JP2021070945A - Internal defect detection display method for highway concrete floor slabs using perspectives and system for the same - Google Patents

Abstract

To provide an internal defect detection display method for highway concrete floor slabs using perspectives and system for the same that can efficiently detect an internal defect of a highway concrete floor slab and display it in an easy-to-see manner using perspectives.SOLUTION: An internal defect detection system comprises: an electromagnetic wave radar device 10; an arithmetic unit 11 that acquires internal defects of a concrete floor slab 20 as three-dimensional data using an electromagnetic wave propagation time of the electromagnetic wave radar; a GPS receiver 12 that locates the internal defects; and a CIM display device 13 that superimposes the three-dimensional data of the internal defects onto a photographic image of a highway and displays it as a CIM. While traveling on the highway, the concrete floor slab 20 is continuously searched by the electromagnetic wave radar to acquire internal defects 21 of the concrete floor slab 20 as three-dimensional data. The positions of the internal defects 21 are identified using GPS and the three-dimensional data of the internal defects is superimposed on the photographic image of the highway and displayed as a CIM.SELECTED DRAWING: Figure 1

Description

The present invention is a method for detecting and displaying internal defects in a concrete slab of an expressway using a perspective view that can identify the position and display the internal defects of the concrete slab of the expressway in an easy-to-understand manner by creating a perspective view thereof. It's about the system.

The concrete deck of a highway is an important member that directly supports the load of a car, and its damage directly leads to an accident. In addition, repairing damaged parts causes social loss such as traffic restrictions, so it is necessary to detect abnormalities inside the concrete floor slab and take measures in advance before damage occurs.

Therefore, as shown in Patent Document 1, a method of detecting an internal defect of a concrete floor slab using thermography has been proposed. In this method, a sensor such as an infrared camera is placed on the underside of the concrete slab, and the presence or absence of internal defects is detected by utilizing the fact that the temperature distribution of the concrete slab that follows temperature changes differs depending on the internal deformation of the concrete slab. The method.

However, with this method, only the relatively shallow part of the lower surface of the concrete slab can be inspected, and the part close to the upper surface of the concrete slab cannot be inspected. In addition, when the existence of a defect is found inside, the position is only recorded as data. Therefore, it is necessary to specify the position from the recorded data to confirm the progress of the internal defect after that. There was a problem that the confirmation work was not easy.

Japanese Unexamined Patent Publication No. 2003-247964

Therefore, an object of the present invention is to solve the above-mentioned conventional problems, to efficiently detect internal defects in a concrete floor slab of an expressway, and to create a perspective view so that the position can be specified and displayed in an easy-to-see manner. It is to provide the internal defect detection display method and the system of the highway concrete slab using a figure.

The method for detecting and displaying internal defects in a highway concrete slab using a perspective view of the present invention, which was made to solve the above problems, continuously searches the concrete slab with an electromagnetic wave radar while traveling on an expressway. Then, the internal defects of the concrete floor slab are acquired and modeled as three-dimensional data, and the position data on the highway where the internal defects are detected are acquired by using GPS, and the three-dimensional model of the internal defects is obtained. It is characterized in that the position data is superimposed on a photographic image of the same highway and displayed in CIM. By combining with the photographic image obtained while driving on the highway, the position can be visually specified so that the inside of the concrete slab can be seen through, and the photographic image of the highway can be made into a movie. It can also be combined with point group 3D data such as a mapping system.

In addition, the detection and display system for internal defects of the highway concrete slab using the perspective view of the present invention, which was made to solve the above problems, is mounted on a vehicle and travels on the highway while displaying the concrete slab. An electromagnetic wave radar device that continuously explores, a GPS receiver that is mounted on the same vehicle and acquires position data on the highway where internal defects are detected, and a concrete floor using the electromagnetic wave propagation time of the electromagnetic wave radar. An arithmetic device that acquires the internal defects of the plate as 3D data and a 3D model of the internal defects are created from the 3D data, and the 3D model of the internal defects is superimposed on a photographic image of a highway having the same position data. It is characterized by being provided with a CIM display device for displaying CIM.

