Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This invention relate~ to a cable manhole structure
which includç a base, a top, cable lead-ins provided at
least at end walls of the manhole structure, and a
manhole access opening in the top.
In the cable manhole structure disclQsed in German
Early ~isclosure 19 23 6~1, referred to and forming a
part of the disclosure of Canadian Patent No. 1 162 751
issued Fehruary 28, 1984 to Klaus Kohler, the top and
basç are described as monolithic and are divided into
end sections provided with the cable lead-ins, and
extensions connected between the end sections. The
parting lines extended into the contact ~urface between
the top and ba~e parts and were aligned with each other.
The ~trength of that manhole ~tructure was adver~ely
affected by the parting line~ ~nd considerAble ~tre~se~
arose in the means which connected the part~ of the
manhole structure, .~o that increasing loads,
particularly after a certain time, resulted in a fatigue
of interposed seals. In this way, water entered the
structure and the manhole structure consequently became
loose.
German Early Disclosure 19 28 723, also referred to
and forming Q part of thç di~clo~ure of Canadian Patçnt
No. 1 162 751 issued February 28, 1984 to Klaus Kohler,
disclosed a cable manhole structure having monolithic
ba~e and top parts ~nd a plurality of monolithic
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intermediate ring~ disposed bçtween the ba.~e and top
part~. The parting lines were parallel to the contact,
surface hetwçen the top and base part~, or constituted
suçh contact surfaces, but did not open into such
contact ~urface at an acute angle or at right angle~.
That invention al~o included an elongated cable
manhole structure, in which the base and top were tub-
like and were adapted to he placed one on the other nt
their open sides. The hase consisted of at lea~t two
section~. That deæign provided for A con.giderahle
subdivision but gave rise to problem which related to
the t,hreading of the cable into or above component~ of
the manhole structure and nlso influenced the ~trength
of the structure.
CAnadi~n Patent No. 1 162 751 i~ued Febru~ry 28,
1~84 to Klau.~ Kohler purported to provide ~uch a c~ble
manhole ~tructure in which the parting line~ in the ba~e
and top part~ extended in different parallel section
planes of the manhole structure and/or in different
directions and included the provi~ion of tubular strut~
for aligning ~nd al~o provided connecting means between
adjacent sections at the abutting ~urfaces, which are
formed with grooves.
The advant~ge alleged for such structure wa~ thnt
the divi~ion of the parts into ~ections facilitated the
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tran.sportatlon of the prefabricated components of the
cahle manhole structllrç. The arrangement of the parting
- line.s was said to reæult in a high strength of the
rçsulting aææembly, such strength is most important for
cable manhole structllre.s. If parting lines extended
continuously in a plane, it was said that the ~tresses
on the connecting means would be increased. This could
result in a loosening of and would cauæe interposed
æealing materials to f~tigue earlier at some point~ than
~t others. Alternatively, it w~s æAid thAt the f~ct
that the known m~nhole structures had continuou.s,
aligned parting lineæ in its base and top part~ could
result in an expAnsion and in d~mage to the ætructure.
U.S. Patent 4,005,253 pAtented JAnuary 25, 1977 by
B.W, Walker provided a grade level enclosure for
electric~l ~pparatus. It included A hollow open~ended
concrete lower box and an open bottom fibreglass cover
for the box. The wAlls of the cover were horizontAlly
offset At their lower edge portions to form first a
horizontal ledge and then a depending verticAl skirt.
The cover waæ detachably secured to the box by hinge
devices. However the proklem of le~kage At the
interface ~etween the lower box ~nd the fibreglAs.s cover
WAS not ~ddres~ed.
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It, WA.S propo~ed to overcome such problem by the
provision of a sealing gasket bçtween the vertically
~paced-apart,, mutually-opposed parting surfaces of the
base and the top. However this was not completely
sati.sf~ctory. In t,he north and south temperate zones,
freezing/thnwing cycles of moisture in the soil caused
sepAration of the gasket and introduction of ~oil
therein, which prevented a liquid-tight seal from being
established. In other temperAture zones, continued
movement of the soil likewi.se enabled the introduction
of soil between the ba.se and the top and prevented A
liquid-tight seal between the ba~e and the top.
