Note: Descriptions are shown in the official language in which they were submitted.
~1338~
~I~{ING ~YIEANS ~O~ CONNEC~ING COM:PON~NTS
BACK~EIOIJND O~ ~3 INVENTION
Field o~ the Invention
Thi~ invention relate3 to fixing me3~ or
connecting component~, particularly prefabricated
concrete member~ or tubbing ~tone~ 9 w~lich means comprise
a plurality of pluglike anchor~ 9 which are adapted to be
forced with ela~tic deformatio~ into arlchor hole3, w~ich
are i~ormed in ~aid co~nponsnt3 a~d open in confronting
sur~ace~ o~ ~aid component ~, ~o that the ~lChOr8 ar0
frictionally held in and/or po~itively locked in the
anchor holes.
De~cription o~ the Prior Art
~ ixi~ me~ of that kind are u~ed, e.g9,
in the co~Ytruction of tunrlel 1 ;n;n,g~ to COl:lrLeC~ the
~ubbing ~tone~ or other ri~g eleme~$~, a~d may ~u~titu~e
conventional ~crew Ia~tener3, which are expen~i~e and ca
be used only with dif~iculty and i~volYe a wepken; r~g o~
the material. ~he anchors may be mount~d be~ore a ~e~v
~tone i3 in~tall~d 90 that the a~chor~ may be usad al~o
to align an additior~al component with previously placed
components ~o that a modular as~ambly o~ the component~
ca~ be obtained~ Other ~ield~ o~ applica~ion o~ fixing
means o~ the preoent kind are joints between relatively
large structural component~, ~uch as pre~abricated
concrete elements, in bl~i 1 (li n~ construction and civil
~ng1 neering.
From EP-A-100 771 it i~ knoml to COIlrleGt
tubbing stone~ by mealls o~ sleevelike li~er~, which
are in~erted into anchor holes and made o~ rubber-ela~tic
or ot}ler ela~tically deformable material and havs holes
~3~37~
Z
which flare conically near and toward the outer end o~
the ~leeve but are cylindrical elsewhere. Anchor~ are
employed which con~ist of cylindrical metal rod3, which
have pointed en~ and are ~ir~t drive~ i~to the anchor
hole~ of one stone and a~ the stones are engaged with
each other are in~erted into the li~er~ o~ the prsviously
placed stone~ The in~ide diameter of the cylindrical
holes o~ the liner~ iY smaller than the out~ide diameter
of the mstal rod~ so that said metal rod~ are in~erted
into the liners with ela~tic de~ormation and are
~rictionally retained therein. ~he slastic deformability
of the ~leevelike li~ers i3 inte~ded to ef~ec~ a
correction o~ any mi~ nment of the axe~ o~ the
metal rod~ and the axe~ of the a~sociated anchor
hole~,
D~-A-22 38 792 provide~ for connecting
platelike 3egment8 by fixing mean~ ~hich co~si~t
of ~leeves~ which are in~erted into one compbne~t~
and anchor bolt~, ~hich are fixed to the other c~o~ponent.
Spring tongues are secured to the sleeve and ~L G~ 4Q ~
from the open free end o~ the ~leeve . 5aid ~pri~ tsngu~s
are d~flected and clamp the bolt a~ it i~ scrtad - i~bo
the ~leeve 80 that a frictional con~aot i~ achi~ed.
EP-A-114 514 disclo~e~ ~imilar fixing mean~ for co~-
necting tubbing stones.
D~ A-24 57 427 discloses fixing meaIl~ which
are of the kind de~cribed first hereinbe~ore a~d
comprise an a~chor consi~ting o~ a steel bolt havi~g
in cros~-sectioll a sawtoothlike external ~hape bu~
uniform crest ~d root diameter~. ~hat steol bolt
is adapted to be forced into a liner~ ~Nhich has bea~
(3 3 7 l~
insert~d into the anchor hole and is made o~ rubber-
elastic material and has on th2 out~ide a mating or
corrugated shape in cros~-~ection.
