How Do Multiple Wires Affect Stress Distribution in Steel Brackets?

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DYLAN4321
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Plate with hole help
Hi,

I have developed a catenary software that calculates the tension force resulting from the wire and now I am working on suitable fixing methods and including the option for this within the software.

Has anyone got any guidance on working out the stresses applied on the attached applications? Also how would the circular plate act if there were multiple wires pulling in different directions?

I have done a quick mock up for a plate with multiple holes, but this isn`t really applicable to these applciations given the holes are positioned close to the edge of the plates.

Any help will be appreciated
 
Attachments
  • Engineering drawing of a steel bracket: an isometric view of a wall plate with a vertical gusset and horizontal base plate, and a third-angle orthographic front view with dimensions 200, 6, 15, 75, 30, 60, 110, R20 and Ø20 for two holes.
    Example A.jpg
    20 KB · Views: 212
  • Engineering drawing of a steel pole with a welded top cap and a detail A showing three equi-spaced gussets and two M20 cable glands, plus a plan view of a square base plate with a circular ring and 120 degree gusset spacing.
    Example B.jpg
    26.7 KB · Views: 194
  • Engineering drawing of a steel bracket: a side view with a triangular profile and a circular hole of 18 mm diameter, and a front view of a rectangular plate, 150 by 150 mm, with four 12 mm holes and a central hinge-like knuckle.
    Example C.jpg
    19.6 KB · Views: 240
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Welcome!
It is difficult for me to make sense of the wires you mention and the three attached drawings.
Could you explain the assembly a little more?
Thank you.
 
Hello,

Thank you for your reply.

I have attached an image of an example of the mounting arrangement. Basically a Dee shackle fits through the hole in the plate and then the turnbuckle with the centenary wire is fitted to the shackle.

Thanks
 
Attachments
  • Three separate parts shown with plus signs between them: a stainless steel turnbuckle with a fork end, a D-shaped shackle with a pin, and a square galvanised steel plate with four corner holes and a keyhole-style slot.
    Catenary Mounting Arrangement.jpg
    12.3 KB · Views: 188
  • Line drawing of a span between two poles with a tree in between, showing a wire carrying several hanging fittings spaced along it, labelled Various Lengths, 279 and 230, with the letters MC.
    Example Mounting.jpg
    21.7 KB · Views: 182
Thanks anyway.

I have attached another sketch which shows the direction of the tension force applied.

Say as an arbitrary force of 1kN applied in all directions?
 
Attachments
  • Engineering drawing of a steel bracket with a base plate, vertical gusset and two holes, shown in isometric view and orthographic front view with dimensions 200, 6, 15, 75, 30, 60, 110, R20 and Ø20, plus blue arrows showing force direction.
    Example A Force Direction.jpg
    22.6 KB · Views: 176
  • Engineering drawing of a steel pole with a welded top cap and a gusset detail, with blue arrows showing tension directions from a 286 mm bolt circle plate with 120 degree gusset spacing.
    Example B Force Direction.jpg
    30.6 KB · Views: 167
  • Engineering drawing of a steel bracket: left side view shows a tapered plate with a 18 mm hole and R27 radius, with dimensions 97, 70, 27 and 18; right side shows a 150 by 150 plate with a central 100 mm hinge section, four Ø12 holes to suit M10 fixings at 25 mm offsets, and R5 corners.
    Example C Force Direction.jpg
    20.2 KB · Views: 193
Several cases need to be calculated when designing brackets. For the region around the attachment holes, the following need to be calculated:
1) Bolt shear
2) Compressive failure in bracket
3) Shear failure in bracket
4) Tension failure in bracket

The rest of the bracket is complex. The following quote from my copy of Manual of Steel Construction, 9th Edition illustrates the point:

The actual distribution of stress in the tee flange or angle leg and the extent of prying action are extremely complex. ... Good correlation between estimated connection strength and observed test results has been obtained using theory of Ref. 1. Design and analysis procedures based on this theory have been developed in Refs. 2 and 3.

I recommend that you study the CE Machinery Directive and applicable codes relevant to steel construction in your country. The codes have standard procedures for designing connections that result in safe connections. Those standard procedures have been tested and are proven to work. Trying to do your own analysis is what we call "reinventing the wheel", and can lead to unsafe results.