Bridge producing process and monitoring method

Abstract

This bridge producing process leading up to the point where a bridge is constructed includes: a design step (step S11); steps (steps S12-S15) for producing a plurality of members on the basis of a design drawing prepared in the design step; a temporary assembly step (step S17) for actually assembling, in a factory, the plurality of prepared members into the completed form or a partial form of a bridge girder, and then inspecting the shape, size, etc. of the members; a transportation step (step S19) for separating the plurality of assembled members and conveying the same to a construction site; and a site construction step (step S20) for constructing the bridge at the construction site. In some steps from among the plurality of steps (steps S11-S20), inclination information pertaining to a structure including the bridge girder to be used in the process for producing the bridge is measured at a prescribed measurement point by using a sensor, and the result of said measurement is used.

Description

Bridge construction process and monitoring methods

[0001] The present invention relates to a bridge construction process and a monitoring method, and more particularly to a bridge construction process up to the time of erection of a bridge, and a monitoring method for monitoring changes in the shape of a bridge girder.This application claims priority to Japanese Patent Application No. 2022-211062, filed on December 28, 2022, the contents of which are incorporated herein by reference.

[0002] A bridge goes through various processes before it is erected, and some of these processes require checking or measuring the shape or deformation of the girders (bridge girders).

[0003] When constructing a structure, the structure is often surveyed and precision control is performed during construction. Surveying instruments such as metal rulers or total stations are generally used for surveying such structures (see, for example, Patent Document 1).

[0004] However, even with a total station, let alone metal rulers, it is difficult to accurately determine the shape of bridge girders and other structures that are moving, especially during construction.

[0005] Japanese Patent Application Publication No. 6-137871

[0006] According to a first aspect of the present invention, there is provided a bridge construction process up to the erection of a bridge, the process comprising: a design step; a step for producing a plurality of components based on design drawings created in the design step; a pre-assembly step for assembling the produced plurality of components into a completed or partial bridge girder in a factory and inspecting it; a transportation step for transporting the assembled completed or partial bridge girder to an erection site; and an on-site erection step for erecting the bridge at the erection site, wherein in at least some of the above-mentioned plurality of steps up to the erection of the bridge, at least one sensor is used to measure inclination information of a structure including the assembled bridge girder at a predetermined measurement point, and the measurement results are used in the above-mentioned some steps.

[0007] According to a second aspect of the present invention, there is provided a monitoring method for monitoring changes over time in the bridge girders of a bridge, the monitoring method comprising: acquiring sensor data including inclination information output from sensors that measure inclination information of the bridge girders at each measurement point using a plurality of sensors arranged two-dimensionally on the bridge girders; and repeatedly calculating the shape of the bridge girders using the acquired sensor data, thereby monitoring changes in the shape of the bridge girders over time.

[0008] According to a third aspect of the present invention, there is provided a construction method for a bridge, comprising: fabricating bridge girders for the bridge; transporting the fabricated bridge girders to an erection site; and installing the bridge girders on piers at the erection site, wherein inclination information of the bridge girders is measured by a plurality of sensors attached to a plurality of measurement points of the bridge girders installed on the piers, and the inclination information, or shape information of the bridge girders calculated from the inclination information, is used in installing the bridge girders.

[0009] 3 is a diagram showing a schematic diagram of the overall configuration of an acquisition system used to acquire the shape of a portion of an object such as a bridge girder in a bridge construction process according to one embodiment. FIG. 1 is a diagram showing a schematic diagram of the configuration of the sensor device of FIG. 1. FIG. 2 is a flowchart showing the flow of a shape acquisition method performed by the acquisition system of FIG. 1. FIG. 3 is a diagram explaining the operation of each sensor device used in the process of step S1 of FIG. 3, and is a flowchart showing a processing algorithm defined by a program executed by the CPU of the arithmetic processing unit. FIG. 4 is a diagram explaining the operation of the server 12 used in the process of step S2 of FIG. 3, and is a flowchart showing a processing algorithm of an interrupt processing routine defined by a program executed by the CPU of the server. FIG. 5 is a flowchart showing the bridge construction process up to the erection of the bridge. FIG. 7(A) is a plan view showing a portion (one span) of an assembled bridge, and FIG. 7(B) is a view of the structure of FIG. 7(A) as seen from one side (-X side) in the bridge axis direction, showing three sensors 18 arranged in the right half (+X side half) of the line GIL. ３ , 18 ４ , 18 ５10 is a diagram for explaining how to obtain the Z position of each measurement point. ２ , 18 １ 11(A) to 11(D) are diagrams illustrating the status of the construction site as the hand-stretching machine advances in the hand-stretching machine method. FIG. 13(A) to 13(D) are diagrams illustrating the change in the shape of the hand-stretching machine and the change in the relative position in the height direction between the tip of the hand-stretching machine and the upper end of the front support device as the structure including the hand-stretching machine, connecting structure, and erection girder advances in the delivery of the structure.

[0010] An embodiment will be described below with reference to FIGS. 1 to 13. FIG. 1 schematically shows the overall configuration of an acquisition system 10 used to acquire the shape of all or part of an object, such as a bridge girder, in a bridge manufacturing process according to one embodiment. The acquisition system 10 is used in each step leading up to the erection of a bridge, for example, in the temporary assembly step or the on-site erection step. Each step leading up to the erection of a bridge will be described later. A bridge refers to a structure built to provide a transportation route above a river, valley, lake, strait, canal, road, railway, etc., and includes viaducts (bridges built on the ground to secure space).

[0011] The acquisition system 10 includes a server 12, a field computer 14, a mobile terminal 16, and a plurality of sensor devices 18, all of which are connected to one another via a wide area network 13, such as the Internet. ｉ (i=1, 2, 3, ... I). ｉ are connected to a wide area network 13 via a communication line (communication network), for example, a wireless LAN.

[0012] The communication lines can also be considered to be part of a network including the wide area network 13, and therefore, hereinafter, this network will be referred to as the network 13 using the same reference numeral as the wide area network. The communication lines may all be wireless, but at least some may be wired.

[0013] The on-site computer 14 is, for example, a general desktop PC (personal computer), but is not limited to this, and the on-site computer 14 may also be a notebook PC, a tablet PC, a mobile PC, or a smartphone.

[0014] The mobile terminal 16 is carried by a worker at the site. The mobile terminal 16 is a commonly used portable computer, such as a tablet PC. The mobile terminal 16 may also be a smartphone.

[0015] In this embodiment, a plurality of sensor devices 18 ｉ In this embodiment, the output of the sensor devices 18 is provided to the server 12 via the network 13 without going through the on-site computer 14. However, this is not limiting, and the output may be provided from the on-site computer 14 to the server 12 via the network 13. In this embodiment, the on-site computer 14 is not necessarily provided. ｉ may exchange information with the server 12 via another terminal connected to the network 13 .

[0016] In this embodiment, a commonly used server computer is used as the server 12, but a cloud (computer) may also be used. The server 12 includes, for example, a CPU, ROM, RAM, HDD, etc. (storage), which are not shown. The CPU uses, for example, the RAM as a work area and executes various processing algorithms defined by various programs stored in the ROM, HDD, etc. Note that the configuration of the server 12 is not limited to that of this embodiment, and the server 12 may also include a plurality of sensor devices 18. ｉ It is sufficient that the apparatus has at least a configuration (or function) capable of calculating the shape information of the object based on the output of the above.

[0017] Furthermore, when the server 12 receives sensor data (including ID) via the network 13 as described below, it executes an interrupt processing routine to obtain shape information, such as information on the shape of one surface of the object (measurement target). The processing of the interrupt processing routine will be described in detail later.

[0018] Sensor device 18 ｉ As shown in FIG. 2, each of the sensor devices 18 includes an angle sensor 181, a processing unit 182, a display / operation unit 187, a communication unit 183, a power supply unit 184 such as a battery, and a waterproof housing 185 that houses these components. ｉ The power supply to each part of the sensor device 18 can be turned on and off by operating a power switch 186 provided on the housing 185. In this embodiment, the communication unit 183 is configured as a wireless communication unit that performs wireless communication, but the communication unit 183 is not limited to being wireless, and at least a part of it may be wired. ｉ The sensor device 18 does not necessarily have to be provided with a power switch 186, and may be configured so that the power can be turned on and off by an external operation (such as the server 12 or the mobile terminal 16). It may also be configured so that the power does not have to be turned on and off. ｉ However, the configuration is not limited to the present embodiment, and the angle sensor 181, the communication unit 183, etc. may not be integrally configured, and at least the angle sensor 181, i.e., the sensor device 18 ｉ The angle sensor 181 may have only the function of measuring angle information at the installation location. For example, the angle sensor 181 and other units (including the arithmetic processing unit 182, etc.) may be connected via a wireless or wired communication line, and measurement data from the angle sensor 181 and power supply to the angle sensor 181 may be performed via the communication line. In this case, it is not necessary to provide an other unit for each angle sensor 181, and multiple angle sensors 181 may be connected to the same other unit via a communication line. Furthermore, the function of this other unit may be provided in another terminal or the like connected to the network 13.

[0019] In this embodiment, the angle sensor 181 is, for example, a 3D MEMS (three-dimensional microelectromechanical system) tilt angle (inclination angle) sensor. The 3D MEMS tilt angle sensor is a precision tilt sensor developed using 3D MEMS technology. The 3D MEMS tilt angle sensor requires extremely low power consumption, in the microampere range, making it suitable for wireless applications. For example, the angle sensor 181 includes two MEMS acceleration sensors with symmetric output characteristics and an ASIC. The sensor outputs information on tilt angles (α, β, γ) in three directions (θx, θy, and θz). The θx, θy, and θz directions are the tilt and rotation directions around the X, Y, and Z axes of a Cartesian three-dimensional coordinate system (see FIGS. 7A and 7B ), with the Z axis being the direction of gravity.

[0020] The angle sensor is not limited to a 3D MEMS tilt angle sensor, and other types of three-dimensional tilt angle sensors may be used. Furthermore, the angle sensor is not limited to a three-dimensional tilt angle sensor, and a two-dimensional tilt angle sensor or a one-dimensional tilt angle sensor may be used depending on the object to be measured. In this case, a two-dimensional tilt angle sensor and a one-dimensional tilt angle sensor may be combined, or a plurality of two-dimensional or one-dimensional tilt angle sensors may be combined. For example, a two-dimensional tilt angle sensor may be a 2D MEMS tilt angle sensor having two pairs of electrodes each consisting of a fixed electrode and a movable electrode, measuring the amount of change in capacitance between the electrodes due to a change in positional relationship caused by tilting based on the positional relationship between the electrodes when horizontal, and converting the change into an angle.

[0021] The arithmetic processing unit 182 is formed of, for example, a microcontroller (MCU) and has a CPU, memory devices (RAM, ROM), an input / output circuit, and a timer circuit (not shown). The arithmetic processing unit 182 executes a processing algorithm defined by a program stored in the ROM. Note that, instead of providing the arithmetic processing unit 182, an ASIC built into the angle sensor 181 may also have the function of the arithmetic processing unit 182.

[0022] Here, the sensor device 18 ｉFor example, if the object is made of a material that can be secured by screws, such as metal, the sensor device 18 can be attached to the object using screws (including bolts). ｉ In addition, depending on the type of object and the method of use, the sensor device 18 can be fixed to the object by using the magnetic force of a magnet instead of or in addition to screwing or gluing. ｉ In the following description, the sensor device 18 ｉ Sensor 18 ｉ It is abbreviated as:

[0023] Next, the flow of the shape acquisition method performed by the acquisition system 10 will be explained based on the flowchart in Fig. 3. Prior to explaining the flow of shape acquisition, the prerequisites for starting shape acquisition will be explained. As a prerequisite, a target object, for example, a bridge girder, is provided with a plurality of sensors 18. ｉ are arranged in a predetermined arrangement such as a linear arrangement or a matrix arrangement. ｉ It is assumed that the sensors 18 are calibrated in advance (before installation) to prevent measurement errors. ｉ The arrangement is not limited to being regular, but may be irregular.

[0024] Also, each attached sensor 18 ｉ The switches 186 are turned on by the workers at the respective sites to turn on the power, and necessary initial settings are made in advance so that the sensors 18 can communicate via the network 13. ｉ The initial setting of the sensor 18 is performed via the display operation unit 187. ｉ The identification information includes inputting the identification information of the sensor 18. ｉ and the identification number of the sensor 18 in the object. ｉ and information on the installation position of each sensor 18. ｉ Identification information is input individually to each of the arithmetic processing units 182, and each arithmetic processing unit 182 stores the input identification information in its internal memory (RAM). The identification information is used to manage which sensor is attached where.

[0025] By completing the initial setting, each sensor 18 ｉ After the initial setting, each sensor 18 ｉ The switch 186 is maintained in an ON state. ｉ However, if the power supply can be turned on and off by external operation, the power supply may be set to OFF once after the initial setting.

[0026] Based on this premise, the tilt angle information at each of a plurality of measurement points arranged on one surface of the object is obtained by a plurality of sensors 18. ｉ (Step S1 in FIG. 3). After acquiring the tilt angle information at each measurement point on the object, the acquired tilt angle information is used to obtain shape information for one surface of the object (Step S2 in FIG. 3).

[0027] In this embodiment, the above steps S1 and S2 are performed by the shape acquisition system 10, and therefore, the operation of each component of the shape acquisition system 10 will be described below.

