Railroad Rail Piling for Embankment Failures
Railroad Rail Piling for Embankment Failures
(OP)
Railroad rails have been used for years on highway embankment failures as a method of repair, with the rails functioning similarly to cantilever beams/piles. Rails have standard 39ft lengths and come in different weights: 130-133 lb/yd and 136-140 lb/yd.
Assuming proper embedment into rock or firm and stable soil, and all other parameters being the same, would there be a significant loss of factor of safety or other strength penalties with substituting 130-133 lb/yd rails for the heavier 136-140 lb/yd rails?
Assuming proper embedment into rock or firm and stable soil, and all other parameters being the same, would there be a significant loss of factor of safety or other strength penalties with substituting 130-133 lb/yd rails for the heavier 136-140 lb/yd rails?
Rockjoint
rockjoint@yahoo.com





RE: Railroad Rail Piling for Embankment Failures
RE: Railroad Rail Piling for Embankment Failures
The answer depends on what type of wall(?) you are building. If you are using the rails as soldier beams in a wall, the heavier rail may be slightly stronger than the lighter rail. You can calculate the section modulus for each rail section. However, both rails should be relatively weak as soldier beams in bending when compared with H Piles or Wide Flange Beams.
If you are using the rails as driven soil reinforcements, like pin piles as assumed by BigH, then I would think that both rails are relatively strong. However, the heavier rail should be a little stronger since it has a greater cross-sectional area to resist shear.
No clear answer can be given unless we know what you are trying to do with the rails.
RE: Railroad Rail Piling for Embankment Failures
RE: Railroad Rail Piling for Embankment Failures
Although I only read the paper, I was always concerned that the used rails may have become brittle as a result of work hardening and that the minor horizontal displacement of the slope resulted in catastrophic results.
Maybe someone can shed some light on this issue. Presumably the railways remove rails for some good reason. Is it simply wear or is there a change in the material property that might affect their use in the situations suggested here.
RE: Railroad Rail Piling for Embankment Failures
In an effort to prevent closing of both lanes of traffic, especially in limited space areas, and where remediation with rock buttress material may impact streams, etc., this concept has been utilized on small failures.
The used railroad rails are placed into drilled holes, which are then backfilled with crushed stone or concrete. A portion of the rail is exposed above natural ground surface where lagging (often guardrail) can be placed against the rails. Crushed stone then may be placed against the lagging to bring the backfill up to shoulder grade. Note that the rails are 39 feet in length, limiting where this concept may be used.
We consider this remediation concept for shallow failures, especially where bedrock is located along the failure surface. In all cases over the last several years, the failures have been successfully stabilized.
I am a geologist, not an engineer. I work with the engineers, however, to recommend where such remedial measures may be considered. Of course, other methods such as tie-back walls and rock fill may be used.
Rockjoint
rockjoint@yahoo.com
RE: Railroad Rail Piling for Embankment Failures
Good Luck!
RE: Railroad Rail Piling for Embankment Failures
Rockjoint
rockjoint@yahoo.com