FR3097886A1 - Construction system in UHPC / Composite tubular element - Google Patents

Abstract

Construction system (1) comprising: - a first construction element (10); - a second construction element (30) - a tubular inner nipple (50); - an outer sleeve (70). Composite element comprising the elements of the construction system (1) Method of constructing a composite element FIGURE OF ABREGE: Fig. 1

Description

UHPC construction system / Composite tubular element

FIELD OF THE INVENTION

The present invention relates to the field of construction elements for civil engineering structures or buildings and more particularly tubular elements of the pile type in Ultra-High Performance Fiber Concrete (UHPC) or transport pipe.

BACKGROUND OF THE INVENTION

When laying the foundations for civil engineering structures, such as crossing footbridges, or buildings, it is known to beat or drill tubular construction elements such as piles or micropiles in order to be able to rely on a ground by point effect or by friction.

These piles can be made of wood, metal or reinforced concrete, and include, in the case of driven piles, a metal spike in their lower portion. In the case of driven piles, the upper portion of the pile generally includes a metal protection so that the wood or concrete does not crush under the blows of the pile driver. The pile is generally tubular and the central portion extending between the lower portion and the upper portion comprises a cylindrical housing into which concrete can be poured after driving the pile. Reinforcements can, if necessary, also be introduced into the cylindrical housing.

Generally, a composite pile is obtained by assembling a first pile on a second pile. The lower portion of the first pile is then engaged in the upper portion of the second pile which is at least partially driven into the ground and a weld bead is made to guarantee a connection and a good alignment of the piles. The implementation of such a weld bead is delicate on site and long. Finally, since the piles are generally driven in wet soils, the durability of the weld bead, and therefore the integrity of the pile, is uncertain. Indeed, a rupture of the weld bead, for example under the effect of corrosion, can lead to a relative misalignment of the first and the second pile leading to a significant reduction in the loads that can be applied to the composite pile, to a local decompression of the ground, or even a rupture of the pile.

There are also composite piles in which the connection between the piles is ensured mechanically, for example by screwing. It is then necessary to manipulate the first pile so as to make the holes coincide, which can prove to be particularly tricky when the piles have large dimensions. Finally, it is necessary to provide devices ensuring that the link is very stable over time, such devices have a relative durability or a high cost.

OBJECT OF THE INVENTION

The object of the invention is to improve the reliability of a concrete pile and/or to facilitate its implementation.

To this end, provision is made, according to the invention, for a constructive system comprising a first tubular construction element with a first longitudinal axis comprising a first wall made of a first material comprising cement and delimited by a first outer surface and a first inner surface. The first wall comprises at least a first longitudinal reinforcement, a first portion of the first longitudinal reinforcement projecting from a first end of the first construction element over a first waiting distance. The construction system also comprises a second tubular construction element with a second longitudinal axis comprising a second wall made of a second material comprising cement and which is delimited by a second outer surface and a second inner surface. The second wall comprises at least a second longitudinal reinforcement, a second portion of the second longitudinal reinforcement projecting from a second end of the second construction element over a second waiting distance. The constructive system comprises a tubular inner nipple shaped to come into engagement with the first element on the one hand and the second element on the other hand and an outer sleeve shaped to come into engagement with the first element on the one hand and on the other leaves the second element.

A constructive system is thus obtained, made up of lightweight elements that are easy to handle, the devices of which make it possible to create a junction by implementing a simple and reliable sealing technology. Finally, the tubular geometry of the pile makes it light, easy to handle and allows concrete to be poured inside.

A particularly light and strong pile is obtained when the first material comprising cement and/or the second material comprising cement is Ultra High Performance Fiber Concrete.

Advantageously, the first waiting distance and the second waiting distance are substantially equal.

The operations of casting or transporting products in the elements are facilitated when the first inner surface and the second inner surface are of identical section and/or when the first outer surface and the second outer surface are of identical section.

Advantageously, the first inner surface and/or the second inner surface and/or the first outer surface and/or the second outer surface has a circular section.

It is possible to inject the soils when the first construction element comprises at least one first channel extending in the first wall and which connects the first outer surface and the first inner surface and/or when the second construction element comprises at at least a second channel extending in the second wall and which connects the second interior surface and the second exterior surface.

An economical embodiment is obtained when the tubular inner nipple and/or the outer sleeve are made of metal.

The implementation times - in particular the phases of fixing the piles together - are reduced when the tubular inner nipple and/or the outer sleeve comprises at least one hole.

