Use of lighter materials instead of steel and aluminum in railroad cars and track.

[Overmod]

Murphy Siding

I don't know why no one has mentioned titanium. Surely that would be lighter.

Not light on the pocketbook, though!  And pyrophoric as hell in accidents -- fountains of sparks.

Hell, we could mention columbium, zirconium, vanadium, molybdenum and all the other fun things admixed with titanium to make interesting things.  They are expensive too...

[CandOforprogress2]

http://bgr.com/2018/02/08/super-wood-densification-building-material/

Well here comes wood boxcars again

 

[Paul_D_North_Jr]

Further regarding Hybrid Composite Beams ("HCB"): 

There's an article in the current Railway Track & Structures (April 2018) in the "TTCI R&D" department (pgs. 12 - 14), summarized as "Revenue service test results are presented for hybrid composite beam spans".  It has some interesting graphics of mid-span "displacement" (deflection) and "Average bending strain peaks" for both BNSF and CP trains.  This link should take you to that issue, then flip through to those pages: 

https://issuu.com/railwaytrackstructures/docs/rts_0418digital/1?e=5257055/60378867 

There's also a pretty good article on Norfolk Southern's new Portageville, NY arch bridge - 963 ft. long, x 235 ft. high - "Norfolk Southern's ARCH Spans Many Challenges" - on pags. 22 - 24 and 26. 

- PDN. 

 

[BaltACD]

In the quest for lightness - people overlook how mass and gravity work in holding a railroad together.