2	9/16	CF	21,6

Name	Ø x t Tube(mm)	Ø Bolt(pol.)	fcm(MPa)
C16-15,1-SC-25,2	219x15,1	SC	25,2
C17-15,1-SC-25,2	219x15,1	SC	25,2
C18-8,2-SC-25,2	219x8,2	SC	25,2
C19-8,2-SC-25,2	219x8,2	SC	25,2

Ø x t Tube	f_y	f_u	Elongation (ΔL)
(mm)	(MPa)	(MPa)	(%)
219x8,2	385	582	33
219x15,1	384	598	41

Kind	Extensometer	Number	Models
1	Linear extensometer	5	C3,C4, C5 (serie A)
2	2 lines of rosettes de 90°	16	C13 (serie A)
3	1 lines of rosettes de 90°	8	C1,C10,C12,C15,C9 (serie A)
4	1 lines of rosettes de 90°	5	C16,C18 (serie B)

Model	Applied force (KN)	Concrete		Steel		Relarion
	Applied force (KN)	Compression resistence (kN)Af_c	Confinement resistence (kN)Aσ_c,Rd	Yield resistence (kN)Af_y	Ultimate resistence(kN)Af_u	(1)/(2)	(1)/(3)	(1)/(4)	(1)/(5)
	(1)	(2)	(3)	(4)	(5)	(1)/(2)	(1)/(3)	(1)/(4)	(1)/(5)
C1	1.940	608	868	3.714	5.629	3,19	2,24	0,52	0,34
C2	1.800	641	915	3.714	5.629	2,81	1,97	0,48	0,32
C3	1.894	862	1.232	3.714	5.629	2,20	1,54	0,51	0,34
C4	1.900	871	1.243	3.714	5.629	2,18	1,53	0,51	0,34
C5	1.889	871	1.243	3.714	5.629	2,17	1,52	0,51	0,34
C6	1.813	641	915	3.714	5.629	2,83	1,98	0,49	0,32
C7	1.375	728	1.039	3.714	5.629	1,89	1,32	0,37	0,24
C8	1.190	683	977	3.714	5.629	1,74	1,22	0,32	0,21
C9	1.925	636	907	3.714	5.629	3,03	2,12	0,52	0,34
C10	1.451	700	999	2.091	3.247	2,07	1,45	0,69	0,45
C12	1.699	732	1.045	2.091	3.247	2,32	1,63	0,81	0,52
C13	1.334	700	999	2.091	3.247	1,91	1,33	0,64	0,41
C15	1.171	696	996	2.091	3.247	1,68	1,18	0,56	0,36

Model	Concrete verification(kN)		Shear of bolt (kN)	Crushing the tube wall(kN)	V_{Rd, teo} (kN)	V_Rd,exp (kN)	V_Rd,exp V_{Rd, teo}


C1-15.1-3/4-SF-21,7	51	56	76	413	51	163	3,18
C2-15.1-3/4-SF-22,9	54	59	76	413	54	191	3,55
C3-15.1-3/4-SF-30,8	73	80	76	413	73	124	1,71
C4-15.1-3/4-SF-31,1	73	81	76	413	73	133	1,81
C5-15.1-3/4-CF-31,1	73	81	76	413	73	140	1,91
C6-15.1-3/4-CF-22,9	54	59	76	413	54	171	3,18
C7-15.1-1/2-SF-26,0	41	30	33	275	30	125	4,17
C8-15.1-1/2-SF-24,4	38	28	33	275	28	133	4,72
C9-15.1-1/2-CF-22,7	36	26	33	275	26	160	6,11
C10-8.2-3/4-SF-21,7	55	56	76	218	55	95	1,72
C12-8.2-3/4-CF-22,7	58	59	76	218	58	98	1,69
C13-8.2-1/2-SF-21,7	37	25	33	146	25	105	4,20
C15-8.2-1/2-CF-21,6	37	25	33	146	25	88	3,51

Model	Applied load (kN)	δ (mm)
C16-15,1-SC-25,2	823	0,86
C17-15,1-SC-25,2	974	1,10
C18-8,2-SC-25,2	266	0,32
C19-8,2-SC-25,2	185	0,28

Model	Applied load (kN)	τ_exp (MPa)	f_2σ (MPa)	τ_Rd (MPa)	τ_exp/f_2σ	τ_exp/τ_Rd
C16-15,1-SC-25,2	823	1,46	1,73	0,55	0,84	2,66
C17-15,1-SC-25,2	974	1,73	1,73	0,55	1,00	3,14
C18-8,2-SC-25,2	266	0,44	1,41	0,55	0,31	0,80
C19-8,2-SC-25,2	185	0,31	1,41	0,55	0,22	0,56

BoltØ x l	f_ub(MPa)
1/2"x4"	660
3/4"x4"	665