Bridges
Something that people have done for decades is to use used railroad flat cars for bridges for residential uses.   I've done a few of them over the years.  Each site will need to have the footings adjusted for the local conditions, sometimes people want different driving surfaces and they will all need some sort of handrail.

Bridges:

Railroad Flat Car Bridge This is a typical bridge made from a flat car.  To see the Floor Plan and Elevations Click Here Set plans generally consist of 1, sometimes 2, drawings.  Engineering plans for these type of bridges is usually in the $2,000 to $3,000 range plus and printing & shipping costs.	85' x 10'
Covered Railroad Flat Car Bridge This is a typical bridge made from a flat car but this one is covered.  To see the Floor Plan and Elevations Click Here Set plans generally consist of 4-5 drawings..  Engineering plans for these type of bridges is usually in the $4,000 to $5,000 range plus and printing & shipping costs.	85' x 10'
Railroad Cars Commercial Complex This is not a bridge but show how you can use railroad cars for other uses.  This was some preliminary plans I did for some retail spaces.  To see the Floor Plan and Elevations Click Here To see a similar installation, Click Here