[0028] First, the sensors 18 used in the process of step S1 in FIG. ｉ The operation of the method will be described with reference to the flowchart in Fig. 4. This flowchart shows a processing algorithm defined by a program executed by the CPU of the arithmetic processing unit 182. The processing algorithm shown in the flowchart in Fig. 4 is started when an instruction to start measurement is input. Note that the instruction to start measurement is given to one group of sensors 18 arranged on the same object to be measured. ｉ In this embodiment, as an example, a plurality of sensors 18 are arranged on one line on one surface of the same object. ｉ In addition, a plurality of sensors 18 arranged in a matrix in a predetermined area set on one surface of the same object may be used. ｉ In other words, the sensors may be grouped arbitrarily.

[0029] First, in step S3, the angle sensor 181 is instructed to perform measurement, and information on the tilt angle (here, tilt angles in at least two directions, for example, the θx direction and the θy direction) measured by the angle sensor 181 is acquired. In the next step S4, an ID (identification code) is linked to the acquired output information, and the data is sent to the server 12 via the communication unit 183 and the network 13 as a single piece of sensor data. Here, the ID is a number (code) that is input by the operator at the time of initial setup and is created based on the identification information stored in the RAM. When the processing of step S4 is completed, the processing ends. As a result, the sensor 18 ｉ The processes in steps S3 and S4 are performed for all the sensors 18. ｉ The server 12 stores the received sensor data in a predetermined storage area of ​​the RAM in sequence. When multiple pieces of sensor data are received simultaneously, the server 12 stores the sensor data simultaneously in a predetermined storage area of ​​the RAM in a time-sharing manner.

[0030] Next, the operation of the server 12 used in the process of step S2 in Fig. 3 will be described with reference to the flowchart in Fig. 5. This flowchart is a flowchart showing the processing algorithm of an interrupt processing routine defined by a program executed by the CPU of the server 12. This interrupt processing routine is executed by detecting the presence or absence of all the sensors 18 belonging to one group arranged on the target object. ｉ This is executed every time the sensor data acquisition from the

[0031] First, in step S5, the acquired sensor data is used to calculate the two-dimensional shape of a line set on one surface (measurement surface) of the object as shape information of the object (first calculation method). Alternatively, if a group of sensors is two-dimensionally arranged on one surface (measurement surface) of the object, the three-dimensional shape of the measurement surface (the in-plane distribution of deviations of each point from the reference surface) is calculated (second calculation method). Then, in the next step S6, the calculated shape information data is associated with the line or surface being calculated and stored in storage (such as a HDD), and the interrupt processing routine is terminated. Note that the three-dimensional shape of the measurement surface may also be (roughly) calculated using the first calculation method by processing measurement information obtained from multiple sensors arranged on different lines on the measurement surface.

[0032] 5 is performed every time sensor data is acquired. That is, every time sensor data is acquired, shape calculation and storage of the calculation result associated with the calculation target are repeatedly performed. However, shape calculation does not necessarily have to be performed every time sensor data is acquired, and the shape calculation timing can be set arbitrarily.

[0033] Therefore, a rewritable data table associated with the calculation target may be prepared in advance in a specified area of ​​the storage, and when storing the calculation results, the area associated with the calculation target may be repeatedly overwritten (i.e., the stored contents may be updated).

[0034] In this embodiment, the server 12 has a database including the above-mentioned data table that associates the latest information stored in the storage with the design data, and updates the database every time a measurement is completed. In this case, based on the created and updated database, it is also possible to monitor changes over time in the shape of the object (e.g., bridge girder) for which the calculation target is set.

[0035] Before the first measurement of the object is started, provisional data is stored in the area inside the database where the measurement result data is stored. Then, when the first measurement is completed, the first update of the database is performed.

[0036] If necessary, each time the database is updated, the server 12 may transmit information including the measurement results to the on-site computer 14 via the network 13. The database does not need to be updated in synchronization with the shape calculation.

[0037] Figure 6 shows a flowchart of the bridge construction process up to the erection of the bridge. First, in the first step S11, the design step, the bridge is designed by a construction consultant or the like. The design includes basic planning, investigation and surveying, preliminary design, detailed design, landscape design, etc.

[0038] In the next step S12, the full-scale step, the exact dimensions of the bridge girder components are determined based on the design drawings, taking into account shrinkage and distortion due to welding and margins in the event of cutting, and work is then done to create the materials (full-scale) necessary for production, such as processing, welding, etc., such as NC full-scale, which uses a computer to automatically create drawings.

[0039] In the next step S13, the marking step, the data created in the original size step is used to mark the steel plate with cutting lines, drilling positions, etc. Recently, marking is performed automatically using an NC marking machine directly from the NC original size data.

[0040] In the next step S14, a cutting step, the steel plate is cut. Cutting methods include gas cutting, plasma cutting, laser cutting, and mechanical cutting. These cutting methods are used in combination depending on the size and shape of the steel plate to be cut.

[0041] In the next step S15, a drilling step, bolt holes are drilled in the steel plates. A common method for joining bridge girder components on-site is to fasten connecting plates (splice plates) with high-strength bolts, which requires drilling bolt holes in the steel plates. An NC girder radial drilling machine, an NC radial drilling machine, or other radial drilling machines, or a simple, portable drilling device, may be used.

[0042] In the next step S16, the assembly and welding step, the individual components that have been cut and drilled are welded and assembled. This completes the bridge girder. Depending on the work involved, welding is performed using an automatic welding machine or by hand.

[0043] In the next step, S17, the temporary assembly step, temporary assembly is performed, in which the individual components that have been welded and assembled are assembled into the completed or partial form of the bridge girder. The shape and dimensions of the components are inspected to ensure there are no problems with erection on site. There are two types of temporary assembly: "actual temporary assembly," in which the components are actually assembled, and "temporary assembly simulation." In the temporary assembly simulation, a computer-based three-dimensional measurement system is used to perform numerical temporary assembly on a desk based on measurement data of the components.

[0044] In the next step S18, the painting step, after the temporary assembly inspection is complete, the components are disassembled again and painted. In the next step S19, the transportation step, the painted components are brought in to coincide with the on-site erection time. Transport by land using trucks and trailers is the norm, but marine transport by ship may also be used depending on the erection conditions. In the next step S20, the on-site erection step, the bridge is erected using various erection methods. Erection methods include the launching method, truck crane vent method, cable erection method, traveler crane method, and floating crane method.

[0045] There are cases where it is not possible to install vents under bridges due to the topographical environment of rivers and oceans, or traffic conditions of railways and roads, and in such cases the launching method is used. The launching method is a construction method in which the erection girders (bridge girders) are assembled in advance at an adjacent location and then launched to lay the bridge. Details of erection methods other than the launching method will not be explained here.

