JP4954315B2 - Abnormality detection method for expansion joints for bridges - Google Patents

Description

  The present invention relates to an abnormality detection method for an expansion joint for a bridge installed on, for example, a bridge on an automobile road.

  In a bridge on an expressway, the gap between the members is separated to allow displacement due to temperature changes and earthquakes of each member connected to the connection between the floor slabs and the connection between the floor slab and the abutment. Is provided. An expansion joint that can be expanded and contracted in accordance with the displacement of the member provided with the clearance is disposed at a position where the road surface intersects the clearance between the bridges, and a vehicle or a person is allowed to pass over the expansion joint.

  This type of expansion joint has a material or structure that can be expanded and contracted, and further receives a load repeatedly from a vehicle passing through the road surface, so that the degree of progress of deterioration is faster than other members of the bridge. The deterioration of the expansion joint causes noise accompanying traveling of the vehicle and affects the safety of traveling of the vehicle. Therefore, it is necessary to inspect the expansion joint at a relatively high frequency.

  Conventionally, as an inspection method of expansion joints for bridges, inspectors feel the soundness of expansion joints based on the sounds and vibrations experienced by inspectors riding on patrol vehicles and traveling on roads. Judgment. When the abnormality of the expansion joint is suspected due to the sounds and vibrations experienced, the patrol vehicle is stopped, the inspector approaches the expansion joint, and a contact inspection is performed to detect the abnormality by visual observation or listening to hammering sound. Since the determination made based on the sound and vibration felt by the inspector is based on the skill based on the experience of the inspector, the stability and efficiency of the inspection may be reduced. In addition, it takes time and labor to transfer skills to a new inspector, and there is a problem that chronic insufficiency of inspectors and costs for securing and educating inspectors increase.

  Such a problem of inspection work also exists for other structures related to the road. For example, when inspecting the water permeability of pavement, work efficiency is poor because an inspector goes on the target road surface to perform the on-site water permeability test, and vehicle traffic regulations are required during the on-site water permeability test. Road traffic will be affected. For such a problem, recently, while running on an inspection vehicle, an inspection sound was emitted toward the pavement surface, and the reflected sound of this inspection sound on the pavement surface was recorded. A method for detecting the water permeability of pavement based on attenuation characteristics has been proposed (see, for example, Patent Document 1). According to this method, since the water permeability of the pavement can be detected while traveling on the pavement to be inspected, improvement in inspection work efficiency is expected.

JP-A-6-138103

  However, an abnormality of the expansion joint for bridge cannot be detected based on the attenuation characteristic between the inspection sound and the reflected sound.

  Accordingly, an object of the present invention is to detect an abnormality of a bridge expansion joint based on information collected by a traveling vehicle with relatively high accuracy, and to improve the inspection work efficiency and reduce the cost. An object of the present invention is to provide an abnormality detection method.

  In order to solve the above-described problems, the abnormality detection method for a bridge expansion joint according to the present invention includes a vehicle running sound collected inside the vehicle and a vehicle outside the vehicle when the traveling vehicle passes the installation position of the bridge expansion joint. Vehicle exterior sound is recorded, and the abnormality of the above-mentioned bridge expansion joint is judged based on the judgment value obtained by the product of the sound pressure value of the recorded vehicle interior sound and the sound pressure value of the vehicle exterior sound. It is characterized by.

  It is an object of the present invention to reproduce a determination made based on sound and vibration when an inspector passes a bridge expansion joint on a patrol vehicle by a quantitative method. The inspector's judgment was made while traveling through an abnormal expansion joint for bridges, and in-vehicle running sound and out-of-vehicle running sound were recorded. If the judgment value obtained by analyzing the recorded data by various methods and comparing with the judgment by the inspector and using the product of the sound pressure value of the in-vehicle running sound and the sound pressure value of the outside running sound, We found that it was possible to determine the abnormality of expansion joints for bridges with the same accuracy as that determined by JIS. The present invention has been made based on such knowledge.

