Apparatus and method for monitoring pier head deflection in constructing and dismantling bridges

Abstract

The invention relates to a method (100) for monitoring the pier head deflection (9) of a bridge pier (208) and / or the positional deviation (39) of a bridge superstructure (206), in particular in the construction and / or dismantling of bridges (202) using the incremental launching method and / or by means of a launching gantry.The invention further relates to a device (1) for monitoring the pier head deflection (9) of a bridge pier (208) and / or the positional deviation (39) of a bridge superstructure (206), comprising a plumb laser (7) configured to emit a vertical laser beam (11); a laser plumb disk (13) preferably having a measuring grid (33); a plumb disk fixing (15) configured to fix the laser plumb disk (13) horizontally projecting from a pier head (218) of the bridge pier (208) onto the pier head (218) and above the plumb laser (7), so that the laser beam (11) of the plumb laser (7) can be projected onto the laser plumb disk (13); and a camera unit (19) for capturing images and / or videos of the laser beam (11) striking the laser plumb disk (13).

Description

[0001] The invention relates to a method for monitoring the deflection of the pier head of a bridge pier and / or the positional deviation of a bridge superstructure, in particular in the construction and / or dismantling of bridges using the incremental launching method and / or by means of a launching gantry.

[0002] In bridge construction, especially for bridges spanning wide valleys or broad rivers and / or those with limited or no access from below due to their height, the incremental launching method has become the preferred construction technique. In this method, a bridge superstructure is prefabricated section by section behind an abutment, which forms one of the bridge's two longitudinal ends, on a pre-assembly site. It is then launched longitudinally onto pre-constructed bridge piers. This launching process is also known as incremental launching. The incremental pre-assembly and longitudinal launching are repeated until the entire length of the bridge superstructure is complete and the first segment of the superstructure has reached the other abutment.

[0003] A launching nose is often attached to the foremost segment of the bridge superstructure in the insertion direction (longitudinal direction of the future bridge). The launching nose is typically a tapered steel structure. It reduces the cantilevered or unsupported length of the bridge superstructure, usually made of reinforced concrete, during the insertion process. This allows the launching nose to be supported by a bridge pier while the bridge superstructure has only been inserted over part of its span.

[0004] Other methods for constructing and / or dismantling bridges employ launching gantry systems, which are also pushed onto bridge piers. The use of a launching gantry allows for the section-by-section dismantling of large bridges in sensitive areas where falling debris must be avoided.

[0005] When structural components, such as a bridge superstructure, a launching nose, or a launching gantry, are pushed or pushed onto the pier head of a bridge pier, and / or when a structural component is pushed off a bridge pier, significant forces act on the pier. Especially in the construction of new bridges, the pier head is usually free, forming a free end of the pier. The forces applied during the pushing process are distributed along the entire length of the pier and across the pier base opposite the head. As a result of these forces, particularly in the case of tall bridges with correspondingly long piers, considerable spatial deflections of the pier head (i.e., pier head deflections) from its original position can occur. Any remaining pier head deflections after the construction process are undesirable, as they can impair the load-bearing capacity of the bridge.During the construction process, pier head deflection complicates the positioning of the bridge superstructure. Furthermore, pier head deflection is a measure of the forces acting on the bridge pier, with excessive forces potentially damaging the pier. Additionally, excessive pier head deflection can cause the finished bridge to deviate from its predetermined position. For example, an offset between the bridge superstructure and the abutment may occur. Therefore, knowledge of the pier head deflections both during and after the insertion or placement of a structural unit onto the pier heads is desirable. Moreover, even without pier head deflection, the position of the bridge superstructure can deviate from a target position determined during the bridge design phase. This occurs, for instance, when prefabricated segments are inserted onto the bridge piers with incorrect alignment.

[0006] A method is known from CN 109837836 A in which the relative alignment of the bridge superstructure and the pier head is monitored using infrared sensors. However, this method does not allow for unambiguous conclusions about the absolute pier head deflection or the absolute position of the bridge superstructure.

[0007] A method is known from CN 110 823 183 B in which the deflection of the pylon head is determined using a laser and a laser plumb line. The laser is mounted on the pylon head by means of a special construction that ensures that the laser is perpendicular.

[0008] It is therefore an object of the present invention to provide a method and a device for monitoring the deflection of the pier head of a bridge pier and / or the positional deviation of a bridge superstructure, which are in particular particularly accurate, cost-effective, easy to implement and / or reliable.

[0009] In a first aspect, the invention solves the aforementioned problem with a method for monitoring the deflection of a bridge pier head and / or the positional deviation of a bridge superstructure, particularly in the construction and / or dismantling of bridges using incremental launching and / or launching gantry, the method comprising the steps: preferably determining a fixed point; preferably fixing the fixed point in a fixed spatial relation to a pier base of the bridge pier; arranging a plumb laser at the fixed point; perpendicularly projecting a projection point of the fixed point towards a pier head of the bridge pier using a laser beam of the plumb laser; fixing a laser plumb disc in a fixed spatial relation to a pier head of the bridge pier using the projection point;Capturing the position of at least one control characteristic relative to the laser plumb line during and / or after sliding a component onto the pillar head and / or during and / or after sliding a component off the pillar head. The method can therefore be used only during sliding, only during sliding, or during both sliding and sliding.

[0010] The control characteristic is a characteristic suitable for monitoring the pier head deflection and / or the positional deviation of the bridge superstructure. For this purpose, the position of the control characteristic is detected relative to the laser plumb line. For example, and preferably, the projection point of the fixed point can be a control characteristic. A specific feature of the bridge superstructure, such as a measuring point or an edge of the superstructure, can also be such a control characteristic. Preferably, the control characteristic is optically detectable. The position of the control characteristic is detected relative to the laser plumb line. For example, the position of the projection point on the laser plumb line and / or the alignment of a longitudinal edge of the bridge superstructure to the laser plumb line or a marking (in particular, a grid line) on it can be detected.Fixing the laser plumb line can, in principle, be carried out before or simultaneously with determining the fixed point, fixing the fixed point, and positioning the plumb laser, but is preferably performed only during the projection. Furthermore, the projection preferably takes place over a period of time.

[0011] The method according to the invention allows for particularly simple and reliable monitoring of the pier head deflection and / or the positional deviation of a bridge superstructure. For example, and preferably, the fixed point is a survey point that is particularly well suited for monitoring the position of the pier head or a bridge superstructure. By fixing the fixed point in a fixed spatial relationship to a pier base of the bridge pier, the position of the pier is always known. The method can be repeated at intervals. Preferably, the fixed point is fixed on a subsoil at a predefined distance from the pier base. Particularly preferably, the fixed point is marked and fixed on a fixing plate arranged adjacent to the pier base. The fixing plate can preferably be a concrete slab that is protected against movement relative to the pier base by its own weight and / or by other fixing means. Such fixing means can, for example, be ground anchors.Preferably, the fixed point lies outside the vertical projection of the pier head onto the ground. In some variations, the fixed point can be attached to a frame mounted on the pier base foundation. The fixed point is preferably located in the ground area or in the bearing area of ​​the pier base. It should be understood that even a fixed fixed point can be altered in its spatial position relative to the pier base by the application of large forces. However, during normal construction operations, the spatial relationship of the fixed point to the pier base remains constant.