Advantageously, the tubular inner nipple and/or the outer sleeve is in the shape of a straight cylinder.

It is possible to easily check the conformity of the seals when the inner tubular and/or outer nipple includes at least one removable part.

The positioning of the sleeves is faster when the inner tubular nipple and/or the outer sleeve comprises a longitudinal positioning stop and/or when the outer sleeve comprises a connection to the inner tubular nipple.

Pile driving can easily be carried out when the outer sleeve is sealed to the first end of the first building element and the second end of the second element includes an additional sleeve sealed to the second end of the second element.

The invention also applies to a method for constructing a composite tubular device using a construction system comprising a first tubular construction element with a longitudinal axis comprising a first wall made of a first material comprising cement delimited by a first exterior surface and a first interior surface, the first wall comprising at least a first longitudinal reinforcement, a first portion of the first longitudinal reinforcement projecting from a first end of the first construction element over a first waiting distance . The construction system comprises a second tubular construction element with a longitudinal axis comprising a second wall made of a second material comprising cement delimited by a second outer surface and a second inner surface, the second wall comprising at least a second longitudinal reinforcement, a second portion of the second longitudinal reinforcement projecting from a first end of the second construction element over a second waiting distance. The constructive system comprises a tubular inner nipple shaped to come into engagement with the first element on the one hand and the second element on the other hand and an outer sleeve shaped to come into engagement with the first element on the one hand and on the other leaves the second element. The process includes the following steps:

a) arranging the first construction element so that the first longitudinal axis extends in a main direction;

b) engage the inner tubular nipple on the first end of the first element and secure it in position;

c) engage the first outer sleeve portion on the first end of the first element and immobilize it in position;

d) filling a junction volume delimited by the inner tubular nipple, the outer sleeve and the first end of the first element using a third material comprising cement;

e) positioning the second end of the second construction element so as to engage the second portion of the second longitudinal reinforcement in the junction volume until a first distal part of the first longitudinal reinforcement comes into abutment against the second end of the second construction element and/or that a second distal part of the second longitudinal reinforcement comes into abutment against the first end of the first construction element, the tubular inner nipple and the outer sleeve coming into engagement with the second end of the second construction element construction.

This results in a rapid joining process for two construction elements, without adding heat and requiring no power supply. The joining technology is reliable and the process eliminates seal drying times.

The junction of the two construction elements is particularly strong when the third material containing cement is Ultra High Performance Fiber Concrete.

It is easy to implement the process in all orientations of the elements when step d) of filling the junction volume is carried out by injection.

The method is easy and quick to implement when the step of immobilizing the outer sleeve and/or the inner tubular nipple in position is carried out by nailing into the first construction element and/or the second construction element.

It is possible to inject the soils when the process includes the additional steps of:

f) arranging a first shutter and a second shutter in an interior volume delimited by at least the first wall and/or the second wall;

g) introducing a cement slurry into an injection volume delimited by at least the first wall surface and/or the second wall and the first obturator and second obturator.

The invention also relates to a composite tubular element comprising at least a first tubular construction element, a second tubular construction element, a tubular inner nipple and an outer sleeve as defined previously.

Other characteristics and advantages of the invention will become apparent on reading the following description of a particular embodiment of the invention.

Reference will be made to the appended figures, including:

is a schematic perspective view of an exploded view of a composite pile according to the invention;

is a schematic view in longitudinal section of a first pile according to a first embodiment of the invention;

is a schematic view in longitudinal section of a second pile according to a first embodiment of the invention;

is a partially cut-away schematic perspective view of a set of sleeves according to the invention;

is a schematic exploded view in longitudinal section of the sleeve assembly of Figure 4;

is a schematic view in longitudinal section of a first step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a second step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a third step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a fourth step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a fifth step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a sixth step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a seventh step of a first embodiment of a method of construction according to the invention;

is a diagrammatic view in longitudinal section of an eighth step of a first embodiment of a method of construction according to the invention;

is a diagrammatic view in longitudinal section of a ninth step of a first embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a second embodiment of a sleeve according to the invention;

is a schematic view in longitudinal section of an injection step according to a second embodiment of a construction method according to the invention;

is a schematic view in longitudinal section of a first step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a second step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a third step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a fourth step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a fifth step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a sixth step of a third embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a first pile according to a second embodiment of the invention;

is a schematic view in longitudinal section of a second pile according to a second embodiment of the invention;

is a schematic view in longitudinal section of a first step of a fourth embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a second step of a fourth embodiment of a method of construction according to the invention;

is a schematic view in longitudinal section of a third step of a fourth embodiment of a method of construction according to the invention.

