FR2671119A1 - CONCRETE CONSTRUCTION ELEMENTS, PRE-STRESSED, OF THE PRELABS TYPE, INSTALLATION AND PROCESS FOR THEIR MANUFACTURE. - Google Patents

Abstract

The invention relates to new pre-stressed concrete construction elements of the pre-slab type comprising a thin concrete plate, provided with internal prestressing reinforcements (24), and delimited by a lower face (12), an upper face (14). ), two side edges (16) generally parallel to the frames and two transverse ends. Each of the lateral edges (16) comprises a chamfered lower part (18) molded with the lower face (12) and an inclined upper part (20) shaped by extrusion with the upper face (14). The invention also relates to a method and an installation for the manufacture of such building elements.

Description

4.;> 2671119

  Prestressed concrete construction elements, of the pre-

  The invention relates to prestressed concrete building elements, of the pre-slab type, as well as an installation

  and a process for their manufacture.

  Construction elements of the pre-slab type are surface elements each formed by a thin concrete plate, which is provided with internal reinforcements

  of prestressing and which is delimited by a lower face

  re, an upper face, two lateral edges generally parallel to the direction of the prestressing reinforcements

and two transverse ends.

  We essentially use these construction elements for the manufacture of floors. For this, we have a construction element in its final location within a building and then we pour on this element,

  a layer of concrete, also called "compression table".

  This layer of concrete, once hardened, forms with the building element, that is to say with the pre-slab, a slab

  resistant of greater thickness.

  The manufacture of building elements of the pre-slab type

  is generally carried out in the factory by means of a bench

  both a horizontal manufacturing area, of elongated shape, usually extending over a length of several tens of meters, for example 100 m, and over a width

  generally between 2.5 and 3 m.

  This bench also includes means for energizing

  of prestressing reinforcements parallel to each other

  above the manufacturing area and in the direction lon-

  gitudinal of the latter, as well as a molding device movable in translation along the bench and comprising

  in particular a device for distributing and vibrating concrete on the manufacturing area.

  In manufacturing processes and installations of this type, the concrete is poured in a set of molds, the bottom of which is defined by the manufacturing area and the side walls of which are defined by side edges extending parallel between them along the entire length of the bench, as well as by transverse combs

  and by different rooms of separation and reservation.

  It is thus possible to manufacture, in a single casting operation, construction elements of different types, of shape

  rectangular or not, with or without reservations.

  The prestressing reinforcements being tensioned,

  and after possible installation of additional reinforcement

  shut up, concrete is poured and vibrated in the set of molds thus defined and, after the concrete has hardened and the tension in the reinforcements has been relaxed, the latter are sectioned between the various construction elements thus molded on the manufacturing area. so individual elements. Construction elements of the pre-slab type as well as an installation and a process for their manufacture are known in particular from French Patent No 85 04947 in the name of the Applicant This Patent describes in particular various means making it possible to automate the various operations as much as possible of manufacturing construction elements on

bench.

  In the prior art, construction elements of the pre-slab type were manufactured by pouring on a lower shuttered face, that is to say on the manufacturing area, the latter being provided with lateral edges having at least the thickness of the pre-slab to be made It was therefore necessary to pour a relatively fluid concrete to allow its spreading, even in the case where the concrete was vibrated.

  The slabs thus obtained had a larger surface

  more or less regular and, in the best of cases, the precision of the height or thickness of the pre-slab could not exceed 5 mm, i.e. an accuracy of 10% for

a 5 cm thick pre-slab.

  In addition, in the prior art, the precision of the lateral edges

  les was not always perfect, so there was often a clearance between two juxtaposed slabs, this clearance leading to concrete leaks during the pouring of the

compression table.

  In addition, in the prior art, the end pieces of the slabs were often made with poor precision and

  had burrs, due to the partial structure

  comb of the combs used to form a separation

  transverse between two successive cast elements.

  The object of the invention is in particular to remedy the drawbacks

above mentioned.

  It is, in particular, an object of the invention to provide a building element, of the pre-slab type, of a quality

  overall significantly higher than that of the elements of cons

existing truction.

  It is also an object of the invention to provide such an element

  of construction which can be achieved with great pre-

  cision thus saving concrete, while having performance at least equal to that of the elements of

the prior art.

  It is also an object of the invention to provide such a construction element which has an upper surface of great regularity, lateral edges produced in a very precise manner and transverse ends produced in a precise manner.

  very precise and free of burrs.

  It is also an object of the invention to provide such a construction element which can be produced with a precise thickness by perfectly controlling the height of the concrete during

  of the casting of the building element.

  It is another object of the invention to provide such an element

  construction may have a height or thickness no-

  less than that of known elements, while having the same mechanical performance, due to the precision

  thickness and compactness of concrete.

  The invention also aims to provide an installation and a method for the manufacture of these new elements.

of predalle type construction.

  It is also an object of the invention to provide such a method and such an installation which make it possible to manufacture the construction elements with great precision, while saving concrete, and while retaining the manufacturing flexibility offered by the installation and process

described in the aforementioned patent.

  According to a first aspect, the invention relates to a prestressed concrete construction element, of the pre-slab type, as defined in the introduction, in which each of the lateral edges has a chamfered lower part.

  coming from molding with the underside and a su- part

  inclined edge formed by spinning, and in which the upper face is shaped and precisely leveled

by spinning.

