Tower Time – Part 4 – Foundation

Pour complete
Pour complete

With winter just around the corner, working hard to get the foundation completed soon, as it will need to cure for 3 weeks before standing the tower up on it.

Prepping the site

Decided to re-purpose a turn-around on the second driveway and place the tower in this location. This site offered the fewest sight lines from our house and the neighbors. First job was to remove the gravel base and pull out the culvert pipe for reuse elsewhere.

The last of of the gravel scraped from former turn-around
The last of of the gravel scraped from former turn-around
Cleaning off the culvert pipe
Cleaning off the culvert pipe
Final clean up
Final clean up
Former turnaround with a rough outline of the tower base staked out.
Former turnaround with a rough outline of the tower base staked out.

Tower base prep

Rohn offers two bases for the RSL line, a short base which is not adjustable and a threaded rod system which is adjustable. I was advised not to use the non-adjustable as the name implies once set no adjustment for vertical can be made.

Simple to assemble, templates and everything you need other that basic hand tools are in the kit.

IMG_3096

 

Excavation

The plans call for a 10’x10’x4’4″ foundation filled with 16 yards of 4500psi mix. For reinforcing the design calls for two mats of number #7 rebar (7/8 inch diameter) spaced evenly in a grid pattern. One on the bottom and one on the top of the foundation. Each mat weighed in at right around 400lbs.

Bottom rebar mat, layout and tied outside of the form.
Bottom rebar mat, layout and tied outside of the form.
Top mat, also laid out and tied outside the form.
Top mat, also laid out and tied outside the form.
Breaking ground !!!
Breaking ground !!!

 

Checking depth
Checking depth
One side pretty much done.
One side pretty much done.
Getting close to final dimensions
Getting close to final dimensions
Bottom mat in place
Bottom mat in place

As it was Thursday and rain was coming on Monday, had to get it finished Thursday night for inspection in the morning. And a pour scheduled for just after noon.

It was a late night.

Ready for inspection
Ready for inspection
Picking up for the night
Picking up for the night
Top mat support detail, 7/8 rebar was driven into the ground and bent at a right angle and tied into an X.
Top mat support detail, 7/8 rebar was driven into the ground and bent at a right angle and tied into an X.

Pouring

Waiting for the concrete to arrive
Waiting for the concrete to arrive, trenches for ground system and feedlines can also be seen.

For strength a #4 slump was ordered, this is a dry mix close to mashed potatoes in consistency. It stays where it is poured and if allowed to pile up, it will push things around in the form . To prevent this the crew slowly dropped around the form and used a vibrator to spot reduce the viscosity. Which allowed the mix to flow around versus push around anchor rods and such.

Start of the first truck.
Start of the first truck.
Second truck arriving
Second truck arriving
Getting near the top.
Getting near the top.
Striking off the pour.
Striking off the pour.
Pour complete, feedline trench to the house is viewable in the background.
Pour complete, feedline trench to the house is viewable in the background.

Special Thanks

This project would not have been possible without the pro’s from Huber Construction. Special thanks to Mike Huber and his team for getting the job done on time and on budget.

Next

On deck next is completing the ground systems and feedline routing before the ground conditions deteriorate or the weather gets too cold to glue PVC.

Oh yeah and I still have this big erector set to assemble 😉

Until next time 73’s, Jay

 

Be the first to comment

Leave a Reply

Your email address will not be published.


*


This site uses Akismet to reduce spam. Learn how your comment data is processed.