Supporting existing arch structure

[GalileoG]

I need to design a temporary gravity support of a rather large brick arch, approximately 8’ radius, which is to stay in place for several years prior to removal. I am thinking adjustable posts at start/middle/end point of arch, with timber beams that span between each post, and notched for bearing (I am aware of the concern of splitting possibly emerging from the notches, but I haven’t come up with another bearing detail that works yet.) I will then have planking or joists that span between each timber beam, wedged snug to the uneven brick surface of the arch. Any other framing/support ideas? Would appreciate your input.

 

[dhengr]

GalileoG:
Provide a sketch with plan, elevation and wall section with enough detail, dimensions, loadings, etc. so we can understand what you’ve really got going on. What’s holding this arch up now, and what’s going to be removed and remaining? What are the loads remaining, and your support points below the arch? You may have a substantial thrust in the plane of the wall, to pick up, depending upon what you are removing; plus any loads perpendicular to the wall, wind, etc. Many times you can laminate a wooden arch out of short pieces of 2x12's or some such, with the top cut to more or less match the brick arch soffit, then a little shimming. You could actually make some form of a bowstring truss/framed wall, deep box beam, sheathed with 3/4" plywd. or osb. Apply some ext. finish for weather protection.

 

[MiketheEngineer]

Scaffold shoring??

 

[shobroco]

Put sandbags on top of your shoring to actually fit the arch & support every brick, but if you're not sopporting the columns (walls?) that support each end of the arch, good luck.

 

[paddingtongreen]

Are you removing the ends of the arch? the supports? Will there be more load on the arch at the beginning or the end?
The problem is that you need the temporary support to push up, not radially and that will be difficult at the ends of the arch, but radially may crack the arch in the middle. My first thought was to just support the ends, but you may be doing work that prevents that from being satisfactory. Without more information, it is hard to know what to advise.

Michael.
Timing has a lot to do with the outcome of a rain dance.