  It is thus possible to produce construction elements having a good quality of appearance owing to the fact that the lower face has come from molding with a part of each of the lateral edges and that the upper face is shaped by spinning,

  as well as the upper part of the lateral banks.

  As this conformation takes place by spinning, a drier concrete can be used which, for equal resistance, can be under-dosed with cement, for example of the order of 10 to

12%.

  The height of the concrete, i.e. the thickness of the element, is perfectly controlled with an accuracy of the order

  1 mm, which avoids excess and wasted concrete.

  The conventional nominal height of 50 mm of the elements of the pre-slab type can thus be reduced to 45 mm with the same mechanical performance, due to the thickness precision.

  and the compactness of the upper face of the element.

  In terms of cost, these gains on concrete can be estimated

about 20%.

  By way of example, the construction elements of the invention

  tion can have a width of 2.50 m for a maximum length of 9 m Their current thickness is 45 mm and

can reach 120 mm.

  According to another characteristic of the invention, the chamfered lower part and the inclined upper part of the lateral edge are connected together by a part

  intermediate substantially perpendicular to the underside

upper and upper side.

  Thus, when two construction elements are juxtaposed by their respective lateral edges, the two chamfered lower parts of the respective lateral edges of the two elements form a chamfered part favoring the attachment of a joint filling product. Similarly, the upper parts two opposite side banks provide another chamfered area which allows the concrete of the compression table to fit perfectly into

the space thus provided.

  In addition, due to the presence of the intermediate part, the two construction elements come perfectly

  in abutment, without leaving play between them.

  According to another characteristic of the invention, the lower face of the element and the lower part of each of the lateral edges thereof are smooth, while the upper face of the element and the upper part of each lateral edge are roughened by parallel streaks. These grooves then facilitate the attachment of the compression slab. Advantageously, the ridges are parallel to the reinforcements

  of prestressing and are more accentuated in the law of these

  this, which then makes it easy to locate the location

  prestressing reinforcements for possible drilling

  ment, carried out from above, of the element on site.

  According to another characteristic of the invention, the construction element comprises flexible lifting cables forming loops and connected to the prestressing frames, these cables

  having button-shaped ends embedded in the thick

  element sor This produces lifting cables that offer better security than fixed hooks

  rigid of the prior art.

  The construction elements of the invention may also include at least one reservation of selected form, in

  depending on the desired application.

  In another aspect, the invention relates to an installation for the manufacture of the construction elements defined above. According to the invention, the manufacturing area is provided with two formwork of banks extending parallel to each other and along the length of the bench for molding the lower parts of the lateral edges of the building elements, and the molding apparatus comprises means for conforming

  by spinning the upper face of each construction element

  tion and means for shaping the parts by spinning

  upper banks of this building element.

  In a preferred embodiment of the invention, the ap-

  similar molding comprises a dispensing device provided with a chassis movable in translation over the length

  of the bench to distribute and vibrate concrete on the manufacturing area

  cation, this distribution device being provided, on its rear part relative to its direction of translation, with a vibrating rule arranged transversely above the manufacturing area and suitable for conforming by spinning

  the upper side of the building elements.

  Advantageously, this vibrating rule comprises a multipli-

  city of vibrating pads arranged adjacent and transverse-

  lying above the manufacturing area, each shoe being provided with a vibrator and being connected, via a release cylinder, to a common cross member carried by the chassis of the distribution device, each of the cylinders of clearance being controllable independently of the 5 others to vertically move the corresponding pad

over a determined height.

  It is thus possible to retract a shoe, independently of the others, if it must meet an obstacle, for example a reinforcement or a lifting cable protruding from the

  upper side of the corresponding building element.

  According to another characteristic of the invention, the vibrating rule comprises a frame carried by the chassis of the dispensing device, the cross member being connected to this frame by means of at least two positioning jacks with vertical actuation capable of ensuring a precise height adjustment of the cross member and pads relative to

to the frame.

  Thanks to these characteristics, you can adjust very precisely

  the thickness of the construction elements being fabricated

tion on the bench.

  According to another characteristic of the invention, the frame of the vibrating rule is connected to the chassis of the device

  distribution via a lifting mechanism

  suitable for moving the frame between a low working position in which the frame is suitable for rolling on two rails along the manufacturing area and the pads are

  suitable for conforming the upper face of the components

  truction, and a high retraction position in which

  the frame is raised at a distance from the manufacturing area.

  Thus, in the working position, the vibrating rule takes

  reference on the aforementioned rails.

  According to another characteristic of the invention, the installation

  tion further includes a finishing device capable of conforming the upper parts of the lateral edges, this device comprising a frame movable in translation along the length of the bench and carrying two finishing members

  symmetrical proper to follow respectively the two safes

riverbanks.

  In a preferred embodiment of the invention, each of the finishing members comprises a cheek carried by a mobile unit and movable between a working position where it is in a substantially vertical position bearing on the top of the edge formwork, and a retracting position where it is raised above the bench, the cheek carrying an adjustable support plate which, in the position

  of the finishing device, is substantially horizontal-

  tale to smooth the edge of the upper face of the element

of construction.

  According to another characteristic of the invention, the frame

  of the finishing device also carries a notched comb

  age suitable for producing, on the upper face of a building element, grooves extending in the direction

longitudinal of the bench.

