The crushed stones you see alongside railroad tracks are what is known as ballast. Their purpose is to hold the wooden cross ties in pl...

Why Crush Stone ( Ballasts ) are Used in Railway Track?


The crushed stones you see alongside railroad tracks are what is known as ballast. Their purpose is to hold the wooden cross ties in place, which in turn hold the rails in place. 
Think about the engineering challenge faced by running miles of narrow ribbons of steel track on top of the ground: they are subject to heat expansion and contraction, ground movement and vibration, precipitation buildup from rough weather, and weed and plant growth from underneath. Now keep in mind that while 99% of the time they are just sitting there unburdened, the remaining 1% they are subject to moving loads as heavy as 1,000,000 pounds (the weight of a Union Pacific Big Boy locomotive and its tender). 

Put all this together, and you have yourself a really, really interesting problem that was first solved nearly 200 years ago, and hasn't been improved since!
Watch video and learn more

0 Comment: