METHOD FOR THE PRODUCTION OF A DECK SLAB FOR A BRIDGE
“A method for producing a construction section of a deck slab for a bridge includes the following operations: producing a bottom layer composed of a segment and having cross beams, which are arranged in the transverse direction in regard to the longitudinal axis of the longitudinal bridge girder, from reinforced concrete; transporting the bottom layer having the cross beams for a construction section of the deck slab using a conveyor device from an assembly site to an installation site and lowering it into the installation position; producing a top concrete layer for a construction section of the deck slab on the bottom layer; removing the bottom layer having the cross beams for a construction section of the deck slab from the conveyor device and moving the conveyor device away from the installation site.”
The invention relates to a method for producing a deck slab using a conveyor device with a top concrete layer produced at the installation site for a bridge as well as deck slabs produced according to this method.
The production of a deck slab for a bridge using a formwork carriage is described in the “Handbuch Brücken”, section 9.3.2 “Schalung and Fertigung Betonfahrbahnplatte”, published by Gerhard Mehlhorn with the Springer-Verlag in the year 2010. There are mounted support constructions on the longitudinal bridge girder. On the top surface of the support construction, there are installed launching gantries, which provide movement of a formwork carriage in the longitudinal direction of the bridge. For the production of a construction section of the deck slab, the formwork carriage is conveyed to the installation site, being fixed there. Subsequently, the formwork for the construction section to be erected of the deck slab is moved into the scheduled position, the reinforcement is laid and concrete is being introduced. After the concrete has hardened, the formwork is then lowered and the formwork carriage is moved to a further installation site. A construction section usually has a length of 15 m to 35 m. An advantage of this method is that in the final condition, there will be present only a few sectional joints within the deck slab. A disadvantage of this method is the slow construction progress as the assembly of the formwork and the laying of the reinforcement are carried out at the installation site and the formwork will only then be removed from the formwork carriage if the concrete of the construction section last produced has sufficient rigidity. The production of the construction sections using this method is usually realized within one week, wherein the weekend is used for the concrete to harden.
The production of the deck slab for a bridge using a formwork carriage, which may be moved directly on the longitudinal bridge girder, is described in the DE 195 44 557 C1. In this method, the effort for producing the support constructions and for mounting the launching gantries is being omitted. Also in this method, there is given the disadvantage of the slow construction progress of a weekly schedule for the production of a construction section of the deck slabs.
In DE 25 20 105 A1 there are described prefabricated elements made from reinforced concrete, which are composed of a prefabricated bottom slab and at least one cross beam. In the prefabricated bottom slab, there are arranged the lower transverse reinforcement and the lower longitudinal reinforcement of the deck slab. The prefabricated elements are moved at the installation site using a crane onto the longitudinal bridge girder. Then the splice reinforcement for the lower longitudinal reinforcement, the upper longitudinal reinforcement and the upper transverse reinforcement is being laid. In the next operation, the top concrete layer is then applied. Moving the prefabricated elements at the installation site, sealing the joints in-between the individual prefabricated elements and laying of the reinforcement are time-consuming operations, which is disadvantageous for a fast construction progress in the production of the deck slab.