  It will be understood that the vibrating rule of the distribution device

  bution first ensures the conformation of the upper face of the construction elements and that the finishing device then ensures the conformation of the upper parts of the

  lateral edges of building elements Thus the provision

  distribution sitive moves along the bench while being

  followed by the finishing device.

  Although the dispensing device and the device

  two separate devices, it could be envisaged to combine them into a single device.

  According to another characteristic of the invention, the installation further comprises reservation and / or separation pieces, made of flexible material and suitable for being

  placed on the manufacturing area before pouring the concrete.

  Finally, in another aspect, the invention also relates to a method for manufacturing building elements

  in reinforced concrete, of the pre-slabs type, as defined above.

  This method comprises an operation consisting in simulating molding

  temporarily the lower face and the lower parts of the lateral edges of each construction element and a

  operation consisting in shaping the upper face by spinning

  re and the upper parts of the lateral edges of the ele-

construction elements.

  In the description which follows, made only by way of example

  ple, reference is made to the accompanying drawings, in which: FIG. 1 is a perspective view of an element of

  generally rectangular construction according to the

  vention; Figures 2 to 5 are perspective views of other

  construction elements of the invention, of different shapes

  annuities; Figure 6 is a partial cross-sectional view showing the side edge of a building element of the invention; there Figure 7 is a cross-sectional view showing the juxtaposition of two side edges of two construction elements; Figure 8 is a partial cross-sectional view of a building element provided with a lifting cable; Figure 9 is a partial perspective view showing

  fixing the lifting cable fitted with its external anchors

  mite on the prestressing reinforcements of the building element of Figure 8; Figure 10 is a top view of a bench suitable for being part of an installation according to the invention; Figure 11 is a sectional view along line XI-XI of Figure 10;

  FIG. 12 is a detail on an enlarged scale of the figure.

re 11;

  Figure 13 is a side view of a dispensing device

  tribution equipped with a vibrating rule according to the invention;

  Figure 14 is a view along arrow XIV of the figure

  re 13; Figure 15 is a partial view similar to that of Figure 14 in which some of the pads of the vibrating rule are raised; Figure 16 is a side view of the vibrating rule of the device of Figure 13; Figure 17 is a view similar to that of Figure 16 showing a pad of the vibrating rule in the working position; Figure 18 is a view similar to that of Figure 17 showing the same shoe in the raised position to escape an obstacle;

  Figure 19 is a partial top view of a device

  finishing tif forming part of an installation according to the invention; Figure 20 is a side view of the device of Figure 19; Figure 21 is a partial view along arrow XXI of Figure 20; Figure 22 is a schematic perspective view of part of the finishing device of Figures 19 to 21; Figure 23 is a partial perspective view of a manufacturing bench on which are placed separation and reservation pieces of different types; Figure 24 is an end view of a comb of the bench of Figure 23; Figure 25 is a partial view on an enlarged scale corresponding to Figure 24;

  Figure 26 is a sectional view along line XXVI-

XXVI of Figure 25;

  Figure 27 is a bottom view of a storage element.

flexible vation;

  Figure 28 is a sectional view along line XXVIII-

XXVIII of Figure 27;

  Figure 29 is a sectional view along line XXIX-

  XXIX of figure 27; Figure 30 is a perspective view of a reservation element provided with an extension; Figure 31 is a cross-sectional view of an intermediate rule forming part of the bench of Figure 23; Figure 32 is a cross-sectional view of a skew ruler forming part of the bench of Figure 23; FIG. 33 is a perspective view of a flexible reservation element for an electrical pad;

  Figure 34 is a bottom view of the storage element.

  vation of Figure 33; and Figure 35 is a sectional view along the line XXXV-XXXV

in Figure 34.

  First of all, reference is made to FIG. 1 which shows a construction element 10, of the pre-slab type, constituted by a concrete plate limited by a smooth lower face 12 of generally rectangular shape and by a striated upper face 14 of generally rectangular shape The faces 12 and 14 are connected to each other by two lateral banks 16 parallel to each other, each consisting of a lower part 18 which is chamfered and molded with the lower face 12 and an upper inclined part shaped by spinning The upper face 14 is consistent

  and precisely leveled by spinning before being striated.

  The concrete slab is further limited by two ends

  transverse 22 which are mutually parallel and perpendicular to

  two sides 16 The concrete plate is reinforced by a series of prestressing frames 24 which extend

  parallel to each other and parallel to the lateral banks

  the 16 of element 10 Element 10 further comprises four lifting cables 26 forming flexible loops protruding

  above the upper face 14.

  For example, the element 10 can have a width (between the edges 16) of 2.5 m and a length (between the ends 22) of up to 9 m. The nominal thickness of the element

  is normally 45 mm but can reach 120 mm.

  We now refer to FIG. 2 which shows an element 28 similar to the element 10 of FIG. 1, except that it comprises a cutout 30 of generally rectangular shape

  and a reservation 32 of generally rectangular shape.

  Reference is now made to FIG. 3 which shows another construction element 34 similar to element 10, except that it comprises an inclined edge 36 connecting one of the lateral edges and one of the ends in addition, the element 34 comprises a reservation 38 formed by the union of two different rectangular reservations, as well as a

  reservation 40 for an electrical pad.