  According to the above configuration, when the traveling vehicle passes the installation position of the expansion joint for the bridge, the in-vehicle traveling sound and the outside traveling sound are recorded, and the sound pressure value of the recorded in-vehicle traveling sound and the sound pressure of the outside traveling sound are recorded. A judgment value is obtained by product with the value. Since the abnormality of the expansion joint for bridge is determined based on this determination value, the abnormality of the expansion joint for bridge can be detected more stably and efficiently than the determination based on the experience of the inspector.

  An abnormality detection method for an expansion joint for a bridge according to an embodiment includes the sound pressure value of the in-vehicle traveling sound and the sound pressure value of the outside traveling sound traveling through an abnormal bridge expansion joint and a normal bridge expansion joint. Frequencies that are identified based on in-vehicle running sound and out-of-vehicle running sound that are recorded in different ways, and a spectrum that appears differently when running through an abnormal bridge expansion joint and when running through a normal bridge expansion joint. The sound pressure value of the band.

  According to the above embodiment, the vehicle interior traveling sound and the vehicle exterior traveling sound are recorded in advance by traveling through an abnormal bridge expansion joint and a normal bridge expansion joint. Based on these in-vehicle running sound and out-of-vehicle running sound, the frequency band in which a different spectrum appears between when traveling on an abnormal bridge expansion joint and when traveling on a normal bridge expansion joint is identified. . With respect to the specified frequency band, the abnormality of the expansion joint for bridge can be determined based on the determination value obtained by the product of the sound pressure value of the traveling sound inside the vehicle and the sound pressure value of the traveling sound outside the vehicle.

The abnormality detection method for an expansion joint for a bridge according to an embodiment is such that the sound pressure value is a partial overall value in the frequency band of the outside running sound and the inside running sound,
When the product of the sound pressure value of the outside running sound and the sound pressure value of the inside running sound exceeds a predetermined threshold, it is determined that the bridge expansion joint is abnormal.

  According to the above embodiment, the partial overall value in the frequency band of the outside running sound and the inside running sound is obtained, and when the product of the outside overall sound and the partial overall value of the inside running sound exceeds a predetermined threshold value, this threshold value is obtained. It can be determined that the expansion joint for the bridge corresponding to the traveling sound exceeding the range is abnormal.

  An abnormality detection method for a bridge expansion joint according to an embodiment is such that an abnormality of the bridge expansion joint is caused by damage to a component part constituting the bridge expansion joint, damage to a component fixing tool, and fixing of the component part. At least one of the looseness of the condition.

  According to the above embodiment, based on the in-vehicle traveling sound and the out-of-vehicle traveling sound collected when the traveling vehicle passes through the installation position of the bridge expansion joint, the components constituting the bridge expansion joint are damaged, the component It is possible to determine at least one of the breakage of the fixing tool and the looseness of the fixed state of the component parts.

It is a figure which shows the inspection vehicle used with the abnormality detection method of the expansion joint for bridges as embodiment of this invention. It is a top view which shows the example of the expansion joint for bridges to which the abnormality detection method of embodiment is applied. It is sectional drawing of the expansion joint for bridges of FIG. 2A. It is a top view which shows the example of the expansion joint for other bridges. It is sectional drawing of the expansion joint for bridges of FIG. 3A. It is the figure which piled up and showed the result of the frequency analysis of the in-vehicle running sound in an abnormal standard joint and a normal standard joint. It is a figure which shows the fluctuation | variation of the sound pressure value of the in-vehicle running sound corresponding to the specified frequency band. It is a figure which shows the fluctuation | variation of the sound pressure value of the running sound outside a vehicle corresponding to the specified frequency band. It is a figure which shows the fluctuation | variation of the product of the sound pressure value of a running sound inside a vehicle and a running sound outside a vehicle.

  Hereinafter, an embodiment of an abnormality detection method for an expansion joint for a bridge according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram showing an inspection vehicle used as a traveling vehicle in order to record in-vehicle traveling sound and outside-vehicle traveling sound in the present embodiment. The inspection vehicle 1 includes an in-vehicle microphone 2 that collects in-vehicle traveling sound, an out-of-vehicle microphone 3 that collects out-of-vehicle traveling sound, an in-vehicle microphone 2 and an out-of-vehicle microphone 3 on a four-wheel drive type vehicle body having a prime mover. A recording device 4 for storing the collected sound is mounted. The recording device 4 stores the sound collected by the vehicle interior microphone 2 and the vehicle exterior microphone 3 in association with the collection time. The recording device 4 may store the recording position detected by GPS (Global Positioning System) or the like in addition to the recording time of the running sound.