Other characteristics and advantages of the invention will appear on reading the following description of particular non-limiting embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring to Figures 1 to 5, the construction system 1 according to the invention comprises a first tubular construction element - here a first pile 10, a second tubular construction element - here a second pile 30, a tubular inner nipple 50 and a outer sleeve 70.

The first pile 10 is substantially tubular with a longitudinal axis Oy. The first pile 10 comprises a first wall 11 of Ultra-High Performance Fiber Concrete (UHPC) delimited by a first outer surface 12 and a first inner surface 13. The first surface exterior 12 is a straight cylinder with a first longitudinal axis Oy and a first exterior diameter D ₁₂ , thus the first exterior surface has a circular section _. The first inner surface 13 is a straight cylinder with a first longitudinal axis Oy and a first inner diameter D ₁₃ , thus the first inner surface has a circular section. The first wall 11 comprises six first reinforcing bars 14.1 to 14.6 longitudinal. A first upper portion 15.1 to 15.6 respectively of the first reinforcing bars 14.1 to 14.6 projects from a first upper end 16 of the first pile 10 over a first waiting distance L ₁₀ , here equal to two hundred millimetres. A first lower portion 17.1 to 17.6 respectively of the first rebars 14.1 to 14.6 projects from a first lower end 18 of the first pile 10 over a first waiting distance L ₁₀ , here equal to two hundred millimeters.

Advantageously, the first pile 10 comprises a first series 19 of four first channels 19.1 to 19.4 which extend in the first wall 11 and which connect the first exterior surface 12 and the first interior surface 13. The first series 19 of four first channels 19.1 to 19.4 is located close to the first upper end 16 of the first pile 10. A second series 20 of first four channels 20.1 to 20.4, a third series 21 of first four channels 21.1 to 21.4 and a fourth series 22 of first four channels 22.1 to 22.4 similar to the first series 19 are regularly located on the first wall 11 between the first upper end 16 and the first lower end 18. The channels 19.1-19.4, 20.1-20.4, 21.1-21.4 and 22.1-22.4 can be made during molding of the first pile 10 or drilled after manufacture of the first pile 10.

The second pile 30 is identical to the first pile 10 and is of substantially tubular shape with a first longitudinal axis Oy ₁₀ . The second pile 30 comprises a second wall 31 of Ultra-High Performance Fiber Concrete (UHPC) delimited by a second outer surface 32 and a second inner surface 33. The second outer surface 32 is a straight cylinder with a second longitudinal axis Oy ₃₀ and of second outer diameter D _32, here equal to the first outer diameter D ₁₂ , thus the second outer surface has a circular section _. The second inner surface 33 is a straight cylinder with a second longitudinal axis Oy ₃₀ and a second inner diameter D ₃₃ , here equal to the first inner diameter D ₁₃ , thus the second inner surface has a circular section. The second wall 31 comprises six second reinforcing bars 34.1 to 34.6 longitudinal. A second upper portion 35.1 to 35.6 respectively of the second rebars 34.1 to 34.6 projects from a second upper end 36 of the second pile 30 over a second waiting distance L ₃₀ , here equal to two hundred millimeters. A second lower portion 37.1 to 37.6 respectively of the second rebars 34.1 to 34.6 projects from a second lower end 38 of the second pile 30 over a second waiting distance L ₃₀ , here equal to two hundred millimeters. The second pile 30 comprises a first series 39 of four channels 39.1 to 39.4 which extend in the first wall 11 and which connect the second exterior surface 32 and the second interior surface 33. The first series 39 of four second channels 39.1 to 19.4 is located close to the second upper end 36 of the second pile 30. A second series 40 of four second channels 40.1 to 40.4, a third series 41 of four second channels 41.1 to 41.4 and a fourth series 42 of four second channels 42.1 to 42.4 similar to the first series 39 of seconds are regularly located on the second wall 31 between the second upper end 36 and the second lower end 38. The channels 39.1-39.4, 40.1-40.4, 41.1-41.4 and 42.1-42.4 can be made molding of the second pile 30 or drilled after manufacture of the second pile 30.

