Concrete bridge without heavy maintenance

Abstract

A bridge (2) comprising a support slab (20) having an upper face arranged to support a traffic lane (1) and a lower face opposite the upper face, said bridge (2) further comprising at least one support member (22) of said bridge (2) and a plurality of anchor rods (21) secured on the one hand to the lower face of the support slab (20) so as to improve the mechanical strength thereof, and on the other hand to said support member (22), said support slab (20) being at least partially made of concrete and the plurality of anchor rods (21) being at least partially made of steel, said support slab (20) at least partially covering said anchor rods (21) and said support member (22) at least partially covering said anchor rods (21). Abstract figure: Figure 1

Description

Title of the invention: Concrete bridge without heavy maintenance Technical field

[0001] The present invention relates to the field of bridges, particularly railway bridges.

[0002] A railway track comprises, in a known manner, two parallel longitudinal rails fixed to a plurality of sleepers arranged perpendicular to the rails. The sleepers themselves rest on a rigid support or on ballast supporting the railway track.

[0003] In order to ensure the continuity of the railway track over obstacles, such as, for example, gaps, roads, railways or waterways, it is known to provide, at these locations, railway bridges to support the track. Such bridges can be made of metal and / or concrete.

[0004] A railway bridge most often comprises, in a known manner, a concrete support slab configured to support a portion of railway track. The support slab is configured to receive and support the plurality of sleepers or ballast on which the plurality of sleepers rests. The assembly comprising the support slab, the portion of railway track, the plurality of sleepers and / or ballast forms the deck of the railway bridge.

[0005] Railway bridges are generally designed with significant dimensions, in particular the thickness of the slab which determines their capacity to resist the passage of a vehicle such as a train.

[0006] Over time, railway bridges require significant maintenance. In particular, water can stagnate on the concrete supporting the ballast or directly on the sleepers, which can cause deterioration of the concrete. To remedy this waterproofing problem, it is necessary to remove all the track on the bridge, re-waterproof it and reinstall the track on the bridge. Such maintenance is time-consuming, expensive, restrictive and stops traffic that is operating on the track for the duration of the maintenance.

[0007] Furthermore, it is known that the deck of the railway bridge is placed on support devices generally containing rubber or an elastomer so as to support and absorb the forces transmitted by the deck.

[0008] However, these bearing devices wear out over time and need to be maintained and replaced when they show excessive wear. Replacing the bearing devices requires lifting the deck, replacing the worn bearing devices with new ones and reinstalling the deck. Such maintenance is time-consuming, expensive, restrictive and stops the traffic that is operating on the track for the duration of the maintenance.

[0009] The invention thus aims to eliminate at least some of these drawbacks, in particular to reduce heavy maintenance operations on bridges. PRESENTATION OF THE INVENTION

[0010] The invention relates to a bridge comprising a support slab. The support slab comprises an upper face arranged to support a traffic lane and a lower face opposite the upper face. Said bridge further comprises at least one support member for said bridge and a plurality of anchor rods secured on the one hand to the lower face of the support slab so as to improve its mechanical strength, and on the other hand to said support member, said support slab being at least partially made of concrete and the plurality of anchor rods being at least partially made of steel, said support slab at least partially covering said anchor rods and said support member at least partially covering said anchor rods.

[0011] The support member and the plurality of steel anchor rods are configured to allow for the absorption of forces, in particular horizontal forces, from the support slab. Thus, such a bridge is particularly suitable for supporting rails. Furthermore, the cooperation of the support slab, the anchor rods and the support member allows for easier maintenance of the bridge. Indeed, said cooperation allows for easy jacking of the bridge in the event of a need, for example, to replace one of the elements of said bridge during maintenance. Said anchor rods require, due to their at least partial embedding, little or no specific monitoring and maintenance since they are little or not exposed to external elements such as water or atmospheric air.

[0012] Advantageously, the support slab comprises a proportion of ultra-high performance fiber-reinforced concrete.