To accelerate construction progress, there is described in WO/2016/187634 A1 a method for producing a deck slab having prefabricated bottom slabs and a top concrete layer arranged above made from in-situ concrete for a bridge having a longitudinal bridge girder. In this method there is produced a conveyor device, which may be moved on support constructions, which are mounted on the top surface of the longitudinal bridge girder, in the longitudinal direction of the bridge. Using the conveyor device, the prefabricated slabs are transported from an assembly site to an installation site. At the installation site, the prefabricated slabs are lowered until the edges of the prefabricated slabs are supported on the longitudinal bridge girder. Upon lowering, the prefabricated slabs are still attached at the conveyor device by means of tendons. Subsequently, there is laid a reinforcement and a top concrete layer is applied. After the top concrete layer has hardened, the anchors of the prefabricated slabs are then removed from the tendons. Subsequently, the conveyor device is then moved to an assembly site to optionally pick up further prefabricated slabs. The disadvantage of the method described in WO/2016/187634 A1 is the anchoring of the tendons within the prefabricated slabs. The load capacity of the anchors of the tendons is low if anchoring of the tendons is realized within the prefabricated slabs. The load capacity of the anchors of the tendons is sufficient if anchoring of the tendons is realized at the bottom surface of the prefabricated slabs. Anchoring at the bottom surface of the prefabricated slabs, however, requires an additional operation for removing the anchors from the bottom surface of the prefabricated slabs. In the method described in WO/2016/187634 A1 it is furthermore disadvantageous that the forces arising within the tendons cause bending moments within the prefabricated slabs, which lead to high bending stress within the thin prefabricated slabs. A further disadvantage of the method described in WO/2016/187634 A1 is that the tendons may only be removed from the conveyor device after the top concrete layer has sufficient rigidity. Awaiting the hardening phase of the top concrete layer is disadvantageous for a rapid construction progress in the production of the deck slab.
Also the documents AT 520 614 A1 and KR 101 866 466 B each show methods for the production of deck slabs of a bridge. There are respectively positioned slab-like elements onto longitudinal girders of the bridge, whereupon a reinforce concrete slab will be produced thereon. The methods of these publications have the same disadvantages as the method of the publication WO/2016/187634 A1.
The publication JP 2004 116060 A discloses a method, in which there are laid prefabricated cross beams made from reinforced concrete on a longitudinal bridge girder in order to produce a deck slab. Subsequently, there are laid prefabricated slabs made from reinforced concrete on the cross beams. In the next work step, a reinforcement is laid on the prefabricated slabs and then there is applied a top concrete layer. Laying the individual cross beams and subsequently laying the individual prefabricated slabs at the installation site is time consuming and, hence, disadvantageous for a rapid construction progress.
It is thus the task of the present invention to create a method for the production of a deck slab, which provides for a faster construction progress than with methods known performing formwork and/or reinforcement works at the installation site and in which in the construction condition an easier anchoring of the tendons is possible and in which the bending stress arising in the construction condition may be better absorbed than with the method known using prefabricated bottom slabs.
The task is solved by a method for the production of a construction section of a deck slab for a bridge, wherein:
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- a—there is produced at an assembly site from reinforced concrete a bottom layer composed of at least one segment and having cross beams, which are arranged at an angle of between 70° and 90° to a longitudinal axis of a longitudinal bridge girder;
- b—the bottom layer having the cross beam is transported for the construction section of the deck slab using at least one conveyor device from the assembly site to an installation site and lowered into an installation position;
- c—there is laid onto the bottom layer having the cross beams a top concrete layer for the construction section of the deck slab, wherein there is optionally laid a reinforcement to be arranged within the top concrete layer before the application of the top concrete layer;
- d—the bottom layer having the cross beam is removed for the construction section of the deck slab from the conveyor device before or after the application of the top concrete layer.
- e—the conveyor device is moved away from the installation site and optionally conveyed to the assembly site in order to pick up there a further bottom layer having cross beams for a construction section of the deck slab.
To accelerate constructional progress, it may be advantageous to configure the bottom layer having the cross beams or a segment of the bottom layer to be load-bearing such that it may absorb its own weight and the weight of the top concrete layer and introduce these into the longitudinal bridge girder. In this case, the conveyor device may be moved away from the installation site immediately upon lowering of the bottom layer.
To enlarge the load capacity of the bottom layer, there are arranged cross beams within the bottom layer. These cross beams may be laid at the assembly site onto a formwork or a scaffolding before the production of the bottom layer. The cross beams are advantageously equipped with starter bars. In this way, a load-bearing connection of the cross beams to the bottom layer and the top concrete layer is being ensured. There may be arranged anchors for lifting the bottom layer and cladding tubes for tendons within the cross beams. The cross beams may be equipped with steel slabs to provide for a structural steel connection of the cross beams to the bottom layer or of cross beams, which are arranged in different segments. The connection between cross beams and prefabricated slabs or between two cross beams, respectively, which are arranged in different segments of the bottom layer, may be produced by welding, screwing or by starter bars and hardcore filling.
