Note: Descriptions are shown in the official language in which they were submitted.
Background of the Invention
In building dwelling houses, pre-fabrica-ted ~ooting
blocks now have come into use. However, pre-fabricated
footing blocks canno-t be used for larger buildings which
are constructe~ on a pile foundation. Because it is im-
possible to make exac-tly equal the levels of -the -tops of
all -the piles after they have been driven into the soil, ~,
and therefore a level footing cannot be obtained by placing ~'
pre-fabricated ~ooting blocks thereupon. Thus, in the
construction of such larger buildings, the con-tinuous foo-t-
ings are formed in the conventional manner on the building
site. The object of this invention is to provide a new
method for forming a continuous footing for a large building
to be buil-t on a concrete pile founda-tion and a new leveling
element w'hic'h is used for said new me-thod.
Summar~ of the Invention
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~ T'his invention provides a leveling element for pre-
,~ fabricated footing blocks, said leveling element comprises
a base plate having an aperture for receiving -the -top of a
pile and side walls having indentations or recesses for
receiving a pre-fabricated footing block or blocks.
Fur-t'her, t'his invention provides a method for forming
a continuous ~oo-ting for cons-tructing a building on a
concrete pile foundation comprising: placing a leveling
element comprising a base plate having an aperture for
receiving t'he top of a concrete pile and side walls having ,~
indentations at each pile so -that said aper-ture receives
-the top of each of concrete piles remaining above t'he ground
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level after they 'have been driven into the soil, breaking
the top of -the concrete piles so as -to expose the reinforcing ;,~
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bars of`-the piles, bending down -the exposed reinforcing bars
onto -the surface of the base pla-te, placing pre-fabricated
~ooting blocks so -tha-t at leas-t a par-t of each black is
received in one of -the indenta-tions.
Usually, before the leveling elements are placed, a
ballast (rubble and gravel and sand if necessary) bed is
formed in accordance with t'he la~out of the building to be
built, and it is leveled all over -the layout before the
leveling elements are placed.
The leveling element can be made of metal, but it is
usually made of ferroconcrete. The standard shape of t'he
leveling element is square or rectangular in the plan view
and like a body of a box. But it can be cross or T-shape or
even round in the plan view.
Now the invention is described in de-tail with reference
to t'he a-t-tached drawings.
Brief -escription of t'he Drawin~s
, Fig. 1 is a perspective view of a leveling element of
`l the standard type in accordance wit'h this invention.
Fig. 2 is a sc'hematic cross-sectional view of the level-
ing elemen-t of Fig. 1 s'howing~it in -the position to receive
the top of a concre-te pile.
~ Fig. 3 is a schematic cross~sectional view of the foo-t-
,l ing prepared according to the met'hod of this invention.
Fig. 4 is a schematic perspective view of a part of a
' continuous footing formed by t'he method of t'his invention.
"' Figs. 5, 6 and 7 are perspective views of other embodi-
' ments of the leveling element of -this invention.
Detailed Description of_the Invention
3 The leveling element of this invention typically has ;-
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a shape as shown in Fig. 1. ~he element 2 comprises a base
plate 21 and side walls 22. In this case, the plan is square
and ~herefore there are four side wall8. In -the base plate
21, an aperture 24 is provided. 'rhe aperture is usually
round, but i-t is not limi-ted there-to. 'rhe si~e of -the aper-
ture is considerably larger than -the cross section of -the
concre-te pile -to be used, so that the elemen-t is easily
placed on the pile and its posi-tion can be easily adjusted,
if piles are not located a-t qui-te exact positions on a
straight line. In each of -the two opposite sides of -the
four side walls, an indentation 23 which receives a part of
a pre-fabricated footing block is provided. The width of
the indentation is almos-t the same as -t'he width of the foot-
' ing block to be used. The heig'ht of t'he remaining part of
; 15 the side wall ln which an indentation 23 is provided is
explained later.
T'he pre-fabricated foo-ting block per se is known. It
typically is a long ferroconcrete block comprising a base
- slab and a ridge having an inverted T shape transverse cross
section, this invention is explained with respect to t'his
-typical -type of pre-fabricated foo-ting block, although t'he
' method of this invention is not limited thereto.