The inner tubular nipple 50 is, here, a straight steel cylinder with a longitudinal axis Oy ₆₂ of length L ₅₀ , here equal to three hundred millimeters. The inner tubular nipple 50 comprises an outer surface 51 of inner tubular nipple 50 of third outer diameter D ₅₁ and an inner surface 52 of inner tubular nipple 50 of third inner diameter D ₅₂ . The third outside diameter D ₅₁ is here substantially equal to the first inside diameter D ₁₃ . The tubular inner nipple 50 has a first inner end portion 53 and a second inner end portion 54.

The outer sleeve 70 is, here, a straight steel cylinder with a longitudinal axis Oy ₆₂ which comprises an outer surface 71 of outer sleeve 70 of fourth outer diameter D ₇₁ and inner surface 72 of outer sleeve 70 of fourth outer diameter D ₇₂ . The fourth outer diameter D ₇₂ is here substantially equal to the first outer diameter D ₁₂ . The outer sleeve 70 has a first outer end portion 73 and a second outer end portion 74.

The tubular inner nipple 50 and the outer sleeve 70 are, here, connected to each other using a welded plate 60 whose lower edge 61 is placed at a distance d ₆₁ - here equal to fifty millimeters– from the distal end 57 of the second inner end portion 54 and from the distal end 77 of the second outer end portion 74. The tubular inner nipple 50 and the outer sleeve 70 thus connected constitute a set of binding 62.

The implementation of the invention will be described in application to the installation by drilling of a composite pile 100 using the construction system 1.

With reference to Figures 6 to 14, and according to a first step, the first pile 10 is placed in a vertical drilling 80 of the ground 81 so that the first longitudinal axis Oy extends in a substantially vertical direction. To do this, the first pile 10 is craned directly above the borehole 80 and its first lower end is introduced into the borehole 80. The descent of the first pile 10 into the borehole 80 is stopped so that the first upper end 16 of the first pile 10 project from the ground 81.

According to a second step, the connection assembly 62 is engaged on the first upper end 16 of the first pile 10 by aligning its longitudinal axis Oy ₆₂ with the longitudinal axis Oy of the first pile 10 then by performing a translation along the longitudinal axis Oy until the edge 61 of the plate 60 comes into contact with the first upper end 16 of the first pile 10.

According to a third step, an operator then secures the connection assembly 62 by nailing the outer sleeve 70 to the first pile 10 with nails 63.1 to 63.4. Optionally, the operator can also nail the inner tubular nipple 50 to the first pile 10. Thus, the inner tubular nipple 50 and the outer sleeve 70 are immobilized in position relative to the first pile 10.

In this position shown in Figure 7, the first upper portions 15.1 to 15.6 of the first reinforcing bars 14.1 to 14.6 extend in a junction volume 64 delimited by the outer surface 51 of the inner tubular nipple 50, the inner surface 72 of the outer sleeve 70 and the first upper end 16 of the first pile 10.

As seen in Figure 7, the outer surface 51 of the second inner end portion 54 of the tubular inner nipple 50 is tangent to the first inner surface 13 of the first pile 10 and the second inner end portion 54 of the inner nipple tubular 50 covers the second inner surface 33 over a distance d _recintsup of about fifty millimeters. Similarly, the inner surface 72 of the second outer end portion 74 of the outer sleeve 70 is tangent to the second outer surface 32 of the second pile 30 and the second outer end portion 74 of the outer sleeve 70 covers the second outer surface 32 over a distance d _recextsup of about fifty millimeters.

According to a fourth step, the junction volume 64 is filled using UHPFRC 67.

According to a fifth step, the second pile 30 is craned in order to position the second end 38 of the second pile 30 so as to engage the second lower portions 37.1 to 37.6 of the second reinforcing bars 34.1 to 34.6 in the junction volume 64. The second end 38 of the second pile 30 is then brought closer to the first end 16 of the first pile 10 until at least a first distal part 23.1 to 23.6 of one of the first upper portions 15.1 to 15.6 of one of the first concretes 14.1 to 14.6 abuts against the second lower end 38 of the second pile 30 and/or a second distal part 43.1 to 43.6 of one of the second lower portions 37.1 to 37.6 of one of the second concrete bars 34.1 to 34.6 abuts against the first end 16 of the first pile 10.