[0012] The plumb laser is designed to emit a vertical laser beam. Positioned at or above the fixed point, the laser beam projects the fixed point vertically upwards, from the base of the pillar to the top. The laser beam projects perpendicularly towards the top of the pillar. Placing the fixed point and the plumb laser at the base of the pillar significantly simplifies the process, as the base is usually more easily accessible than the top. The plumb laser projects the fixed point with high accuracy to or near the top of the pillar, allowing for high precision despite the simplified procedure. The laser plumb disc serves as a target for the laser beam, or a projection surface. It acts as a canvas for the laser beam emitted by the plumb laser. The fixed point is projected onto the laser plumb disc.The laser plumb line is fixed in a fixed spatial relationship to the pier head of the bridge pier. The laser plumb line is fixed using the projection point, so that the laser plumb line can be positioned vertically above the fixed point before being slid on or off. If the pier head deflects, the laser plumb line moves with the pier head, while the fixed point retains its position. Without deflection of the pier head, the projection point of the fixed point lies on a target point of the laser plumb line, which is preferably the center of the laser plumb line.

[0013] In a first preferred embodiment, the projection point of the fixed point is a control characteristic and the laser plumb disc is fixed to the pillar head during fixing in such a way that the control point lies on a target point of the laser plumb disc.

[0014] Preferably, the acquisition of the position of at least one control characteristic comprises acquiring the position of the projection point of the fixed point on the laser plumb line, wherein the method further comprises: determining a positional deviation between the target point and the position of the projection point during and / or after sliding the assembly onto the pier head and / or during; and determining a pier head deflection resulting from the positional deviation. It should be understood that, in addition to the position of the projection point, other control characteristics can also be acquired.

[0015] When the column head is deflected, the laser plumb line shifts, while the position of the projection point of the fixed point remains largely unchanged. Depending on the direction of the column head deflection, the position of the projection point shifts across the laser plumb line (or the laser plumb line shifts relative to the projection point). The projection point therefore moves away from the target point on the laser plumb line. If the position of the projection point of the fixed point on the laser plumb line is recorded during and / or after a component is slid onto / off the column head, a positional deviation between the target point, which is fixed on the laser plumb line, and the projection point can be determined. The column head deflection can then be calculated from this positional deviation. This positional deviation could, for example, represent the column head deflection.Alternatively or additionally, the pier head design can also be determined to a good approximation using simple trigonometric functions, if the length of the bridge pier or its height between the pier head and the pier base is known.

[0016] Preferably, the pier head is free when the laser plumb line is fixed. A free pier head is a free end of the bridge pier that is not in contact with a structural unit, in particular a bridge superstructure, a launching gantry and / or a launching nose.

[0017] In a preferred embodiment, the method comprises the step of determining a target position point of a bridge superstructure encompassed by the structural unit, wherein the fixed point is a vertical projection of the target position point in the direction of the pier base. The target position point marks the intended position of the bridge superstructure relative to the ground as specified in the bridge design. The fixed point, determined as a vertical projection of the target position point in the direction of the pier base or onto the ground, can thus be advantageously used to also determine positional deviations of the bridge superstructure. In simplified terms, the fixed point lies exactly vertically below the target position point of the bridge superstructure. The bridge superstructure can also constitute the structural unit.

[0018] According to a preferred embodiment, the target position point lies on a longitudinal edge of the bridge superstructure (marking the target position of this longitudinal edge). The longitudinal edge is particularly prominent and can be easily recognized even from a distance. Preferably, the bridge superstructure has a box girder profile. The target position point of the bridge superstructure then preferably lies on a longitudinal edge between an outer web and a bottom plate of the box girder profile. Box girder profiles are particularly suitable for bridge construction using the incremental launching method. The longitudinal edge runs essentially parallel to a longitudinal direction of the finished bridge between its abutments. Furthermore, the position of the longitudinal edge between the outer web and the bottom plate of the box girder profile is important for the stability of the bridge. However, the method is also suitable for bridge superstructures without a box girder.

[0019] Preferably, the laser plumb line has a guide point, wherein the laser plumb line is attached to the pier head such that the guide point is essentially congruent with a target position of a longitudinal edge of the bridge superstructure. Preferably, the longitudinal edge of the bridge superstructure is a control characteristic, and detecting the position of at least one control characteristic preferably includes detecting the position of the longitudinal edge relative to the laser plumb line. The guide point is preferably a grid line, in particular a grid line running through the center of a grid on the laser plumb line. The laser plumb line is preferably fixed to the pier head before the structural unit, in particular the bridge superstructure, is slid onto the bridge pier or before the structural unit is slid off the bridge pier. The orientation is preferably selected such that the guide point corresponds exactly to the desired position.The target position of the longitudinal edge of the box girder after being slid onto / off corresponds to the laser plumb line. This allows the laser plumb line to be used to monitor the relative alignment between the pier head and the bridge superstructure. Preferably, the laser plumb line is at least partially transparent. The method preferably further comprises: determining a longitudinal alignment error of the bridge superstructure and pier head if the longitudinal edge of the bridge superstructure deviates from the guideline after the superstructure has been slid onto the pier head and / or after it has been slid off. The deviation can be a parallel displacement and / or an angular deviation. In the case of a parallel displacement, the guideline and the longitudinal edge are parallel and spaced apart. In the case of a purely angular deviation, the guideline and the longitudinal edge intersect at the center of the grid.If the grid alignment deviates from the guideline after the bridge superstructure has been slid into place, the position of the pier head and / or the bridge superstructure does not correspond to the target position specified in the bridge design. Although this is preferred, the laser plumb line does not need to be transparent. The laser plumb line, precisely positioned using the plumb laser, allows for the simple detection of longitudinal alignment errors and the monitoring of positional deviations of the bridge superstructure. The plumb laser and its projection point can then be used, if necessary, solely for positioning the laser plumb line at the pier head. However, the advantage of the method according to the invention is that both pier head deflection and positional deviations of the bridge superstructure can be monitored.

[0020] Preferably, the acquisition of the position of at least one control characteristic, the determination of the positional deviation, the determination of the pier head deflection, and / or the determination of a longitudinal alignment error are performed continuously. For example, a temporal progression of the pier head deflection can also be recorded, allowing for particularly accurate determination of loads on the bridge pier. Furthermore, it enables the fastest possible response to an incipient or unplanned pier head deflection or a longitudinal alignment error of the bridge superstructure. The position of the projection point can be determined during and / or after the launching and / or retraction of a structural unit, in particular a bridge superstructure, a launching nose, and / or a launching gantry. Thus, the positional deviation and / or the pier head deflection can be determined, for example, both during and after the launching process.