[0046] In the bridge manufacturing process described above, in this embodiment, the sensor 18 is installed during the temporary assembly in the factory (step S17). ｉ In this embodiment, the temporary assembly is not a temporary assembly simulation, but an actual temporary assembly in which components are actually assembled. The components are actually assembled, and the shape and dimensions of the assembled components, for example, the bridge girder, are inspected to confirm that there are no problems with erection on site. The placement of sensors in the temporary assembly may be substantially the same as when the bridge girder was erected, and the sensors may remain attached to the bridge girder after dismantling, and the bridge girder may be transported to the construction site. Here, if painting is performed after dismantling, the sensors may be reinstalled after painting.

[0047] One example of measuring the shape of a bridge girder during temporary assembly is measuring the camber of a bridge girder. If a bridge girder is designed to be straight during design, after construction, the bridge girder will bend in the center and assume a downward convex shape due to the distributed load caused by its own weight. Normally, it is desirable for a bridge girder to be straight in side view after construction, especially in the direction of the bridge axis, so the bridge girder is designed in advance to have a bow (upward convex shape) taking into account the effect of its own weight after construction. Creating a bow during design is called adding camber. Camber measurement refers to measurements taken to confirm that the camber shape is as designed.

[0048] In this embodiment, the camber measurement is performed using a plurality of sensors 18 ｉThis is done as follows using the following. Figure 7(A) shows a plan view of a portion (one span) of an assembled bridge. Here, one span refers to the portion of the bridge that is erected between adjacent piers. Figure 7(B) shows a view of the structure in Figure 7(A) from one side (-X side) in the bridge axis direction. Here, the direction of gravity is defined as the Z axis direction, the bridge axis direction perpendicular to the Z axis is defined as the X axis direction, and the direction perpendicular to the X axis in a plane perpendicular to the Z axis is defined as the Y axis direction.

[0049] In FIG. 7A, the bridge girder 53 ｊ 7(A), four lines G1L, G1R, G2L, and G2R extending in the X-axis direction and five lines C14, C15, C16, C17, and C18 extending in the Y-axis direction are set on the upper surface of each of the four lines (j=1, 2, ...) shown in FIG. 7(B). The positions of the lines G1L, G1R, G2L, and G2R in the Y-axis direction (Y positions) are shown in FIG. 7(A). As a preparatory step for camber measurement, 20 sensors 18 are placed at the intersections of the four lines extending in the X-axis direction and the five lines extending in the Y-axis direction, as shown in FIG. 7(A). ｉ (i = 1 to 20) are attached to each sensor 18. ｉ The mounting positions of the sensors 18 ｉ Bridge girder 53 ｊ The tilt angle is measured by each sensor 18. ｉ The correspondence between the sensor 18 and the measurement point is managed by the server 12. ｉ The position on the top surface of the bridge girder where the sensor 18 is to be attached is determined in advance based on the design information, and a mark is attached to the determined position during the manufacturing stage of each member prior to temporary assembly. ｉ The worker in charge of installing the sensors 18 ｉ are individually attached to the positions of the marks, and the sensors 18 ｉ The information on the respective mounting positions is set to be input as an initial setting via the display operation unit 187. ｉThe sensor data including ID information including the sensor number and attachment position information as an ID is output to the server 12.

[0050] The server 12 has 20 sensors 18 １ ~18 ２０ Using the above, the bridge girder 53 at each measurement point ｊ The tilt angle of the upper surface is measured, and each sensor 18 ｉ The sensor data output from the sensor is acquired and stored in a predetermined area in the memory.

[0051] Next, the server 12 detects the three sensors 18 arranged on the right half (+X side half) of the line GIL. ３ , 18 ４ , 18 ５ The tilt angle value β in the θy direction included in each sensor data ３ ~β ５ Based on this, the sensor 18 is positioned on the ZX coordinate system shown in FIG. ３ , 18 ４ , 18 ５ Each measurement point P ３ , P ４ , P ５ Find the Z position of

[0052] FIG. 8 shows the bridge girder 53 ｊ 8 is a ZX coordinate system with the origin 0 set at the center point of the line GL1, the horizontal axis being the Z axis, and the vertical axis being the X axis. A curve C in FIG. 8 corresponds to the right half of the line GL1 in FIG. 7A.

[0053] As shown in FIG. ３ , 18 ４ , 18 ５ Each measurement point (sensor 18 ３ , 18 ４ , 18 ５ The bridge girder 53 to which each of the ｊ Position on the surface line G1L) ３ , P ４ , P ５ The coordinate values ​​of these measurement points on the XZ coordinate system are P ３ (Z ３ , X ３ ), P ４ (Z ４ , X４ ), P ５ (Z ５ , X ５ ) and then, by calculation, the measurement point P ４ Z position Z ４ , measurement point P ５ Z position Z ５ can be found as follows:

[0054] Z ４ =Z ３ +tan{(β ３ +β ４ ) / 2}×(X ４ -X ３ )……(1) Z ５ =Z ４ +tan{(β ４ +β ５ ) / 2}×(X ５ -X ４ )……(2)

[0055] In FIG. 8, for the sake of visual clarity, the sensor 18 ３ The tilt angle β measured at ３ is shown larger than it actually is, but in reality, the inclination angle β ３ is a small angle. Therefore, point P ３ Z position Z ３ Is Z ３ ≒X ３ tanβ ３ ≒0, and by substituting this into equation (1), Z ４ is a known value X ４ , X ３ , β ３ , β ４ It can be calculated from the above, and the calculated Z ４ By substituting into equation (2), Z ５ is a known value Z ４ , X ４ , X ５ , β ４ , β ５ It can be calculated from

[0056] Similarly, the server 12 detects the remaining two sensors 18 arranged on the line GIL. ２ , 18 １ Each measurement point (sensor 18 ２ , 18１ The bridge girder 53 to which each of the ｊ Position on the surface line G1L) P ２ , P １ The coordinate values ​​of P on the XZ coordinate system ２ (Z ２ , X ２ ), P １ (Z １ , X １ ) and calculate the Z positions of these measurement points. In this case, line D shown in FIG. 9, which corresponds to the left half of line GL1 in FIG. 7A, is used.

[0057] By calculation, point P １ Z position Z １ can be calculated as follows: Z １ =Z ２ +tan{(β １ +β ２ ) / 2}×(X １ -X ２ ) (3) In FIG. 9, in order to make the explanation easier to understand visually, the sensor 18 ２ The tilt angle β measured at ２ is shown larger than it actually is, but in reality, the inclination angle β ２ is a small angle. Therefore, point P ２ Z position Z ２ Is Z ２ ≒-X ２ tanβ ２ 0, and by substituting this into equation (3), Z １ is a known value X ２ , X １ , β １ , β ２ It can be calculated from

[0058] As a result, five sensors 18 １ ~18 ５ Each measurement point P １ ~P ５ Z coordinate value Z １ ~Z ５ Also, the measurement point P １ ~P ５ The X coordinate value of the point P is known because it can be calculated from the design value. １ (Z １, X １ ), P ２ (Z ２ , X ２ ), P ３ (Z ３ , X ３ ), P ４ (Z ４ , X ４ ), P ５ (Z ５ , X ５ ) is fitted with an appropriate function to obtain a function Z=f １Ｌ (X) can be found.

