Traps in (underground) concrete passage design?

[drile007]

For the first time I'm going to design (underground) reinforced concrete passage which cross-section is approximately 3x3m. The main purpose is transition passengers from one train platform to the other. The main load is slow train under passage. I'm wondering on which things I should pay special attention? On the first view I just thing on right earth pressures on walls and right train loads. I will pass dynamic analysis since the passage is very small (3m wide)? Are there any other (non-structural) traps?

Thank you in advance

 

[JAE]

Waterproofing.

Expansion joint at one end of the tunnel perhaps?

Backfill control around and over the tunnel to minimize settlements that might damage or distress the tracks above.

 

[drile007]

Thank you JAE...but how should I control backfill...with appropriate compacting?

 

[JAE]

Yes, backfill should be placed in lifts (perhaps 8 to 12 inches thick - (200 to 300 mm) and be compacted to a percent of the Proctor compaction.

 

[csd72]

Groundwater pressures
Expanding overconsolidated clay
point loads from the train wheels
earthquake loads
Reinforcement detailing at the corners
Settlement of surrounding structures

 

[drile007]

What about transition slabs? Are they used in train supporting structures...like on vehicle-bridge structures? Why not?

 

[paddingtongreen]

You really need to go to:

http://www.arema.org/

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