Need a book? Engineering books recommendations...
[SEAOC] Bracing Eccentricity[Subject Prev][Subject Next][Thread Prev][Thread Next]
- To: SEAOC(--nospam--at)seaoc.org
- Subject: [SEAOC] Bracing Eccentricity
- From: "Hunt, Tom" <tom.hunt(--nospam--at)fluordaniel.com>
- Date: Tue, 03 Sep 1996 11:20:00 -0700
There seems to be arguments on both sides and in-between on whether the eccentricity in a bolted brace connection should be considered and if so where. Blodgett indicates that if the connection is "rigid" then the moment from the eccentricity should be used in the design of the member, if the connection is "flexible" then the moment should be used to design the connection (bolts and gusset plate) and ignored in the member. "The Seismic Design Handbook", Van Nostrand Reinhold, seems to imply the same thing (assuming most brace connections are flexible) by saying, "In actuality, some eccentricity may occur due to the physical limitations of the connections, but this is usually ignored in the design of the members. However, any eccentricities in the connection must be considered in the design of the connecting bolts or weldments." AISC Manual of Steel Construction, Volume II Connections, completely ignores the eccentricity in both the connection and the member, even in the heavy truss section where the loads are significant and their example uses 2 rows of bolts in one leg. Rick's original question was what to do with a bracing member utilizing a Tee section turned so its flange is bolted flat to the gusset plate. Probably the significance of this design is that the eccentricity is out of the plane of the gusset plane which could cause bending in the weak axis of the plate. I suppose that if you adhere to the AISC design examples then you could ignore the eccentricity for the design in both the member and connection whether the eccentricity is in or out of the plane of the gusset plate OR that this eccentricity should be considered in the design of ALL connections. Does anyone else have any data, tests, reports, etc. to support either of these positions? Thomas Hunt ...
- Prev by Subject: [SEAOC] Bluebook
- Next by Subject: [SEAOC] bridge construction
- Previous by thread: [SEAOC] Type M vs Type S mortar
- Next by thread: [SEAOC] RE: [SEAOC] Type M vs Type S mortar