[0021] In a preferred embodiment, the method further comprises: reducing the feed rate of a feed unit if the determined column head deflection exceeds a deflection limit. Alternatively or additionally, the method further comprises: reducing the feed rate of a feed unit if the determined longitudinal alignment error exceeds an alignment error limit. Reducing the feed rate can also mean reducing it to zero or switching it off completely. In variants, the feed rate can also be reversed, so that the assembly is then moved in the opposite direction. In response to the detection of an undesired column head deflection and / or an undesired longitudinal alignment error, the feed rate of the assembly can be slowed down, interrupted, or reversed in the method according to the invention.Preferably, the feed rate is automatically reduced if the deflection limit and / or the alignment error limit are exceeded. Preferably, the feed rate is reduced if the pier head deflection in one or more geometric directions exceeds a deflection limit. Exceeding a limit can, in particular, mean exceeding or reaching the limit. Preferably, the alignment error limit and / or the deflection limit are represented by a marking on the laser plumb line. Particularly preferably, the laser plumb line includes a target range and a violation range. Thus, the deflection limit can be exceeded if the projection point of the fixed point is outside the target range and / or the longitudinal edge of the bridge superstructure lies outside the target range.The procedure may preferably also include stopping the feed unit if the determined longitudinal alignment error violates an alignment error limit and / or if the determined column head deflection violates a deflection limit.

[0022] In a preferred embodiment, the method further comprises the step of determining the feed rate, in particular a feed pressure, of the feed unit, wherein the determination of the feed rate preferably occurs simultaneously with the determination of the position of at least one control characteristic. The feed unit is designed to push the construction unit onto the pier head and / or push it off the pier head. In bridge construction using the incremental launching method, the feed unit moves the already manufactured incremental segments and the launching nose, if present, in the longitudinal direction of the bridge. The feed unit is thus designed, among other things, to push the longitudinally foremost construction unit onto the pier head. Preferably, the feed unit is a hydraulic feed unit. A characteristic parameter of the feed rate is a feed pressure, which is provided, for example, by hydraulic cylinders designed to move the bridge superstructure.The feed pressure corresponds to a feed force, which in turn corresponds to head forces applied to the pier head. Furthermore, the feed rate can be, include, or correspond to a feed velocity. Knowledge of the feed rate allows, on the one hand, a more precise determination of the load acting on the pier head and, on the other hand, corrective interventions on the feed unit. Preferably, the method further includes the step of assigning the determined pier head deflection and / or positional deviation to the feed rate, which is preferably recorded simultaneously.

[0023] Preferably, the laser plumb line has a grid. A grid allows for particularly easy determination of the positional deviation. This increases the accuracy of the method. For example, the positional deviation can still be determined with high accuracy even under poor visibility conditions and / or at a large distance from the laser plumb line. Preferably, the grid is a square grid. The grid preferably has a spacing of 1 cm x 1 cm, 0.5 cm x 0.5 cm, 1.5 cm x 1.5 cm, 2 cm x 2 cm, 2.5 cm x 2.5 cm, 3 cm x 3 cm, 4 cm x 4 cm, or 5 cm x 5 cm. The reference point preferably forms the center point of the grid.

[0024] In a preferred embodiment, the position of the at least one control characteristic is detected by at least one camera, preferably a wireless camera. A wireless camera allows for particularly easy transmission of images or video recordings (or corresponding image or video data). The arrangement of plumb laser, laser plumb disc, and camera enables cost-effective and robust detection of the control characteristic's position. Furthermore, high accuracy can be achieved, especially when using a grid on the laser plumb disc. Using a wireless camera facilitates the transmission of images or videos. Additionally, the use of cameras allows for the simultaneous monitoring of the pier head deflections of multiple bridge piers with minimal effort.

[0025] Preferably, the method further comprises: providing the recorded position of the control characteristic, the determined positional deviation, the determined pier head deflection, and / or the determined longitudinal alignment error for remote access, in particular by providing it on a server. It should be understood that providing the recorded position of the projection point of the fixed point on the laser plumb line, the position of the longitudinal edge of the bridge superstructure in relation to the laser plumb line, the determined positional deviation, the determined pier head deflection, and / or the determined longitudinal alignment error can, in particular, be the provision of corresponding data. For example, and preferably, providing the recorded position of the projection point of the fixed point on the laser plumb line is done by providing images and / or videos or image data and / or video data.For example, the wireless camera can capture the position of the projection point of the fixed point on the laser plumb line, and corresponding image data can then be transmitted directly or via a central unit to a server. The server is preferably a web server. Providing the data on a web server enables access to the captured position of the projection point, the positional deviation, and / or the laser plumb line via an internet connection.

[0026] Preferably, at least one recorded feed rate is also made available for remote access. For example, both the feed rate and the pier head deflection can be monitored from a control station. If the pier head deflection exceeds a limit value and / or a longitudinal alignment error is detected, the feed rate can be reduced by appropriately controlling the feed unit to counteract the pier head deflection and / or the longitudinal alignment error. The control station can be connected to the server. For example, the control station can be located in an office building remote from the bridge construction site, and monitoring and / or control can be performed via the internet.

[0027] The procedure is preferably carried out for multiple bridge piers. Therefore, several fixed points, plumb lasers, etc., can be used. The pier head deflection and / or the positional deviation of the bridge superstructure is then monitored separately for each bridge pier using a laser plumb disc and a plumb laser fixed to an associated fixed point. The procedure can be carried out for multiple bridge piers simultaneously and / or sequentially.

[0028] In a second aspect, the invention solves the aforementioned problem with a device for monitoring the deflection of the pier head of a bridge pier and / or the positional deviation of a bridge superstructure, particularly in the construction and / or dismantling of bridges using the incremental launching method and / or by means of a launching gantry, the device comprising: a plumb laser designed to be arranged adjacent to and in a fixed spatial relationship to a pier base of the bridge pier and to emit a vertical laser beam; a laser plumb disc, preferably having a measuring grid; a plumb disc fixing designed to fix the laser plumb disc horizontally projecting from a pier head of the bridge pier onto the pier head and above the plumb laser, so that the laser beam of the plumb laser can be projected onto the laser plumb disc;and a camera unit for capturing images and / or videos of the laser beam striking the laser plumb line. The camera unit can be configured, in particular, for capturing image data and / or video data. The camera unit can therefore be or comprise a digital camera. The device is particularly preferably configured for continuously monitoring the pillar head deflection. The device can be configured, in particular, for carrying out the method according to the first aspect of the invention.