  We now refer to Figure 4 which shows two elements

  construction elements 42 according to the invention joined together by their lateral edges These two elements have generally rounded butt ends and their lateral edges

are not exactly parallel.

  Reference is now made to FIG. 5 which shows a building element 44 similar to that of FIG. 1, except that it comprises two reinforcements 46 in sinusoids which extend near the banks 16 and which project

  vertically above the upper face 14.

  The construction elements of FIGS. 2 to 5 are also reinforced by reinforcements or prestressing cables 24 and also include four lifting cables 26 forming

  loops protruding above their upper faces.

  As shown in FIG. 6, the chamfered lower part 18 and the inclined upper part 20 of the lateral edge 16 are connected together by an intermediate part substantially perpendicular to the faces 12 and 14 In

  the example, the intermediate part 50 forms an angle of approx.

  ron 7 from the vertical Part 18 forms an angle of about 450 from the vertical, while part 20 forms an angle of about 30 from

the vertical.

  In the example, the element 10 has a nominal thickness e of 45 to 50 mm and this thickness can be increased, if

  required, up to an E value of up to 120 mm.

  For elements thicker than 50 mm, the edge is extended by a vertical part 52 beyond the part

tilted 20.

  When two elements 10 are juxtaposed by their lateral edges

  rails 16 (FIG. 7), the two upper parts 20 of the facing banks define between them a groove whose sides are rough and form between them an angle equal to 2 A This then facilitates the attachment of the concrete of the

compression table.

  The two intermediate parts 50 opposite are of great straightness and allow the two elements 10 to be

join perfectly.

  The two lower parts 18 of the banks facing each other

  put between them a space for the establishment of a

sealer 54.

  As shown in Figures 8 and 9, each of the flexible lifting cables 26 is formed from a section of cable with several strands. The section of cable is twisted so as to form an intermediate loop 56 between two branches.

  rectilinear 58 located in alignment with each other.

  The branches 58 extend transversely under the frames

  res 24 and are attached thereto by ligatures 60 (fig.

  re 9) The two ends of the cable form buttons

  62 obtained by stamping the end of the cable (see

  tails in Figure 9), making it easier to anchor the cable in

the concrete of element 10.

  As shown in Figure 8, on the prestressing cables 24 are also arranged transverse reinforcements 64 which can be flexible or rigid The upper face 14 of the element 10 (Figure 8) has ridges 66 which extend parallel to the prestressing reinforcement

  24, to facilitate the attachment of the compression slab.

  The streaks located to the right of the frames 24 are more accentuated

  killed, as shown in 68, to then allow the user to

  sator to visualize the position of the reinforcements, in the

  case a drilling of the element from above is necessary.

  We now refer to Figure 10 which shows a manufacturing bench which is similar to that described in French Patent No 85 04947 already cited, the content of which is considered

  as incorporated into this description to contribute

  to a better understanding of the invention.

  Bench 70 includes two buried solid masses 72 and 74 in concrete

  reinforced between which extends a slab 76 supporting a manufacturing area 78 This is formed by a set of very thick metal plates resting on the slab 78 by means of profiles and elastic studs.

  ques (not shown) Manufacturing area 76 defines a flat, horizontal surface of rectangular shape, the length of which can be of the order of 100 m and the width

between 2.50 m and 3 m.

  The bench 70 also includes means for tensioning and / or releasing prestressing reinforcements. In a pit 80 are arranged vertical metal profiles 82. Two tensioning cylinders 84 are articulated, of a

  part to profiles 82, and on the other hand to a trestle

tion 86.

  At the other end of the bench, an anchoring device 88 is installed vertically in a pit 90 It is thus possible to have, above the manufacturing area 78, prestressing cables 24, mutually parallel, one end of which is attached to anchor 88 and the other end

attached to the header 86.

  In accordance with the invention, the manufacturing area 78 carries two rails 92 of square section (FIG. 11) which extend

  parallel to each other and close to the two vertical edges

  blocks 94 of the manufacturing area 78 On the area 78 are also arranged two formworks of banks 96 which extend parallel to each other and whose shape allows the formwork

  side edges 16 of the elements of the invention.

* As shown in Figure 12, each formwork 96 is a profi-

  the metal having a horizontal lower face 98, a horizontal upper face 100, an external lateral side 102 vertical and an internal face 104 The latter comprises two parts: a part 106 connecting with the face 98 and inclined by about 450 relative to the 'horizontal, and a part 108 connecting with the part

  106 and with the upper face 100, this part being sensitive

  vertically vertical The parts 106 and 108 allow, during molding, to respectively form the lower part

  18 and the intermediate part 50 of a bank 16 (FIG. 6).

  The upper part 20 of the bank 16 is produced by

  forming, as will be seen later.

  As shown in Figure 11, on the concrete slab 16 are arranged, in a manner known per se, two rails 110 parallel to each other and allowing the displacement in translation of a distribution device 112, suitable for distributing and vibrating

  concrete on manufacturing area 78 (figure 13) The availability

  sitif 112 comprises a self-propelled carriage 114 movable in translation on the rails 110 and carrying a bucket 116 intended to contain concrete and the bottom of which is provided with a rotary volumetric distributor 118 driven by a motor to distribute the concrete over the entire width of the manufacturing area 78 The device 112 also carries a series of vibrating needles 122 extending across the width

  of the manufacturing area and capable of vibrating the concrete distributed

misted by the bucket 116.

