Shear area of Semicircular Lug
Shear area of Semicircular Lug
(OP)
For pin-connected members (square end gusset plate or lug), the following limit states apply:
1. Tension on the net effective area:
Pn = (2)x(t)x(beff)x(Fu) (ASIC 13, eq. D5-1)
2. Shear on the effective area:
Pn = (0.6)x(Asf)x(Fu) (ASIC 13, eq. D5-2)
3. Bearing Strength
Pn = (1.8)x(Fy)x(Apb) (ASIC 13, eq. J7-1)
4. Shear in Pin
Rn = (Fnv)x(Ap)
However, for a round-end plate (or semicircular lug), what is the Asf? (please see the next .jpg I will post to see the shorter failure plane I am referring to).
Is the shear rupture (i.e., different failure plane) the only thing that changes between a square and round pin-connection plate? Thanks.
1. Tension on the net effective area:
Pn = (2)x(t)x(beff)x(Fu) (ASIC 13, eq. D5-1)
2. Shear on the effective area:
Pn = (0.6)x(Asf)x(Fu) (ASIC 13, eq. D5-2)
3. Bearing Strength
Pn = (1.8)x(Fy)x(Apb) (ASIC 13, eq. J7-1)
4. Shear in Pin
Rn = (Fnv)x(Ap)
However, for a round-end plate (or semicircular lug), what is the Asf? (please see the next .jpg I will post to see the shorter failure plane I am referring to).
Is the shear rupture (i.e., different failure plane) the only thing that changes between a square and round pin-connection plate? Thanks.






RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
BA
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
conservatively use 2*(the distance from the edge of the hole to the edge of the lug) on the CL of the hole.
less conservatively, project a radius at 40deg to the CL of the lug. project this point (on the edge of the hole) parallel to the CL of the lug to the edge of the lug. Use 2*this distance.
RE: Shear area of Semicircular Lug
Rn = 1.2 Lc t Fu, where Lc is your distance from the edge of hole to edge of plate. This is the same as your equation 2 above, with Asf = 2*Lc*t, "2" being because there are two shear planes.
In your first sketch, with the square end, it seems very tedious to actually calculate the length of the dashed line you show. I would use the Lc distance and be done with it. The extra length you'll gain isn't worth the effort.
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
for me bearing is based on the pin diameter*thickness; edge distance enters into the bearing atrength (dependent on e/D). ... the the OP says in para (c)
shear tear-out is the lug shearing apart. not sure why you have (a+D/2) ... i'd use "a" which is clearly defined (minimum distance from hole to edge of lug).
RE: Shear area of Semicircular Lug
I checked the equations for tension on pin-connected members in AISC specification D5, and it does show Asf = 2t(a+d/2). This assumes a shear failure at the edges of the hole, out to the edge of the plate. Instead of tearing through a single line of material, you're tearing a strip out that is as wide as the hole. However, I would use "a" and neglect the d/2 contribution to be conservative.
RE: Shear area of Semicircular Lug
"Pinned Connection Strength and Behavior," Journal of Structural Engineering, Vol. 132, No. 2,
American Society of Civil Engineers, Reston, VA, 2006.
"ASME BTH-1 Pinned Connection Design Provisions," Practice Periodical on Structural Design
and Construction, Vol. 13, No. 2, American Society of Civil Engineers, Reston, VA, 2008.
I found them from the attached excel document. The excel document shows the calculation, but I would like to see the document myself. I guess the only next step is to purchase the document and see for myself.
Any other suggestions?
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug
RE: Shear area of Semicircular Lug