There may be arranged terminal anchors and deflection points for tendons in a cross beam. It may be advantageous to produce the top concrete layer in two operations. The second part of the top concrete layer is only produced after the first part of the top concrete layer has reached a predefined minimum rigidity. In this case, the bottom layer may be removed from the conveyor device, after the first part of the top concrete layer has reached a predefined minimum rigidity. The bottom layer may be produced having haunches and variable thickness. A segment of a bottom layer may be shifted transversally to the longitudinal axis of the longitudinal bridge girder and/or rotated in regard thereto after it has been raised at the assembly site, may be transported from the assembly site to the installation site in this shifted and/or rotated position and may then be installed at the installation site by cross shift and/or rotation into the scheduled installation position. It may be advantageous to transport the segments of the bottom layer for a construction section of the deck slabs in several transport operations from the transfer site to the installation site.
In an particularly advantageous embodiment of the present invention there is connected a bottom layer composed of at least two segments and having cross beams at the assembly site by a first top concrete layer or by other means such as, for example, screw connections, to a bottom layer composed of one segment.
In a particularly advantageous embodiment of the present invention the bottom layer having cross beams is produced at the assembly site from a segment and transported using a conveyor device composed of a front part, a rear part and at least two longitudinal girders from the assembly site to the installation site. The front part and the rear part of the conveyor device are connected to one another by means of the at least longitudinal girders. The conveyor device is moved along the bridge on support constructions. The bottom layer having the cross beams during transport from the assembly site to the installation site is arranged between the front part and the rear part and underneath the longitudinal girder of the conveyor device. Underneath the bottom layer having cross beams, there must not be arranged any constructions elements for connecting the front part and the rear part of the conveyor device during the lowering operation at the installation site. During the transport of the bottom layer from the assembly site to the installation site, it may be useful to connect the front and the rear part of the conveyor device by way of construction elements such as, e.g., ropes, which are arranged underneath the bottom layer having the cross beams, in order to enlarge the rigidity of the conveyor device.
In a preferred embodiment of the invention the conveyor device is produced from a front part, a rear part and at least two longitudinal girders. To shift the conveyor device in order to enable the production of the next construction section of the deck slab, the front part and the rear part of the conveyor device are moved on support constructions. The front and the rear part of the conveyor device are connected to one another by at least two longitudinal girders. At the longitudinal girders, there is installed a construction by means of which lifting and/or lowering of the bottom layer having cross beams, which is arranged between the front and the rear part and underneath the longitudinal girders of the conveyor device, is made possible.
The conveyor device may be configured as a frame construction or as a truss construction.
Using the method according to the invention it is made possible to produce the deck slab of bridges that are straight in plan view and have any curvature. Using the method according to the invention it is made possible to produce deck slabs having any transversal inclination and having variable width.
In a further aspect of the invention there is created a construction section of a deck slab, comprising a bottom layer composed of at least one segment and having cross beams, which are arranged at an angle of between 70° and 90° to the longitudinal axis of a longitudinal bridge girder, wherein the bottom layer is produced from reinforced concrete and wherein onto the bottom layer having cross beams there is applied a top concrete layer for the construction section of the deck slab, which optionally has reinforcement.
Further details, features and advantages of the invention become obvious from the explanations given below of exemplary embodiments schematically depicted in the drawings
The first embodiment of the method according to the invention is depicted in the
In the longitudinal direction of the bridge 4, there are shifted longitudinal edge beams 28 to simplify in a later method step the concreting works when introducing the top concrete layer 3. The cross beams 21 as well as the longitudinal edge beams 28 are equipped with starter bars. The deck slab 1 in this embodiment example has two haunches in the final condition.