In this position shown in Figure 8, the outer surface 51 of the first inner end portion 53 of the tubular inner nipple 50 is tangent to the second inner surface 33 of the second pile 30 and the first inner end portion 53 of the tubular inner nipple 50 covers the second inner surface 33 over a distance d _recintsup of about fifty millimeters. Similarly, the inner surface 72 of the first outer end portion 73 of the outer sleeve 70 is tangent to the second outer surface 32 of the second pile 30 and the first outer end portion 73 of the outer sleeve 70 covers the second outer surface 32 over a distance d _recextinf of about fifty millimeters.

Optionally, and according to a sixth step, an operator secures the connection assembly 62 by nailing the outer sleeve 70 to the second pile 30 with nails 66.1 to 66.4.

The laying of the composite pile 100 continues until the second upper end 36 of the second pile 30 is at the height of the finished ground (FIG. 9). For implementation in deeper boreholes, additional piles can be connected to the second upper end 36 of the second pile 30.

The interior of the composite pile 100 – delimited in particular by the first wall 11 and the second wall 31 – can then be poured using an injection hose 90 fitted with a lower shutter 91 and an upper shutter 92 according to a technique known to those skilled in the art under the name of soil fracturing–or pile breakdown–and which is shown by way of indication in FIGS. 10 to 12. The pressurized concrete penetrates the ground 81 through the holes radials of the section of the composite pile 100 located between the lower shutter 91 and the upper shutter 92 (here, the holes of the first series 19, of the second series 20 of the third series 21 and of the fourth series 22). The volume of concrete which extends in the central housing of the composite pile 100 can advantageously be reinforced by the introduction of one or more reinforcing bars or strands, which further improves the resistance of the composite pile to traction according to the longitudinal axis Oy.

A composite pile 100 composed of easily transportable elements is thus obtained. The relative positioning of the first pile 10 and the second pile 30 is rapid thanks to the guiding of the inner tubular nipple 50 and the outer sleeve 7. The junction of the first pile 10 and the second pile 30 is made by sealing using UHPFRC which is a reliable technique. The inner tubular nipple 50 and the outer sleeve 70 form a permanent formwork for the sealing of the first pile 10 on the second pile 30 and also make it possible to lock the relative position of the two piles while waiting for the drying of the sealing of the reinforcements, which accelerates the laying process.

Finally, the sealed junction between the first pile 10 and the second pile 30 is independent of the resistance over time of the inner tubular nipple 50 or the outer sleeve 70.

The construction system 1 is also suitable for producing a horizontal composite tubular element 100 according to a second embodiment of the method of the invention.

The first, second and third steps of the method described above are identical and applied to a presentation of the first pile 10 and of the sleeve so that the first longitudinal axis Oy ₁₀ and the longitudinal axis Oy62 are horizontal. The fourth step of filling the junction volume 64 is shifted to the end, at the end of the fifth and sixth steps and is carried out by injection.

Figures 15 and 16 detail this injection step. The outer sleeve 70 is provided with an upper half-shell 78 attached by bolting to a lower half-shell 79. The lower half-shell 79 is provided with an injection orifice 65 and the upper half-shell 78 is provided a vent orifice 66. During the final injection step, the UHPC 67 is injected under pressure through the injection orifice 65 until it overflows through the vent orifice 66. After drying, it is possible to visually check the good quality of the injection connection by removing the upper half-shell 78.

Elements identical or similar to those described will bear a numerical reference increased by one hundred in the following description of the third embodiment of the method of the invention described in relation to a use of the constructive system 1 for the repair of a pipe. 93 existing extending along a horizontal longitudinal axis Oy93.

According to a first step, a defective portion 94, here two meters long, is cut out and deposited (figure 17). The pipe 93 then comprises a first section 93.1 and a second section 93.2 respectively delimited by a first facies 95.1 of cross section and a second facies 95.2 of cross section.

According to a second step shown in Figure 18, the wall 96.1 of the first facies 95.1 is cored to solidarize therein by chemical sealing six third reinforcing bars 93.11 to 93.16 respectively having an end portion 93.110 to 93.160 projecting from the first facies 95.1 d a third waiting distance L _93.1 of two hundred millimetres. In a homologous manner, the wall 96.2 of the second facies 95.2 is cored to secure therein by chemical sealing six fourth concrete bars 93.21 to 93.26 respectively having an end portion 93.110 to 93.160 projecting from the second facies 95.2 by a fourth distance d waiting L _93.2 of two hundred millimetres.