[0059] Similarly, the server 12 detects the five sensors 18 arranged on the line GIR. ６ ~18 １０ The tilt angle value β in the θy direction included in each sensor data ６ ~β １０ Based on this, a function Z=f representing the shape of the line G1R is １Ｒ (X) can be found.

[0060] Similarly, the server 12 detects the five sensors 18 arranged on the line G2L. １１ ~18 １５ The tilt angle value β in the θy direction included in each sensor data １１ ~β １５ Based on this, a function Z=f ２Ｌ (X) can be found.

[0061] Similarly, the server 12 detects the five sensors 18 arranged on the line G2R. １６ ~18 ２０ The tilt angle value β in the θy direction included in each sensor data １６ ~β ２０ Based on this, a function Z=f representing the shape of the line G2R is ２Ｒ (X) can be calculated. By comparing the calculated function with the design value of each line, the bridge girder 53 ｊ If necessary, the degree of agreement between the actual camber and the design value can be calculated by using the function Z=g １４ (Y) to Z = g １８(Y) to the sensor 18 ｉ The tilt angle α included in the sensor data ｉ In the camber measurement, the origin of the coordinate system for determining the function representing the shape of each line is not limited to the center point of the line described above, and may be set to any position (point).

[0062] In addition, sensor 18 １ ~Sensor 18 ２０ The sensor data output from the sensor 18 is functionally fitted with a predetermined function Z=f(X, Y). １ ~18 ２０ Bridge girder 53 with ｊ A function representing the shape of one surface (measurement surface) of the line G1L may be calculated. Typical functions used in this case include polynomial functions, such as Fourier functions or differential Zernike functions. Then, by substituting the Y coordinate (Y1) of line G1L into the function Z = f(X, Y) representing the shape of the calculated measurement surface, Z = f(X, Y1) is calculated, which becomes a function in the XZ coordinate system representing line G1L. Similarly, functions in the ZX coordinate system representing lines G1R, G2L, and G2R can be calculated. Furthermore, by individually substituting the X coordinates of lines C14 to C18 into the function Z = f(X, Y) representing the shape of the calculated measurement surface, functions in the YZ coordinate system representing lines C14 to C18 can be calculated.

[0063] Here, function fitting refers to a technique in which multiple data are plotted on a predetermined coordinate system, a function system that passes through the multiple plot points (data points) is approximated with a predetermined polynomial (including undetermined coefficients), the undetermined coefficients are determined using, for example, the least squares method, and the polynomial function after the coefficients have been determined is used as the target function. It is also possible to simply obtain inclination information (convex / concave information) in one direction from the output of each sensor array without performing fitting. In this case, by arranging the sensors in a grid, multiple lines (vertical, horizontal, and diagonal) connecting the multiple sensors can be set, and the inclination information for each line can be obtained.

[0064] In this embodiment, the sensor 18 is also used during the on-site installation (step S20) described above. ｉAmong various construction methods, the sensor 18 is used to take the case where a bridge is constructed by a hand-stretching machine as an example. ｉ An example of how to use the measurement results will be explained below.

[0065] Among the launching methods, the "hand-launching method" is one in which the erection girders are assembled before bridge erection work begins, and then the erection girders are launched using a hand-launching machine. There are various methods for erection work. The hand-launching method is selected based on conditions such as the topographical conditions and traffic environment. The hand-launching method has some disadvantages, such as the need for advance consideration and temporary facilities, and the possibility of a longer construction period. However, because there is no need to install heavy machinery under the bridge or create vents, it has the great advantage of being able to shorten the period of traffic restrictions under the bridge compared to other methods, thereby minimizing traffic losses.

[0066] Figure 10 shows a flow chart showing the flow of the hand-stretching machine method. Figures 11(A) to 11(D) show the situation at the construction site (on-site) as the hand-stretching machine method progresses. Here, it is assumed that some bridge girders (hereinafter also referred to as girders) 53 have already been erected. １ The erection of the above is assumed to be completed.

[0067] First, in step S21, a step of assembling girders, hand stretchers, etc. is carried out. In this step S21, the bridge is constructed at a location adjacent to the location where the bridge is to be built, for example, at a location where an already-built girder (53 １ ) is used as a work space, and the erection girder (53 ２ ) and hand-stretching machine 50 are assembled, and the launching equipment is installed. Here, the hand-stretching machine refers to the equipment attached to the tip of the erection girder in order to safely launch the bridge body. The hand-stretching machine is constructed from light materials because it is affected by its own weight. The launching equipment includes, for example, a track facility installed on the top surface of the erected girder and extending in the launching direction, a self-propelled carriage that moves under its own power along the track facility, and a driven carriage that moves following the self-propelled carriage. The erection girder is placed on these self-propelled carriages and driven carriages and is supported from below. After the erection girder is supported, the hand-stretching machine is connected to the tip of the erection girder via a connecting structure.

[0068] In FIG. 11(A), a hand stretching machine 50 is connected to a connecting structure 51 to send out a next girder (construction girder) 53. ２ 1 is shown connected to the

[0069] In the next steps S22 and S23, the steps of extending the hand stretcher and sending out the girder are carried out. In step S22, the hand stretcher is extended to the already installed pier. That is, the hand stretcher connected to the tip of the erected girder begins to be sent out so that the tip of the hand stretcher 50 reaches the top of the already installed pier. The sending out is initially carried out by the aforementioned sending out equipment installed on the already erected girder. The driving source for the sending out is a self-propelled cart, but this is not limited to this, and a winch or jack can also be used as the driving source for the sending out device, and the self-propelled cart, winch, or jack can be used alone or in combination depending on the situation.

[0070] The tip of the hand stretching machine 50 is connected to the already installed pier (80 １ ) when it reaches the top of the erection girder 53 ２ The structure consisting of the connecting structure 51 and the hand stretching machine 50 is supported on both ends by the self-propelled carriage and the driven carriage of the sending equipment and the front support device described later. In this supported on both ends, the hand stretching machine 50 is connected to the top end of the erection girder 53. ２ is sent out.

