Friday, December 22, 2017

Bridges Across The Keys - Bob Kranich

Excerpts from A Walk Across Florida by Bob Kranich

As I was sitting there contemplating hiking across this mile- long bridge, a car pulled up.
    “You need a ride?” he offered.
    “You know, that seems like a good Idea,” I said. He had just solved my problem.
    “Not too far,” I said, “I just need to get to the next land.”
I put my pack in the back seat and got in. It seems that this young fella had seen me a couple of times on his way to Miami. From a car point of view, I could see as we sped along just how beautiful the clear emerald blue-green water was. Between the looking, and talking I suddenly realized that we were covering too much distance. I would be in Key West before I realized it!
    “You had better let me out at the next causeway or land!” I suddenly exclaimed.
It had been so very long since I was in a vehicle, that when you think about it, 50 to 60 miles an hour is a mile a minute! In just a few minutes, we had gone 6 miles.
I thanked him for the ride and off he went, in a flash.
I just sat there looking back at the two-mile Long Key viaduct and said out loud, “Not going back.”
I was looking back at the highway bridge built on top of the old railroad bridge and suddenly realized that this was the famous arch bridge. It was one of Flagler’s favorites. Photographs and posters of a passenger train speeding across it were used on stationary, the sides of freight cars, and innumerable brochures. It became a trademark  for the FEC.
The bridge over channel No. 5 was also an arch bridge. I had not seen the side, as I had been contemplating how to cross it. These two bridges, channel No. 5, almost one mile, the Long Key viaduct, 2.3 miles, plus the land in between, meant that I had lost 6 hiking miles through Long Key.
All-in-all, the Florida East Coast Railway bridges numbered 42 for a total of 18 miles. The Long Key bridge was made with 180 spandrel arches, each one spanning 50 feet, and was more than 20 feet above mean high tide.
(Author’s note: Of the 42 bridges, four were too long and dangerous to cross on foot. They were these two bridges which were one and two and one half miles long, the Bahia Honda and the seven mile bridge. So all in all I crossed on foot, 38 total.)
These arch bridges are called Spandrel Arch bridges
This Spandrel Arch bridge construction is very intriguing, The steps are listed below:
1. The ocean floor is cleaned down to the coral lime-stone bottom.
2. Wood posts are driven into the coral, and then a cofferdam is lowered down to the bottom.
3. Two feet of concrete is poured in for a seal.
4. The water is pumped out of the cofferdam.
5. Prefabbed final forms are put into the cofferdam and the concrete poured and built up above the water.
6. All throughout tons of reinforcing steel and connecting rods and rebar are used to tie together each                  new concrete pour.
7. A prefabbed “ring arch” is barged in and set up on two piers using the tide as a lifting device.
8. Side forms and inside forms are made.
9. The concrete is poured into the arch.
10. The final arch is hollow and is filled with gravel.
11. The railroad ties and rails are laid upon the gravel.

About the Author: After getting out of the Army Bob Kranich backpacked from the Georgia border to Key West in a 40 day adventure walk across Florida. His recently published book A Walk Across Florida is available from his website or

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