These haunches are to be reproduced already in the production of the cross beams 21 and in the production of the formwork 23.
In the next method step, concrete for the production of the bottom layer 2 is introduced according to
According to
The bottom layer 2 having the cross beams 21 and the longitudinal edge beams 28 is lifted from the conveyor device 10 after the concrete has hardened and is then transported from the assembly site 31 to the installation site 32.
The upper end points 12 of the tendons 11 are attached to the conveyor device 10. The conveyor device 10 is positioned at the installation site 32 such that the recesses 16 are arranged above the bracing means 6 arranged at the top surface 18 of the longitudinal bridge girder 5. The wheels 8 may be blocked after the precise positioning of the conveyor device 10 at the installation site 32 to prevent the conveyor device 10 from rolling away. Fixing the conveyer device 10 at the installation site 32 may also be realized by way of a temporary connection of the conveyor device 10 to the longitudinal bridge girder 5 or by other measures.
In
A sectional view corresponding to
According to
According to
A bridge 4, which comprises two abutments 33, five pillars 34 and one longitudinal bridge girder 5, is depicted in
According to
In this embodiment example, the ribbed base plate 26 is attached to the conveyor device 10 by means of tendons 11, while the top concrete layer 3 is being applied. Only once the top concrete layer 3 has hardened, the ribbed base plate 26 is removed from the conveyor device 10. Alternatively, it would also be possible to configure the ribbed base plate 26 to be so rigid such that it would be able to carry its own net weight and the weight of the top concrete layer 2. A ribbed base plate 26 such configured would make it possible that the connection between the ribbed base plate 26 and the conveyor device 10 is released immediately after the ribbed base plate 26 has been lowered and the conveyor device 10 could be moved back to the assembly site 31. This would enable the acceleration of the production of the deck slab 1. In this case, however, there should be installed makeshift lanes 7 on the ribbed base plate 26 such that it would be possible for the conveyor device 10 to drive on the ribbed base plate 26.
The assembly site 31 is in the first embodiment example situated on an abutment 33. It may also be advantageous to move the assembly site 31 onto the bridge 4, after the first sections of the deck slab 1 have been produced. It may also be advantageous to provide more than one assembly site 31 to enable longer hardening of the concrete of the bottom layer 2. According to
In this exemplary embodiment, the weight of the ribbed base plate 26 on the top concrete layer 3 is introduced from the wheels 8 into the longitudinal bridge girder 5. Alternatively, it would also be possible to install supports and to lift the wheels 8 before the top concrete layer 3 is introduced. This may also be of advantage as the supports may be accommodated in the recesses 16 having smaller dimensions than the recesses 16 required for the accommodation of the wheels 8.
A second embodiment of the method according to the invention is depicted in the
After the concrete of the bottom layer 2 has hardened, a conveyor device 10 will be moved to the assembly site 31, the three segments 17 of the bottom layer 2 will be attached using tendons 11 to the conveyor device 10, will be lifted and transported to the installation site 32. According to
For this reason it is also not possible to lay the entire reinforcement at the assembly site 31. The upper transverse reinforcement required for connecting the cantilevering slabs and the slab arranged between the steel girders 9 of the longitudinal bridge girder 5 may only be laid at the installation site 32 after the bottom layer 2 has been lowered.
A bridge 4 comprising two abutments 33, five pillars 34 and one longitudinal bridge girder 5 is depicted in the illustrations
According to
The assembly site 31 is situated in this embodiment example on an abutment 33. It may also be advantageous that the assembly site 31 is moved to the bridge 4 after the first sections of the deck slab 1 have been produced.
