Steam Tunnel Design
Steam Tunnel Design
(OP)
I'm doing a steam tunnel (culvert) for a precast company and wanted to see if anyone had a template or sequence that I could use to guide me through the hand calcs. This is for the cover slab, walls, and base slab. The slab is a 2 way slab.
With box culverts, I have a great software tool but wanted something for this effort. I know PCA has a version, but I wanted to stay in excel if possible. Thanks!
With box culverts, I have a great software tool but wanted something for this effort. I know PCA has a version, but I wanted to stay in excel if possible. Thanks!






RE: Steam Tunnel Design
To accurately do this by hand you would need to do something like moment distribution. To be down and dirty (and conservative), you could assume that your maximum moment is (WxL^2)/8 and provide that steel top and bottom of each slab, and also make it continuous around the corners.
The best way is to model your tunnel using analysis software. We use RAM Advanse.
Also, make sure you consider the shear strength of the concrete. You want it thick enough so that you don't need and shear reinforcing in your slabs. You also need your slabs thick enough so that 2 layers of rebar are constructable and you meet all of your ACI clear cover requirements.
RE: Steam Tunnel Design
You may still want to consider a heavy truck or fire truck driving over it.
RE: Steam Tunnel Design
RE: Steam Tunnel Design
I went with wl^2/8 for this effort. The precast company was good with it.
Yeah, it's under a parking lot with H-20 loading criteria.
Thanks again!
RE: Steam Tunnel Design