[0029] In a first preferred embodiment, the device includes a central unit configured for displaying, recording, and / or evaluating an image and / or video from the camera unit. The central unit can, for example, comprise a control computer for the device and / or a server. Preferably, the central unit is configured to determine a pillar head deflection and / or a positional deviation between a target point on the laser plumb line and a projection point of the laser beam from the images and / or videos captured by the camera unit. For example, the central unit can be configured to determine the position of the projection point and the target point from image data of the camera unit and to calculate the positional deviation from this.Furthermore, the central unit can be configured to determine load parameters on the bridge pier using predefined values, which include in particular geometric dimensions of the bridge pier, and the positional deviation. Alternatively or additionally, the central unit can be configured to determine a longitudinal alignment error of the bridge superstructure and pier head using the detected position of a longitudinal edge of a bridge superstructure relative to the laser plumb line.

[0030] In a preferred embodiment, the camera unit comprises at least one wireless camera, and the central unit includes a wireless receiver configured for communication with the wireless camera. Using a wireless camera and receiver significantly simplifies the setup of the device on a construction site. For example, no cables need to be laid from a camera unit mounted on a pier head to a central unit located at a control station. Furthermore, the deflections of several pier heads of different bridge piers can be monitored simultaneously with particular ease. The device therefore preferably includes several camera units, laser plumb lines, and plumb line fixings. However, for monitoring multiple pier head deflections, it may also be sufficient to use only one central unit.Instead of a wireless camera, preferably at least one wired camera may be provided, equipped with a transmitter for wirelessly transmitting camera data (image or video data). The wireless receiver may, for example, be a receiver connected to a control computer. Preferably, the wireless camera and the wireless receiver are configured for communication via Bluetooth and / or one of the mobile communication standards GPRS, EDGE (2G), UMTS (3G), LTE (4G), or 5G.

[0031] Preferably, the device further comprises a feed detection unit configured to acquire feed information representing at least one feed rate of a feed unit. The feed detection unit is, or preferably includes, a pressure detection unit configured to acquire pressure information representing the feed pressure of a feed unit. The pressure information can, for example, be measured values ​​or signals from a pressure sensor. The feed detection unit is, or preferably includes, a camera. The pressure information is then preferably image or video data showing a pressure reading of the feed unit. For example, a camera can be provided that captures a video image of a pressure gauge of the feed unit and then transmits this video image to the central processing unit for further processing.Preferably, the central unit is configured to assign a timestamp to the feed information and / or the images and / or videos of the laser beam striking the laser plumb line. Preferably, the central unit can also assign a timestamp to a measured positional deviation and / or a column head deflection. Assigning a timestamp facilitates subsequent data evaluation and / or enables the correlation of feed information and images. Preferably, the central unit is configured to control, particularly preferably remotely, the feed unit and / or a component of the feed unit. The central unit can be configured to control the feed pressure of at least one hydraulic cylinder, particularly preferably all hydraulic cylinders, of the feed system.Preferably, the central unit is configured to determine whether a detected longitudinal alignment error violates an alignment error limit, and / or whether a detected column head deflection violates a deflection limit. Particularly preferably, the central unit is configured to stop the feed unit if the longitudinal alignment error violates the alignment error limit and / or if the column head deflection violates the deflection limit.

[0032] In a preferred embodiment, the central unit is designed to allow remote access and / or to provide data on a web server. In particular, the central unit is internet-enabled. The central unit can also be a server, especially a web server, or include such a server. Images and / or videos recorded or analyzed by the central unit can thus be accessed even from a great distance. This enables rapid evaluation by experts and allows for short-term adjustments to the bridge construction process.

[0033] Preferably, the device further comprises a laser fixing. The laser fixing is provided for the stationary fixation of the laser. Preferably, the laser fixing includes a fixing screw for fixing the plumb laser. The plumb laser can have a corresponding fixing thread that is screwed onto the fixing screw. The fixing screw preferably has an alignment bore, which particularly preferably extends along a longitudinal axis of the fixing screw through the fixing screw. The alignment bore is provided for centering the laser fixing over a target point. This allows the target point to be determined and marked at the start of construction using conventional surveying instruments. The alignment bore is particularly preferably a through bore. In this case, the alignment bore allows a clear view of the target point, so that the fixing screw can be positioned exactly centered over the previously determined target point.However, it is also possible that the alignment hole is a blind hole designed to accommodate a target point marker. For example, the target point marker could be a pin onto which the alignment hole is placed.

[0034] In a third aspect, the invention solves the aforementioned problem with a launching system for the construction and / or dismantling of bridges, particularly using incremental launching and / or launching gantry systems. The launching system comprises a launching unit for moving a construction unit and a device according to the second aspect of the invention. The construction unit is or preferably comprises a bridge superstructure, a launching nose, and / or a launching gantry. The device is preferably configured to switch off the launching unit and / or to stop the launching of the launching unit. For example, the central control unit for the launching unit can be provided. However, it can also be provided that the device according to the second aspect of the invention has a launching control system separate from the central control unit.Preferably, the device is designed to switch off the feed unit and / or stop the feed of the feed unit in response to the detection of a pillar head deflection that violates a deflection limit, in response to the detection of a position deviation that violates a position deviation limit, and / or in response to the detection of a longitudinal alignment error that violates an alignment error limit.

[0035] It should be understood that the method according to the first aspect of the invention, the apparatus according to the second aspect of the invention, and the feed system according to the third aspect of the invention may have the same and similar sub-aspects, as set forth in particular in the dependent claims to the method according to the first aspect of the invention. Therefore, for the apparatus and the feed system, full reference is made to the preceding descriptions of the method according to the first aspect of the invention.

[0036] Embodiments of the invention are now described below with reference to the drawings. These drawings are not necessarily intended to represent the embodiments to scale; rather, where this is helpful for clarification, the drawings are presented in a schematic and / or slightly distorted form. With regard to additions to the teachings directly apparent from the drawings, reference is made to the relevant prior art. It should be noted that numerous modifications and changes concerning the form and detail of an embodiment can be made without deviating from the general idea of ​​the invention. The features of the invention disclosed in the description, the drawings, and the claims can be essential for the further development of the invention, both individually and in any combination.Furthermore, the invention encompasses all combinations of at least two of the features disclosed in the description, the drawings, and / or the claims. The general idea of ​​the invention is not limited to the exact shape or detail of the preferred embodiments shown and described below, nor is it limited to an object that would be restricted compared to the object claimed in the claims. Where specified dimensioning ranges are given, values ​​lying within the stated limits are also disclosed as limit values ​​and may be used and claimed as desired. For the sake of simplicity, identical or similar parts, or parts with identical or similar functions, are used below as reference numerals.

