JP6050152B2 - Non-contact evaluation method for damage to bearing parts of railway bridges - Google Patents

Description

  The present invention relates to a non-contact evaluation method for damage to a bearing portion of a railway bridge.

  If damage or abnormality occurs in the bridge support, the support state of the girder may become unstable and vibration may occur in the girder. In addition, unexpected displacement and stress may occur in the bridge member, which may cause damage and cracking of the member. When a certain support part deforms, the girder supported by the support part becomes a three-point support state, and the girder flutters, increasing the displacement of the girder and causing further damage to the support part and other members. For this reason, the maintenance of the bearing is very important, but the current inspection is mainly performed by visual inspection, and the mounting position of the bearing is often high, improving the safety of the inspection. And quantitative evaluation methods are required.

JP 2008-281422 A

  As mentioned above, inspections of railway bridge bearings are mainly carried out by visual inspection, but the bearings are often installed in high places or places that are difficult to see. bad. Furthermore, there has been a problem that the degree of damage to the bearing cannot be quantitatively evaluated.

  Note that the inventors of the present application have already proposed a non-contact measurement system for vibration characteristics of a structure (see Patent Document 1).

  In view of the above situation, the present invention performs inspection of a girder in the vicinity of a railway bridge support using a non-contact sensor, and enables safe, efficient, and quantitative measurement. The purpose is to provide an evaluation method.

In order to achieve the above object, the present invention provides
[1] Non-contact evaluation method for damage to railway bridge supports by quantitatively assessing damage to railway bridge supports by measuring vibrations and displacements of girders near railway bridge supports using non-contact sensors. Since the vibration of the bearing part of a damaged railway bridge increases, the degree of damage of the railway bridge support part is evaluated by comparing the measured amplitude and spectrum of each vibration using an analysis device . A non-contact evaluation method for damage to a bearing portion, wherein when one non-contact sensor is used, the non-contact sensor main body is attached to the pier, and in that state, the non-contact sensor main body is attached to the pier support portion. It is characterized by measuring vibration at the end of the near beam .

[ 2 ] In the non-contact evaluation method for damage to a bearing portion of a railway bridge described in [1] above , assuming that vibration in the compression direction of the pier is negligible, a vibration meter attached to the non-contact sensor body is used to By measuring the vibration and comparing the vibration with the vibration at the end of the girder, it is possible to detect a bearing portion that is damaged and causes a greater vibration than the pier .

[ 3 ] In the non-contact evaluation method for damage to a bearing portion of a railway bridge described in [1] above, if there is almost no change in the speed and load of the train crossing the bridge, one railway at the time of passing the train It is characterized by measuring and recording the vibration of the girder near the support part of the bridge and the vibration of the girder near the support part of different railway bridges by different trains and comparing them with one non-contact sensor .

[ 4 ] In the non-contact evaluation method for damage to a bearing part of a railway bridge described in [3] above , the vibration measurement result is compared by an analysis device from the recorded vibration data of the girder near each bearing part. It is characterized by evaluating damage .

[ 5 ] If one of the support parts of the girder is damaged, the girder will be fluttered in a three-point support state. The deflection of the girder at the time of passing the train is measured by the contact sensor, and the time history of this deflection is recorded. After passing through the train, the vibration of the girder is attenuated. In the non-contact evaluation method for damage to the bearing parts of railway bridges, which examines the presence or absence of three-point support by determining the vibration attenuation of the girder after passing. In the case of multi-main girder bridges, two or more non-contact sensors If it can be used, first determine one reference bearing, and simultaneously measure the vibration of the girder near the bearing and the vibration of the girder near the measurement target, and change the reference bearing. Without changing the support part to be measured in order, Come, and evaluating the damage of the bearing portion by gradually normalized in order of measurement results near bearing as a reference the results.

  According to the present invention, it is possible to safely, efficiently, and quantitatively evaluate the degree of damage even for a bearing portion of a railway bridge at a high place or a place that is difficult to check.