[0013] Ultra-high performance concrete (UHPC) has a high binder content which leads to the absence of capillary porosity in the support slab. Thus, UHPC prevents water infiltration into the support slab and its stagnation. It thus increases the lifespan of the bridge's waterproofing, at least twice as long compared to a conventional bridge. Ultra-high performance concrete (UHPC) includes internal reinforcements which advantageously allow mechanical forces to be transmitted to the reinforcement members at least partially made of self-patenting steel. This improves the transfer of mechanical forces between the reinforcement members and the internal reinforcements.

[0014] Advantageously, the support slab comprises a slab body and a sealing layer, the sealing layer covering the slab body and being interposed between the latter and said traffic lane, said sealing layer forming the proportion of ultra-high performance fiber-reinforced concrete of the support slab.

[0015] The ultra-high performance fiber-reinforced concrete waterproofing layer protects the concrete slab body, in particular from water ingress and stagnation. It thus increases the lifespan of the bridge waterproofing, at least twice as long compared to a conventional bridge. Also, the waterproofing layer eliminates the work involved in maintaining and replacing the bridge waterproofing, namely removing the entire track on the bridge, redoing the waterproofing and reinstalling the track on the bridge.

[0016] Advantageously, the sealing layer has a thickness of between 3 cm and 5 cm.

[0017] According to one variant, the support slab is made entirely of ultra-high performance fiber-reinforced concrete.

[0018] Advantageously, the bridge further comprises at least one layer of wedging mortar interposed between the slab and the support member.

[0019] Advantageously, the layer of wedging mortar has a thickness of between 3 and 5 cm.

[0020] The layer of wedging mortar allows for the absorption of vertical forces that the bridge is subjected to.

[0021] Advantageously, the plurality of anchor rods is distributed over the width of the support slab and the support member.

[0022] Advantageously, each anchor rod of the plurality of anchor rods has a first half embedded in the support slab and a second half embedded in the support member.

[0023] Advantageously, the support slab is entirely embedded in said support member.

[0024] The at least partial embedding in the support member makes it possible to dispense with support devices made at least partially of rubber and therefore with their upkeep and maintenance. In particular, the replacement of said support devices requires lifting the support slab to replace the support device to be changed with a new one, which causes traffic to stop on the bridge.

[0025] Advantageously, the bridge further comprises reinforcement bars, the support slab at least partially covering the anchor rods and the reinforcement bars.

[0026] Other characteristics and advantages of the invention will appear during the description which follows, given with reference to the appended figures given as non-limiting examples and in which identical references are given to similar objects. PRESENTATION OF THE FIGURES

[0027] The invention will be better understood on reading the following description, given in by way of example, and referring to the following figures, given as non-limiting examples, in which identical references are given to similar objects.

[0028] [Fig.l] is a front and sectional view of a bridge according to the invention, comprising a support slab at least partly enclosing a plurality of anchor rods, said plurality of anchor rods being further enclosed in a support member;

[0029] [Fig.2] is an exploded perspective view of the bridge of [Fig.l], in which the a plurality of anchor rods is embedded in the support member; and

[0030] [Fig. 3] is a perspective view of the bridge of [Fig. 1], in which the plurality of anchor rods supplemented by a plurality of reinforcement bars create an embedment between the support member and in the support slab.

[0031] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0032] The invention relates to a bridge 2, in particular a railway bridge, allowing the support of a traffic lane 1, in particular a railway track, allowing the circulation of vehicles, in particular railway vehicles.

[0033] It goes without saying that the invention is not limited to the railway field but applies to any type of bridge intended to receive a traffic lane, road or pedestrian for example.

[0034] As illustrated in Figures 1 to 3, the traffic lane 1 comprises two parallel longitudinal rails 10 fixed on a plurality of sleepers arranged perpendicular to the rails 10.

[0035] The sleepers rest on ballast (not shown) which supports and stabilizes the traffic lane 1. Of course, the sleepers can rest directly on the bridge 2, as illustrated in the figures.

[0036] The bridge 2 comprises a support slab 20.

[0037] The support slab 20 comprises an upper face and a lower face. The upper face is arranged to support a portion of the traffic lane 1 and the lower face is opposite the upper face. For example, the support slab 20 may have a length of up to 15m, a width of between approximately 3.5m and 10m and a thickness of up to 125cm depending on the span of the bridge.