[0037] Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawings; these show in: Fig. 1 a schematic representation of the construction of a bridge using the incremental launching method, wherein a launching nose has not yet been pushed onto a bridge pier and wherein a device for monitoring a pier head deflection of a pier head of the bridge pier is provided; Fig. 2 a schematic representation of a grid of a laser plumb line with the projection point of a laser beam projected onto the grid before the launching nose is pushed onto the pier head, wherein the projection point is coincident with a target point; Fig. 3 a to Fig. 1 analogous schematic representation, wherein the projection nose is pushed onto the pier head and the pier head of the bridge pier is deflected; Fig. 4 a to Fig. 3 An analogous schematic representation of the grid after the launching nose has been pushed onto the pier head, wherein the projection point is shifted by a positional deviation relative to the target point; Fig. 5 a cross-section of a bridge superstructure with a hollow box profile, wherein the bridge superstructure is arranged in a target position on the pier head of a bridge pier; Fig. 6 a schematic representation of a second embodiment of a grid of a laser plumb line; and in Fig. 7 a block diagram illustrating the sequence of a method for monitoring the pier head deflection of a bridge pier.

[0038] Fig. 1 Figure 1 schematically shows a bridge construction site 200 where a bridge 202 is being constructed using the incremental launching method on a foundation 204. The bridge 202 comprises a bridge superstructure 206, a bridge pier 208, and a first abutment 210. Behind the abutment 210, a fabrication facility 212 is provided, in which incremental segments 214 of the bridge superstructure 206 are manufactured. After completion of an incremental segment 214, the already constructed bridge superstructure 206, or its incremental segments 214, is moved in the launching direction R1, which here corresponds to a longitudinal direction of the completed bridge 202, and another incremental segment 214 is joined to the already constructed bridge superstructure 206. To reduce the cantilevered length of the bridge superstructure 206, a launching nose 216 is attached in the launching direction R1 in front of a first incremental segment 214.1.

[0039] During the sliding process, the bridge superstructure 206 is pushed onto a pier head 218 of the already completed bridge pier 208, a process also known as launching. In this process, the launching nose 216 first comes into contact with the pier head 218, or is first pushed onto the pier head 218. Fig. 1 The projecting nose 216 is still horizontally spaced from the pier head 218. The bridge pier 208 extends straight upwards from a pier base 220, which is connected to a foundation 222 located in the ground 204. In the Fig. 1 In the illustrated construction phase, the pier head 218 of the bridge pier 208 is arranged vertically above the pier base 220.

[0040] A fixed point 3 is located next to the pier base 220 on the subgrade 204 and is fixed there by means of a concrete slab 5. The fixed point 3 can, for example, be a pin screwed into the concrete slab 5. The weight of the concrete slab 5 prevents the fixed point 3 from shifting. The fixed point 3 is therefore fixed in its spatial relation to the pier base 200. Preferably, the fixed point 3 can also be fixed to the foundation 222 of the bridge pier 208.

[0041] A plumb laser 7 of a device 1 for monitoring a pillar head deflection 9 of the pillar head 218 is arranged at the fixed point 3. The plumb laser 7 emits a laser beam 11 vertically upwards. There, the laser beam 11 strikes a laser plumb disk 13, which is arranged in a fixed spatial relationship to the pillar head 218. The laser plumb disk 13 is fixed to the pillar head 218 by means of a plumb disk fixing 15, which here is designed as a rail system 25. The laser beam 11 of the plumb laser 7 thus projects the fixed point 3 onto the laser plumb disk 13. A projection point 17 of the fixed point 3 is visible on the laser plumb disk 13.

[0042] The device 1 for monitoring the pier head deflection 9 further comprises a camera unit 19, which here includes a first wireless camera 21. The camera 21 is fixed to the pier head 218 of the bridge pier 208 in such a way that it can capture videos of the laser beam 11 striking the laser plumb line 13 or of the projection point 17 of the fixed point 3 on the laser plumb line 13. The wireless camera 21 is a digital camera that wirelessly transmits the captured video data to a central unit 23 of the device 1. Here, the central unit 23 is a network-enabled, in particular internet-enabled, control computer 27. The control computer 27 stores the video data transmitted by the wireless camera 21. Furthermore, the control computer 27 allows remote access to the stored video data via the internet. In the illustrated embodiment, the control computer 27 also serves as a network server.

[0043] In Fig. 1 The pier head 218 of the bridge pier 208 is free and not in contact with the launching nose 216, which forms a structural unit 224. The bridge pier 208 is not deformed, and the pier head 218 lies vertically above the pier base 220. Fig. 1 There is no pillar head deflection 9 yet, or it has a value of 0. The laser plumb line 13 is fixed to the free pillar head 218 such that the projection point 17 of the fixed point 3 lies on a target point 29 of the laser plumb line 13. In this embodiment, the target point 29 is a center 31 of a grid 33 of the laser plumb line 13 (see figure). Fig. 2 ). Grid 33 here is a square grid with a grid spacing of 35, measuring 1 cm x 1 cm.

[0044] The wireless camera 21 transmits the in Fig. 2 Illustrated image of grid 33 and projection point 17 to the central unit 23. This determines for the in Fig. 2 The image shown, in which the projection point 17 lies on or coincides with the target point 29, indicates that there is no pillar head deflection 9.

[0045] In the next step of the bridge construction, the bridge superstructure 206 is now being inserted in the insertion direction R1. For this purpose, a insertion unit 226 is provided at the first abutment 210. The insertion unit 226 comprises a hydraulic cylinder 228 which is coupled to the bridge superstructure 206 in order to move it in the insertion direction R1. For this purpose, the hydraulic cylinder 228 of the insertion unit 226 is subjected to a insertion pressure pV. The insertion pressure pV constitutes a insertion quantity 37 of the insertion unit 226. The device 1 and the insertion unit 226 are part of a insertion system 150.

[0046] Fig. 3 shows a to Fig. 1 Analog view of bridge construction site 200, where the launching nose 216 is now pushed onto the pier head 218 of bridge pier 208. The pier head 218 is in Fig. 3 no longer free, but is in contact with the construction unit 224, which here is formed by the launching nose 216. In other embodiments, however, the first indexing segment 214.1 can, for example, be arranged at the front and form the construction unit 224. When the launching nose 216 is pushed onto the pier head 218, the launching nose 216 rubs against the pier head 218 and thus transmits part of a launching force applied by the launching unit 226 to the bridge superstructure 206 to the pier head 218. The resulting head force F is in Fig. 3 indicated by an arrow.

[0047] The bridge pier 208 is supported only at the pier base 220 opposite the pier head 218 on the subsoil 204 and, in simplified terms, acts as a bending beam. The head force F applied by the structural unit 224 to the pier head 218 causes a bending of the bridge pier 208, resulting in a deflection 9 of the pier head 218. Fig. 3 The pillar head 218 is displaced to the left by the pillar head deflection 9. The pillar head deflection 9 is in Fig. 3 Illustrated. The laser plumb line 13, fixed in a fixed spatial relationship to the pier head 218, is also displaced horizontally by the pier head deflection 9 when the bridge pier is deformed.