It is a figure which shows the non-contact evaluation procedure of the support part of a railway bridge which shows the Example of this invention. It is a schematic diagram of the measurement at the time of using two non-contact sensors which show the Example of this invention. It is a schematic diagram of the measurement at the time of using one non-contact sensor which shows the Example of this invention. It is a schematic diagram which shows the measuring method in the case of confirming the presence or absence of the three-point support state which shows the Example of this invention easily with one sensor. It is a schematic diagram which shows the measuring method in case there exist multiple main girders seen from the bridge-axis direction which shows the Example of this invention.

The non-contact evaluation method for damage to a bearing part of a railway bridge according to the present invention quantitatively evaluates damage to the support part of a railway bridge by measuring vibration and displacement of a girder near the support part of the railway bridge with a non-contact sensor. In the non-contact evaluation method for damage to railway bridge bearings, the vibrations at the damaged railway bridge bearing parts increase. Therefore, by comparing the measured amplitude and spectrum of each vibration with an analyzer, the railway bridge This is a non-contact evaluation method for damage to a bearing part of a railway bridge that evaluates the degree of damage of the bearing part of the railway. When one of the non-contact sensors is used, the non-contact sensor body is attached to the pier, Vibration measurement is performed at the end of the spar close to the support portion of the pier to which the non-contact sensor body is attached .

  Hereinafter, embodiments of the present invention will be described in detail.

  Here, steel bearings are the main target of the railway bridges. The non-contact evaluation procedure is performed according to the flowchart shown in FIG. As the non-contact sensor, a non-contact sensor such as a laser Doppler velocimeter (LDV) is used.

  (1) A girder near the support portion of the railway bridge is inspected by a non-contact sensor (step S1).

  (2) A simple inspection of the three-point support state of the support portion of the railway bridge is performed (step S2).

  (3) Deflection is measured when the train passes (step S3).

  (4) The measurement data is recorded in the recording device (step S4).

  (5) A logarithmic decay rate is obtained by an analyzer (step S5).

    If there is an abnormality in step S5, the process proceeds to a detailed inspection, and if there is no abnormality, the inspection is terminated.

  (6) An inspection is performed in the detailed case where an inspection of the girder near the individual bearings is necessary (step S6).

  (7) How many non-contact sensors are there (step S7)?

  (8) One non-contact sensor is used (step S8).

  (9) Is the speed and load of the train passing through the railway bridge constant (step S9)?

  (10) When the train speed and load are constant in step S9, vibration measurement of the digits near the support portion is sequentially performed (step S10).

  (11) The measurement data is recorded in the recording device (step S11).

  (12) On the other hand, when the speed and load of the train are not constant, the non-contact sensor is fixed to the pier, and the vibration of the girder near the support portion is measured in that state (step S12), and then step S11 is entered. .

  (13) On the other hand, when two or more non-contact sensors are used in step S7 (step S13).

  (14) The vibration measurement in the vicinity of the support portion of the same girder is performed by two non-contact sensors (step S14), and then step S11 is entered.

  (15) Next, the measurement results are compared by the analyzer, the degree of damage is evaluated (step S15), and the inspection is terminated (step S16).

  Hereinafter, it demonstrates in detail for every aspect of a sensor.

[1] When there are a plurality of non-contact sensors FIG. 2 is a schematic diagram of measurement when two non-contact sensors according to an embodiment of the present invention are used, and FIG. 2 (a) is a side view of a railway bridge. FIG. 2 (b) is a plan view of a railway bridge, and FIG. 2 (c) is a diagram showing an image of spectrum comparison of measurement results.