All _~ewn fixing mean~ of the pre~ent kind
have the disadvantage that ~eparats liners made, e.g.,
of rubber-ela~tic material mu~ be inserted into the
a~chor holes in mo~t ca~es ~o that the ma~u~acture o~
the component3 i~ dif~icult. If the anchor a~d the
liner in the anchor hole have corre~pon~in~ shapes
in cross-sectio~, the re~tr~;n;ng ~orce wqll not bP
~uffic~ently large and ~rom the beginnin~ o~ the
insertion of the anchor into the liner it is necessary
to overcome the re~istance of the li~er to deformation
until the anchor has been i~erted as ~ar as i9 required.
I~ somc design3 that resi~ta~ce to deformation progre~D
sively increases as that i~3ertio~ proceed~. ~articul~rly
at the beginn; ng of the in~ertion the anchor will be
~ubjected to a high bl~ckling load and thi~ mu~t be
taken into account in the selection o~ ths cros~ ~ectio~al
areas. Whsre ~ixing mea~8 which establi~h only a
re~tr~.~ ni ng frictional engagament are amploysd, ~he
driving forces required and the restr~in;ne force~
will not axactly be dafined owing to the mQnu~acturing
tolerance30 Similar remark~ are applicable ~or a fi~atio~
by means o~ deflectable 3prin~ tongue~.
Summar~ o~ the Invention
It is an obàect o~ the invention to provide
fixing means which are o~ the kind described ~ir~t
hereinbefore and are simple in de~ign and particularly
have simple anchor holes and ~er~it ~trong and de~inable
restr~i n; ng force~ to be exerted on the anchors~
'~3~,~7l~
lt is another ~oject of the invention to
prcvide ~i~ino ~e2ns in l~hich th~ 2nchnrs can be more
easily be inserted inta the anchor holes anri the forces
requirod t3 overcame the resistanc2 to deformation need
to be ~xErted only durin~ _ fractional oart oF the disolace-
ment of each anchor as it a inserted, ond which ensure that
each anchor will reliably reach the required position in
the anchor hole 50 -that, e.n., sealinn inserts provide~
between tha comoonents to 'e connecteo will reliably be
subjected to the reouired initial stress.
The first object stated hereinbefore is
accomolished in that the anchors are substantially stiff
and have a oerioheral surface which at least in oortions
intended for a retaining engaqement with the inside surface
o~ the anchor hole is ~esi~ned to be elastically deformable
at least in an apDroximately radial direction.
The basic concept cf the invention resides in
that the elastically deformable means which are required
to exert the restraining forces are provided on the
anchor and the anchor is designed to have in its axial
direction a suFficiently hioh stiffness so that the
anchor can be inserted without diFficulty into the
associated anchor hole.
The peripheral surFace of the anchor may con-
sist oF a plastic material which has entropy elasticity.
~ winq to the use of a plastic material
which has entropy elasticity the insertion of the
anchor is racilitated and the retaining force exerted
by and on the anchor which has been inserted is in-
creased. The term entropy el3sticity describes a fluw
behavior which is exhibited by plastics when aFter an
~lastic deformation they tend ';o assume their initial
2~3~
shaoe bv creYn ~o~e~ents or when under the action oF
actual oressure fnrces the\! tenrl to ~low into regiDnS
which are under a lower pressure load at that ti~e so
that the oontact pres~ure forcrs will suostantially be
euqalized when the flow orocess has terminated. In the
oresent c3se that Flow beha~ior ran be u-tilized in that
the deformable Peripheral oortions of the anchor are
somoressed by ~eans of separate aODaratUseS or in
constricted portions of t~e anchor holes and/or to
displace said deformable oortions in the lanoitudinal
~irection of the anchor. I~lhen the anchor has been
inserted into -the anchor hole to the required extent,
portions of the elasticallv defor~ed zones will flow
into recesses formed in the inside surfaces of the
anchor hole so that a positive and frictional anchorino
will be o~tained. ~ substantial anchoring action will be
achieved even in anchor holes havinq a rouoh inside
surface of concrete if, in the simplest case, sub~
stantially cylindrical anchor holes are orovided as
well as corresponding anchors which have elastically
deformable zones which are larger in diameter than
the adjacent zones of the holes. The anchoring action
can substantially be increased by further measures,
e.g., by the provision of undercuts in the inside
surface af the anchor hole.
