Yes, apparently lead is a possibility... though I would expect there may be
future environmental concerns when it comes to demolition time. see the
'high density concrete' entry in the table at:
http://www.roymech.co.uk/Useful_Tables/Matter/Concrete.html
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Pat Barthelow
> Sent: Wednesday, January 17, 2007 23:22
> To: towertalk@contesting.com
> Subject: [TowerTalk] Concrete with Lead added (?)
>
> Folks:
>
> Has anyone heard of adding lead to concrete mixes, to increase
> weight/density? I just was told that the Jamesburg Earth Station, with
> huge
> amount of concrete and rebar required for the self supporting 30 meter
> diameter dish building and foundation, had some sort of lead shot
> entrained
> in the concrete, in order to increase weight, and, ostensibly to reduce
> the
> foundation volume required to support the (free standing) big dish.
> Rumor
> had it, some of the concrete trucks [see below] broke drive train and
> suspension components, due to their loads' extra heavy weight due to the
> lead that was put in the concrete. I am trying to validate the story.
> In
> the photos below, the concrete portion of the antenna support pedestal,
> extends to the point where the attachment bolts can be seen at the
> perimeter
> of the base of the steel turret. The concrete continues to a deep and
> heavily reinforced foundation.
> Is it possible that, like any free standing tower, WEIGHT is the driving
> factor in foundation deisgn, and in order to reduce cubic yards of
> excavation, and concrete, that lead was added to get enough weight into
> this
> foundation?
>
> Jamesburg Earth Station Pictures:
> Picture taken 2006
> http://www.longandflatsociety.com/Galleries/JamesburgEarthStation/tabid/46
> 6/Default.aspx
>
>
>
> Pictures from Late 60s, during construction:
> Concrete Trucks, Foundation Pour
> http://www.comsat-
> history.com/albums/Jamesburg/Jamesburg_Dec_11_1967_Pouring_concrete_for_an
> tenna_footings.sized.jpg
> Footing
> http://www.comsat-
> history.com/albums/Jamesburg/Jamesburg_Jan_12_1968_Footing_of_antenna_bldg
> _forms_for_ant_lower_pedestal_foundation.sized.jpg
> Pedestal
> http://www.comsat-
> history.com/albums/Jamesburg/Jamesburg_Jan_23_68_Antenna_mount_with_founda
> tions_for_antenna_bldg_in_foreground.sized.jpg
> Pedestal
> http://www.comsat-
> history.com/gallery/Jamesburg/Jamesburg_March_12_1968_Antenna_complex?full
> =1
> Antenna Lift
> http://www.comsat-
> history.com/gallery/Jamesburg/Jamesburg_May_27_68_Lifting_antenna_reflecto
> r_into_place
> 73,
> Pat AA6EG aa6eg@hotmail.com
>
>
> _______________________________________________
>
>
>
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