According to a third step shown in Figure 19, a first tubular element 10 with a total length substantially less than two meters is provided with a first tubular inner nipple 50 and a first outer sleeve 70 independent as well as a second nipple tubular interior 150 and a second outer sleeve 170 independent. As seen in Figure 19, the first tubular inner nipple 50, the second tubular inner nipple 150, the first outer sleeve 70 and the second outer sleeve 170 occupy a standby position shown in Figure 17 in which the first inner end portion 53 and the first outer end portion 73 are substantially recessed from the first upper portions 15.1 to 15.6 of the first reinforcing bars 14.1 to 14.6. The second inner end portion 153 and the second outer end portion 173 are substantially recessed from the first lower portions 17.1 to 17.6 of the first reinforcing bars 14.1 to 14.6.

According to a fourth step represented in FIG. 20, the first tubular element 10 is placed between the first facies 95.1 and the second facies 95.2 of the pipe 93, after retraction of the first outer tubular sleeve 70, of the second outer sleeve 170, of the first inner nipple tubular 50 and the second tubular inner nipple 150 on the first tubular element 10. According to a fifth step represented in FIG. 21, the first tubular inner nipple 50 and the second tubular inner nipple 150 are translated along the first longitudinal axis Oy ₁₀ so as to extend between the first section 93.1 and the second section 93.2 of the pipe 93. Such a translation can be done manually or mechanically through the inside of the pipe 93 according to the internal diameter of the pipe 93. Optionally, the first tubular inner nipple 50 and the second tubular inner nipple 150 are nailed to the first tubular element 10 and/or respectively to the first section 93.1 or second section 93.2. In a homologous manner, the first outer sleeve 70 and the second outer sleeve 170 are translated along the first longitudinal axis Oy10 of the first tubular element 10 so as to extend between the first section 93.1 and the second section 93.2 of the pipe 93. Optionally , the first outer sleeve 70 and the second outer sleeve 170 are nailed to the first tubular element 10 and/or respectively to the first section 93.1 or second section 93.2.

According to a fifth step represented in FIG. 22, UHPFRC 67 is injected into the junction volume 64 through the injection orifice 65 until it overflows through the vent orifice 66. In a homologous manner, UHPFRC 167 is injected in the junction volume 164 through an injection orifice 165 until it overflows through a vent orifice 166.

Although here the implementation of the constructive system has been described in connection with the laying of bored piles, the invention also applies to the laying of driven piles. For such an application, the outer sleeve 70 is sealed to the first end of the first pile 10, for example by fitting the inner surface 72 of the outer sleeve 70 with annular protuberances 75 and by installing the outer sleeve 70 in the mold of the first element 10 (figure 23). An additional sleeve 23 is for its part sealed on the second end 36 of the second element 30 (FIG. 24).

The first pile 10 is driven after the first lower end 18 has been fitted with a driving tip 24 and the first upper end 16 has been fitted with a suitable driving head 25.

When the first pile 10 is sufficiently sunk into the ground at the end of the first piling operations (figure 25), the piling head 25 is deposited. The inner tubular nipple 50 is then attached to the first pile 10 (FIG. 26). Junction volume 64 is then filled using UHPFRC 67.

At the end of this filling, the second pile 30 is craned in order to position the second end 38 of the second pile 30 so as to engage the second lower portions 37.1 to 37.6 of the second reinforcing bars 34.1 to 34.6 in the junction volume 64 The second end 38 of the second pile 30 is then brought closer to the first end 16 of the first pile 10 until at least a first distal part 23.1 to 23.6 of one of the first upper portions 15.1 to 15.6 of one of the first reinforcing bars 14.1 to 14.6 come into abutment against the second lower end 38 of the second pile 30 and/or that a second distal part 43.1 to 43.6 of one of the second lower portions 37.1 to 37.6 of one of the second reinforcing bars 34.1 to 34.6 come into abutment against the first end 16 of the first pile 10. Then, the outer sleeve 70 is welded to the additional sleeve 23. This connection makes it possible to continue the driving operations without waiting for the final setting of the UHPFRC 67 (figure 27 ). The driving head 25 can then be placed on the second upper end 36 of the second pile and the driving operations can continue.