Surprisingly it has been found that a se-
lection of proper materials will permit satisfactory re-
sults to be produced even if the oeripheral surface of
the anchor consists of wood, particularly of soft wood,
if that wood is so arranged that its fibers extend sub-
stantially in the longitudinal direction of the anchor.
Fir and spruce are preferably emoloyed as soft woods,
which have a much hioher sitffness in the longitudinal
direction of the fibers and have a hioh modulus of
~3~3 ~
elasticitv ~;ransversely to t~le ~irection of the lbers
so that their retaininn oraoerties are similar to those
af the above-~entiorlod alastic ~aterial. T~e entire anchor
~ay consist nf a l)oo~en aart in l~nich the Fibers extend
in the lonnitudinal direction 5f the anchor and l~hich has
been i~nreanated to rasist an inoress nf ~oisture and
outrefaction. The wooden oart may be made in one oiece
or may consist of a oluralit\/ of element.s "~Ihich have
been 'oined e.n. with olue and have then been oiven their
final shape. Reinforce~ents and inserts such as will be
mentioned hereinafter ~ay be nrovided also in a wooden
part.
In a preferred embo~iment each anchor is
formed in that portion ~.~hich is to be inserted into one
of the anchor holes with two or more retaining zones
for enoaging the i.nsirle surface of the anchor hole. It
will oe particularly desirable if the average diameters
of the retaining zones of the anchors and of the anchor
holes consecutively increase from one retaining zone.
It l~ill be particularly desirable if the average dia-
meters of the retainino zones of the anchors and o
the anchor holes cnnsecutively increase from one
retaining zone to the next in the direction extending
away frorn the inner end of the anchor and anchor hole.
2~3~3~
Tha provision of stepped anchors and anchor
hole~ has the reRult that the deforming ~orce to be
exerted for a frictional and/or po3itive restr~ining
engagement wqll have to be exertsd only in the region
in which a sociated re~trainin~ zone~ of the anchor or
anchor hole engage each other, i.e~ only toward ths
termination of the insertion of the anchor into the
anchor hole and duri~g a correspon~; n~ fraction~l
part of the di~placement by which the anchor i9 in~erted
into the ~chor hole and it will ba nece~ary to e~:ert
that force o~ly when the ~chor i~ already s~icien~ly
guided in the anohor holeO ~hat g~ ce will be improYed
by the f~ct that buckling load~ on the ~nchor will
substa~tially be avoidsd in all retaini ng zc~ne8 a~ld
excessive loads will be avoided ~v~n ~ha~ the anchor
and tha anchor hole are ~ot exactly ~ ned duri~g
the a~emblin~ operationO On the contrary, the anchor
will strictly act a~ a g~Aiding element during a major
part of the displacsment by which the anchor hole i8
inserted into the a~sociated ~chor holeO
Within the ba~ic desig~ provided in accordaac~
with the invention, various ~ariation~ in detail mag be
adopted. In a pre~srred embodiment the reta;n;ng zone~
of the anchor are ba~ically cylindrical or have a ~lender
conical ~hape increasing in thi ckne~8 to~ard the end o~
the a~chor that i~ to be inserted into the ~nchor hole.
Oonical transition portions may be provided bet~en thc
ret~ining zonss. The 31ender conical shape which
increaqe~ in thickne~ toward the free end o~ th~
anchor ~ill improve t~e retention oi the a~chor in
the anchor hole.
~3~3~7~
An em~odiment may be adopted in ~hich the
anchor i~ provided in the ret~inin~ zones with Annl~le~
pads ~ich are made of a material which i~ more ea~ily
de~ormable and has a higher coefficient of ~riction than
the remaining ~nchor material~
- In accordance with a further preferred feature
the ~nnl]l~ pad~ are inserted in ~nnl~l er groove~ which
are provided on the peripheral ~urface o~ the anchor and
have in axial 3ection a sawtooth ~hape having sloping
tooth ~ide faces ri~ing toward the i~ner end o~ tha
anchor. When a force ten~i n~ to pull the anchor out
o~ the anchor hole i~ exerted on the a~chor, ~aid
~loping ~ide ~ace3 will tend to ef~ec~ an exp~nAing
deformation of the pad, which ha~ a~ out~ia~ sur~ace
in contact with the inside ~ur~ace o~ the allchor hole3
~o that the contact presflure exerted by the pad o~ th~-
surface o~ the hole and the sd~e~i~re force will be
increa~ed .