[0048] The position of the fixed point 3 and the plumb laser 7 mounted on it does not change when the bridge superstructure 206 is inserted or when the launching nose 216 is pushed onto the pier head 218. Therefore, the absolute position of the projection point 17 also remains unchanged. However, since the laser plumb disk 13 is essentially displaced horizontally, the projection point 17 moves on the laser plumb disk 13. The projection point 17 thus moves out of the center 31 of the grid 33 and is no longer coincident with the target point 29.

[0049] Fig. 4 This shows the positional deviation 39 between the target point 29 located at the center 31 of the grid 33 and the projection point 17 after the assembly unit 224 has been slid into place. In the illustrated embodiment, sliding the extension nose 216 onto the column head 218 results in a positional deviation 39 of 3 cm in the feed direction R1. The projection point 17 of the fixed point 3 is therefore a control characteristic 18 suitable for monitoring the column head deflection 9. The position of this control characteristic 18 is detected by the camera 21 in relation to the laser plumb line 13.

[0050] The wireless camera 21 transmits to the in Fig. 4 The central unit 23 receives image data corresponding to the illustrated image. The central unit 23 evaluates this image data and determines the column head deflection 9 from the positional deviation 39. Alternatively, the central unit 23 can display the image data on a screen, allowing a user to determine the positional deviation 39 and / or the column head deflection 9 from the displayed images. In this configuration, the central unit 23 is designed to provide a warning signal if the column head deflection 9 and / or the positional deviation 39 exceeds a relevant limit value. For example, the central unit 23 can emit a warning tone if the positional deviation 39 reaches a value of 4 cm or greater. The warning signal can also be a stop signal provided by the central unit 23 to the feed unit 226. An automatic shutdown function can thus be implemented using the device 1.

[0051] In the Figuren 1 bis 4 In the illustrated example, the pier head 318 of the bridge pier 308 is deflected in the feed direction R1. The bridge superstructure 306 is moved essentially uniformly in the feed direction R1. However, feed units 226 typically have several hydraulic cylinders 228 that act on sections of the bridge superstructure 206 offset transversely to the feed direction R1. Thus, longitudinal alignment errors can occur when the bridge superstructure 206 is being inserted. For example, the bridge superstructure 206 can become misaligned in the feed direction R1 if different feed pressures pV are applied to the hydraulic cylinders 228. The device 1 is also designed to determine such longitudinal alignment errors 41. It should be understood that the determination of longitudinal alignment errors 41 can be carried out independently of determining a pier head deflection 9.

[0052] Fig. 5 Figure 1 shows a cross-section of a bridge superstructure 206 which is pushed onto the pier head 218 of bridge pier 208 in a target position 240. In the target position 240, the bridge superstructure 206 is positioned exactly centrally on the pier head 218 in the transverse direction R2. The transverse direction R2 is perpendicular to the launching direction R1. Therefore, in the target position 240, there is no longitudinal alignment error 41 of the bridge superstructure 206.

[0053] In the Fig. 5 In the illustrated cross-section, the bridge superstructure 206 has a box girder profile 230. The box girder profile 230 of the bridge superstructure 206 comprises a base plate 232, two outer webs 234, and a deck plate 236. The outer webs 234 connect the base plate 232 to the deck plate 236. At a transition between the base plate 232 and the outer web 234, the box girder profile 230 has a longitudinal edge 238. The position of this longitudinal edge 238 is particularly suitable for determining the position of the bridge superstructure 206. The longitudinal edge 238 is thus a control characteristic 18 for monitoring a positional deviation 39 of the bridge superstructure 206. Preferably, when determining the fixed point 3, a target position 43 of the longitudinal edge 238 of the bridge superstructure 206 is determined. This target position 43 corresponds to the planned position of the longitudinal edge 238 after completion of bridge 202. The target position 43 is therefore preferably determined during the planning phase of bridge 202.The fixed point 3 is preferably a projection of a point of the longitudinal edge 238 located in the target position 43 onto the subsoil 204. The fixed point 3 is therefore preferably determined or defined exactly below the target position 43 of the longitudinal edge 238.

[0054] Fig. 6 Figure 1 shows a second preferred embodiment of the grid 33 of the laser solder disk 13. The grid 33 according to the second embodiment is essentially identical to the grid 33 according to the first embodiment. Fig. 2 and Fig. 4 The embodiment shown is an example. Here, however, the grid 33 additionally has a guideline 45. Preferably, the guideline 45 runs through the center 31 of the grid 33. The laser plumb line 13 is preferably attached to the free pier head 318 such that the guideline 45 is exactly congruent with the target position 43 determined during the planning of the bridge 202. Here, the laser plumb line 13 is at least partially transparent, so that the position of the longitudinal edge 238 is visible through the laser plumb line 13.

[0055] If the bridge superstructure 206 is pushed onto the pier head 218 of the bridge pier 208 as planned, then the longitudinal edge 238 of the box girder 230 should lie exactly on guideline 45. If the bridge superstructure 206 is not pushed in according to plan in the launching direction R1, a longitudinal alignment error 41 occurs. The bridge superstructure 206, and thus also its longitudinal edge 238, is then tilted, for example, in relation to the planned launching direction R1. Consequently, after the bridge superstructure 206 has been pushed in, the longitudinal edge 238 is not congruent with guideline 45. This case is described in Fig. 6 The longitudinal edge 238 forms an angle with guideline 45 and is also shifted transversely to guideline 45. The angular deviation and the simultaneous parallel shift of the longitudinal edge 238 from guideline 45 indicate a longitudinal alignment error 41 of the bridge superstructure relative to the pier head 218.

[0056] Camera unit 19 captures a Fig. 6 The system captures the corresponding image and sends the corresponding image data to the central unit 23. The images can then be displayed on the central unit 23 or on a screen of the central unit 23. This allows an operator to determine whether a longitudinal alignment error 41 is present. Alternatively, the central unit 23 can automatically evaluate the images or image data and determine a longitudinal alignment error 41 if the position of the longitudinal edge 238 deviates from the guideline 45 by more than a predetermined limit value.

[0057] The device 1 thus enables, for example, an operator of the feed unit 226 to detect a longitudinal alignment error 41 of the bridge superstructure 206 that occurs during the insertion of the bridge superstructure 206 and then reduce the feed pressure pV supplied to the hydraulic cylinders 228 of the feed unit 226 to zero in order to stop the insertion of the bridge superstructure 206. It can also be provided that the central unit 23 is configured to control the feed unit 226. In particular, the central unit 23 can be configured to automatically control the feed unit 226. For example, the central unit 23 can then automatically detect a longitudinal alignment error 41 and / or a pier head deflection 9 using the image data from the camera unit 19.If the longitudinal alignment error 41 and / or the pier head deflection 9 exceed a corresponding predefined limit value, the feed unit 226 can reduce the feed pressures pV of the feed unit 226 to stop the feed of the bridge superstructure 206.