  The structure of the distribution system, as it

  has just been described so far, is known per se.

  According to the invention, the dispensing device is provided

  on its posterior part in relation to its sense of transla-

  tion (arrow F) of a vibrating rule 124 arranged transversely

  above the manufacturing area and suitable for conforming

  sea by spinning the upper face 14 of the elements of cons

translation of the invention.

  The vibrating rule 124 (FIGS. 13 to 18) comprises a multi-

  plicity of vibrating pads 126 (in the example eleven in number) arranged adjacent and transversely above the manufacturing area Each pad 126 has the shape of a rectangular plate arranged vertically, this pad being

  further provided with a vibrator 128, for example of the electric type

  stick. The vibrating rule 124 comprises a frame 130 (FIG. 16) carried by the chassis 114 of the distribution device 112 by means of a lifting mechanism consisting of two hydraulic cylinders 132 of vertical axis, each interposed between the chassis 114 and the frame 130 The two jacks have a stroke which can reach approximately 700 mm. The simultaneous actuation of the two jacks 132 makes it possible to move the frame between a low working position (FIG. 16) and a high retracting position. In the low position, the frame 130 rolls on the two rails 92 of the manufacturing area 78 (FIG. 11) by means of wheels 134 In this working position, the pads 126 are able to conform the upper face of the construction elements In the high position retraction, the frame is raised at a distance from the manufacturing area, this distance corresponding to

the stroke Hl of the cylinders 132.

  The frame 130, which is produced in the form of a box,

  internally supports a cross member 136 extending horizontally-

  talally and transversely to the length of the manufacturing area This cross member 136 is guided in vertical translation by guide means 138 The cross member 138

  is connected to the upper part of the frame 130 by means of

  diary of two positioning jacks 140 with vertical actuation suitable for ensuring precise height adjustment of the cross member 136 and, consequently, of the pads 126 carried by this cross member The two jacks 140 are constituted by screw jacks provided with a counter in height and allowing precise millimeter adjustment of the position of the cross member 136 (and consequently of the pads 126), when the frame 130 is in the working position shown in FIG. 16 The jacks 140 allow adjustment in

  height H 2 (figure 16), the stroke of the jacks being for example

full of 80 mm.

  Each of the pads 126 is connected, by means of a release cylinder 142, to the common cross member 136 Each of the cylinders 142 can be controlled independently of the others to vertically move the corresponding pad 126 over a determined height H 3 During its movement in vertical translation, each shoe 126 is guided by means of

guide 144.

  When one of the jacks 142 is actuated, it operates in "YES / NO" to make the corresponding shoe 126 escape by raising it by a determined height H 3, for example 25 cm When the distribution device 112 is moved in translation in the direction of arrow F, the frame of the vibrating rule 124 is in the low position shown in FIG. 16 In this position, the jacks 140 are adjusted according to the thickness to be given to the concrete poured on the area of manufacturing Normally, the cylinders 142 are deployed, so that the pads 126 smooth the upper face 14 of a building element

(figure 17).

  If desired, one or more shoes 126 can be released vertically (Figures 15 and 18) if an obstacle is present,

  for example if a sinusoidal reinforcement 46 protrudes beyond

  above the poured slab (figure 18).

  The distribution device 112 equipped with the vibrating rule 124 makes it possible to obtain elements of the pre-slab type, the upper face of which is precisely shaped by the

pads of the vibrating rule.

  The upper parts of the lateral edges of the construction elements are then shaped by a finishing device 150 shown in FIGS. 19 to 22 which moves along the bench following the distribution device 112. The device 150 comprises a self-propelled carriage formed of a frame 152 movable in translation on the rails 92 of the manufacturing area 78 The frame 152 carries two finishing members 154 arranged symmetrically and suitable for following respectively the two formwork of the edges 96 (Figures 21 and 22) Each of the finishing members 156 comprises a ring 158 mounted around an axis XX carried by the chassis 152 and inclined by 200 relative to the vertical The respective axes XX of the two rings 158 are located in the same vertical plane transverse to the longitudinal direction of the manufacturing area and these two axes converge upwards. Each of the rings 158 is returned elastically downwards by a spring 160 coaxial with the axis XX The ring 158 is connected by a radial arm 162 to a support plate 164 itself carrying a ring 166 This assembly constitutes a movable assembly, which carries a cheek 168 on which depends an axis 170 pivotally mounted inside the ring 166.

  The moving part can be moved between a working position

  vail (Figures 19 to 22) in which the cheek 168 is in a substantially vertical position bearing on the top of the edge formwork 96 (Figures 21 and 22) and a retracting position where the cheek is raised on the au side above the bench, this lifting being authorized by the inclination of the pivot axis XX of the bushing 158 The displacement 5 of each of the moving parts is ensured by a hydraulic jack 17 whose body is connected by a spherical articulation 174 to the chassis 152 and whose rod is connected

  by a spherical joint 176 to the support plate 164.

  The cheek 168 has a lower edge 178 which is inclined towards the outside of the bench and which is capable of being supported

  longitudinally on top of the edge formwork 96 (fig.

  res 21 and 22) This inclined rim is intended to conform the inclined upper part 20 of an edge 16 of an element

  10 during construction (Figure 22).