In a different embodiment~ comh~ nnnl ~r~
pro jection~ are provided i~ ~8ch rete;n;n~ zolle~- o~ he::
anchor hole and a~ leasl; on that side which faces :ths;
inner end o~ the anchor hole de~i~e uIldercut~ a~d ha~e
an in~ide diameter that i~ sm~ller tha~ the out~ide
diauneter of the a~chor in the a~sociated ~one. That
design may be adopted for u~e with an anchor wh~ch
ca~ be elastically deformed at lea3t in part and
will have the result that u~en a ret~nine zon.e o~
the a~chor has been f'orced past the annular projection
the matarial of that zone will flow into ths u~dercu~
~o that the anchoring will be imprcvcd~, ~he pro~ection~
in the anchor hole may c0~9i~t 0~ annular in~ert~ of
metal which are held in ths concreteO ~n order to
2~3~3~
_ 9
increa3a the size of the undercuts providsd behind ~aid
armular inserts? ela~tically deformable or detachable
in~erts may be proYided un ths x ear o~ the rings be*ore
the concrete i9 ca9t .
In a ~urther embodiment the anchor~ are made
of pla~tic and provided wit;h a metal rein~oroement. ~he
a~chors ca~ speci~ically be made OI polyamide, polye~h-
ylene and polypropylexle a~d the rein~orcement~ ~re:~erably
consist of iron or ~teel. Alter~atively~ me~h rein~orce
ments may be provided or the core8 of the ~chor~ may be
made o~ plastic reinforced with glass ~lber~. The
distribution o~ the total stress to the plasl;ie a~d
reini~orcement will be detiermined in ~riew o~ the severity
o~ the u~age ~ the required li~e arLd the requirsd strength .,
pre~erred embodimen~ the reini~orce~e~t co~ist~ o~ a
lo~gitl~;n~l tubet which is embedded in the pla~ti¢ and
which is provided on the outside with ret~in;ng ring~
which are embedded i~ the plastic material at the ends
of e~ch retai ni ng zoneO I~ that ca~e the plastic
mater~al will be backed by a ring adjacent to aach
retQ; n; ~ zone ~o that the de~ormi~g forc~s t~ be
exerted for the ~ixation a~d ths ret~ining foroe~
e~erted by and o~ the in~talled anchor will be applied
in a d2sirabl~ r~nner.
~ he as~embling may b~ facilita~ed in that each
anchor ha~ conically tapered end portion~ and each a~chor
hole may conically flare from the con~ronting ~urface~ of
the component~ to the neare~t retai n; ng zone 0~ the
anchor hole.
Further details and advan~age~ o~ the inve~tio~
will become apparent from the sub~equent de~¢ription o~
the drawing.
2~3~37~
Brief Description o~ the Drawin~
Figure 1 is a fragmentary ~ectional ViQW
~howing a portion of a concrete member formed with
an anchor hole together with an aachor which ha~ one
half that ha~ been inserted into ~aid hole and another
half intended to be ~ecured to another concrete m~mber~
Two different anehor embodiment~ are ~hown in the two
halves of Figure 1.
Figure 2 is an enlarged axial sectional vie~
~howing as a detail a retaining portio~ o~ the anchor.
~ igure 3 iY a view which correspond~ to th~
left-hand half of ~igure 1 a~d show~ a diff2re~t ~i~in~
device.
Figure 4 i9 a fragmentary sectional view
showing the anchor of the fixi~g deviae o~ Figure 3
in an undeformed 3tate.
Figure 5 is a view which also oorre~p~nd~
to the left-hand half of Figure 1 ~d ~how~ a fu~her:
fixing device.
Detailed Description o~ the Preferred ~mbodime~
The invention i9 illustrated by way of example
o~ the drawings.