According to
A third embodiment of the method according to the invention is depicted in the illustrations
During transport to the installation site 31, the segment 17 arranged between the steel girders 9 is in a raised position to prevent collision with the bracing means 6 welded to the steel girders 9 and the construction sections already completed of the deck slab 1. The segment 17 depicted in
At the installation site 32, the three segments 17 of the bottom layer 2 are brought into the scheduled position. According to
According to
According to
According to
A fourth embodiment of the method according to the invention is depicted in the illustrations
In the next working step according to
The detail E of
An alternative embodiment for producing a flexurally rigid connection of the two cross beams 21 is shown in the
A fifth embodiment of the method according to the invention is depicted in the illustrations
According to
In the next working step, there is laid a reinforcement onto the bottom layer 2 and there is produced a first top concrete layer on the prefabricated slabs 50. The three segments 17 of the bottom layer 2 are joined to one segment 17 by the first top concrete layer 3.
According to
A bridge 4 comprising two abutments 33, five pillars 34 and one longitudinal bridge girder 5 is depicted in the illustrations
According to
Immediately following the lowering operation, the lower end points 13 of the tendons 11 may be released from the cross beams 21 and the conveyor device 10 may be moved from the installations site 32 back to the assembly site 31 to pick up there a further bottom layer 2 having cross beams 32 and a first top concrete layer 3 for a further construction section of the deck slab 1.
In this embodiment example it is particularly advantageous that at the installation site 32 it is not necessary to wait for the top concrete layer 3 to harden. The conveyor device 10 may be moved away from the installation site 32 immediately after the bottom layer 2 having the cross beams 21 and the first top concrete layer 3 has been lowered. In this way it is possible to produce one construction section of the deck slab 1 per day. Producing the second top concrete layer 3 is independent of the bottom layer 2 having cross beams 31 and first top concrete layer being laid and may be realized at any point of time.
According to
A sixth embodiment of the method according to the invention is depicted in the illustrations
The bottom layer 2 having cross beams 21 is produced at the assembly site 31 on a framework 23. The bottom layer 2 having cross beams 21 is composed in this embodiment example of one segment 17, as the three cross beams 21 extend across the entire width of the deck slab 1 to be produced and, in this way, a continuous construction component is being developed.
According to
- 1 deck slab
- 2 bottom layer
- 3 top concrete layer
- 4 bridge
- 5 longitudinal bridge girder
- 6 bracing means
- 7 lane
- 8 wheel
- 9 steel girder
- 10 conveyor device
- 11 tendon
- 12 upper end point of a tendon
- 13 lower end point of a tendon
- 14 anchor
- 15 device
- 16 recess
- 17 segment of a bottom layer
- 18 top surface of a longitudinal bridge girder
- 19 bottom surface of a bottom layer
- 20 mounting girder
- 21 cross beam
- 22 strip
- 23 formwork
- 24 gap
- 25 bottom surface of a bottom layer
- 26 ribbed base plate
- 27 prefabricated beam
- 28 longitudinal edge beam
- 29 support construction
- 30 launching gantry
- 31 assembly site
- 32 installation site
- 33 abutment
- 34 pillar
- 35 steel slab
- 36 threaded nut
- 37 sleeve tube
- 38 cladding tube
- 39 bracing wire
- 40 prestressed concrete beam
- 41 screw connection
- 42 steel panel
- 43 front slab
- 44 front part of a conveyor device
- 45 rear part of a conveyor device
- 46 longitudinal girder of a conveyor device
- 47 prefabricated element
- 48 hollow piston jack
- 49 frame construction
- 50 prefabricated slab
- 51 piston
Claims
1-14. (canceled)
15. A method for the production of a construction section of a deck slab for a bridge, wherein:
- a—there is produced at an assembly site, from reinforced concrete, a bottom layer composed of one or more segments and having cross beams, which are arranged at an angle of between 70° and 90° to a longitudinal axis of a longitudinal bridge girder;
- b—the bottom layer having the cross beams is transported for the construction section of the deck slab, using one or more conveyor device, from the assembly site to an installation site and lowered into an installation position;
- c—there is laid onto the bottom layer having the cross beams a top concrete layer for the construction section of the deck slab, wherein there is laid a reinforcement to be arranged within the top concrete layer before the application of the top concrete layer;
- d—the bottom layer having the cross beams is removed for the construction section of the deck slab, from the conveyor device, before or after the application of the top concrete layer; and
- e—the conveyor device is moved away from the installation site and conveyed to the assembly site in order to pick up there a further bottom layer having cross beams for a construction section of the deck slab.