[0071] FIG. 11(B) shows the erection girder 53 ２ The tip of the first pier 80 １ As shown in FIG. 11(B), when the hand stretching machine 50 or the like is sent out, the piers 80 located in front of the sending direction indicated by the arrows in FIG. 11(B) are ｐ The upper end of the front support device 82 provided at the top of (p=1, 2, 3, ...) is connected to the erection girder 53 to be sent out. ２Some of the members constituting the front support device 82 are driven upward by a jack so as to be positioned at approximately the same height as the underside of the pier 80. ｐ The structure includes a jack 82A attached to the pier 80, a support 82B functioning as a steel bent that can be raised and lowered by the jack 82A, and a delivery stage 82C attached to the top of the support 82B. ｐ The delivery stage 82C is raised and lowered integrally with the support 82B by the jack 82A, and the upper end of the delivery stage 82C is connected to the erection girder 53. ２ (See FIG. 11B.) A front installation device having a similar configuration to the front support device 82 is disclosed in, for example, Japanese Patent Application Laid-Open No. 2007-291719.

[0072] The sending out of one erection girder is completed, i.e., the erection girder 53 ２ The rear end of the existing girder 53 １ to a position that coincides with the front end of the erection girder 53 ２ When the beam is sent out, a step of dismantling the hand stretching machine is executed in step S24. That is, the hand stretching machine 50 and the connecting structure 51 are dismantled and removed. ２ 1 shows the state where the delivery of the yarn has been completed, that is, the state immediately before the hand stretching machine 50 and the connecting structure 51 are disassembled.

[0073] Then, when the hand stretching machine 50 and the connecting structure 51 are dismantled and removed, the erection girder 53 is ２ 11(D) , the step of lowering the erection girder 53 is performed (see the downward arrow in FIG. 11(C)). ２ The existing girder 53 descends １ In this embodiment, as shown in FIG. 11(C), the pier 80 １ , 80 ２ , 80 ３ The erection girder 53 is supported by a plurality of front support devices 82 provided on each of the ２Therefore, by simply lowering the sending stage 83C integrally with the support columns 82B by the jacks 82A provided on each front support device 82, the erection girder 53 supported by the plurality of sending stages 83C can be ２ It is possible to lower the

[0074] After that, all the planned erection girders 53 ｐ Steps S21 to S25 are repeated until the erection of the girder is complete. At this time, the top surface of the erected girder, which is located at the front end in the sending direction and has just been erected, is used as a work space, and the next erection girder and hand stretching machine to be erected are assembled. After the erection of all the girders to be erected is completed, the deck work, ground covering work, and bridge accessory work are carried out, and after a final inspection, all construction work is completed.

[0075] During the sending out, the hand stretching machine 50 (or the hand stretching machine 50 and the erection girder 53 depending on the situation) ２ ) is in a cantilevered state (overhanging beam state), so the tip portion bends downward. In consideration of this point, a hand stretching machine 50 is used that is configured to be able to eliminate the influence of deformation due to bending under its own weight.

[0076] 12 shows an example of the configuration of a hand-stretching machine 50. The hand-stretching machine 50 comprises a hand-stretching machine main body 52, a hand-stretching machine movable part 54, and a hinged truss part 56. The hinged truss part 56 is disposed between the hand-stretching machine main body 52 and the hand-stretching machine movable part 54. The hand-stretching machine main body 52 is supported by a bridge girder 53. ２ 12A, see FIG. 11A) via a connecting structure 51.

[0077] The hinge-connected truss section 56 has a main body section upper surface connecting member 56a, a movable section section upper surface connecting member 56b, and an expandable upper and lower connecting member 64. The main body section upper surface connecting member 56a is connected to the upper surface member 52a of the hand stretching machine main body section 52 by a hinge 58. The movable section section upper surface connecting member 56b is connected to the upper surface member 54a of the hand stretching machine movable section 54 by a hinge 60. One end (upper end) of the expandable upper and lower connecting member 64 is connected to the main body section upper surface connecting member 56a and the movable section section upper surface connecting member 56b by an upper hinge 62. The other end (lower end) of the expandable upper and lower connecting member 64 is connected to one end of the lower surface member 52c of the hand stretching machine main body section 52 and one end of the lower surface member 54c of the hand stretching machine movable section 54 by a lower hinge 66.

[0078] The hinged truss section 56 is provided with an expandable upper and lower connecting member 64 to form a pantograph jack, and by operating this pantograph jack (particularly the expandable upper and lower connecting member 64), the tip of the hand stretching machine movable section 54 can be moved to the bridge girder 53. ２ 12, see FIG. 11A) and can rotate up and down relative to the delivery direction of the hand stretching machine main body 52 (see the outline arrow in FIG. 12).

[0079] The telescopic upper and lower connecting members 64 are made up of hydraulic jacks with clevises on both ends. A typical short hydraulic jack with clevises on both ends is used, but the length between its pins (here, the length between the upper hinge 62 and the lower hinge 66) is longer than the distance between the upper and lower members of the hand stretching machine main body 52 and the hand stretching machine movable part 54. Therefore, even in the initial state, the upper members 56a, 56b of the hinge-connected truss part 56 have a mountain-like shape (see Figures 13(A) and 13(D)).

[0080] A wire 68 is arranged along the upper surface of the hinged truss section 56, and a wire clamp jack 70 for pulling in the wire 68 is provided on the upper surface member 54a of the hand stretching machine movable section 54. One end of the wire 68 is fixed to the hand stretching machine main body section upper surface member 52a, and the middle section is inserted into holes in guide sections 72a, 72b protruding from the main body section side upper surface connecting member 56a and the movable section side upper surface connecting member 56b of the hinged truss section 56, respectively.

[0081] The wire clamp jack 70 is free when the telescopic upper and lower connecting member 64 is extended, and when it is retracted, it retracts the wire 68 by changing the clamp and extending or retracting the jack, thereby assisting the retraction of the telescopic upper and lower connecting member 64. Note that Figure 12 shows the telescopic upper and lower connecting member 64 in a state where it is extended by a predetermined amount.

[0082] Although not shown in FIG. 12, in this embodiment, a plurality of sensors 18 are provided on the upper surface of each of the lower surface member 52c of the hand-stretching machine main body 52 and the lower surface member 54c of the hand-stretching machine movable part 54. ｉ are arranged at predetermined intervals along the longitudinal direction (see FIG. 13(A)).

[0083] Therefore, in the same manner as in the case of the camber measurement described above, the shapes of the lower surface members 52c and 54c when deformation due to the weight of the hand stretching machine 50 occurs, and the function representing the shapes, are measured by the plurality of sensors 18. ｉ The tilt angle can be calculated using the information on the tilt angle at each measurement point measured in step 1.

[0084] At this time, the Z position of the bottom hinge 66 located at the tip of the bottom member 52c (based on the point at the base end of the bottom member 52c) can be calculated using a function that represents the shape of the bottom member 52c. Furthermore, the Z position of the point at the tip of the bottom member 54c (based on the Z position of the bottom hinge 66) can be calculated using a function that represents the shape of the bottom member 54c. Ｔ Therefore, by adjusting the length of the telescopic upper and lower connecting member 64, that is, the hydraulic jack with clevises at both ends that constitutes the telescopic upper and lower connecting member 64, the Z position Z Ｔcan be set to a desired position.