[0058] The feed unit 226 also includes a feed rate indicator 240, which is located in the Fig. 1 and 3In the illustrated embodiment, a pressure gauge 242 is used. The pressure gauge 242 displays the feed pressure pV provided at the hydraulic cylinder 228, which here forms a feed quantity 37 of the feed unit 226. The device 1 further comprises a feed detection unit 49. The feed detection unit 49 has a second camera unit 47, which also includes a wireless camera 21. The wireless camera 21 of the second camera unit 47 is also a digital camera that sends image data corresponding to the captured image to the central unit 23. Thus, not only an image of the projection point 17 on the laser plummet 13, but also an image of the pressure gauge 242 can be displayed on a screen of the central unit 23. The device 1 thus allows simultaneous determination of the feed rate 37 and the positional deviation and / or the longitudinal alignment error 41 and / or the column head deflection 9. The central unit 23 is further designed to comply with the illustrations orThe image data from the wireless cameras 21 of the first camera unit 21 and the second camera unit 47 are each assigned a timestamp, or a timestamp contained in the image data is captured. This enables a subsequent assignment of the feed rate 37 to the captured positional deviation 39.

[0059] In other embodiments, the feed unit 226 can also include a pressure sensor that provides pressure signals corresponding to the feed pressure pV. The pressure signals and / or measured values ​​derived therefrom can then be transmitted to the central unit 23 via wired or wireless connections.

[0060] Fig. 7 Figure 1 shows a block diagram illustrating the process of a method 100 for monitoring the pier head deflection 9 of a bridge pier 208. The method 100 is explained below with reference to the device 1 and the bridge 202. In a first step 102 of the method 100, the fixed point 3, or rather its position, is determined. As explained above, the fixed point 3 can be determined as the projection of a point on the longitudinal edge 238 of the bridge superstructure 206 in its intended position 43 onto the subsoil 204. In a subsequent second step 104, the fixed point 3 is fixed on the subsoil 204 in a fixed spatial relationship to the pier base 220. Then, in a third step 106, the plumb laser 7 is positioned on the fixed point 3, and the fixed point is projected vertically upwards by means of the laser beam 11 of the plumb laser 7 (fourth step 108).In a fifth step 110, which here follows the fourth step 108, but can also be performed before steps 102 to 108, the laser plumb line 13 is fixed in a fixed spatial relationship to the pier head 218 of the bridge pier 208. Performing the fifth step 110 after the fourth step 108 facilitates fixing the laser plumb line 13 in a position where the projection point 17 of the fixed point 3 lies on the target point 29 of the laser plumb line 13. Fixing 110 of the laser plumb line 13 can then be carried out using the projection point 17. This significantly simplifies the fixing process. Steps 102 to 110 can also be described as preparatory steps, which are preferably performed before inserting a component 224.

[0061] Following steps 102 to 110, the feed nose 216 can be pushed onto the pillar head 218. In the present embodiment of method 110, in a sixth step 112 of method 100, the position of the projection point 17 on the laser plumb disk 13 is detected during the pushing of the feed nose 216. In the illustrated embodiment, this is the detection 112 of the position of at least one control characteristic 18 in relation to the laser plumb disk 13. From the detected position of the projection point 17 on the laser plumb disk 13, a positional deviation 39 between the target point 29 and the projection point 17 of the fixed point 3 can be determined in a subsequent seventh step 114.

[0062] Following the seventh step 114, an eighth step 116 determines the column head deflection 9 of the column head 318 from the determined positional deviation 39. It should be understood that the positional deviation 39 can also directly constitute the column head deflection 9. Therefore, in the eighth step 116, only the positional deviation 39 can be determined as the column head deflection 9 or equated with it.

[0063] In the present embodiment of method 100, in parallel with the detection of the position of the projection point 17 on the laser plumb disc 13 (sixth step 112), a feed quantity 37 of the feed unit 226 is detected in a ninth step 118. Here, the feed quantity 37 is the feed pressure pV at the hydraulic cylinder 228, which is detected by the second camera unit 47.

[0064] In the present embodiment of method 100, in the sixth step 112, the position of the longitudinal edge 238 of the bridge superstructure 206 in relation to the laser plumb line 13 is simultaneously recorded as a further control characteristic 18, along with the position of the projection point 17 on the laser plumb line 13. From the position of the longitudinal edge 238 in relation to the laser plumb line, a longitudinal alignment error 41 of the bridge superstructure 206 is determined in a tenth step 120 of method 100.

[0065] In an eleventh step 122 of procedure 100, the determined pier head deflection 9 is compared with a deflection limit value G1. Furthermore, in this eleventh step, the determined longitudinal alignment error 41 is compared with an alignment error limit value G2. If the pier head deflection 9 exceeds the deflection limit value G1 and / or if the longitudinal alignment error 41 exceeds the alignment error limit value G2, the feed rate 37 is reduced in a twelfth step 124 of procedure 100 (step: Reduce 124) to stop the feed rate of the bridge superstructure 206. For example, the feed pressure pV can be reduced to zero to stop the feed rate. Bezugszeichenliste:

[0066] 1 Device for monitoring a pier head deflection Fixed point 3 5 Concrete slab 7 Plumb laser 9 Pier head deflection 11 Laser beam 13 Laser plumb disc 15 Plumb disc fixation 17 Projection point of the fixed point on the laser plumb disc 18 Control characteristic 19 Camera unit 21 Wireless camera 23 Central unit 25 Rail system 27 Control computer 29 Target point 31 Center 33 Grid 35 Grid pattern 37 Feed rate 39 Positional deviation 41 Longitudinal alignment error 43 Target position of a longitudinal edge of a bridge superstructure 45 Guideline 47 Second camera unit 49 Feed detection unit 100 Procedure 102 First step of the procedure or determining a fixed point 104 Second step of the procedure or fixing the fixed point 106 Third step of the procedure or positioning a plumb laser on the Fixed point 108 fourth step of the procedure or projecting the fixed point 110 fifth step of the procedure or fixing a laser plumb disc on the pillar head 112 sixth step of the procedure orDetermining the position of at least one control characteristic in relation to the laser plumb line 114 seventh step of the procedure or determining a positional deviation 116 eighth step of the procedure or determining a pier head deflection 118 ninth step of the procedure or determining a feed rate 120 tenth step of the procedure or determining a longitudinal alignment error of the bridge superstructure 122 eleventh step or comparing the pier head deflection with a deflection limit value and / or comparing the longitudinal alignment error with an alignment error limit value 124 twelfth step of the procedure or reducing the feed rate 150 Feed system 200 Bridge construction site 202 Bridge 204 Subsoil 206 Bridge superstructure 208 Bridge pier 210 Abutment 212 Production plant 214 Cycle segments 214.1. First stroke segment 216. Leading nose 218. Pier head 220. Pier base 222. Bridge pier foundation 224. Construction unit 226. Feed unit 228. Hydraulic cylinder 230. Hollow box section 232. Base plate 234. Outer web 236. Cover plate 238. Longitudinal edge 240. Target position F. Head force G1. Deflection limit of pier head deflection G2. Alignment error limit of longitudinal alignment error pV. Feed pressure R1. Feed direction R2. Transverse direction.

