Regarding your believings that the soil don't have to be compacted near the pipe, you'll be really surprised how this little compaction work (compared to 17m trench excavation) change the pipe response. I'm analyzing a pipe installed with no compaction at all which has failed as if it was made...
I guess you are asking if you need to place something like a shearwall to support the elevator's dead and live load. If this is the case, and it's a mechanical elevator (not an hydraulic one), it's vertical load components are taken at the top of the system, usually you have a slab there which...
