EP1994231A1

EP1994231A1 - Underground passageway

Info

Publication number: EP1994231A1
Application number: EP06726234A
Authority: EP
Inventors: Marcel Matiere
Original assignee: Societe Civile de Brevets Matiere
Current assignee: Societe Civile de Brevets Matiere
Priority date: 2006-03-10
Filing date: 2006-03-10
Publication date: 2008-11-26
Also published as: WO2007104839A1; AU2006340312A1

Abstract

The invention relates to an underground passageway with a plurality of passageway sections beneath a backfill of variable height. According to the invention, the passageway consists of a plurality of adjacent conduits (A, B) with parallel axes, each bounded by a wall (3) consisting of juxtaposed prefabricated elements and resting on a laying surface (15), the whole being covered by a backfill having an upper part forming a platform (2) whose level can vary with respect to the ground (14). The dimensions of the prefabricated elements each constituting adjacent conduits (A, B) are determined according to the position of the conduit along the platform, such that each conduit has a height with respect to the ground (14) which is less than that of the platform, each conduit being covered by a minimum height (e) of backfill.

Description

Underground passage

The invention belongs to the field of construction and public works. It relates to an underground structure, more particularly for the passage of vehicles below an inclined ramp.

The invention also covers prefabricated elements, especially adapted to the realization of such a work.

The railway lines are built on a platform that follows, as far as possible, the ground level and they are crossed by many crossings that must be removed, for security reasons, when the line remains active. To avoid interrupting traffic on the line for too long, underground passages are generally avoided and it is preferred to build a bridge over the tracks. This bridge must pass a relatively high height, given the size necessary for the passage of trains and supply lines. It is connected at its ends to two inclined ramps.

Often, along the road, there is a road that must be deviated to a junction or a roundabout at the base of the ramp and allowing either to pass over the railway or to return along this one.

On the other hand, in the case of a bridge crossing a river, it happens that the bridge deck is placed at a relatively high height to maintain a sufficient air clearance over the river. The bridge must then be associated with an access ramp which is often made of a real viaduct resting on distant piles. It is then possible to pass under this viaduct a road along the river and crossing the bridge at the abutments.

Even in the case of relatively large heights, it is more economical to provide such an inclined ramp to the upper part of an embankment whose height increases gradually. To avoid deviating a road along the river or a railway, it is advantageous to cross the embankment through a covered walkway.

However, the inventor has already described, for example in document EP-A-0080402, a technique for producing underground passages constituted prefabricated wall elements to make ducts of large sections and covered with a backfill.

It has become apparent that such a technique could be adapted to construct multi-track passages below a platform of variable height such as an inclined ramp.

The object of the invention is therefore to solve such problems by means of a standardized construction method which makes it possible to considerably reduce the production costs.

According to the invention, such an underground passage made below an inclined ramp, consists of several adjacent parallel-axis ducts, each limited by a wall consisting of juxtaposed prefabricated elements resting on a laying surface and comprising , in cross section, at least three elements, respectively two side members each comprising a substantially vertical side wall, a lower part bearing on the laying surface and an upper part, and at least one curved upper element resting on the elements of side and forming a vault resting on the upper parts of the two side elements and, all of the ducts being covered with a backfill having an upper part forming a platform whose level may vary with respect to the ground, the dimensions of the prefabricated elements constituting each of the adjacent ducts are determined according to the posi the duct along the platform so that each duct has, in its longitudinal median plane passing through its axis, a height with respect to the ground lower than that of the platform and that the vaults covering two adjacent ducts have a common tangent plane extending at any point to a minimum height below the platform.

In a first embodiment, the upper part of the embankment covering the ducts is inclined so as to form an access ramp to the deck of a bridge at a height determined relative to the level of the laying surface of the ducts.

In another embodiment, the structure comprises a main pipe having a height determined so as to limit a maximum clearance gauge and two lateral ducts having a lower height, and the assembly is covered with a backfill whose upper part form a platform having two access ramps inclined symmetrically on both sides of the main duct and connected to the top of the main duct.

But the invention also allows the realization of an underground structure with several passage sections, below a fill through a valley whose floor comprises a central portion placed at a lower level and two side portions whose level increases in away from the central portion, said valley being traversed by an embankment whose lower part forms a substantially flat platform.

