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bar joist identification
i am trying to determine the capacity of existing roof joists for new hvac units.
i found the identification tags, which read "06-8656 nj 12" "20-b7".
here are measurements that i took:
the joist depth is 20 inches.
bearing depth is 2 1/2 inches.
top & bottom chords are cold-formed steel and parallel.
web membs are 3/4" in diameter.
there are two rows of horizontal bridging.
the building was built after 1963.
i could not come up with any spec or load carrying capacities by looking up the sji's "75 year steel joist manual".
thank you for any help to determine joist spec or capacity.
find a job or post a job opening

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[url="http://www.dimcax.com"]几何尺寸与公差标准[/url]

2009-09-07, 02:18 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	bar joist identification bar joist identification i am trying to determine the capacity of existing roof joists for new hvac units. i found the identification tags, which read "06-8656 nj 12" "20-b7". here are measurements that i took: the joist depth is 20 inches. bearing depth is 2 1/2 inches. top & bottom chords are cold-formed steel and parallel. web membs are 3/4" in diameter. there are two rows of horizontal bridging. the building was built after 1963. i could not come up with any spec or load carrying capacities by looking up the sji's "75 year steel joist manual". thank you for any help to determine joist spec or capacity. find a job or post a job opening __________________ 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]