  The cheek 168 carries an adjustable support plate 180 which, in the working position of the finishing member 154, is substantially horizontal to smooth the edge of the upper face 14 of the element 10 (FIG. 22) The plate d 'support is carried by a rod 182 movable in translation along the cheek 168, by means of two rings 184 aligned and fixed on the cheek 168 on the side directed towards the inside of the manufacturing area The plate support 180 comprises a generally flat part terminated by at least one raised edge 186, in the manner of a ski skate, as shown in FIG. 19 The support plate 180 thus makes it possible to smooth the edge of concrete elements of different thicknesses. The frame 152 of the finishing device 150 further carries a notching comb 188 suitable for producing, on the upper face 14 of a construction element 10, ridges

  such as the streaks 66 and 68 shown in Figure 8.

  The comb 188 comprises a transverse rod 190 provided with a multiplicity of teeth 192 extending in the direction of the length of the manufacturing area The comb 188 is worn

  by a rod 194 extending horizontally and transversely-

  ment to the longitudinal direction of the manufacturing area. This rod 194 pivots inside two supports 196 fixed on the chassis 152 The comb 188 can be raised in the retracting position or lowered in the working position by means of two hydraulic cylinders 198 disposed respectively on the two sides of the chassis 152 Each of the cylinders 198 is articulated, on the one hand, around an axis 200 linked to the chassis 152 and, on the other hand, around an axis 202

  connected to an arm 204 wedged on the rod 194.

  We now refer to FIG. 23 showing a part of a manufacturing area 78 similar to that of FIG. 11 On this manufacturing area are arranged different

  reservation and separation documents allowing

  be, during the same casting, construction elements

  of different shapes These reservation and separation pieces

  ration are made of a flexible material, for example

  polyurethane, elastomer or silicone.

  These parts include two combs 210 extending transversely.

  dirty across the width of the manufacturing area 78, of the reservation pieces 212 and 214, an intermediate rule 216 extending in the longitudinal direction of the area

  a bias ruler 218 and a reserve pad

vation 220.

  The comb 210 (Figures 24 to 26) is intended to form a

  separation between two adjacent building elements.

  The comb 210 has, seen from above, a generally rectangular shape. It is limited by two opposite end faces 222 whose height corresponds to that of the elements to be manufactured and whose width corresponds to the width of the manufacturing area, between the two edge formwork 96 The face 222 ends with two ends 224 similarly

  profile than that of the lateral edges of the elements to be manufactured

quer.

  In addition, each of the faces 222 is provided with vertical cutouts.

  shims 226 allowing the passage of the prestressing cables 24 (Figure 25) The two opposite faces 222 depend on a horizontal plate 228 reinforced by lateral reinforcements 230 (Figure 6) extending transversely to the longitudinal direction of the manufacturing area The comb 210 is made of a flexible self-demolding material, for example of polyurethane or an elastomer. It is thus possible to make combs of shapes specifically adapted to those of the elements to be manufactured. It will be understood that, after demolding, the ends of the elements thus produced are perfectly

  made and have no burrs.

  Reference is now made to FIGS. 27 to 29 which show a reservation part 212 which, seen from above, has a generally rectangular shape. This part is produced

  by molding a flexible material, for example polyurethane-

  made of elastomer or silicone, and comprises a plate 215 of generally rectangular shape on which two

  parallel edges 217 and two other parallel edges 219.

  These edges are provided with cutouts 221 extending vertically from the base of the part to allow the passage of prestressing cables. In addition, the part 212 comprises

  a housing 223 of generally cylindrical shape suitable for receiving

  see a magnet (not shown) Exhibit 212 can thus

  be set up on the manufacturing area by coming

  create on the prestressing reinforcement If necessary, a magnet is placed in the housing 223 to help keep the part in position, the magnet coming to the

  contact above the prestressing reinforcement.

  The part 212 is also provided with two cables 225 to facilitate its subsequent extraction, after manufacture of the prestressing elements. We now refer to Figure 30 which shows another

  reservation piece 227, also of general rectan- form

  gular, similar to room 212 This reservation room

  also includes cutouts 221 for the installation of arma-

  prestressing structures In the example, the part 226 can be provided with an extension 229, of the same shape, to allow

  the molding of thicker elements.

  The aforementioned reservation documents, which have a general form

  rectangular rail, constitute modular elements which can be juxtaposed one beside the other to form, in a building element, a reservation

appropriately shaped.

  Reference is now made to FIG. 31 which shows an intermediate rule 216 This rule consists of a profile molded from a flexible material and provided, over its entire length,

  an interlocking groove 231 opening onto the underside

  ruler 232 of the rule This rule comprises two lateral faces 234 of profile complementary to that of the edges

  side of the elements to be manufactured.

  Rule 216 is further reinforced by two long frames

  tudinal 236 extending over the entire length of the profile.

  As shown in FIG. 23, the intermediate rule 216 is intended to be placed in the longitudinal direction of the manufacturing area 78 by covering a prestressing cable 24 The intermediate rule thus makes it possible to form a longitudinal separation between two elements

  of molded construction side by side.

  Reference is now made to FIG. 32 which shows a bias rule 218 which comprises a lower rule 238 suitable for being placed on the manufacturing area by passing under the prestressing reinforcements and an upper rule 240 suitable for passing over the cables. prestressing and to be secured to the lower rule by any means

appropriate.

