huangyhg

removing load bearing wall - shoring issues
i am designing an addition which requires removing about 100 feet of load bearing wall (also serves as shear wall for a single story bldg). i'm replacing it with posts and beams and making frames rigid to handle the lateral loads. this wall supports bar joists spanning about 25 feet. my past procedure is to state on the plans "provide shoring as required". should the plans include shoring design? i think this is part of the contractor's means and methods, and i don't want to design it. but should i ask for the shoring design to be submitted for approval, and sealed by a pe, etc. what's your standard practice?
shoring calcs/drawings signed and sealed provided to eor. but i don't think you're going to be going through a detailed check of it, either.
i wouldn't do it unless it's in your scope of work. if you're just doing the addition, i don't think that would include shoring. technically, this is means and method and thus the contractor's responsibility to get a specialty engineer to design it and provide drawings for it.
what you can do is at least indicate a required shoring load and locate where on the joist (i.e. panel point) the shoring should occur.
the loading on the roof or floor used to determine this shoring load should be based upon asce 37.
i'd agree that a shoring plan should be a required submittal.

shoring the bar joists may be tricky. they aren't designed to be supported except at their ends. a supporting compression load could damage the joists' diagonals. are you leaving any of the existing wall in place which could support the joists while you remove only a lower portion of the wall? if so, possibly the wall under the joist ends could be supported rather than the joists. i think you should give as much information as possible to the contractor so that he can intelligently design the shoring. give him loads and information on the joists. you need to make sure your addition design is buildable.
mikee55,
did 5 years of this; the "shoring as required" note will work. you'll also need to note the imposed loads: dead, live and lateral. the general contractor will take your plans to a shoring contractor, that may have in-house engineers, the national companies like patent, efco, aluma usually do, or at least a regional engineering office. they will be the ones that will design the shoring. the tricky part may be the lateral loads and their load paths. that might require a conference call. as for the bar joist, "cribbing" is usually added at the closest panel point to the end. this consist of either steel or wood mini-columns that connect the top and bottom chord at that first panel point. the shoring engineer will also design this. just re
peinc is right - if you do shore up bar joists, the shoring needs to go at the panel point, unless you add vertical angles to send the shoring point support reaction up to the upper panel point.
also, x-bridging between joists is required along the shoring length.

even if you shore at the panel points, you need to watch that you don't buckle a diagonal tension
true
my experience was on the "other side" in the field working with seal drawings and inspecting shoring: the issue with the diagonal tenion
yes, he has to ensure the project can be done asfely, since he is the eor for this particular task.
this is kind of interesting because i don't think i have ever seen shoring being required as a submittal to the eor.
"but should i ask for the shoring design to be submitted for approval, and sealed by a pe, etc. "
if we see a drawing from another engineer as a submittal we have taken on a much larger responsibility i feel. if i see a shoring submittal, now i have to make sure they know what they are doing and that is not normally in our scope. this could impact the existing structure if the shoring is not designed correclty so i would also feel obligated to get involved in checking that too, specifically for the shoring design.
we normally have left the "shoring as required to be designed by contractor's hired engineer...." note and not required a submittal. i would give loads for their shoring design though.
i am interested to hear more on shoring submittal reviews and eor responsibility. it seems that reviewing shoring submittals is getting into means and methods and could become very involved, and not something usually in our contract.

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