[0085] More specifically, as shown in FIG. 13A, the hand stretching machine 50 is sent out and the pier 80 ｐ As the hand stretcher 50 approaches the upper front support device (hereinafter also referred to as the support member) 82, it bends and deforms due to its own weight, and the tip of the lower surface member 54c is positioned by H below the upper surface of the delivery stage 82C.

[0086] However, in this embodiment, at any time during the delivery of the hand-stretching machine 50, the server 12 detects the number of sensors 18 disposed on the lower surface member 54c and the lower surface member 52c. ｉ Based on the sensor data output from the sensor, the Z position Z of the tip point of the lower surface member 54c is calculated by the above-mentioned method. Ｔ Therefore, when the hand stretching machine 50 approaches the support member 82 within a predetermined distance, the Z position Z Ｔ Based on the calculation result, the expandable upper and lower connecting members 64 are extended to deform the hinged truss section 56. As a result, the hand-stretching machine movable section 54 rotates counterclockwise around the lower hinge 66, and the tip of the hand-stretching machine movable section 54 jumps up.

[0087] From this point onwards, the server 12 continues to monitor the plurality of sensors 18 until the hand stretcher 50 reaches the support member 82. ｉ Based on the sensor data output from the Ｔ is repeatedly calculated, and the length of the telescopic upper and lower connecting members 64 is adjusted based on the calculation results (i.e., the hydraulic jack with clevises on both ends is controlled). As a result, as shown in Figure 13(C), when the tip of the hand stretching machine 50 has been sent out to a position where it reaches the support member 82, the tip of the lower surface member 54c of the hand stretching machine movable part 54 can be smoothly placed on the support member 82. In the state of Figure 13(C), the hand stretching machine 50, the connecting structure 51, and the erection girder 53 ２ The structure including the above is supported at both ends (close to being supported at both ends).

[0088] 13(D), the server 12 controls the hydraulic jack with clevises on both ends so that the length of the extendable upper and lower connecting members 64 returns to the initial state. As a result, the shape of the hand stretching machine 50 returns to the state before sending out, and the lower hinge portion 66 of the hinged truss portion 56 is raised and positioned at approximately the same height as the upper surface of the support member 82.

[0089] In addition, in accordance with the contraction of the telescopic upper and lower connecting members 64, the wire clamp jacks 70 are re-clamped and the jacks are extended and retracted to retract the wires 68, assisting the operation of contracting the telescopic upper and lower connecting members 64. Therefore, even if a malfunction occurs in the telescopic upper and lower connecting members 64, the tension of the wires 68 caused by the retraction of the wire clamp jacks 70 can prevent the telescopic upper and lower connecting members 64 from extending, so the truss shape can be maintained and safety can be ensured.

[0090] Furthermore, since the tension of the wire 68 acts as a pushing force when the hinge-connected truss section 56 is in a mountain-shaped state, it is desirable from a safety standpoint that the upper surface member remain in a mountain-shaped state as in this embodiment even when the telescopic upper and lower connecting member 64 is contracted. However, this is not limited to this, and it is possible to use the wire clamp jack 70 and wire 68 to assist in the operation of contracting the telescopic upper and lower connecting member 64 even if the length of the telescopic upper and lower connecting member is configured to be equal to the distance between the upper and lower surface members of the hand-stretching machine main body section and the hand-stretching machine movable section.

[0091] In the above embodiment, a hand-stretching machine of the type comprising a hand-stretching machine main body, a hand-stretching machine movable part, and a hinged truss part interposed between them was described. However, this is not limited to this, and a hand-stretching machine consisting of a completely integrated girder structure that does not have a hinged truss part and is extremely light compared to a bridge may also be used. An example of this type of hand-stretching machine is disclosed in, for example, Japanese Patent Application Laid-Open No. 2001-193016. In this publication, a jack is provided on the connecting structure side of the hand-stretching machine, and a cable attached to the jack is fastened to the top of the tip of the hand-stretching machine with a distance between it and the hand-stretching machine, and the cable is tensioned by the jack, so that an upward bending force can be applied to the hand-stretching machine. In this hand-stretching machine as well, multiple sensors 18 ｉBy arranging the sensors 18 along the longitudinal direction, it is possible to calculate the shape of the hand stretcher (tip) when it is deflected and deformed due to the action of its own weight and the Z position of the tip. ｉ Measurements are taken using the above method and the shape is calculated using the measurement results, and the upward bending force applied to the hand-stretching machine is adjusted based on the calculation results, thereby eliminating the deflection of the hand-stretching machine, making the underside of the hand-stretching machine horizontal, and setting its height slightly above the height of the upper surface of the support member 82, and allowing the tip of the underside of the hand-stretching machine to be placed on the support member 82.

[0092] So far, we have explained the method of sending out using a hand stretching machine. However, in a sending out method that does not use a hand stretching machine, when sending out the erection girder, multiple sensors 18 ｉ In this case, the erection girder is in a cantilevered state during launching, so it is advisable to adjust the deflection amount as needed to ensure smooth launching.

[0093] In the above description, multiple sensors 18 ｉThe shape of the structure to be sent out when it is deformed by its own weight is calculated using the sensor data output from each of the sensors, and the shape of the structure to be sent out (or the height of its tip (Z position)) is adjusted based on the calculation result. However, instead of this, the height of the sending stage 82C (and the support columns 82B), which can be raised and lowered by the jacks 82A of the front support device 82, may be adjusted based on the calculation result of the shape of the structure to be sent out when it is deformed by bending. Alternatively, the shape of the structure to be sent out (or the height of its tip (Z position)) and the height of the sending stage 82C (and the support columns 82B) of the front support device 82 may be adjusted based on the calculation result of the shape of the structure to be sent out when it is deformed by bending. Note that the sensor outputs may be monitored during the sending out of the bridge girder, and the measured values ​​of the sensors may be compared with their initial values ​​as needed. If the fluctuation of the measured values ​​exceeds a threshold, an alarm may be issued. Alternatively, the sensor output can be monitored while the bridge girder is being sent out, and the bridge girder shape information obtained from the sensor's measurements can be compared with the initial shape information as needed. If the amount of change in shape exceeds a threshold, an alarm can be issued. The alarm can be a sound (including a voice message) or a warning message can be displayed on the screen. Since the shape information can be expressed by a predetermined approximation function, the amount of change in shape can be determined by focusing on the coefficient of a predetermined term in the approximation function.

[0094] In addition, up until now, when implementing the sending-out method, the sensor 18 ｉ However, in the case of carrying out the truck crane vent method, the cable erection method, the traveler crane method, the floating crane method, and the like other than the sending-off method, it is possible to use a plurality of sensors 18 ｉ The shape of the bridge girder during construction may be calculated as needed using the above formula.

