A 1/2-in by 2-in rectangular-cross-section 1015 bar carries a static load of 16.5 kip. It is welded to a gusset plate with a 3 8-in fillet weld 2 in long on both sides with an E70XX electrode as depicted in Fig. 9–18. Use the welding code method. (a) Is the weld metal strength satisfactory?(b) Is

Question

A [latex]\frac{1}{2}-in[/latex] by 2-in rectangular-cross-section 1015 bar carries a static load of 16.5 kip.

It is welded to a gusset plate with a [latex]\frac{3}{8}-in[/latex] fillet weld 2 in long on both sides with an E70XX electrode as depicted in Fig. 9–18. Use the welding code method.
(a) Is the weld metal strength satisfactory?
(b) Is the attachment strength satisfactory?

Accepted Answer

(a) From Table 9–6, allowable force per unit length for a [latex]{3}{8}-in[/latex] E70 electrode metal is
5.57 kip/in of weldment; thus[latex]F = 5.57l = 5.57 \left(4 ight) = 22.28 \ kip[/latex]

Table 9–6
Allowable Steady Loads and Minimum Fillet Weld Sizes

Schedule A: Allowoble Load for Various Sixes of Fillet Welds
Strength Level of Weld Metal (EXX)
	60*	70*	80	90*	100	110*	120
Allowable shear stres. on throat. ksi ( I000 psi) of fillec weld or partial penetration groove weld
[latex] au=[/latex]	18.0	21.0	24.0	27.0	30.0	33.0	36.0
Allowable Unj1 Force 011Fillec Weld.kip/l inear in
[latex]^{†}f =[/latex]	12.73h	14.85h	16.97h	19.09h	21.21h	23.33h	25.45h
Leg Size h, in
Allowable Unit Force for Various Sizes of Fillet Welds kip/linear in
I	12.73	14.85	16.97	19.09	21.2 1	23.33	25.45
7/8	I 1.14	12.99	14.85	16.7	18.57	20.4 1	22.27
3/4	9.55	1 1.14	12.73	14.32	15.92	17.5	19.09
5/8	7.96	9.28	10.61	I 1.93	13.27	14.58	15.91
1/2	6.37	7.42	8.48	9.54	10.61	1 1.67	12.73
7/16	5.57	6.5	7.42	8.35	9.28	10.2 1	1 1.14
3/8	4.77	5.57	6.36	7.16	7.95	8.75	9.54
5/16	3.98	4.64	5.3	5.97	6.63	7.29	1.95
1/4	3.18	3.71	4.24	4.77	5.3	5.83	6.36
3/16	2.39	2.78	3.18	3.58	3.98	4.38	4.77
1/8	1.59	1.86	2.12	2.39	2.65	2.92	3.18
1/16	0.795	0.93	1.06	1.19	1.33	1.46	1.59
*Fillet welds actually tested by the joint AISC-AWS Task Committee. [latex]^{†}f = 0.707h au_{all}[/latex].

Since [latex]22.28 \gt 16.5 \ kip[/latex], weld metal strength is satisfactory.(b) Check shear in attachment adjacent to the welds. From Table A–20,[latex]S_y= 27.5 \ kpsi[/latex].
Then, from Table 9–4, the allowable attachment shear stress is

Table A–20
Deterministic ASTM Minimum Tensile and Yield Strengths for Some Hot-Rolled (HR) and Cold-Drawn (CD) Steels [The strengths listed are estimated ASTM minimum values in the size range 18 to 32 mm ([latex]\frac{3}{4}[/latex]to 11 4in). These strengths are suitable for use with the design factor defined in Sec. 1–10, provided the materials conform to ASTM A6 or A568 requirements or are required in the purchase specifications. Remember that a numbering system is not a specification.] Source: 1986 SAE Handbook, p. 2.15.
1	2	3	4	5	6	7	8
UNS No.	SAE and/or AISI No.	Processing	Tensile MPa (kpsi) Strength,	Yield Strength, MPa (kpsi)	Elongation in 2 in, %	Reduction in Area, %	Brinell Hardness
G10060	1006	HR	300 (43)	170 (24)	30	55	86
G10060	1006	CD	330 (48)	280 (41)	20	45	95
G10100	1010	HR	320 (47)	180 (26)	28	50	95
G10100	1010	CD	370 (53)	300 (44)	20	40	105
G10150	1015	HR	340 (50)	190 (27.5)	28	50	101
G10150	1015	CD	390 (56)	320 (47)	18	40	111
G10180	1018	HR	400 (58)	220 (32)	25	50	116
G10180	1018	CD	440 (64)	370 (54)	15	40	126
G10200	1020	HR	380 (55)	210 (30)	25	50	111
G10200	1020	CD	470 (68)	390 (57)	15	40	131
G10300	1030	HR	470 (68)	260 (37.5)	25	42	137
G10300	1030	CD	520 (76)	440 (64)	15	35	149
G10350	1035	HR	500 (72)	270 (39.5)	20	40	143
G10350	1035	CD	550 (80)	460 (67)	12	35	163
G10400	1040	HR	520 (76)	290 (42)	18	40	149
G10400	1040	CD	590 (85)	490 (71)	12	35	170
G10450	1045	HR	570 (82)	310 (45)	16	40	163
G10450	1045	CD	630 (91)	530 (77)	12	35	179
G10500	1050	HR	620 (90)	340 (49.5)	15	35	179
G10500	1050	CD	690 (100)	580 (84)	10	30	197
G10600	1060	HR	680 (98)	370 (54)	12	30	201
G10800	1080	HR	770 (112)	420 (61.5)	10	25	229
G10950	1095	HR	830 (120)	460 (66)	10	25	248

Table 9–4 Stresses Permitted by the AISC Code for Weld Metal
Type of Loading	Type of Weld	Permissible Stress	n*
tension	butt	[latex]0.60 s_y[/latex]	1.67
Bearing	Butt	[latex]0.90 s_y[/latex]	1.11
Bending	Butt	[latex]0.60 - 0.66 S_y[/latex]	0.52-1.67
Simple compression	Butt	[latex]0.60 S_y[/latex]	1.67
Shear	Butt or filter	[latex]0.30S^†_{ut}[/latex]
*The factor of safety n has been computed by using the distortion-energy theory. [latex]†[/latex]Shear stress on base metal should not exceed [latex]0.40 S_y[/latex] of base metal.

[latex] au_{all}= 0.4 S_y= 0.4 \left(27.5 ight) = 11 \ kpsi[/latex]
The shear stress [latex] au [/latex] on the base metal adjacent to the weld is
[latex] au = \frac{F}{2hl}=\frac{16.5}{2\left(0.375 ight)2}= 11 \ kpsi[/latex]

Since [latex] au_{all} \ge au [/latex], the attachment is satisfactory near the weld beads.
The tensile stress in the shank of the attachment [latex]\sigma [/latex] is
[latex] \sigma = \frac{F}{tl}= \frac{16.5}{\left({1}/{2} ight)2}= 16.5 \ kpsi[/latex]

The allowable tensile stress σall, from Table 9–4, is [latex]0.6 S_y[/latex] and, with welding code safety level preserved,

[latex] \sigma_{all}= 0.6 S_y= 0.6 \left(27.5 ight) = 16.5 \ psi[/latex]

Since [latex] \sigma \le \sigma_{all}[/latex], the shank tensile stress is satisfactory.

Question 3.9.2: A 1/2-in by 2-in rectangular-cross-section 1015 bar carries ...

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