According to the present invention, while the electromagnetic wave radar device is mounted on a vehicle and traveled on a highway, the shape of an internal defect of a concrete deck is acquired as three-dimensional data, and the position on the highway where the internal defect is detected is detected. Can also be specified using a GPS receiver. Then, a 3D model of the internal defect is created from the obtained 3D data of the internal defect using computer graphics, and the position data is superimposed on the photographic image of the same highway and displayed in CIM. It is possible to display at what depth of the concrete floor slab the internal defects are very easy to see. In addition, by conducting exploration with an electromagnetic wave radar device at intervals, it is possible to easily grasp the progress of internal defects, and there is an advantage that information for maintenance of an expressway can be intuitively obtained. Further, since it is not necessary to drive the vehicle equipped with the electromagnetic wave radar device at a low speed, it does not interfere with the traveling of other vehicles.

It is a block diagram of the system of this invention. It is a detection principle diagram of an internal defect by an electromagnetic wave radar device. It is a photographic image of a highway. It is an image in which an internal defect is superimposed on a photographic image of an expressway and displayed by CIM.

An embodiment of the present invention will be described below.
FIG. 1 is a configuration diagram of the system of the present invention, in which 10 is an electromagnetic wave radar device, 11 is an arithmetic device, 12 is a GPS receiving device, 13 is a CIM display device, and 14 is a vehicle. The electromagnetic wave radar device 10 utilizes the property that electromagnetic waves in the microwave band (radio wave band having a wavelength of 1 mm to 1 m) travel straight through the medium at a constant speed and are reflected on the surface of an object having electrical properties different from those of the medium. It is a device that detects the distance and position to an object.

The electromagnetic wave radar device 10 used in the present invention is an in-vehicle radar device that can be mounted on a vehicle 14, and includes a transmitting antenna 15, a receiving antenna 16, a control calculation unit 17, a display unit 18, and the like. As shown in FIG. 2, the electromagnetic wave radar device 10 radiates electromagnetic waves from the transmitting antenna 15 to the concrete floor slab 20 of the highway while traveling on the highway. Since the traveling speed of the vehicle 14 can be 60 to 80 km / h, it does not interfere with the traveling of other vehicles. The concrete slab 20 of the highway is made of concrete, and if there is an object or cavity having different electrical properties from the concrete inside, the electromagnetic wave is reflected at the interface with the concrete, and the receiving antenna 16 receives this reflected wave. To receive.

As shown in FIG. 2, when the concrete deck 20 has an internal defect 21 having an electrical property different from that of concrete, the electromagnetic wave propagation time T detected by the electromagnetic wave radar device 10 mounted on the traveling vehicle 14 is internal. _{It is a long T 1} when it is away from the defect 21 _{, but it becomes the shortest T 2} when the electromagnetic wave radar device 10 comes directly above the internal defect 21, and then it becomes long again. The position and depth of the internal defect 21 can be detected by utilizing this phenomenon.

_{The distance D 2} shown in FIG. 2 is called the cover thickness and is expressed by the equation _{D 2} = T _{2 × V / 2.} Here, T ₂ is the time until the electromagnetic wave from the antenna 15 is received by the receiving antenna 16, and V is the velocity of the electromagnetic wave in the concrete. The speed of electromagnetic waves 300,000 km / sec in air, i.e. is a ^{3 × 10 8 (m / s} ), when traveling through a medium other than air, such as ^{concrete, V = 3 × 10 8 /} √ε ( m / s).

ε is the relative permittivity of concrete, which is 4 to 6 for dry concrete, 6 to 12 for standard concrete, and 8 to 20 for wet concrete. In this way, the relative permittivity ε of concrete is greatly affected by the water content, so it is necessary to make an appropriate setting according to the water content of the concrete floor slab 20 to be explored.