  2A is a plan view showing an example of an expansion joint whose abnormality is determined by the abnormality detection method of the present embodiment, and FIG. 2B is a cross-sectional view of the expansion joint of FIG. 2A. In the expansion joint 10, a comb-like face plate 11 made of steel is fixed and installed at the ends of two floor slabs 7 and 7 installed with a gap B. The face plate 11 is formed by forming a plate-like steel material into a comb shape having a plate-like portion 11A and a tooth-like portion 11B, and the plate-like portion 11A is bolts 13, 13,.・ It is fixed with. The two faceplates 11 fixed to the two floor slabs 7 and 7 are engaged with each other with toothed portions 11B. Below the face plate 11, a resin sealing member 14 that stops water, a resin elastic member 15 that reduces impact, and a lower part so as to fill a gap B between the two floor slabs 7 and 7. A rubber water-stopping member 16 that is attached in a convexly bent state and stops water is disposed. The expansion joint 10 is provided on the floor slabs 7 and 7 while permitting temperature changes of the floor slabs 7 and displacements associated with earthquakes within a range in which the toothed portions 11B of the two face plates 11 are kept engaged. The vehicle traveling on the road surface can be passed. In addition, although this expansion joint 10 connects between the two floor slabs 7 and 7, the expansion joint which connects a floor slab and an abutment may be sufficient. The expansion joint 10 includes a seal member 14, an elastic member 15, and a water stop member 16 for water stop and shock mitigation, but various water stop or shock mitigation structures using other materials and members are applied. It may be.

  According to the abnormality detection method of the present embodiment, it is possible to detect an abnormality on the expansion joints of other structures based on the traveling sound. As an expansion joint having another structure, there are those shown in the plan view of FIG. 3A and the cross-sectional view of FIG. 3B. In the expansion joint 20, a joint body 21 made of rubber and having a substantially rectangular cross section is fixed to the ends of two floor slabs 7 and 7 installed with a gap B.

  The expansion joint 20 is disposed in a state where steel mounting plates 22 provided on the bottom surfaces of both ends of the joint body 21 are in contact with the bottom surface of the notch formed at the end of the floor slab 7. The expansion joint 20 is fixed to the floor slab 7 with bolts 23 that are inserted from the surface of the joint body 21 and penetrate the mounting plate 22. A core member 24 made of a steel plate is embedded in the surface portion of the joint body 21 of the expansion joint 20 in order to withstand the load when the vehicle travels. By connecting the floor slabs 7 and 7 with the expansion joint 20, it is possible to pass a vehicle traveling on the road surface on the floor slabs 7 and 7 while allowing the temperature changes of the floor slabs 7 and the displacement accompanying the earthquake. . In addition, although this expansion joint 20 connects between the two floor slabs 7, 7, the expansion joint which connects a floor slab and an abutment may be sufficient. In the expansion joint 20, the rubber joint body 21 is fixed to the floor slab 7 with the bolts 23 via the steel mounting plate 22, but other materials and structures may be applied. .

(Recording of running sound)
The inspection vehicle 1 travels on a road where the expansion joint to be inspected exists, and sounds associated with traveling of the inspection vehicle 1 are collected by the in-vehicle microphone 2 and the out-of-vehicle microphone 3. Sounds collected by the in-vehicle microphone 2 and the out-of-vehicle microphone 3 are stored in the recording device 4 in association with the collection time. The sound collected by the in-vehicle microphone 2 and the out-of-vehicle microphone 3 includes sound generated as the wheels of the inspection vehicle 1 get over the expansion joint when passing through the plurality of expansion joints.

