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insufficient bar joist bearing
i am investigating an existing building (approximately 1 year old)which has a roof system of bar joists/girders. one particular joist bears only 1-1/2" on the girder. the bar joist specifications require a 2-1/2" bearing. there is another joist on the opposite side of the girder at this location with sufficient bearing. is there a way to reinforce the "end" of this joist or should i add a "seat" to the girder to obtain the required bearing?
if the building is that new, you should be able to get a recommendation from the joist manufacturer. i've seen it done both ways, but 1-1/2" is pretty short. if access is limited, adding a seat extension may be the only way you can go.
that's usually caught by the inspector, if there is one.
only way i've done it is with seat extensions.
i think the joist supplier/designer should be able to come up with joist seat extension design to increase the bearing to the minimum of 2.5 inches.
i have seen this done on past projects and it works fine.
i am curious why are you investigating a one year old structure?
regards,
lutfi

2009-09-09, 07:44 PM	#1
huangyhg 超级版主注册日期: 04-03 帖子: 18592 精华: 36 现金: 249466 标准币资产: 1080358888 标准币	insufficient bar joist bearing insufficient bar joist bearing i am investigating an existing building (approximately 1 year old)which has a roof system of bar joists/girders. one particular joist bears only 1-1/2" on the girder. the bar joist specifications require a 2-1/2" bearing. there is another joist on the opposite side of the girder at this location with sufficient bearing. is there a way to reinforce the "end" of this joist or should i add a "seat" to the girder to obtain the required bearing? if the building is that new, you should be able to get a recommendation from the joist manufacturer. i've seen it done both ways, but 1-1/2" is pretty short. if access is limited, adding a seat extension may be the only way you can go. that's usually caught by the inspector, if there is one. only way i've done it is with seat extensions. i think the joist supplier/designer should be able to come up with joist seat extension design to increase the bearing to the minimum of 2.5 inches. i have seen this done on past projects and it works fine. i am curious why are you investigating a one year old structure? regards, lutfi __________________ 借用达朗贝尔的名言：前进吧，你会得到信心! [url="http://www.dimcax.com"]几何尺寸与公差标准[/url]