In accordance with Figure~ 1 and 2, two
concrete member~ which are to be conncctQd and eo~i~t,
e.g., of tubbi~g stones a~sociated with r~peatlve ri~g~
are formed on con~ronting end ~ace~ 1 with 3pace~ ~part
~ ~ 3 ~?~
a~chor holes 2~ In the illustra~2d embodiment~ each of
3aid a~chor holes compri~e~ three longit~ n~lly ~ nedt
cylindrical retai ni n~ zons~ 3J 4~ 5 9 which increa~e in
diameter from the bottom 6 of the hole 2 toward the end
face 1. A cQnical flaring portion 7 i~ provided in the
hole 2 between the outermo~t retaining zone 5 and the
end face 1.
A plllgl i ke a~chor 8 comprise~ two arlchor
heads 10, 11, which e~ctel~d from a tubular intermediate
member 9 and are normally iden~ical. ~ach a~chor
head 10, 11 ha~ a conica1 end portion 12 and has
retQining zones 13~ 14, 15 Yvhich are axiallg arrar~ed
like the ret~inin~ zone~ 3, 49 5 of the a~chor hole 2.
A3 is particularly apparerlt ~rom Figure 2 t:be a~chor 8
i~ provided adjacent to each o~ the ret~.;n~ng zons~ 13
to 15 with ~nnl~l~r pads 16~, ~ich cox~i~t o~ a matarial
that has a high coefficis~t of friction a~d is mor9
easily de~ormable than the rem~inin~ material. o~ the
anehor. Said ~nn~ pad~ extend in ~nn~ r groova~
formed on the periphery of the anchor~ ~I!he bottom o~
ea~h of ~aid groove~ ha~ a multitooth sa~tooth pro~ile 17
in axial 9ect:~0n. ~he slopi~g ~id~ ~ace~ o~ ~aid teeth
rise toward the inn~r end o~ the anchor 90 tha~ a pl~ ng
force exerted orl the anchor head 10 arld ten~?1ng to pull
it out of th~ anehor hole ~ will cau~e the loping to~th
~ide ~aoes 17 to force radially outwardly the ma~erial 16
w~ich is ir~ frictional contact with the in~ide ~urfaea o~
the ancho~ hole whereby the corltact pre~ure applied to
the in~ide ~ aee of the hole will be inerea~ed i~ ea~h
of the engaging zone ~ 3, 4, alld 5 .
In the embod~ment shown on the ls~t in ~ig~e 1
a major part o~ the a~chor head 10 con~:Lste o~ plastle
-- 12 --
and is provided with a rein~orcing insert consi~ting o~ a
perforate~ tube 18.
In the embodim0nt ~hown on the right in
Figurc 1 the anchor comprise~ an i~ner tu~e 199 which
carrie~ ret~inin~ ring~ 20, 21, 22, 23 adjacent ~o the
ends of the retaining zone~ 13, 14 and 15. Said retaining
rings 20, 21, 22~ 23 are embedded in the plastic
material 24 which con~titutes the ~hell of an an~hor.
In the embodiment shown in Figure~ 3 and 4
the anchor hole 2~ i~ al~o ~ormed with con~cutive
ret~.inin~ zone~ 3a9 4a, 5a and the anchor head 10a
of the anchor 9at 1Oa i~ alYo provided with retain; n~
zones 13a~ 14a, 15a, which dif~er in diameter. ~he body
of the anchor 9a, 10a consi~t~ of a plastic material
which is ela3tical1y daformabls to a limited e~ L:
and whioh is optionally rei~forc2d by gla~ fiber~.
Within the length o~ each o~ the ret~jning zo~c~3a~
4a ~nd 5a of t~e anchor hole 2a, conce~tric ring~ 24,
25 and 26 are ins~rted i~to the in~ide ~urfac~ of the
anchor hole ~d each of 9aia riYlg~ has a~ inner~r~
v~hich i~ ~maller in di~ter tha~ tha out~ide diam~-*er:
of the a~ociated retai n; ng zone 1 3a, 1 4a or 1 5a of the
arlchor. On that ~ide of each of th~ rings 24, 25 ,, 26
which is n~arer to the outer end of t:hs ~chor hol~ 2a9
the inside sur~'ace o~ the anchor hole 2a i9 ~ormed ~rith
an :Inm7- ~r ra~p ~urface 27. Said insido ~urIace o~ the
a~chor hole 2a i~ ~ormed o~ the opposite side oi~: each
ring 24b, 25b and 26b with an ~ular surfac~ 28, which
is radially o~ dly of~set Irom the iImar rim o~ the
adjacent ring 24, 25 or 26 to form a recoss thereO I~
order to form ~aid annular surface~ 28, an ela~ti~ally
de~ormable, easily deformable or remo~able ring may bs
: .