Applicant is aware of Canadian Patent 686 337
i.~sued May 12, 1~64 to R.W. ~odley which shows a
floating roof con~truction in which, to prevent v~por
lo~, a sealing arr~ngement i~ ~upported from the
float,ing roof ~o as frictionally to eng~ge the ~hell
irrespective of the position of the flo~ting roof within
the tank. However, as will be App~rent from the
following disclosure, this structure does not foreshAdow
applicant's com~ination of the gasket And peripheral
side walls of the bAse and top of a cable manhole.
Applicant is also aware of numerous patents
directed to nail-receiving ~nchoring or tying device~
AssociAted with concrete structures, among them, the
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following Canadian Patents 665,675, 1,079,993, 1,073,938, and
1,112,468, and ~S Patents 1,933,536, 2,165,882, 3,514,917,
3,7a8,080, 3,810,339, and 3,949,531. However these structures do
not foreshadow applicant's combination of gasket and peripheral
side wall of the base of a cable manhole.
Accordingly it is a principle object of this invention to
provide an improved cable manhole or box culvert of the above
type in which the t~nding of the liquid-tight seal between the
ba~e and the top to be broken with time is greatly minimized.
lo An object of another aspect of this invention is to provide
a gasket for securement between a base and a top of a cable
manhole or box culvert to provide a liquid-tight seal between the
base and the top.
By one broad aspect of this invention a cable manhole or box
culvert i9 provided comprising: a ba~e including a) a base
including a female inset portion, the female inset portion
including a peripheral ledge and an inwardly-offqet peripheral
wall; b) a top including a peripheral inner wall facing, and
being adapted to mate with, the female inset portion of the base;
c) an insert formed within the inwardly-offset peripheral wall of
the base, the insert being adapted to receive and secure a nail;
and d) a resilient, solid gasket, one portion thereof being
adhesively ~ecured to the inwardly-offset peripheral wall of the
base and another portion thereof being nailably ~ecured to the
insert, the transverse cross-section of the gasket having: (i) a
flat rear face in which an upper portion thereof i3 provided with
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a plurality of vertically spaced-apart, horizontal ribs; (ii) a
front face, in which the upper and lower portions are parallel
with the rear face, and in which the mid-portion is provided with r
a flexibly-deformable, generally-triangular protruberance, the
protruberance terminating in an overhanging cantelevered section;
and ~iii) a foot section interconnecting the cantelevered section
and the rear face; whereby an exposed projecting face of the
resilient gasket is urged into sealing engagement with the facing
peripheral inner wall of the top, when the top and the base are
10as~embled
The base and the top preferably are each made of steel-
reinforced concrete.
It is preferred that the "nailable" member be cast-in-situ
in the inwardly offset peripheral wall of the base, especially
where the "nailable" member comprises a wooden member. Prefera-
bly the opposed faces of the base and the top are generally
~imilar. The cable manhole or box culvert preferably includes a
tie band enveloping the resilient gasket, the tie band and the
ga~ket being nailed to the peripheral member.
The foot section of the resilient gasket rests on the
stepped peripheral ledge of the base, and wherein the resilient
gasket i~ both adhesively secured to the peripheral member and to
the inwardly-offset peripheral wall, and is nailed to the peri-
pheral member.
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By another aspect of this invention, a gasket is provided
for use in forming a fluid-tight seal between vertically facing
walls of a base and a top of a cable manhole or box culvert, and
sealing the space between the two facing walls, the transverse
cross-section of the gasket having: (i) a flat rear face in which
an upper portion thereof is provided with a plurality of
vertically spaced-apart, horizontal ribs; ~ii) a front face, in
which the upper and lower portions thereof are parallel with the
rear face, and in which the mid-portion thereof is provided with
10 a flexibly, deformable, generally-triangular, protruberance
terminating in an overhanging cantelevered section; and ~c) a
foot section interconnecting the cantelevered section and the
rear face.