Claims

1. A method (100) for monitoring the pillar head deflection (9) of a bridge pillar (208) and / or the positional deviation (39) of a bridge superstructure (206), in particular in the construction and / or dismantling of bridges (202) in the incremental launching method and / or by means of movable scaffolding, the method (100) having the steps: - determining (102) a fixed point (3); - fixing (104) the fixed point (3) in a fixed spatial relation to a pillar foot (220) of the bridge pillar (208); - arranging (106) a plumb laser (7) at the fixed point (3); - plumb line projecting (108) a projection point (17) of the fixed point (3) in the direction of a pillar head (218) of the bridge pillar (208) using a laser beam (11) of the plumb laser (7); - fixing (110) a laser plumb disc (13) in a fixed spatial relation to a pillar head (218) of the bridge pillar (208) using the projection point (17); - detecting (112) a position of at least one control characteristic (18) in relation to the laser plumb disc (13) during and / or after pushing a construction unit (224) onto the pillar head (218) and / or during and / or after pushing a construction unit (224) away from the pillar head (218).

2. The method (100) according to claim 1, wherein the projection point (17) of the fixed point (3) is a control characteristic (18) and wherein the laser plumb disc (13) is fixed to the pillar head (218) during fixing (110) such that the projection point (17) lies on a target point (29) of the laser plumb disc (13).

3. The method (100) according to claim 2, wherein detecting a position of at least one control characteristic (18) includes detecting a position of the projection point (17) of the fixed point (3) on the laser plumb disc (13) and wherein the method (100) further comprises: - determining (114) a positional deviation (39) between the target point (29) and the position of the projection point (17) during and / or after pushing the construction unit (224) onto the pillar head (218) and / or during and / or after pushing the construction unit (224) away from the pillar head (218); and - determining (116) a pillar head deflection (9) of the pillar head (218) from the positional deviation (39).

4. The method (100) according to any of the preceding claims 1 to 3, further comprising the step of: - determining a position target point of a bridge superstructure (206) comprised by the construction unit (224), wherein the fixed point (3) is a plumb line projection of the position target point in the direction of the pillar foot (220).

5. The method (100) according to claim 4, wherein the laser plumb disc (13) comprises a guideline (45), wherein the laser plumb disc (13) is fastened to the pillar head (218) such that the guideline (45) is substantially congruent with a target position (43) of a longitudinal edge (238) of the bridge superstructure (206), wherein the longitudinal edge (238) of the bridge superstructure (206) is a control characteristic (18) and detecting a position of at least one control characteristic (18) comprises detecting the position of the longitudinal edge (238) in relation to the laser plumb disc (13), and wherein the method (100) preferably comprises: - determining a longitudinal alignment error (41) of bridge superstructure (206) and pillar head (218) if the longitudinal edge (238) of the bridge superstructure (206) deviates from the guideline (45) after and / or during pushing onto and / or after and / or during pushing away the bridge superstructure (206).

6. The method (100) according to claim 3 or 5, further comprising the steps of: - reducing (124) a feed variable (37) of a feed unit (226) for moving the construction unit (224) if the determined pillar head deflection (9) violates a deflection limit value (G1) and / or if the determined longitudinal alignment error (41) violates an alignment error limit value (G2).

7. The method (100) according to claim 6, further comprising the step of: - detecting (118) the feed variable (37), in particular a feed pressure (pV), of the feed unit (226), wherein determining the feed variable (37) occurs simultaneously with detecting the position of at least one control characteristic (18).

8. The method according to any of claims 1 to 7, wherein detecting the position of the control characteristic (18) occurs by at least one camera (21), wherein the camera (21) is preferably a wireless camera (21).

9. The method according to any of claims 1 to 8, further comprising the step of: - providing the detected position of the control characteristic (18), the determined positional deviation (39), the determined pillar head deflection (9) and / or the determined longitudinal alignment error (41) for remote access, in particular providing on a web server.

10. A device (1) for monitoring the pillar head deflection (9) of a bridge pillar (208) and / or the positional deviation (39) of a bridge superstructure (206), in particular in the construction and / or dismantling of bridges (202) in the incremental launching method and / or by means of movable scaffolding, the device (1) having a plumb laser (7) configured to be arranged adjacent to and in a fixed spatial relation to a pillar foot (220) of the bridge pillar (208) and to emit a plumb line laser beam (11); a laser plumb disc (13), preferably comprising a measuring grid (33); a plumb disc fixing (15) configured to fix the laser plumb disc (13) projecting horizontally from a pillar head (218) of the bridge pillar (208) at the pillar head (218) and above the plumb laser (7), so that the laser beam (11) of the plumb laser (7) can be projected onto the laser plumb disc (13); and a camera unit (19) for capturing images and / or videos of the laser beam (11) impinging on the laser plumb disc (13).

11. The device (1) according to claim 10, further comprising a central unit (23), which is configured to display, record and / or evaluate an image and / or video of the camera unit (19), wherein the central unit (23) is preferably configured to allow remote access and / or to provide data on a server.

12. The device (1) according to claim 11, wherein the camera unit (19) comprises at least one wireless camera (21) and wherein the central unit (23) comprises a wireless receiving unit, which is configured to communicate with the wireless camera (21).

13. The device (1) according to any of claims 10 to 12, further comprising a feed detection unit (49), which is configured to detect feed information representing at least one feed variable (37) of a feed unit (226), wherein the feed detection unit (49) is preferably or comprises a camera (21).

14. The device (1) according to any of claims 10 to 13, further comprising a laser fixing, which preferably comprises a fixing screw for fixing the plumb laser (7), wherein the fixing screw comprises an alignment bore for centering the laser fixing above a desired position point.

15. A feed system (150) for the construction and / or dismantling of bridges (202), in particular in the incremental launching method and / or by means of movable scaffolding, the feed system (150) comprising a feed unit (226) for moving a construction unit (224), in particular a bridge superstructure (206) or a movable scaffolding, and a device (1) according to any of claims 10 to 14, wherein the device (1) is configured to switch off the feed unit (226), in particular in response to determining a pillar head deflection (9) which violates a deflection limit value (G1), a positional deviation which violates a positional deviation limit value, and / or a longitudinal alignment error (41) which violates an alignment error limit value (G2).

Images