[0095] Incidentally, up until now, a plurality of sensors 18 have been attached to the object. ｉ The case where the shape of the object is obtained by attaching a sensor 18 to the object has been described. ｉIt is also possible to attach one sensor to measure the inclination (θx, θy) of the object. For example, when a bridge girder is launched using a launching facility, the erection girder to be launched is supported from below by a support device mounted on a self-propelled carriage and a driven carriage, and this support device includes multiple jacks mounted on each of the self-propelled carriage and the driven carriage. During launching, the inclination of the erection girder is measured and the multiple jacks are controlled based on the measurement results so that the erection girder always maintains a horizontal position. In this case, the inclination of the erection girder is measured using a sensor 18. ｉ Only one may be used.

[0096] In addition, even after the bridge construction work is completed, multiple sensors 18 ｉ The sensors 18 are always attached in a predetermined arrangement. ｉ The server 12 repeatedly acquires sensor data from the sensors 18 and calculates the shape of the bridge girder using the acquired sensor data at a predetermined sampling interval, thereby making it possible to monitor changes in the shape of the bridge girder over time. If the monitoring results indicate that the bridge girder has undergone a change in shape that exceeds expectations, traffic volume on the bridge girder (road) may be restricted (including prohibiting traffic). Alternatively, the monitoring results may be used to monitor the occurrence of abnormalities in the bridge (bridge girder). In this case, it is desirable to also identify the location where the abnormality has occurred. For example, if the maximum deflection becomes a large value that exceeds the allowable value, it can be determined that an abnormality has occurred in the bridge (bridge girder). In addition, multiple sensors 18 ｉ When the rate of change of the tilt angle included in some of the sensor data exceeds a predetermined threshold value based on the monitoring result of the individual sensor data, the sensor 18 outputs the sensor data. ｉ It is possible to determine that an abnormality has occurred near the measurement point. During or after bridge construction, one or more sensors may be installed on the bridge piers to monitor their condition, and this monitoring information may be used for construction management to prevent accidents, issuing warnings, etc.

[0097] 18 ｉ ...Sensor device (sensor), 50...Hand stretching machine (part of the structure), 51...Connected structure (part of the structure), 53 １...bridge girder (part of the structure), 82...front support device.

Claims

1. The bridge construction process up to the erection of the bridge, The method includes a design step, a step for producing a plurality of components based on the design drawing created in the design step, a temporary assembly step for assembling the produced plurality of components into a completed or partial form of a bridge girder in a factory and inspecting the completed or partial form of the bridge girder, a transportation step for transporting the assembled completed or partial form of the bridge girder to an erection site, and an on-site erection step for erecting the bridge at the erection site, A bridge construction process in which, in at least some of the above-mentioned multiple steps until the bridge is erected, at least one sensor is used to measure inclination information of a structure including the assembled bridge girder at a predetermined measurement point, and the measurement results are used in at least some of the steps.

2. 2. The bridge manufacturing process according to claim 1, A bridge fabrication process in which the step of fabricating a plurality of members includes at least one of the sub-steps of sizing, marking, cutting, drilling, and assembling / welding.

3. 3. The bridge manufacturing process according to claim 1 or 2, A bridge manufacturing process in which the pre-assembly step includes obtaining shape information of at least some of the components.

4. 3. The bridge manufacturing process according to claim 1 or 2, A bridge construction process in which, in at least some of the steps, multiple sensors are used to measure inclination information of the structure at multiple measurement points, and shape information of the structure is obtained using the measurement results of the inclination information.

5. 5. The bridge manufacturing process according to claim 4, A bridge construction process in which at least some of the steps include the temporary assembly step, and camber information of the bridge girder is obtained as the shape information in the temporary assembly step.

6. In the bridge manufacturing process according to claim 1 or 2, A bridge manufacturing process, wherein at least some of the steps include the on-site erection step.

7. 7. The bridge manufacturing process according to claim 6, A bridge construction process that controls jacks supporting the structure during construction based on the measurement results.

8. 5. The bridge manufacturing process according to claim 4, At least some of the steps include the on-site erection step, in which a launching method is adopted as the erection method, and shape information of the structure is obtained using measurement results of positional information at the multiple measurement points when launching the structure.

9. 9. The bridge manufacturing process according to claim 8, In the on-site erection step, a bridge construction process is performed in which the relative height between the front end of the structure and the upper surface of the front support device is adjusted based on the obtained shape information of the structure while the structure is approaching the front support device located in front of the sending direction when the structure is sent out.

10. 9. The bridge manufacturing process according to claim 8, In the on-site erection step, a hand-stretching machine method is adopted as the launching method, and the shape of the hand-stretching machine, which is part of the structure, is determined using the measurement results of positional information at the multiple measurement points when launching the structure.

11. 11. The bridge manufacturing process according to claim 10, In the on-site installation step, a change in shape over time due to the weight of the hand-stretching machine is monitored based on the measurement results of the multiple sensors until the hand-stretching machine is finished being sent out; A bridge construction process that corrects for shape changes over time caused by the hand stretching machine's own weight based on the results of the monitoring.

12. In the bridge manufacturing process according to any one of claims 8 to 11, A bridge construction process that uses the output of the sensor to generate an alarm at least during the on-site erection step.

13. A monitoring method for monitoring changes over time in a bridge girder of a bridge, comprising: A monitoring method that includes monitoring changes in the shape of a bridge girder over time by repeatedly acquiring sensor data including inclination information output from sensors that measure inclination information of the bridge girder at each measurement point using a plurality of sensors arranged two-dimensionally on the bridge girder, and calculating the shape of the bridge girder using the acquired sensor data.

14. 14. The monitoring method according to claim 13, A monitoring method for restricting traffic volume on the bridge girder if an unexpected change in shape occurs in the bridge girder based on the results of the monitoring.

15. 14. The monitoring method according to claim 13, A monitoring method in which, based on the monitoring results of individual sensor data from multiple sensors, if the rate of inclination change contained in some of the sensor data exceeds a predetermined threshold, it is determined that an abnormality has occurred near the measurement point of the sensor that outputs that portion of the sensor data.

16. 1. A method of constructing a bridge, comprising: Producing a bridge girder for the bridge; Transporting the fabricated bridge girder to an erection site; Installing the bridge girder on a bridge pier at the erection site; A construction method in which inclination information of the bridge girder is measured by a plurality of sensors attached to a plurality of measurement points of the bridge girder installed on the bridge pier, and the inclination information, or shape information of the bridge girder calculated from the inclination information, is used in installing the bridge girder.

17. 17. The construction method according to claim 16, The bridge girder is composed of a plurality of components, and the construction method includes assembling and inspecting at least a portion of the plurality of components that are each produced prior to the transportation, and during the inspection, the sensor measures inclination information of the assembled bridge girder.