End PLate Moment Connection (with Large Moment) for SDC D SMF
End PLate Moment Connection (with Large Moment) for SDC D SMF
(OP)
I was designing an end plate moment connection for a SMF Building at SDC D, and having trouble with very large demand moment (3,000 kN-m) due to overstrength. My girder is 800mm deep. I
1. I checked DG and it seems the most i could do was 8 tension bolt connection (2 hor x 4vert each flange, 16 total bolts at joint). Since my column was fairly large and is a built-up section, i was thinking of making more tension bolts, say 16 tension bolts (4 hor x 4 vert each flange, 32 total bolts at joint), but was worried i may have deviated any AISC seismic design rule.
2. I could make a haunch under the girder, but also worried i may deviate the "protect zone rule"
3. My other option into make Bolted Flange Plate (BFP). But at a given overstrength connection force, i may need to provide 4 columns of bolts. Could i do this without deviating any AISC rule (typical detail i see shows only two bolt columns (1 each side of flange)
4. How do we establish the particular location of protect zone for a SMF frame?
Any guidance would be highly appreciated.
1. I checked DG and it seems the most i could do was 8 tension bolt connection (2 hor x 4vert each flange, 16 total bolts at joint). Since my column was fairly large and is a built-up section, i was thinking of making more tension bolts, say 16 tension bolts (4 hor x 4 vert each flange, 32 total bolts at joint), but was worried i may have deviated any AISC seismic design rule.
2. I could make a haunch under the girder, but also worried i may deviate the "protect zone rule"
3. My other option into make Bolted Flange Plate (BFP). But at a given overstrength connection force, i may need to provide 4 columns of bolts. Could i do this without deviating any AISC rule (typical detail i see shows only two bolt columns (1 each side of flange)
4. How do we establish the particular location of protect zone for a SMF frame?
Any guidance would be highly appreciated.





RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
I tried to follow through some example on seismic design guide for SMF and saw column design taken with redundancy factor Axial and Moments, but only verified with Overstrength at Axial force (no moment). In my understanding, joints, say my concerned end plate moment connection, must be designed with all forces taken at seismic overstrength factors to consider connection ductility.
I hope somebody could enlighten me at this point.
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
As i read through Chapter 7, some notes troubled me:
A. Please share some thoughts about the wisdom in the idea of beam limitation at Section 7.3.1 (4) "Beam flange thickness is limited to a maximum of 1 in. (25 mm)". I used Japanese built-up girder BH800x300x16x32 as i need higher stiffness against drift. I could not go to deeper beam as i have SMF frame span to depth ratio limit also. I wish to understand the logic, and if could be possibly waived.
B. As with another item Section 7.3.1 (3, beam weight is limited to maximum of 224kg/m. My section 261 kg/m. How strict is this rule?
C. There was prequalification exception saying "Bolted flange plate connections in SMF systems with concrete structural slabs are only prequalified if the concrete structural slab is kept at least 1 in. (25 mm)
from both sides of both column flanges." The building was SMF Steel frame with 200mm thick slab on metal deck, sitting just above the top flanges with stud provision. I could not comprehend the English construction. Please help me interpret.
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
(C) I dont have time to draw a detail. But, picture a plan view of the column, from each face would be a 1" gap which would have no concrete.
(D) No, drift requirements assume that the building is going beyond elastic. This comes from forming plastic hinges in the beams. The checks given in AISC 358 are to ensure that the column or connection do not fail prior to the develop of Mpr and Vpr. If you are relaying on the extra energy dissipation from a SMF you need to ensure that you can properly develop all the forces.
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF
RE: End PLate Moment Connection (with Large Moment) for SDC D SMF