When my wife and I flew over the river just north of Mobile back in the
60s, we thought they were all anchored there. I have no idea how they
came to be in that one spot.
Jim Nichols
Tullahoma, TN USA
On 2/18/2016 3:27 PM, Bill Pearce wrote:
Well, we did have to keep up production on the liberty ships so our
list could have members from the UK in the 21st century.
-----Original Message----- From: Jim Nichols
Sent: Thursday, February 18, 2016 3:17 PM
To: Olympus Camera Discussion
Subject: Re: [OM] IMG: Repair of WWII Concrete
Bill, I didn't want to get in the way, and didn't have a tape with me,
but I would estimate the concrete at 10 to 12 inches. In the one spot
where I shot the corner, they had already rolled down a thin layer of
clay gravel as a base for the new concrete.
Jim Nichols
Tullahoma, TN USA
On 2/18/2016 3:11 PM, Bill Pearce wrote:
Interesting, and thinner than I expected. In WWII, it was common to
build runways and taxiways out of unreinforced concrete. The
engineers had conversion charts that said if so think with so much
rebar, then so think with none. When I was working for the airplane
factory we did certain kinds of testing at a nearby former Naval Air
Station (Yup in the middle of Kansas) the Hutchinson Naval Air
Station, which was a base for the navy version of the B24, the one
with the single tail. The son of a local rich oilman bought it for
residence and fun, he lived in the tower structure, the actual
glassed in part of the top had sofas around the outside (yes, this
was in the seventies when parties, sex and drugs happened) and
several of the attached buildings had his collections of various
Italian supercars in them. He rented out the place for us to test,
and for gliders and skydiving. Once while testing, we were constantly
irritated by the noise of concrete being broken up. He had contracted
with a local concrete plant to sell them runways for aggregate. Yes,
noiser than jet engines. But the runways were about one foot thick
concrete.
-----Original Message----- From: Jim Nichols
Sent: Thursday, February 18, 2016 2:19 PM
To: LUG@xxxxxxxxxxxxxxx ; Olympus Camera Discussion
Subject: [OM] IMG: Repair of WWII Concrete
I took a walk in the sunshine today at the local airport. Felt good!
This airport was built during WWII as an US Army Air Force training base
for B-24s, hence the concrete was very thick to withstand the wheel
loads. While much of it has held up well, places that received a lot of
traffic have developed cracks. A contractor has been hired to cut out
these broken areas and replace them with new concrete. ( It is
interesting to me that, while concrete made today in our area uses
crushed limestone as the aggregate, I have seen areas of the original
pours that used creek gravel, including a few mussel shells, as the
aggregate.)
This image gives an idea of the thickness of the original concrete.
http://www.gallery.leica-users.org/v/OldNick/Thick+Concrete+3162.tif.html
To tie the new to the old, the old concrete is drilled and rebar is
installed.
http://www.gallery.leica-users.org/v/OldNick/Drilling+for+Rebar+3163.tif.html
About half of this section has been replaced, as the crews work with
manageable pour sections.
http://www.gallery.leica-users.org/v/OldNick/Working+Concrete+3157.tif.html
The rotating mixer drum must be washed out after each pour.
http://www.gallery.leica-users.org/v/OldNick/Wash+Job+3161.tif.html
And then, the truck heads back to the plant for another load. Multiple
trucks were in use, to keep the job moving at a workable pace.
http://www.gallery.leica-users.org/v/OldNick/Going+to+Reload+3165.tif.html
Fuji X-E1 with Fujinon 35/2.0
Comments and critiques welcomed.
--
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