[0038] According to the invention, the support slab 20 is at least partially made of concrete.

[0039] Thus, the support slab 20 may have a proportion of concrete, and in particular a proportion of ultra-high performance fiber-reinforced concrete (UHPC). A UHPC has, in a known manner, a resistance ranging from 130 to 250 MPa in compression and from 20 to 50 MPa in flexural tension. In addition, BFUP has a high binder content which leads to the absence of capillary porosity.

[0040] As illustrated in Figures 1 to 3, the support slab 20 may comprise a slab body 200 and a sealing layer 201.

[0041] The sealing layer 201 covers the slab body 200 and is interposed between said slab body 200 and the traffic lane 1. The sealing layer 201 is made of ultra-high performance fiber-reinforced concrete and forms the proportion of ultra-high performance fiber-reinforced concrete of the support slab 20.

[0042] The sealing layer 201 has a thickness of between 3 cm and 5 cm.

[0043] Such a thickness makes it possible to ensure good implementation of the sealing layer 201 while limiting the risks of cracking and the costs, in particular the costs linked to the manufacture of said sealing layer 201.

[0044] The waterproofing layer 201 made of ultra-high performance fiber-reinforced concrete makes it possible to protect the slab body 200, for example made of concrete, in particular from water ingress and stagnation. The waterproofing layer 201 thus makes it possible to increase the lifespan of the waterproofing of the bridge 2, at least twice as long compared to a conventional bridge.

[0045] The sealing layer 201 makes it possible to avoid the work generated by the maintenance and replacement of the sealing of the bridges, namely removing all the track present on the bridge, redoing the sealing and reinstalling the track on the bridge.

[0046] Alternatively, the support slab 20 may be made entirely of concrete, in particular, of ultra-high performance concrete.

[0047] The support slab 20 made of ultra-high performance fiber-reinforced concrete makes it possible to prevent water infiltration into the support slab 20 and its stagnation. The UHPFRC thus makes it possible to increase the lifespan of the waterproofing of the bridge 2, at least twice as long compared to a conventional bridge.

[0048] The BFUP support slab 20 makes it possible to avoid the work involved in maintaining and replacing the waterproofing of bridges, namely removing all the track present on the bridge, redoing the waterproofing and reinstalling the track on the bridge.

[0049] It goes without saying that the support slab 20 could be made of a concrete mixture comprising, for example, BFUP and ordinary concrete.

[0050] The bridge 2 further comprises a plurality of anchor rods 21.

[0051] The plurality of anchor rods 21 is at least partially made of steel.

[0052] In particular, the plurality of anchor rods 21 may have a proportion of steel, or be entirely made of steel.

[0053] The plurality of anchor rods 21 is secured on the one hand to the lower face of the support slab 20 so as to improve its mechanical resistance.

[0054] In particular, the support slab 20 at least partially covers the plurality of rods. anchor rods 21. Referring to [Fig.l], the plurality of anchor rods 21 is distributed across the width of the support slab 20, and the latter encases a first half of each of the anchor rods 21.

[0055] The plurality of anchor rods 21 is secured to the support slab 20 so as to improve the mechanical strength thereof. In particular, and as shown in [Fig.l], the plurality of anchor rods 21 is partially coated by the support slab 20. Here, each half of each anchor rod 21 is coated in the support slab 20.

[0056] With reference to [Fig.l], the bridge 2 comprises eighteen anchor rods 21 coated across the width of the support slab 20.

[0057] The bridge 2 according to the invention further comprises at least one support member 22 for the bridge 2 on its support.

[0058] The support member 22 is for example made of reinforced concrete.

[0059] Advantageously, the support member 22 comprises support devices 5 comprising rubber or any other elastomer. They make it possible to absorb the forces transmitted by the plurality of anchor rods 21, towards the support member 22.

[0060] The plurality of anchor rods 21 is secured on the other hand to the support member 22.

[0061] In particular, the support member 22 at least partially covers the plurality of anchor rods 21. With reference to [Fig. 1], the plurality of anchor rods 21 is distributed over the width of the support member 22, and the latter covers a second half of each of the anchor rods 21.