  The two rules 238 and 240 are both formed by

  molding from a plastic material of the polyurethane type

  ne, elastomer or silicone The lower ruler 238 is reinforced by two longitudinal reinforcements 242 and, correspondingly, the upper ruler 240 is reinforced by two longitudinal reinforcements 244 The ruler thus obtained can be placed at an angle on the manufacturing area 78 for molding building elements with an oblique edge, similar to that shown on

Figure 3.

  We now refer to Figures 33 to 35 which show

  a reservation pad 220 formed of a flexible material

  demouldable and allowing to form and make perfectly calibrated holes allowing to receive, in recovery on hardened concrete, an electrical box for interlocking

dry from the housing.

  The reservation pad 220 has a circular bottom 246 on which a generally cylindrical skirt 248 depends. In addition, the reservation pad comprises a cable 250, the two ends of which are embedded in the mass of the stud, and serving

upon extraction of the latter.

  The installation described above is used in the following way First, we have prestressing cables

  above the manufacturing area and put them under tension

  Then we have on the different manufacturing area

  rents combs, reservation pieces, intermediate rules, bias rules, studs, etc., depending on the structure

  geometric elements to be manufactured.

  Then pour the concrete using the distribution device.

  bution 212 which, thanks to its vibrating rule 124, ensures the

  conformation of the upper face of the construction elements

  The finishing device 150 then ensures the conform-

  mation of the upper part of the lateral edges of the elements

  as well as the creation of longitudinal ridges

  on the upper side of the elements.

  When the concrete is hardened, the tension of the prestressing cables is released and the cables are sheared

  in regions between two construction elements

  Adjacent tion For this, one can use a shearing device as described, for example, in the patent

French No 85 04947 already cited.

  The individual construction elements thus obtained on the manufacturing area can be removed using their lifting cables, to be stored and then shipped

on their sites of establishment.

  After manufacturing a series of construction elements, the manufacturing bench can be used directly for

  the manufacture of another series of elements.

Claims (30)