(Frequency analysis)
Of the sounds collected as the inspection vehicle 1 travels, frequency analysis is performed on the sound related to the expansion joint that is found to be abnormal and the sound related to the normal expansion joint. Specifically, first, of the expansion joints present on the road on which the inspection vehicle 1 has traveled, the expansion joints that are known to be abnormal (hereinafter referred to as abnormal reference joints) and the normal expansion joints (normal reference joints) are identified. To do. Here, the abnormality of the expansion joint 10 includes damage to the face plate 11, the joint body 21, and the core material 24, damage to the bolt 13 that fixes the face plate 11 and the joint body 21 to the floor slab 7, looseness, and dropout. At least one of the following.

  Subsequently, the frequency analysis of the traveling sound in the identified abnormal reference joint and the frequency analysis of the traveling sound in the normal reference joint are performed based on the sound information stored in the recording device 4.

  FIG. 4 is a diagram in which the results of frequency analysis of in-vehicle traveling sound at the abnormal reference joint and the normal reference joint are overlapped. In FIG. 4, the horizontal axis represents frequency (Hz) and the vertical axis represents sound pressure (Pa). In FIG. 4, among the ten expansion joints from J1 to J10, the expansion joint of J6 is an abnormal reference joint, and the other nine expansion joints are normal reference joints. As can be seen from FIG. 4, the frequency spectrum in the abnormal reference joint is clearly different from the frequency spectrum in the normal reference joint in the range of 500 Hz to 800 Hz. Thereby, 500 Hz or more and 800 Hz or less in which a different spectrum appears is specified as a frequency band which calculates | requires the sound pressure value of in-vehicle running sound.

  Further, although not shown, the frequency analysis of the abnormal reference joint and the normal reference joint is also performed for the running sound outside the vehicle, the frequency band where the different spectrum appears is specified, and the frequency band for obtaining the sound pressure value of the running sound outside the vehicle is set. In the present embodiment, 1.5 kHz or more and 5.0 kHz or less is specified as the frequency band for obtaining the sound pressure value of the running sound outside the vehicle.

  Then, the sound pressure value regarding the specified frequency band is calculated | required about the in-vehicle running sound and the outside running sound of all the sections which the test vehicle 1 recorded. As the sound pressure value, the partial overall value of the sound pressure included in the frequency band is used.

  FIG. 5 is a diagram showing a state where a sound pressure value corresponding to a frequency band of 500 Hz or more and 800 Hz or less of in-vehicle running sound fluctuates in a part of sections. In FIG. 5, the horizontal axis represents time (hour, minute, second), and the vertical axis represents sound pressure value (Pa). In the time axis of FIG. 4, 12:37:52 is the time when the inspection vehicle 1 passes through the abnormal reference joint.

  FIG. 6 is a diagram showing a state where a sound pressure value corresponding to a frequency band of 1.5 kHz or more and 5.0 kHz or less of the running sound outside the vehicle fluctuates for a part of the sections. In FIG. 6, the horizontal axis represents time (hour, minute, second), and the vertical axis represents sound pressure value (Pa). In the time axis of FIG. 6, 12:37:52 is the time when the inspection vehicle 1 passes the abnormal reference joint.

(Judgment)
When the sound pressure value based on the partial overall value in the frequency band is obtained for each of the in-vehicle running sound and the outside running sound, the product of the sound pressure value of the in-vehicle running sound and the sound pressure value of the outside running sound is obtained. FIG. 7 is a diagram showing, along the time axis, determination values obtained by multiplying the sound pressure value of the in-vehicle running sound and the sound pressure value of the outside running sound. In FIG. 7, the horizontal axis represents time (hour, minute, second), and the vertical axis represents the determination value (Pa ² ). In the time axis of FIG. 7, 12:37:52 is the time when the inspection vehicle 1 passes through the abnormal reference joint.

As is apparent from FIG. 7, when the judgment value, which is the product of the sound pressure value of the in-vehicle running sound and the sound pressure value of the outside running sound, exceeds 0.015 (Pa ² ) as a threshold value, The expansion joint in which the sound and the running sound outside the vehicle are recorded can be determined to be abnormal. This determination value is obtained for all sections in which sound is stored in the recording device 4 of the inspection vehicle 1, and whether the determination value corresponding to the expansion joint exceeds the threshold value determines whether the expansion / contraction included in the section is included. The abnormality of the joint can be detected efficiently.

