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grade beam elevation difference
i have continuous grade beam 8"x24"( with 2-1" bars t&b)running on top of pile. at one pile location i have grade beams meeting at different elevation. the difference is 6" between the bottoms of two beams.
my question is how can i make continuity of steel bars because of 6" elevation difference? my design for grade beam was based on continuous beam on top of pile and now that continuity is broken.
will the dowels in the "z-shape " from one beam to other will do anything?
check out our whitepaper library.
don't use z shaped bars! the stress will cause the bar to straighten and break out concrete.
deepen the bottom of the upper beam 6" for the length of at least a #8 tension lap splice plus 3".
extend the top and bottom bars from the lower beam into the other beam for a length of a tension lap splice. bars need to meet the requirement of a non-contact lap splice.
i hope this helps!
jike has given you good advice, but his comment about z shaped bars needs clarification. z bars when used should always go from top to bottom of the members at the step, never from bottom to bottom or top to top. draw yourself a little picture and you will see what he means about the tensile stress in the bar trying to straighten the bar, thus breaking out the internal corner of the concrete.

2009-09-09, 02:57 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	grade beam elevation difference grade beam elevation difference i have continuous grade beam 8"x24"( with 2-1" bars t&b)running on top of pile. at one pile location i have grade beams meeting at different elevation. the difference is 6" between the bottoms of two beams. my question is how can i make continuity of steel bars because of 6" elevation difference? my design for grade beam was based on continuous beam on top of pile and now that continuity is broken. will the dowels in the "z-shape " from one beam to other will do anything? check out our whitepaper library. don't use z shaped bars! the stress will cause the bar to straighten and break out concrete. deepen the bottom of the upper beam 6" for the length of at least a #8 tension lap splice plus 3". extend the top and bottom bars from the lower beam into the other beam for a length of a tension lap splice. bars need to meet the requirement of a non-contact lap splice. i hope this helps! jike has given you good advice, but his comment about z shaped bars needs clarification. z bars when used should always go from top to bottom of the members at the step, never from bottom to bottom or top to top. draw yourself a little picture and you will see what he means about the tensile stress in the bar trying to straighten the bar, thus breaking out the internal corner of the concrete. __________________ 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]