When RAM Connection computes the effective weld length of an HSS T-connection, it correctly applies this rule per AISC 360-16:
When β > 0.85 or θ > 50°, Be / 2 shall not exceed Bb / 4.
However, when computing the effective section modulus of the same connection for in-plane and out-of-plane moments it does not limit Be/2 to Bb/4.
The way I read the code this is not correct. Am I missing some obscure note in the code that allows this or is this an error?
Here’s a sample calc from RC showing what I’m talking about. I did not include the out-of-plane bending calc but it used the same effective width as the in-plane.
Weld calculation for brace member with axial load
Weld strength [Kip] 222.74 118.00 DL 0.53 Eq. K5-5
b = Bb/B
= 8[in]/8[in]
= 1
Be = Min((10*t/B)*(Fy*t)/(Fyb*tb)*Bb, Bb)
= Min((10*0.625[in]/8[in])*(50000[lb/in2]*0.625[in])/(50000[lb/in2]*0.5[in])*8[in], 8[in])
= 7.81[in] Eq. K1-1
(b>0.85) or (q>50) ® (1>0.85) or (90>50) ® True
Bew = Min(Bb/2, Be)
= Min(8[in]/2, 7.81[in])
= 4[in] Eq. K5-5
le = 2*Hb/SinDeg(q) + 2*Be
= 2*8[in]/SinDeg(90) + 2*4[in]
= 24[in] Eq. K5-5
Weld calculation for brace member with in-plane bending
Weld strength [Kip*ft] 64.84 15.00 DL 0.23 Eq. K5-6, K5-2
Be = Min((10*t/B)*(Fy*t)/(Fyb*tb)*Bb, Bb)
= Min((10*0.625[in]/8[in])*(50000[lb/in2]*0.625[in])/(50000[lb/in2]*0.5[in])*8[in], 8[in])
= 7.81[in] Eq. K1-1
ApplyCondition = (Pro/3)*(Fyb/SinDeg((1/W)))2 + Pro*Be*(Fyb/SinDeg((1/W)))
= (0.442[in]/3)*(8[in]/sin(90))2 + 0.442[in]*7.81[in]*(8[in]/sin(90))
= 37.05[in3]