Claims   1. Prestressed concrete construction element, of the pre-slab type, comprising a thin concrete plate, provided with internal prestressing reinforcements (24), and delimited by a lower face (12), an upper face (14 ),   two lateral banks (16) generally parallel to the frames   res and two transverse ends (22), characterized in that each of the lateral edges (16) has a chamfered lower part (18) molded with the face   lower (12) and an inclined upper part (20)   formed by spinning, and in that the upper face (14)   is precisely shaped and leveled by spinning.   2 building element according to claim 1, charac-   terized in that the chamfered lower part (18) and the inclined upper part (20) of the lateral edge (16) are interconnected by an intermediate part (50) substantially perpendicular to the lower face (12) and to the upper face (14).   3. Building element according to one of claims   1 and 2, characterized in that the lower face (12) of the construction element and the lower part (18) of each lateral edge (16) of the element are smooth, while   that the upper face (14) of the element and the upper part   side (20) of the side bank are roughened by parallel streaks (66).   4 building element according to claim 1, charac-   terized in that the ridges (66) are parallel to the armatu-   preload res (21) and are more accentuated (streaks 68) to the law thereof.   5. Building element according to one of claims   1 to 4, characterized in that it comprises flexible cables   lifting (26) forming loops (56) and connected to the arma-   prestressing structures (24), the cables (26) having ends   moths in the form of buttons (62) embedded in the thickness of the element.   6. Building element according to one of claims   1 to 5, characterized in that it further comprises at least   a reservation (32,38) of the chosen form.   7. Installation for the manufacture of building elements   pre-stressed concrete, of the pre-slab type, according to one   claims 1 to 6, comprising a bench (70) comprising   an elongated manufacturing area (78), means (86,88) for tensioning prestressing reinforcements (24) above the manufacturing area and a molding apparatus   (112) movable in translation along the manufacturing area   tion (78), characterized in that the manufacturing area (78) is provided with two edge formwork (96) extending parallel to each other and along the length of the bench to mold the lower parts (18) of the side edges   (16) of the building elements (10) and in that the apparatus   molding reel comprises means (124) for shaping by spinning the upper face (14) of each element (10) and means (150) for shaping by spinning the upper parts (20) of the lateral edges (16) of each element of construction.   8 Installation according to claim 7, characterized in that the molding apparatus comprises a distribution device (112) provided with a frame (114) movable in translation along the length of the bench to distribute and vibrate concrete on the area manufacturing (78) and in that the   distribution device is provided on its posterior part   re with respect to its direction of translation (F), a vibrating rule (124) arranged transversely above the manufacturing area (78) and suitable for shaping the upper face (14) of the construction elements (10). 5 9. Installation according to claim 8, characterized in that the vibrating rule (124) comprises a multiplicity   vibrating pads (126) arranged adjacent and transverse-   above the manufacturing area (78), each shoe   (126) being provided with a vibrator (128) and connected, via the   median of a release cylinder (142), to a common crosspiece (136) carried by the chassis (114) of the distribution device, each of the release cylinders (142) being   independently controllable to move vertically-   the corresponding pad over a determined height (H 3).   10. Installation according to claim 9, characterized in that the vibrating rule (124) comprises a frame (130) carried by the chassis (114) of the distribution device (112) and in that the crosspiece (136) is connected to this frame by means of at least two positioning actuators (140) with vertical actuation, capable of ensuring precise height adjustment (H 2) of the cross member and of the pads by relative to the frame (130).   11. Installation according to claim 10, characterized in that the frame (130) of the vibrating rule (124) is connected to the frame (114) of the distribution device (112) via a lifting mechanism (132 ) suitable for moving the frame (130) between a low working position in which this frame is suitable for rolling on two rails (90) along the manufacturing area (116) and the pads (126) are suitable for conforming the upper face (14) of   construction elements (10), and a high position   drive in which the frame (130) is raised remotely   (H 1) of the manufacturing area (78).   12. Installation according to claim 7, characterized in that it comprises a finishing device (150) capable of conforming the upper parts (20) of the side edges (16), this device comprising a movable frame (152)   in translation along the length of the bench and carrying two organ-   symmetrical finishing nes (154) suitable to follow respect-   the two edge formwork (96).   13. Installation according to claim 12, characterized in that each of the finishing members (154) comprises a cheek (168) carried by a movable assembly (158,162,164) and movable between a working position where the cheek (168) is in a substantially vertical position resting on   the top of the edge formwork (96) and a retracting position   floor where it is raised laterally above the bench, and in that the cheek (168) carries an adjustable support plate (180) which, in the working position of the finishing member, is substantially horizontal to smooth a board   of the upper face (14) of the building element.   14. Installation according to claim 13, characterized in that the cheek (168) is mounted to rotate freely about a pivot axis (170) carried by the movable assembly   and which, in the working position, is substantially hori-   zontal and transverse to the length of the bench, and in that the mobile assembly comprises a ring (158) pivotally mounted about an axis (XX) inclined relative to the vertical, a radial arm (162) connected to this ring and a support plate (164) carrying the pivot axis of the cheek, a jack (172) being connected to the frame (152) of the finishing device (150) and to the support plate (164) to allow movement the cheek and the associated support plate between the working position and the retracting position. 15. Installation according to claim 14, characterized in that the pivot axis (XX) of the ring (158) is inclined by about 200 relative to the vertical, while being located in a plane transverse to the length of the bench, and in that the respective pivot axes (XX) of the   two rings (158) converge upwards.   16. Installation according to one of claims 14 and 15,   characterized in that the ring (158) of the moving element   is subjected to the action of a spring (160) tending to rappe- 1st down.   17. Installation according to one of claims 13 to 16,   characterized in that the cheek (168) has a lower edge (178) inclined towards the outside of the bench and suitable for bearing longitudinally on the top of the formwork edge (96).   18. Installation according to one of claims 13 to 17,   characterized in that the support plate (180) is carried by a rod (182) movable in translation along the cheek and has a generally planar part completed   by at least one raised edge (186).   19 Installation according to one of claims 12 to 18,   characterized in that the frame (152) of the finishing device   tion (150) further carries a comb (188) suitable for making, on the upper face (14) of a building element   (10), streaks (66) extending in the longitudinal direction nale of the bench.   20. Installation according to one of claims 7 to 19,   characterized in that it further comprises reservation and / or separation pieces (210,212,214,216,218,220) made of flexible material and suitable for being placed on   the manufacturing area (78) before pouring the concrete.   21. Installation according to claim 20, characterized in that the reservation parts comprise at least one comb (210) of flexible material comprising cutouts (226) for the passage of the prestressing reinforcements (24)   as well as side reinforcements (230).   22 Installation according to claim 20, characterized in that the reservation parts comprise at least one modular element (212, 214) of flexible material, provided with cutouts (221) for the passage of prestressing reinforcements (24) and comprising at minus a housing (223) for a magnet   permanent allowing the fixing of the element on the arma- prestressing structures.   23. Installation according to claim 20, characterized in that the reservation pieces comprise at least one intermediate rule (216) constituted by a molded profile provided with an interlocking groove (231) for receiving   a prestressing reinforcement (24).   24. Installation according to claim 20, characterized in that the reservation pieces comprise at least one bias rule (218) comprising a lower rule (238) suitable for being placed on the manufacturing area while passing   under the prestressing reinforcement (24) and a higher rule   superior (240) suitable for passing over the reinforcements of   prestressed and to be secured to the lower rule.   25. Installation according to claim 20, characterized in that the reservation parts comprise at least   a reservation pad (220) for an electrical box.   26. Method for manufacturing prestressed concrete building elements, of the pre-slab type, according to one of the   claims 1 to 6, using a bench comprising a   elongated manufacturing area, means for tensioning prestressing reinforcements above the manufacturing area and a molding apparatus movable in translation along the manufacturing area, characterized in that it includes an operation consisting in simultaneously molding the lower face and the lower parts of the lateral edges of each construction element and a   operation consisting in shaping the upper face by spinning   construction elements and to wire the upper parts of the side edges of the element of construction.   27. The method of claim 26, characterized in that the shaping operation by spinning is carried out immediately after a casting and vibration operation concrete.   28. Method according to one of claims 26 and 27, charac-   terized in that the shaping operation by spinning first comprises a shaping operation of the face   construction element and then an operation   conformation of the upper parts of the lateral banks   construction element.   29. Method according to one of claims 26 to 28, character-   laughed in that it further comprises a notching operation consisting in making longitudinal ridges on the face   of the building element.   30. Method according to claim 29, characterized in that   that this notching operation is carried out after the operation-   conformation of the upper face of the building element and before the shaping of the upper parts of the side edges of this building element. w