In this case, the embankment may be traversed by a structure comprising a main pipe of maximum height for crossing the central portion of the valley and at least two lateral ducts placed respectively on either side of the main pipe and presenting each a lower height, less than the height of the platform relative to the ground at the median plane of the duct considered. Advantageously, the underpass comprises two adjacent ducts separated by a common intermediate side consisting of elements placed one after the other, each having a lower part forming a base plate on the laying surface and an upper part carrying two support members spaced apart on either side of a longitudinal median plane of the pedestal, on which rest, respectively, the upper elements of the two ducts, said support members being placed at two different levels by relative to the laying surface of the pedestal.

However, the adjacent ducts of two adjacent ducts may also be constituted, respectively, of two series of prefabricated elements placed one after the other and having two different heights. In this case, the elements of the two series are placed back to back in pairs and are interconnected by at least one cross member.

As has been indicated, the invention has the advantage of allowing the use of standardized elements for which the manufacturer normally has several molds to achieve, in particular, elements of different heights. Insofar as each duct comprises an upper element tangentially connected to a side element along a joint plane orthogonal to the connecting parts of the two elements, it is possible to use two adjacent ducts, side elements of different heights which are provided with upper connection parts having the same profile and the same orientation of joint plane, the two ducts being covered by identical upper elements made on the same mold. However, to vary the heights of two adjacent ducts, it is also possible to use side elements of the same height on which rest upper elements with different arrows.

But the invention will be better understood by the description of certain embodiments given by way of example and shown in the accompanying drawings.

Figure 1 shows, in cross section, a first application of the invention.

Figure 1a is a detail view of an intermediate support.

Figure 2 shows, in cross-section, a second application of the invention.

Figure 3 shows another embodiment of an underground passage according to the invention.

Figure 4 is a partial view of another embodiment.

Figure 5 is a detail view of the embodiment of Figure 4. Figure 6 shows another application of the invention.

FIG. 1 diagrammatically shows, in cross-section, a first application of the invention in the case of a ramp for access to a bridge 1 comprising an apron 11 resting on abutments 12. Often, to leave a tie the minimum air H between the water level 13 and the apron 11, it must be at a relatively high height h above the ground level 14.

It is therefore necessary to make, at each end of the deck 11, an access ramp 2 which is inclined to connect the ground level to that of the deck 11. It is economical to realize this ramp by means of a simple embankment placed on the ground 14 and whose height gradually increases to the level of the deck 11. As the slope of the ramp 2 must remain quite low, for example, 5%, the embankment 21 has a fairly long length. However, it often happens that a road runs along the river and must, therefore cross the embankment 21, along the abutment 12 at the bridge 1.

Often, this transverse passage consists of a bridge having an inclined span resting on two abutments and constituting the upper end of the ramp which connects to the deck 11. However, as has been indicated, the same inventor has point and developed, for several years, a technique of construction of underground passages from prefabricated elements, respectively two elements of spaced apart piers resting on the ground by an enlarged base and a curved upper element which is connected tangentially to the upper ends of the elements of piers.

The prefabrication technique makes it possible to produce molded elements of perfect quality which can therefore be calculated so as to be particularly thin and, to meet various needs, it is advantageous to have in advance several mold sets of which the dimensions vary to achieve ducts of different heights and widths. It is thus possible to produce a range of ducts whose height may vary, for example, between 1.75 and 3.5 m and which limits useful surfaces, for example, from 3.5, 5, 7.5, 10, 12.5 m ² . It is advantageous, on the other hand, for the piers elements to be curved so as to be connected tangentially to the upper element in order to produce an ovoid section which can be slightly deformed under the load of the embankment while bearing laterally on the latter. this.

On the other hand, it is also possible to produce structures with several sections of parallel passages having in cross section, for example for two adjacent sections, a central pane whose upper part forms two ball bearings on which rest the ends of two arch elements resting, on the opposite side, on curved side elements. Such an arrangement is described, for example, in EP 0 202 256 of the same inventor.

The latter therefore had the idea that it would be particularly economical to use such standardized elements simply by adapting the molds so as to vary their heights to produce adjacent ducts of variable heights making it possible to substantially follow the inclination of the ramp. For example, in the case shown in Figure 1, it will thus be possible to make four adjacent ducts A, B, C, D each allowing the passage of a traffic lane.