  In these drawings, 1 is a bridge pier, 2 is a bearing portion of a railway bridge disposed on the pier 1, and includes fixed bearing portions 2A and 2B and movable bearing portions 2C and 2D. 3 is a digit, 4 is a non-contact sensor, and comprises two non-contact sensors 4A and 4B. These two non-contact sensors 4A and 4B are connected to the analysis device 5. That is, as shown in FIGS. 2 (a) and 2 (b), the measurement points on the girder 3 near the support portion 2 of the railway bridge provided on the same pier 1 and girder 3 by the non-contact sensors 4A and 4B, respectively. 6A and 6B vibration measurements are performed. Vibration measurement is performed when the train passes, and peak values Sp1 to Sp4 of the Fourier spectrum of vibration are obtained from the recorded data using the analysis device 5 and compared. This operation is performed on the measurement points 6A and 6B on the girders 3 in the vicinity of all the support portions 2A, 2B, 2C, and 2D provided in the same girders 3, and the analysis results are compared to cause damage. The bearing part 2 is detected and its degree is evaluated. An image of the measurement result is shown in FIG. The peak value (Sp4 in the figure) of the damaged support is higher than the peak value (Sp1 to Sp3 in the figure) of the spectrum that is not damaged as shown in FIG. The degree of damage of the support part 2 of the railway bridge can be evaluated by the magnitude of the peak of the spectrum.

[2] When only one non-contact sensor can be used FIG. 3 is a schematic diagram of measurement when one non-contact sensor according to the embodiment of the present invention is used, and FIG. A side view and FIG.3 (b) are figures which show the image of the comparison of the spectrum of a measurement result.

  When only one non-contact sensor can be used, the non-contact sensor 13 is fixed to the pier 11 as shown in FIG. 3 (a), and in this state, the end of the beam 15 near the support portion 12 of the railway bridge is used. Vibration measurement at the time of passing the train at the measurement point 17 on the girder 15 is performed. The non-contact sensor 13 itself is also provided with a vibration measuring device 14. The vibration measuring device 14 is used to measure the vibration of the pier 11 itself to vibrate the measurement point 17 on the girder 15 near the support portion 12 of the railway bridge. Compare with The pier 11 is generally high in rigidity, and the compression of the pier 11 in the vertical direction is negligible, and there is a large difference between the vibration at the attachment position of the non-contact sensor 13 on the pier 11 and the vibration at the attachment position of the support portion 12 of the railway bridge. Not assumed. Therefore, when a large vibration is generated in the girder 15 near the mounting support 12 of the railway bridge as compared with the vibration of the pier 11, the vibration is considered to be due to the damage of the support 12 of the railway bridge. As shown in FIG. 3B, the spectrum of vibration of the bridge pier 11 and vibration of the girder 15 near the support portion 12 of the railway bridge is obtained by the analysis device 16 with respect to the measured vibration. Divide the peak value of the spectrum of the vibration of the digit 15 (Sp1 and Sp1 ′ in the figure) by the peak value of the spectrum of the vibration of the pier 11 (Sp0 in the figure), and if the value is close to 1, there is no damage. It is judged that the degree of damage increases as the value of increases.

[3] Case where the presence / absence of the three-point support state is simply confirmed by one sensor The case where the presence / absence of the three-point support state is simply confirmed by one non-contact sensor 21 is shown in FIG. Thus, the deflection measurement of the digit 24 at the time of train passing is performed using one non-contact sensor 21. 22 is a bridge pier, and 23 is a bearing part of a railway bridge. As shown in FIG. 4B, the vibration of the girder 24 after passing through the train is attenuated when the railway bridge support 23 is damaged and is supported at three points (step S2). The logarithmic decay rate of the vibration after passing through the train is obtained (step S5), and if the value is low, it can be determined that there is a possibility of damage to the support portion 23 of the railway bridge.