16. A method according to claim 15, wherein the bottom layer having the cross beams is removed for the construction section of the deck slab after being lowered from the conveyor device, the conveyor device is moved away from the installation site and only then the top concrete layer is being applied thereupon.
17. A method according to claim 15, wherein the cross beams are produced in advance as prefabricated beams, are laid on the assembly site and only then the bottom layer is being produced.
18. A method according to claim 15, wherein the bottom layer is produced from prefabricated slabs and the cross beams are connected to the prefabricated slabs by way of welding, screwing, or starter bars.
19. A method according to claim 15, wherein there are arranged within the cross beams anchors for lifting the bottom layer and the cross beams and/or there is arranged in one of the cross beams a tendon in the longitudinal direction of that cross beam.
20. A method according to claim 15, wherein there are connected to one another two cross beams, which are arranged in different segments, by way of a structural steel connection.
21. A method according to claim 15, wherein the top concrete layer is applied in two operations and a second part of the top concrete layer is produced only after a first part of the top concrete layer has reached a predetermined minimum rigidity.
22. A method according to claim 15, wherein the bottom layer and/or the cross beams are produced having one or more haunches.
23. A method according to claim 15, wherein the bottom layer and/or the cross beams are produced having a variable thickness.
24. A method according to claim 15, wherein a segment of the bottom layer having cross beams is shifted transversally to the longitudinal axis of the longitudinal bridge girder and/or rotated in regard thereto after being raised at the assembly site, is transported from the assembly site to the installation site in this shifted and/or rotated position and is then installed at the installation site by cross shift and/or a rotation into the scheduled installation position.
25. A method according to claims 15, wherein there is connected at the assembly site a bottom layer composed of two or more segments and having cross beams via a first top concrete layer or an alternative technique of connection to a bottom layer comprising one segment and having cross beams.
26. A method according to claim 15, wherein:
- the bottom layer having the cross beams is produced as a segment;
- the conveyor device is made of a front part, a rear part and two or more longitudinal girders;
- the front part and the rear part of the conveyor device are connected to one another by the two or more longitudinal girders;
- the front part and the rear part of the conveyor device are moved on support constructions;
- the bottom layer having the cross beams is arranged between the front part and the rear part and underneath the longitudinal girders of the conveyor device; and
- there will not be arranged any construction elements for connecting the front part and the rear part of the conveyor device underneath the bottom layer having the cross beam during the lowering operation at the installation site.
27. A method according to claim 15, wherein:
- the conveyor device is made of a front part and a rear part and two or more longitudinal girders;
- wherein for shifting the conveyor device in order to produce a next construction section of a deck slab, the front part and the rear part of the conveyor device are moved on support constructions in the longitudinal direction of the bridge;
- wherein the front part and the rear part of the conveyor device are connected to one another by the two longitudinal girders; and
- there is created at the longitudinal girders a construction for lifting and/or lowering the bottom layer having the cross beams, which is arranged between the front part and the rear part and underneath the longitudinal girders of the conveyor device.
28. (canceled)
29. A method according to claim 15, wherein the bottom layer is produced from prefabricated elements, wherein the prefabricated elements comprise two or more prefabricated slabs and one cross beam connecting the at least two prefabricated slabs with each other, wherein the prefabricated elements are laid on mounting girders at the assembly site and the prefabricated elements are connected to a segment.
Type: Application
Filed: Mar 25, 2021
Publication Date: May 25, 2023
Inventors: Johann KOLLEGGER (Klosterneuburg), Michael RATH (Neunkirchen), Stephan FASCHING (Wien), Kerstin GASSNER (Mautern an der Donau), Franz UNTERMARZONER (Wien)
Application Number: 17/995,375