Each duct is then bounded by a tubular wall 3 comprising, in cross-section, an upper element 31 resting on two wall elements 32, 33. Preferably, the upper element 31 and the upper parts of the wall elements 32, 33 are curved and have the same radius of curvature so as to connect tangentially to form a continuous arch. The entire wall 3 rests on a flattened surface formed on the ground 14 and forming a horizontal platform 15. Each element of the wall 32, 33 is provided with a base 36 allowing the wall to stand straight by itself when he is lying on the ground.

As in the case of patent EP 0 202 256, the intermediate wall 33 placed between two adjacent ducts A, B may consist of a single element having two upper supports, respectively 35a, 35b, for the vault elements 31a, 31b two ducts A, B, which are formed on either side of the median plane of the wall 33.

However, as shown in Figure 1a, the upper supports 35a, 35b are formed on the intermediate platform 33, at different heights (h1, h ₂ ) relative to the laying platform 5, so that the height of the vault 31a, 31b decreases as one moves away from the abutment 12 of the bridge. It can be seen that, to produce such plates, the same molds can be used as in the technique of patent EP 0 202 256 simply by adapting the upper part so as to offset the supports 35a, 35b in height relative to one another. to the other.

Likewise, a simple adaptation of the molds makes it possible to vary the height of the vertical door of the pedestal.

For a road traffic structure, the height of the piers 33c, 34 of the duct D farthest from the abutment 12 will be determined so as to clear a template G of minimum height, the other ducts having a greater height. This minimum height may correspond to the road gauge, the highest sections A and B being used for the passage of a railway line or for a motorway. But the lower section can also be used for pedestrians or cyclists.

Several series of prefabricated elements forming the intermediate piers 33a, 33b, 33c and each having upper supports 35 formed at heights hi and h ₂ different from the base 36 will thus be realized, so that the height of the buried conduits D, C, B, A increases gradually with the height of the embankment 21 approaching the abutment 12 of the bridge 1.

Preferably, the upper supports 35a, 35b of the side members have joint planes of the same inclination, so that the upper elements 31 may be identical, even if they rest on piers of different heights.

Figure 2 shows the application of the invention to the passage of a railway for the replacement of a level crossing. In this case, it is necessary to make a backfill whose upper part forms two ramps inclined symmetrically on either side of the track E. The clearance gauge that must be left for the passage of two rail tracks is relatively important since It is necessary to take into account the height of the trains increased by that of the catenaries 16 carrying the electric lines.

It is advantageous, in this case, to make an underground passage with three adjacent ducts comprising a central duct A ₁ high enough height and two lateral ducts B ₁ , C ₂ whose height may be lower while remaining sufficient for the template crossing required for two lanes of road traffic.

As previously, the curved upper elements 31a and 31b limiting two adjacent ducts A ₁ , B ₁ , have different heights and therefore have a common tangent plane P inclined relative to the horizontal by an angle at least equal to that of the ramp 2. Preferably, each intermediate platform 33 is provided, at its upper part, two supports 35a, 35b placed at different heights and on which rest the vault elements 31a, 31b of the two adjacent ducts A ₁ , B ₁ .

The heights of the two ducts are determined so that their tangent planes are inclined with respect to the horizontal platform 15 of a sufficient angle so that, after completion of the access ramp 2, it passes a minimum height above the vault 31a, 31b of the conduit, to provide a backfill cover of thickness e sufficient to distribute the forces applied on the wall. Indeed, one of the advantages of this buried construction technique lies in the interaction between the embankment and the concrete wall which may have some flexibility, especially if it is articulated. The embankment thus makes it possible to distribute the load and to dampen the vibrations due to the circulation of the vehicles both inside the ducts and on the crossing ramp of the buried passage.

However, insofar as the embankment 21 has, at the side piers, a fairly reduced height, it may be preferable to ignore the flexibility of the wall and, on the contrary, to provide the vault elements 31 b 31c ribs 31 'which allow to apply vertical forces on the upper ends of the side piers.