Of course, the invention is not limited to the embodiments described but encompasses any variant falling within the scope of the invention as defined by the claims. Especially,

• although the invention is described here in connection with the manufacture of a pile and a transport conduit, the invention also applies to other types of tubular construction elements such as, for example, tunnels, sewage pipes, or waterworks or penstocks;
• although here the first interior surface, the second interior surface, the first exterior surface and the second exterior surface are identical right cylinders, the invention also applies to other types of geometry for the interior and exterior surfaces such as example of square, oval, rectangular, triangular or any sections, or first interior or exterior surfaces of different sections;
• although here the first tubular element is made of UHPFRC, the invention also applies to other types of first material comprising cement such as, for example, standard concrete or mortar;
• although here the first tubular element is made of UHPFRC, the invention also applies to other types of second material comprising cement such as, for example, standard concrete or mortar;
• although here the junction of the first and second piles is carried out using UHPFRC, the invention also applies to other types of third material comprising cement such as for example standard concrete or mortar;
• although here the pile comprises four series of four radial connection channels connecting the interior surface and the exterior surface of the pile, the invention also applies to a different number of series and channels, such as for example between one and five or more than six channels. These channels can also extend in directions that are not radial, as long as the distal end of these channels opens onto an outer surface of the pile;
• although here the composite element comprises a first and a second tubular construction element, the invention also applies to a composite element comprising more than two construction element;
• although here the construction elements comprise six longitudinal reinforcing bars, the invention also applies to a different number of longitudinal reinforcements such as for example a single reinforcement, between two and five or more than six. In the same way, the longitudinal reinforcements can be of another type such as for example cables or tie rods, prestressed or not, or synthetic reinforcements, the radial position of the longitudinal reinforcements can have non-identical spacings. ;
• although here the reinforcements project from both ends of the construction elements, the invention also applies to construction elements provided with reinforcements at only one of their ends;
• although here the armatures project over a distance of two hundred millimeters, the invention also applies to expectations of a different length;
• although here the ends of the frames are straight, the invention also applies to other types of ends of frames such as ends provided with butts or nuts;
• although here the outer and inner sleeves include fixing holes, the invention also applies to non-drilled sleeves which can be drilled on site or at the time of their fixing as well as to other types of modes of fastening such as strapping or gluing;
• although here the sleeves are made of steel, the invention also applies to sleeves made of other materials such as for example sleeves made of synthetic material, mineral or ferrous metal or not;
• although here the tubular inner nipple and the outer sleeve are linked by a flat having a lower edge, the invention also applies to other modes of connection such as for example a cable, a screwed connection. Similarly, the invention also applies to other types of longitudinal positioning stops than the flat, such as for example a stud placed on one and/or the other of the sleeves. Finally, the invention also applies to an outer sleeve and an inner tubular nipple that are independent and/or devoid of stops;
• although here the connection assembly comprises a removable outer sleeve part in the form of a bolted half-shell, the invention also applies to other types of removable sleeve part such as for example a sleeve sector lower or higher than one hundred and eighty degrees, a removable part mounted on a hinge or slide;
• although here the outer and inner sleeve comes to overlap on the first element and the second element, the invention applies to other types of conformation making it possible to engage the sleeve with the first and the second element such as for example a sleeve provided with an inner surface arranged to come at least partially tangent to the first and/or the second inner surface of the piles and/or a sleeve provided with an outer surface arranged to come at least partially tangent to the first and/or the second outer surface of the piles;
• although here the first outer sleeve and the first tubular inner nipple are mounted on the first pile during its implementation on site, the invention also applies to a first pile, the first end of which is equipped, during its manufacture, of the first outer sleeve and/or of the first tubular inner nipple.

Claims (20)