Concrete piles are driven into t'he soil by -t'he con-
ventional method at the positions selected according to the
layout of a building to be constructed. After they have
been driven into the soil, a small portion of eac'h pile re~
mains above the ground level. But the heig'ht or level of the
remaining tops of the piles are no-t even, as mentioned before.
Along the lines connecting the piles according to the
' 30 designed layout, trenc'hes are dug, and rubble and gravel are -
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placed in -the trenches an~ leveled so a~ to form the bed for
the footing. The bed may be solidi~`ied by adding mortar or
cement milk. I,eveling elemen-ts such as shown in Fig. 1, for
instance, are placed so t'ha-t their aper-ture~ receive -the top
of -the piles and are orien-ted so that the indentations are
aligned. Fig. 2 shows a leveling element 2 placed on -the
bed 3 so that t'he top of a pile 1 extends upward through -the
aperture 24. '~
Usually, it is impossible to make -the cen-ters of all the
piles exactly accord with the designed center lines of the
continuous footing. As mentioned a'bove, however, the cross
section (diameter) of t'he aperture in -the leveling block is
considerably larger t'han the cross section (diameter) o~ -the
piles. Therefore, the leveling elements can be placed exac-tly
; 15 on t'he designed footing lines. Thus the continuous footing
can be formed exactly in accord with t'he designed layout
regardless of offset in -the cen-ter of t'he pile tops.
After -the leveling elements have been placed, the tops
of the piles ex-tending upward t'hrough the apertures of the
leveling elements are broken so as to expose the rein~orcing
, bars. As shown in Fig. 2, the exposed bars 11 are bent down
; onto t'he surface of -the base plate 21. (It is needless to
say that if the leveling ele~ent is dislocated during t'he
work of breaking -t'he concre-te and bending t'he reinforcing
bars, -the leveling element must be relocated.)
T'hereafter, the reinforcing bars and the leveling
-~ element are fixed by filling mortar, whereby t'he space be-
tween the aperture and the pile is filled.
After all t'he leveling elements have been fixed, pre-
fabrica-ted footing blocks are placed in the trenches so tha-t
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each block bridges -two leveling elements with -the end being
received in an indenta-tion -thereof as shown in Figs. 3 and 4.
~he blocks are fixed to t'he leveling elements by filling
mortar in -the space between -the block and the side walls of
-the level:;ng elements. (F`ig. 4 s'hows the state in which
said space is not ye-t filled with t'he mor-tar.)
The method for compacting the bed under the footing
blocks described in the copending application No.
can be applied to ~the method of -t'his invention. Although
it is not prac-tical, it is possible to lay the footing blocks
without leveling the ballast bed, and to finish the top
surface of the formed continuous footing so as -to level it.
T'he leveling elemen-t shown in Fig. 1 is used for con-
, necting pre-fabricated footing blocks in a straight line.
The leveling element shown in Figs. 5 and 6 is used for ~
junction. In the embodiment of Fig. 5, inden-tations 23 are
provided in t'hree side walls in a rectangular element. In
the embodiment of Fig. 4, the plan of the base pla-te 21 is
a T shape, and indentations are provided in the three end
walls. This element covers a larger area than the embodimen-t
of Fig. 3. T'he leveling elemen-t s'hown in Fig. 7 is for a !,
cross junction. In this embodiment, indentations are pro-
vided in -t'he end of t'he cross bars. Ot'her various shapes
are employable, a square leveling element wit'h an indentation
2~ in eac'h of t'he two adjoining side walls, a ~quare leveling
element with an indentation in eao'h o~ t'he three side walls,
, a square leveling element wit'h an indentation in each side
', wallsl etc. It is self-explanatory from the above explanation~'
that the heig'ht of the remaining part of the side wall in which ~,
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~ 3 an indentation is provided must be larger than t'he thickness
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of the bunclle of -the bent-down reinforcin~ bars. Other
dimensions will be easily determined by -those skilled in
the art.
The leveling elemen-ts of this invention can be easily
manufac-tured by those skilled in the art by the conventional
art with the conventional ma-terials and therefore -there is
no necessity to explain how to manufacture it in detail.
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