Since electromagnetic waves are radiated from various angles to the internal defect 21 in the present invention, _{not only the cover thickness D 2 of} the internal defect 21 but also the approximate shape of the internal defect 21 can be detected. The detected internal defect 21 is stored as three-dimensional data by the arithmetic unit 11.

Further, the vehicle 14 is loaded with the GPS receiving device 12 together with the electromagnetic wave radar device 10, and acquires the position data on the highway where the internal defect 21 is detected to identify the position of the internal defect 21. As a result, the position on the highway and the three-dimensional data of the internal defect 21 can be linked. The arithmetic unit 12 that performs the arithmetic processing described above may be mounted on the vehicle 14 or may be a server installed at a vehicle base on the ground or the like.

When using a server on the ground, the data may be stored in the storage means 19 mounted on the vehicle 14 and read into the server later, or the data may be transmitted to the server while traveling by wireless communication. Good.

In the present invention, a three-dimensional model is created from the three-dimensional data of the internal defect 21 thus obtained by using three-dimensional computer graphic software, and the CIM display device 13 superimposes the three-dimensional image on the photographic image of the highway and displays the CIM. CIM is an abbreviation for "Construction Information Modeling", and is a system that consistently shares information at each stage of design, construction, and management in the construction process by using a three-dimensional model.

FIG. 3 is a photographic image of a highway. The photographic image of this highway may be taken at the same time by a camera mounted on the vehicle 14, or may be taken separately. It may also be point cloud 3D data such as a mobile mapping system.

FIG. 4 is an image in which a three-dimensional model of the internal defect 21 is superimposed on a photographic image of an expressway having the same position data and displayed by CIM. Such a display in which the position can be visually specified and the inside of the road can be seen through is made possible by associating the position on the expressway with the position of the internal defect 21. As a result, it is possible to intuitively grasp at which position of the expressway the concrete slab 20 has the internal defect 21. Further, by running the vehicle 14 on a regular basis, it is possible to easily grasp the change in the shape of the internal defect 21 and the progress status, so that the maintenance of the expressway can be performed at an appropriate timing.

According to the present invention, the shape of the reinforcing bar or the like embedded in the concrete floor slab 20 can be displayed as shown in FIG. 4, and the corrosion status thereof can also be displayed three-dimensionally by CIM. It is possible to properly perform maintenance management.

10 Electromagnetic wave radar device 11 Arithmetic logic unit 12 GPS receiver 13 CIM display device 14 Vehicle 15 Transmission antenna 16 Receiving antenna 17 Control calculation unit 18 Display unit 19 Storage means 20 Concrete floor slab 21 Internal defect

Claims (3)

While driving on a highway, the concrete slab is continuously searched by an electromagnetic wave radar, and the internal defects of the concrete slab are acquired and modeled as three-dimensional data, and the internal defects are detected using GPS. Highway concrete slab using a perspective view, which is characterized by acquiring position data on an expressway and superimposing a three-dimensional model of the internal defect on a photographic image of an expressway having the same position data and displaying it in CIM. Internal defect detection display method. A claim characterized in that the position is visually specified by combining with a photographic image obtained while traveling on an expressway so that the inside of a concrete floor slab can be seen through, and the photographic image of the expressway is made into a moving image. A method for detecting and displaying internal defects in a concrete floor slab of an expressway using the perspective view according to 1. An electromagnetic wave radar device that is mounted on a vehicle and continuously explores the concrete slab while traveling on the highway, and GPS reception that is mounted on the same vehicle and acquires position data on the highway where internal defects are detected. A three-dimensional model of the internal defect is created from the device, an arithmetic device that acquires the internal defect of the concrete floor slab as three-dimensional data by using the electromagnetic wave propagation time of the electromagnetic wave radar, and the internal defect. An internal defect detection display system for a concrete floor slab of a highway using a perspective view, which comprises a CIM display device for displaying a CIM by superimposing a three-dimensional model on a photographic image of a highway having the same position data.

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