Improvements in Concrete to be used in the Construction of Vaults, Roofs, Arches, Floors, and the like.
Year: 1890

page_text: Date of Application, 23rd May, 1890
Complete Specification Left, 21st Feb., 1891-Accepted, 23rd May, 1891
PROVISIONAL SPECIFICATION.
Improvements in Concrete to be used in the Construction of Vaults,
Roofs, Arches, Floors, and the like.
I, FREDERICK SANG, Architect and Surveyor, care of Messrs. Mackrell, Mason
and Godlee, of 21 Cannon Street, in the City of London, do hereby declare the
nature of this invention to be as follows:-
According to my invention I form a concrete of tufa sand and Portland or like
cement.
The tufa sand is a volcanic tufa found in horizontal layers or strata of from one
to several feet in thickness in entensive beds on both sides of the upper and middle
Rhenish Provinces of Germany particularly between Bonn and Coblentz and is
composed of small pellets or grains of tufa in an open porous condition and not
closely compacted together as in tufa stone. The pellets or grains in their natural
state and without -any preliminary grinding or crushing-1-admix with a compara-
tively small quantity of Portland or other cement. When it is to be used the
required quantity of water is mixed with it as when making ordinary mortar and
the mixture is moulded to the shapes required and when set it forms a concrete
which combines lightness with strength and is also an excellent non-conductor of
heat so that it may advantageously be used for covering roofs or the like or for
forming the domes of bakers ovens or for other such like uses.
Dated this 1st day of Mar 1900
COMPLETE SPECIFICATION.
Improvements in Concrete to be used in the Construction of Vaults,
Roofs, Arches, Floors, and the like.
I, FREDERICK SANG, Architect and Surveyor, care of Messrs. Mackrell, Mason
and Godlee, of 21 Cannon Street, in the City of London, do hereby declare the
nature of this invention and in what manner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
According to my invention I form a concrete of tufa sand and Portland or like
cement.
The tufa sand is a volcanic tufa found in horizontal layers or strata of from one
to several feet in thickness in extensive beds on both sides of the upper and middle
Rhenish Provinces of Germany particularly between Bonn and Coblentz and is
composed of small pellets or grains of tufa in an open porous condition and not
closely compacted together as in tufa stone. The pellets or grains in their natural
state and without any preliminary grinding or crushing I admix with Portland or
other cement.
The mixing may be effected by hand or by pug mill or edge runners or other
grinding and mixing machinery to reduce the materials to any desired degree of
fineness. The mixing may be effected whilst the materials are in a dry state and
water be added whenever the mixture is required for use as when making ordinary
mortar and the concrete so formed may be then spread or moulded to form
wherever it is to be used or the mixing and addition of water may be carried on
simultaneously and the concrete be at once moulded into blocks of various shapes
either in the form of casements tubes ribbed blocks for forming arches, floors or
the like or in other forms suitable for being used for building purposes like masonry
or ordinary bricks or tiles or other building blocks. A concrete formed in the

page_text: above way
combines lightness with great strength-for example a concrete formed
from a mixture of one half tufa sand and one half Portland cement ground together
is as strong as the best granite and less one half of its weight.
For many purposes however a much smaller proportion of Portland cement may
advantageously be used, say for example a mixture of three to five parts tufa sand
with one part Portland cement.
A concrete formed in the above way is also an excellent non-conductor of heat
so that it may advantageously be used for covering or forming roofs or the like or
for forming the domes of bakers ovens or for other such like uses.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
A concrete composed of tufa sand and Portland or like cement substantially as
herein described.
FREDK, SANG.