' 3 ~ ~
-- 13 --
in3erted be~ide each of the metal rings 24, 25 ~d 26
be:eore the casti~ of the concrete used to make the
concre-te memb~r formed with thQ a~chox hole 2a. A~
is ~pparent from Figure 3 the in~ertion of the a2lchor 9a,
10a irlto the a~chor hole 2a cause~ the ma~erial of the
zones 13~, 14a, 15a to flow radially outwardly a~ far
as to the adjacen~ ~nn~ r ~urface 28 ~o that th~
pll~l i ke anchor will be po~itively a;tld frictiorlally
held in the anchor hole 2a.
In accordarlce with ~igure 5 the anchor
hole 2a compri~es collsecutive retai~i~g zone~ 3bp 4b" 5b
and i~ provided with ri~g~ 24b, 25bt 26b corr~pon~;n~ to
the rings 24 to 26 o~ Figure 3. Axially ;~ ly o~ each
ring 24b9 25bp 26b the in~ide ~urface of the anchor
holQ 2b is formed i~ ths a~ociated zo~e 3b, 4b, 5b
with ~1 s~nn~ r ~Lrface which i~ radially oul~ d~y
off3et ~rom the inner rim of the adjaoe~t ring 24b,
25b, 26b. Adjacent to the ret~1ning zo~e~ the body
of the a~chor head 10b i9 ~ormed wi~h ~nn~ grO0ve8 29
30, 31, ~hich have a ~awtooth-ahaped pro~ile i~ axial
3ection and in which pla~tio ri~g~ are embedd~d, ~hi~ch
c0~9i8t of a plastic material that ha~ a relati~ely high
coe~ficient of ~riction and a relatively high entropy
elasticity. ~he plastic rings are ds~i~n~t@d 32, 33, 34.
In that case too the i~ertion of the a~chor hsad 10b
into the ~nGhor hole 2b will cause the material of bh~
ri~g~ 32, 33, 34 to flow behind th~ ring~ Z4b, 25b9 26b
r~ y outwardly as ~ar a~ to the radially outwardly
off~et ~nn~ r ~urface90
2 ~f 3 iJ 3 7 l~
- lL~ -
In all am~o~i~ents shown in the ~rawirlgs, the
intermediate ~ember orovided hetween the anchor heads 10 and
11 of anchors used to connect the same rinn ~a~/ ~iFfer in
l2ngth, Fo~ ~nstance, in or~er to prn~ e we~ae-shaoed gaos
between consecutive tubbinq l~inns of the same annular
assembly so that the tunn~l lininq ~ay extend along an arc.
The elements 19, 11, an~ 10 and the correspond
ing elements 9a, 10a, 10b and 29 are marle of a plastic ma-
terial which has entrooy elasticity. Such plastic material
in which the molecular structure oF the polymer permits
the material to exoand within certain limits after the ma-
terial has been compressed. The material i5 molded by the
so-called reaction injection molding process so that the
isotropic properties of the material are improved. An
example of a suitable material consists of the material
which is known as "Dowel-~dymer" and i9 available from and
has been developed by ~oloplast, Leonding, Austria, in co-
operation with the present inventors.
All embodiments shown can be modified within
the sco~e of the invention in that the illustrated anchor
is replaced by an anchor which has the same exterior shape
and is ~ade of a wood which is so arranged that its fibers
extend in the lon~itudinal direciton of the anchor so that
the forces which are exerted on the anchor as it is fixed
in position will act substantially transversely to the
direction of the fibers. Said wooden parts may consist each
of a plurality of elements, which are joined with glue,
and, ~or instance, in the embodiment shown in Figure 1 the
wooden body may be provided only outside the part 1a and/or
may consist ot annular inserts provided between the rings 2a
to Z3.
~ :" ~ ~
.