Construction system (1) comprising:
a first tubular construction element (10) with a first longitudinal axis (Oy ₁₀ ) comprising a first wall (11) made of a first material comprising cement, the first wall (11) being delimited by a first outer surface (12) and a first inner surface (13) and comprising at least a first longitudinal reinforcement (14.1-14.6), a first portion (15.1-15.6) of the first longitudinal reinforcement (14.1-14.6) projecting from a first end (16) of the first building element (10) over a first waiting distance (L ₁₀ );
a second tubular construction element (30) with a second longitudinal axis (Oy ₃₀ ) comprising a second wall (31) being delimited by a second outer surface (32) and a second inner surface (33) and made of a second material comprising cement , the second wall (31) comprising at least a second longitudinal reinforcement (34.1-34.6), a second portion (35.1-35.6) of the second longitudinal reinforcement (34.1-34.6) projecting from a second end (36) of the second building element (30) over a second waiting distance (L30);
a tubular inner nipple (50) shaped to come into engagement with on the one hand the first end (16) of the first element (10) and on the other hand the second end (36) of the second element (30);
an outer sleeve (70) shaped to come into engagement with firstly the first end (16) of the first element (10) and secondly the second end (36) of the second element (30). Construction system (1) according to claim 1, in which the first material comprising cement and/or the second material comprising cement is Ultra High Performance Fiber Concrete. Constructive system (1) according to any one of the preceding claims, in which the first waiting distance (L ₁₀ ) and the second waiting distance (L ₃₀ ) are substantially equal. Construction system (1) according to any one of the preceding claims, in which the first internal surface (13) and the second internal surface (33) are of identical section. Building system (1) according to any one of the preceding claims, in which the first outer surface (12) and the second outer surface (32) are of identical section. Building system (1) according to any one of the preceding claims, in which the first inner surface (13) and/or the second inner surface (33) and/or the first outer surface (12) and/or the second outer surface (32) has a circular section. Building system (1) according to any one of the preceding claims, in which the first building element (10) comprises at least one first channel (19.1-19.4; 20.1-20.4; 21.1-21.4; 22.1-22.4) extending in the first wall (11) and which connects the first exterior surface (12) and the first interior surface (13). Construction system (1) according to any one of the preceding claims, in which the second construction element (30) comprises at least one second channel (39.1-39.4; 40.1-40.4; 41.1-41.4; 42.1-42.4) extending in the second wall (31) and which connects the second exterior surface (32) and the second interior surface (33). Construction system (1) according to any one of the preceding claims, in which the tubular inner nipple (50) and/or the outer sleeve (70) is in the form of a straight cylinder. Construction system according to any one of the preceding claims, in which the tubular inner nipple (50) and/or the outer sleeve (70) comprises at least one removable part (78). Construction system (1) according to any one of the preceding claims, in which the tubular inner nipple (50) and/or the outer sleeve (70) comprises a longitudinal positioning stop (61). Construction system (1) according to any one of the preceding claims, in which the tubular inner nipple (50) and/or the outer sleeve (70) are made of metal. Building system according to claim 12, wherein the outer sleeve (70) is sealed to the first end of the first building element (10) and the second end (36) of the second element (30) comprises an additional sleeve (23) sealed at the second end (36) of the second element (30). Method of constructing a composite tubular device using a construction system (1) according to any one of the preceding claims, comprising the following steps:

1. arranging the first building element (10) so that the first longitudinal axis (Oy10) extends in a main direction;
2. engaging the inner tubular nipple (50) on the first end (16) of the first building element (10) and securing it in position;
3. engaging the outer sleeve (70) on the second end (36) of the second building element (30) and securing it in position;
4. filling a junction volume (64) delimited by the inner tubular nipple (50), the outer sleeve (70) and the first end (16) of the first construction element (10) using a third material comprising cement (67);
5. positioning the second end (36) of the second construction element (30) so as to engage the second portion (37.1-37.6) of the second longitudinal reinforcement (34.1-34.6) in the junction volume (64) until a first distal part (23.1-23.6) of the first longitudinal reinforcement (14.1-14.6) comes into abutment against the second end (38) of the second construction element (30) and/or a second distal part (43.1-43.6 ) of the second longitudinal reinforcement (34.1-34.6) comes into abutment against the first end (16) of the first construction element (10), the tubular inner nipple and the outer sleeve coming into engagement with the second end (36) of the second building element (30).

A method according to claim 14, wherein the third material comprising cement (67) is Ultra High Performance Fiber Concrete. Method according to one of Claims 14 or 15, in which step d) of filling the junction volume (64; 164) is carried out by injection. Method according to one of Claims 14 to 16, in which the step of immobilizing the outer sleeve (70) and/or the inner tubular nipple (50) in position is carried out by nailing into the first construction element (10) . Method according to one of Claims 14 to 17, comprising an additional step of securing the outer sleeve (70) and/or the tubular inner nipple (50) to the second construction element (30). A method according to any of claims 14 to 18 comprising the additional steps of:
f) arranging a first shutter (91) and a second shutter (92) in an interior volume delimited by at least the first wall (11) and/or the second wall (31);
g) introducing a cement slurry into an injection volume delimited by at least the first wall (11) and/or the second wall (31) and the first shutter (91) and second shutter (92). Composite tubular element (100) comprising at least a first construction element (10), a second construction element (30), a tubular inner nipple (50) and an outer sleeve (70) of a construction system (1) according to any of claims 1 to 13.