On the other hand, the bases 36 of the wall elements 32, 33 are advantageously connected by concrete longitudinal joints or by a raft 37 cast in place. The entire structure thus relies on a continuous base that distributes the applied loads over a large area and thus withstands differential settlements. Such an advantage is particularly interesting for the realization of an underground passage on a relatively unstable ground, which is quite common along the river or along the tracks.

Of course, the invention is not limited to the details of the embodiments which have just been described, other variants and other applications that can be imagined without departing from the scope of protection defined by the claims.

Thus, FIG. 3 shows an exemplary embodiment of a structure with two passage sections comprising two contiguous ducts A, B each limited by a wall comprising, in cross-section, an upper element 31 resting on two pedestal elements. 32, 32 '.

In this case, the side members 32'a, 32'b placed on the adjacent sides of the two ducts A, B are advantageously connected by two cross members, upper 38 and lower 38 ', respectively. The two adjacent elements 32'a, 32'b may be slightly spaced so as to provide a space between them in which extend reinforcements left in waiting at their base and which are embedded in a sealing mortar so as to form a lower crossbar 38 '. At their upper part, the two elements can also be provided with waiting armatures which are embedded in a reinforced concrete crossmember 38 cast in place. Thus, the adjacent elements 32'a, 32'b placed back to back are secured in pairs and behave as a single element. In the case of a particularly unstable ground, the base of each duct A, B may be constituted by a raft 37a, 37b cast in place by drowning the pending reinforcements left on the inner sides of the bases 36 of the side elements in order to constituting, over the entire width of the duct, a continuous soleplate making it possible to distribute the load over a very large area and, thus, to avoid differential settlements.

Advantageously, the wall elements 32a, 32b which have different heights hi, h ₂ form, at their upper ends 35a, 35b, supports having a joint plane inclined at the same angle, for example 45 °. In this way, it is possible to use, for the two adjacent ducts A, B, upper elements 31a, 31b identical.

To achieve the side members 32, it is thus possible to use the same molds by simply moving a formwork partition to provide the upper support at a specific height.

But, to achieve ducts of different heights, it is also possible to use intermediate piers with symmetrical head, by varying the deflection of the arch element, while maintaining its range.

Such an embodiment has been shown in FIGS. 4 and 5. It can be seen that, in this case, the two adjacent ducts A, B are separated by an intermediate crossmember 33 of symmetrical shape comprising upper supports 35 arranged at the same level. On the other hand, the vault elements 31a, 31b have arrows f ₂ different so as to vary the height of the two ducts A, B.

To this end, it is possible to use molds of the same curvature simply by modifying the angle of opening of the vault. Indeed, as shown in Figure 5, the supports 35a, 35b of the two vault elements 31a, 31b advantageously form articulations that allow, if necessary, to vary the inclination of the vault at birth.

The invention therefore provides multiple possibilities and allows, from standardized elements, to adapt to the most diverse situations. Furthermore, the invention is not limited only to the case of an embankment forming an inclined ramp but can also be applied to the crossing of a valley comprising a relatively deep central portion in which passes, for example, the main bed of a river and two lateral parts that can be covered by the river in case of flood. In this case, it is generally necessary to construct a multi-pile viaduct comprising a central span above the main bed and lateral bays allowing the passage of the river in case of widening of its bed.

The invention makes it possible to very economically solve such a problem by replacing the viaduct with a backfill whose upper part forms a substantially horizontal running platform, but whose height may vary with respect to the natural terrain.

In Figure 6, there is shown, by way of example, such an application. The main bed of the river is crossed by a central duct Ai flanked by lateral ducts B ₁ , Ci which rest on a laying surface 15b, 15c placed at a higher level than in the central part, and whose elements are dimensioned. so as to give the lateral duct a lower height, the assembly being covered with a backfill 21 limited by a platform 2 which passes at a minimum height above the vaults of the ducts A ₁ , B ₁ , Ci.

Preferably, the adjacent side members are connected by a cross member 38, as described above.

It is possible to add to such a structure other lateral ducts, for example, for the passage of a road, each duct having a height determined according to the height of the embankment with respect to the ground, at its plane longitudinal median.

The reference signs inserted after the technical features mentioned in the claims, are intended only to facilitate the understanding of the latter and in no way limit the scope.