[4] When there are a plurality of main beams As shown in FIG. 5, when there are a plurality of main beams 31, two or more non-contact sensors 32 are prepared and inspected. Decide one reference base and measure the vibration of the girder near the base and the girder near the target girder when the train passes. Without changing the reference support part, the measurement target support parts are sequentially changed, and the peak of the Fourier spectrum of the vibration of the girder near each support part is obtained. After that, normalize by dividing the peak of vibration spectrum of each digit near the bearing part to be measured by the peak of vibration spectrum of the digit near the standard bearing part, and compare the values. Determine the presence and extent of damage.

  In addition, this invention is not limited to the said Example, Based on the meaning of this invention, a various deformation | transformation is possible and these are not excluded from the scope of the present invention.

  The non-contact evaluation method for damage to a bearing part of a railway bridge according to the present invention is a method for inspecting a girder near a support part of a railway bridge using a non-contact sensor, and enables safe, efficient and quantitative measurement of the railway bridge. It can be used as a non-contact evaluation method for bearing damage.

1,11,22 Bridge piers 2,2A, 2B, 2C, 2D, 12,23 Railroad bridge bearings 2a, 2b Fixed bearings 2c, 2d Movable bearings 3, 15, 24 Digits 4, 4A, 4B, 13, 21, 32 Non-contact sensor 5, 16 Analyzing device 6, 6A, 6B, 17 Measuring point on beam near bearing part 14 Vibration measuring device 31 Main beam

Claims (5)

In a non-contact evaluation method for damage to railway bridge bearings, damage and damage to railway bridge bearings are quantitatively evaluated by measuring vibration and displacement of the girder near the railway bridge bearings with a non-contact sensor. Since the vibration at the bearing part of the received railway bridge increases, the damage of the railway bridge support part is evaluated by comparing the measured amplitude and spectrum of each vibration with an analyzer. In the non-contact evaluation method, when one non-contact sensor is used, the non-contact sensor main body is attached to the pier, and in this state, the girder end close to the support portion of the pier to which the non-contact sensor main body is attached. Non-contact evaluation method for damage to bearing parts of railway bridges, characterized by measuring the vibration of the parts . 2. The non-contact evaluation method for damage to a bearing part of a railway bridge according to claim 1, wherein vibration of the bridge pier is assumed to be negligible and vibration of the bridge pier is measured with a vibration meter attached to a non-contact sensor body. By comparing the vibration with the vibration at the end of the girder, the damage to the bearing part of the railway bridge, which is damaged and detects the bearing part that causes a greater vibration than the pier, is detected. Non-contact evaluation method. 2. A non-contact evaluation method for damage to a bearing part of a railway bridge according to claim 1, wherein if there is almost no change in the speed and load of the train crossing the bridge, the bearing part of one railway bridge when the train passes. The damage of railway bridge bearings is characterized by measuring and recording the vibration of nearby girders and the vibration of girders near different railway bridge bearings by different trains using a single non-contact sensor and comparing them . Non-contact evaluation method. 4. A non-contact evaluation method for damage to a bearing part of a railway bridge according to claim 3, wherein the vibration measurement result is compared by an analysis device from the recorded vibration data of the girder near each bearing part to evaluate the damage of the bearing part. A non-contact evaluation method for damage to bearing parts of railway bridges. If one of the support parts of the girder is damaged, the girder will be fluttered with a three-point support, so if you want to easily check for such flutter, use a non-contact sensor. Measure the deflection of the girder when passing through the train and record the time history of the deflection. After passing the train, the vibration of the girder is attenuated. In the non-contact evaluation method for damage to the bearing parts of railway bridges, which examines the presence or absence of three-point support by determining the damping of girder vibrations. In the case of multi-main girder bridges, two or more non-contact sensors can be used. If there is, first determine one reference bearing, and simultaneously measure the vibration of the girder near the bearing and the vibration of the girder near the measurement target, and measure without changing the reference bearing. Change the target support part in order and measure the vibration. Non-contact method for evaluating bearing damage railway bridges and evaluating damage of the bearing portion by fruit going normalized digits of the measurement results near bearing as a reference.

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