[0062] The plurality of anchor rods 21 is secured to the support member 22 so as to improve the mechanical strength thereof. In particular, and as shown in [Fig. 1], the plurality of anchor rods 21 is partially coated by the support member 22. Here, each other half of each anchor rod 21 is coated in the support member 22.

[0063] With reference to [Fig.l], the bridge 2 comprises eighteen anchor rods 21 coated over the width of the support member 22.

[0064] It is understood that the number of anchor rods 21 depends on the width of the support slab 20 and the support member 22. Indeed, the wider the support slab 20 and the support member 22 are, the higher the number of anchor rods 21 will be and vice versa.

[0065] The bridge 2 may further comprise at least one layer of wedging mortar 3. The layer of wedging mortar 3 is interposed between the support slab 20 and the support member 22.

[0066] Each anchor rod 21 extends on either side of the layer of wedging mortar 3. In particular, half of each anchor rod 21 extends on the one hand from the layer of wedging mortar 3 in the direction of the support slab 20 and the other half of each anchor rod 21 extends on the other hand from the layer of wedging mortar 3, in the direction of the support member 22.

[0067] The layer of wedging mortar 3 has a thickness of between 3 cm and 5 cm.

[0068] The total embedding of the anchor rods 21 in the support slab 20 and in the support member 22 allows direct contact between the support slab 20 and the layer of wedging mortar 3 and between the layer of wedging mortar 3 and the support member 22. The layer of wedging mortar 3 allows the vertical forces generated on the bridge 2 to be taken up and therefore increases its mechanical strength and therefore reinforces the structure of the bridge 2.

[0069] As shown in [Fig. 3], the bridge 2 further comprises reinforcement bars. The support slab 20 at least partially encases the anchor rods 21 and the reinforcement bars. In particular, the support slab 20 is entirely embedded in the support member 22 by means of the anchor rod system 21 supplemented by the reinforcement bars connecting the support slab 20 to the support member 22.

Claims

Claims

1. Bridge (2) comprising a support slab (20) having an upper face arranged to support a traffic lane (1) and a lower face opposite the upper face, said bridge (2) further comprising at least one support member (22) of said bridge (2) and a plurality of anchor rods (21) secured on the one hand to the lower face of the support slab (20) so as to improve the mechanical strength thereof, and on the other hand to said support member (22), said support slab (20) being at least partially made of concrete and the plurality of anchor rods (21) being at least partially made of steel, said support slab (20) at least partially coating said anchor rods (21) and said support member (22) at least partially coating said anchor rods (21).

2. A bridge (2) according to claim 1, wherein the support slab (20) comprises a proportion of ultra-high performance fiber-reinforced concrete.

3. A bridge (2) according to claim 2, wherein the support slab (20) comprises a slab body (200) and a sealing layer (201), the sealing layer (201) covering the slab body (200) and being interposed between the latter and said traffic lane (1), said sealing layer (201) forming the ultra-high performance fiber-reinforced concrete proportion of the support slab (20).

4. Bridge (2) according to claim 3, in which the sealing layer (201) has a thickness of between 3cm and 5cm.

5. Bridge (2) according to any one of claims 1 and / or 2, wherein the support slab (20) is made entirely of ultra-high performance fiber-reinforced concrete.

6. Bridge (2) according to any one of claims 1 to 5, further comprising at least one layer of wedging mortar (3) interposed between the support slab (20) and the support member (22).

7. Bridge (2) according to claim 6, in which the layer of wedging mortar (3) has a thickness of between 3 cm and 5 cm.

8. Bridge (2) according to any one of claims 1 to 7, wherein the plurality of anchor rods (21) is distributed over the width of the support slab (20) and the support member (22).

9. A bridge (2) according to any one of claims 1 to 8, wherein each anchor rod of the plurality of anchor rods (21) has a first half embedded in the support slab (20) and a second half embedded in the bearing member (22).

10. Bridge (2) according to any one of claims 1 to 9, further comprising reinforcement bars, the support slab (20) at least partially covering the anchor rods (21) and the reinforcement bars.

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