Claims

1. Underground passage with several passage sections under an embankment of variable height, with respect to the ground (14), characterized in that it consists of several adjacent conduits (A, B) with parallel axes, each limited by a wall (3) consisting of juxtaposed prefabricated elements resting on a laying surface (15) and comprising, in cross section, at least three elements, respectively two side members (32, 33) each comprising a substantially vertical side wall, a lower part (36) bearing on the laying surface (15) and an upper part (35), and at least one upper curved element (31) resting on the side elements and forming a roof resting on the upper parts ( 35) of the two side members (32, 33), and that, all the ducts being covered with a backfill having an upper part forming a platform (2) whose level can vary with respect to the ground, the dimensi prefabricated elements each constituting adjacent ducts (A, B) are determined according to the position of the duct along the platform so that each duct has, in its longitudinal median plane passing through its axis, a height relative to the ground (14) less than that of the platform and that the vaults (31a, 31b) covering two adjacent ducts (A, B) have a common tangent plane (P) extending at any point to a minimum height (e) below the platform.

2. Underpass according to claim 1, characterized in that the upper part of the embankment (21) covering the ducts is inclined to form a ramp (2) for access to the deck (11) of a bridge (1). ) at a given height (h) above the ground level (14) and traversed by at least two adjacent ducts whose heights decrease as they move away from the deck (1).

3. underground passageway according to claim 1, characterized in that it comprises a main duct (A ₁ ) having a height determined so as to limit a maximum passage gauge and at least two lateral ducts (B ₁ , C ₁ ) of lower height, respectively placed on either side of the main duct (A ₁ ), the assembly being covered with a backfill (21) whose upper part forms a platform (2) having two access ramps (2). , 2 ') inclined symmetrically on both sides of the duct main (A ₁ ) for the passage of a taxiway at a minimum height (e) above the vault (31a, 31b, 31c) of each duct (A ₁ , B ₁ , C ₁ ).

4. underground passageway according to claim 1, for the passage under an embankment through a valley whose floor comprises a central portion placed at a lower level and two side portions whose level increases away from the central portion, said valley being traversed by an embankment whose lower part forms a substantially straight platform, characterized in that it comprises a main duct (A ₁ ) of maximum height for crossing the central portion of the valley and at least two lateral ducts (B ₁ , C ₁ ), respectively placed on either side of the main duct (A ₁ ) and each having a lower height, less than the height of the platform relative to the ground at the median plane of the duct considered.

5. Underground passage according to one of the preceding claims, characterized in that two adjacent ducts are separated by a common intermediate side (33) consisting of elements placed one after the other, each having a part lower part (36) forming a baseplate on the laying surface and an upper part carrying two support members (35a, 35b) spaced apart on either side of a longitudinal median plane of the wall, on which rest, respectively, the upper elements (31a, 31b) of the two ducts (A, B).

6. underground passage according to one of claims 1 to 4, characterized in that the adjacent sides of two adjacent ducts consist respectively of two series of elements (32'a, 32'b) placed one at the following the other, the elements of the two series being placed back to back in pairs and the elements (32'a, 32'b) of each pair being interconnected by at least one cross member (38).

7. Underpass according to one of the preceding claims, characterized in that the support members (35) provided on the upper parts of the side elements (32, 33) of two adjacent ducts (A, B) have heights (hπ, h ₂ ) different.

8. Underpass according to one of the preceding claims, characterized in that the upper elements (31a, 31b) covering two adjacent ducts (A, B) have different arrows (fi, f ₂ ) so as to vary the height of the duct (A, B) to the key.

9. underground passage according to claim 7, characterized in that, each duct (A, B) comprising an upper member (31a, 31b) having two side edges each resting on a support (35) of a side member. (32, 33) along a joint plane, the side members (32a, 32b) of different heights of two adjacent ducts (A, B) are provided at their upper part with supports (35) having the same orientation of joint plane so as to allow the use of identical upper elements in the two ducts.

10. Underpass according to claim 8, characterized in that, each duct comprising a vault element (31) bearing on two side members (32, 33) of the same height, the upper elements (31a, 31b). two adjacent ducts have different arrows (fi, f ₂ ) so as to vary the height of the vault with the key and rest on the supports (35) along joint planes of different inclinations.