The ga~ket preferably includes an inset section of the front
face to accommodate a tie band. It also preferably includes an
upper sloping roof connecting the front face and the rear face
and a flat foot interconnecting the cantelevered section and the
rear face.
In the accompanying drawings,
Figure 1 is a perspective view of the cable manhole or box
culvert ~tructure according to broad principles of thi4 invention
~howing the base and the top separated;
Figure 2 is a top plan view of the base of the cable manhole
structure according to broad principles of this invention;
Figure 3 i~ an exploded view based upon a section along the
line III - III of Figure l; and
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Figure 4 is an enlarged transverse cross-sectional view of
the gasket of an aspect of this invention.
As seen in Figure 1, the cable manhole 10 includes a base
11, top 12, an access manhole 13 and conventional cable lead-ins
14, 15. Both the base 11 and top 12 are preferably formed of
steel-reinforced concrete.
As seen in Figure 2, the base 11 includes four walls 21, 22,
10 23, 24, a floor 25 and an upper, peripheral face 26. ~t also
includes a lower peripheral ledge 27. In addition, it includes
a stepped, inset ledge 28 providing an inwardly-offset peripheral
wall 29. A peripheral nailing strip 37 (to be described in
greater detail hereinafter) is cast into place within peripheral
wall 29 during the manufacture of the concrete base 11.
As seen in Figure 3, the base 11 includes an inner side
wall, 31, and an outer side wall 32. The upper peripheral face
26 has an arcuately curved nose 34 leading downwardly to
inwardly-offset, peripheral wall 29, which terminates in a
stepped inset ledge 28. Then the outer side wall 36 continues
downwardly from ledge 28 and curves outwardly at 33 to form lower
peripheral ledge 27 which meets the outer side wall 32.
Disposed within the inwardly-offset peripheral wall 29 is
a peripheral "nailable" strip 37, shown in the
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form nf a trapezQidally-~haped (in cro.ss-æection~ piece
of wood, although any equivalent metal or pla~tic
nailable ~trip or member çapable of acçepting a
fa~tener, ç.g. a .sçrew may be usçd. The expo.qed face 38
of nailable strip 37 iæ flush with the front face of
inwardly-off~et peripheral wall 29.
The ga.~ket 40 i.~ ~eçursd to the inwardly-off.~et
periphçral wall 29 hy an adhesive, e.g., an epoxy glue,
aq well A~ by a najl 41. It i.s preferred (as shown)
that a retaining hand 39, e.g., of a synthetic plaqtic
material, i.e. nylon, be wrapped around the gasket 40
prior to the ~écurement hy mean.~ of the nailing step.
The top 12 includes an inner side wall 45, and an
outer side wall 46. Inner side wall progre~e~ by means
of outwArdly directed roof 47 to inner arcuate fnce
48 and downwardly to peripheral inner faclng wall 49,
to extend hy curved face 50 to lower roof .51 which meets
outer .~ide wall 46.
In US~, the top 12 iq placed on the base 11, so
that the gasket 40 provideds a liquid-tight seal between
the opposed peripheral faces 29, 36 of the botton 11 and
face 49 of the top 12.
Figure 4 .qhowq the structure of the ga~ket 40. It
include~ a rear face 61, and a front face 62. Rçar face
61 i~ provided, at it~ upper portion with A plllrAlity of
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vertically-~pa~ed-apart horizontal rib~ 63. Front fa~e
62 i~ provi.ded with an in.qet portion 64 and an upwardly
~loping face 65 which i.~ ~onnected to rear fase 61.
Front face 62 al.qo includeq an outwardly-project.ing
ledge 66 and a downwardly and outwardly ext.ending
protruheran~e 67 whi~h overhangq a çantelevered lower
fa~e 68. The lower portion 69 the front face 62 mergeq
with the lower portion of the rear face 61 at ha~e 70.
Ga~ket 40 i.q preferahly Gast from a reqiliently
deformahle material, e.g. a .qynthetic ruhher.
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