  In the present embodiment, in-vehicle running sound and out-of-vehicle running sound are recorded in the inspection vehicle 1, and an inspector gets on the inspection vehicle 1 to determine abnormality of the expansion joint. An experiment was conducted to compare the judgment based on.

  When this experiment was performed by passing four times through the abnormality reference joint in the inspection vehicle 1, the determination value exceeded the threshold value and the determination result of the inspector became abnormal in the three passes. Therefore, it can be said that the abnormality determination method based on the determination value of the present embodiment can quantitatively perform determination with the same degree of accuracy as the determination based on the experience of the inspector.

  According to the above embodiment, it is possible to quantitatively perform the determination with the same degree of accuracy as the determination based on the skill of the inspector, so that the inspection efficiency of the expansion joint can be increased as compared with the conventional case, and as a result. Can reduce the cost of inspection.

  In the above embodiment, the frequency band for obtaining the partial overall value of the in-vehicle running sound and the outside running sound is set to 500 Hz to 800 Hz and the outside running sound is set to 1.5 kHz to 5.0 kHz. A partial overall value based on the frequency band may be used.

In the above embodiment, the threshold value of the judgment value, which is the product of the sound pressure value represented by the partial overall value of the in-vehicle running sound and the sound pressure value represented by the partial overall value of the outside running sound, is 0.015 (Pa ^Although set to ² ), the threshold value may be set to another value depending on the form of abnormality of the expansion joint to be detected.

  Moreover, in the said embodiment, although the expansion joint of test object was the expansion joint 10 which has the steel faceplate 11, and the expansion joint 20 which has the rubber joint main body 21, it is about the expansion joint of another structure. Also, an abnormality can be detected based on the running sound.

  Moreover, in the said embodiment, with the running sound recorded inside and outside the vehicle, the acceleration measured inside and outside the vehicle may be collected together and used for abnormality determination of the expansion joint.

  In addition, the inspection vehicle 1 is configured by mounting the in-vehicle microphone 2, the out-of-vehicle microphone 3, and the recording device 4 on a four-wheel drive type vehicle main body having a prime mover. In-vehicle microphone 2 and external microphone 3 may be mounted.

  Moreover, although the example which detects the abnormality of the expansion joint of the bridge of an expressway was demonstrated in the said embodiment, the abnormality detection method of this invention is applicable also to the expansion joint of another bridge.

DESCRIPTION OF SYMBOLS 1 Inspection vehicle 2 In-car microphone 3 Outside-car microphone 4 Recording device

Claims (4)

  When the traveling vehicle passes the installation position of the expansion joint for bridges, it records the in-vehicle traveling sound collected inside the vehicle and the outside traveling sound collected outside the vehicle, and the sound pressure value of the recorded in-vehicle traveling sound and An abnormality detection method for a bridge expansion joint, wherein the abnormality of the bridge expansion joint is determined based on a determination value obtained by a product of a sound pressure value of a running sound outside the vehicle. In the abnormality detection method of the expansion joint for bridges of Claim 1,
The sound pressure value of the in-vehicle running sound and the sound pressure value of the outside running sound are based on the in-vehicle running sound and the out-of-vehicle running sound recorded by running through an abnormal bridge expansion joint and a normal bridge expansion joint. The sound pressure value for the bridge is characterized by the frequency band in which a different spectrum appears between when traveling through an abnormal expansion joint for a bridge and when traveling through a normal expansion joint for a bridge. Abnormal detection method for expansion joints. In the abnormality detection method of the expansion joint for bridges of Claim 2,
The sound pressure value is a partial overall value in the frequency band of the outside running sound and the inside running sound,
When the product of the sound pressure value of the outside running sound and the sound pressure value of the inside running sound exceeds a predetermined threshold, it is determined that the bridge expansion joint is abnormal. Anomaly detection method. In the abnormality detection method of the expansion joint for bridges of Claim 1,
The abnormality of the expansion joint for a bridge is at least one of damage to a component constituting the expansion joint for a bridge, damage to a fixture of the component, and looseness of a fixed state of the component. An abnormality detection method for expansion joints for bridges.