阅读说明：本技术 一种混凝土保护层厚度与钢筋间距检测的方法及其装置 (Method and device for detecting thickness of concrete protective layer and distance between reinforcing steel bars ) 是由 吴斌 李明智 刘秀成 杨硕 王鹤萤 何存富 于 2020-12-19 设计创作，主要内容包括：本发明公开了一种混凝土保护层厚度与钢筋间距检测的方法及其装置,装置包括上位机、运动控制模块、扫描机构、信号激励采集模块、孤立波传感器、信号处理模块、结果显示模块、存储模块、打印模块；检测方法为上位机通过运动控制模块控制扫描机构运动,扫描机构带动孤立波传感器移动到钢筋混凝土结构的不同位置,同时上位机通过信号激励采集模块控制孤立波传感器激励与采集孤立波检测信号,通过信号处理模块、结果显示模块、存储模块以及打印模块完成钢筋混凝土结构中保护层厚度与钢筋间距的检测。本发明结构简单,不仅可以检测钢筋混凝土结构中是否存在钢筋,还可以定量表征钢筋的保护层厚度与间距,进而防止钢筋混凝土结构出现相应的质量问题。(The invention discloses a method and a device for detecting the thickness of a concrete protective layer and the distance between reinforcing steel bars, wherein the device comprises an upper computer, a motion control module, a scanning mechanism, a signal excitation acquisition module, a solitary wave sensor, a signal processing module, a result display module, a storage module and a printing module; the detection method comprises the steps that the upper computer controls the scanning mechanism to move through the motion control module, the scanning mechanism drives the solitary wave sensor to move to different positions of the reinforced concrete structure, meanwhile, the upper computer controls the solitary wave sensor to excite and collect solitary wave detection signals through the signal excitation and collection module, and detection of the thickness of the protective layer and the distance between reinforcing steel bars in the reinforced concrete structure is completed through the signal processing module, the result display module, the storage module and the printing module. The invention has simple structure, can detect whether the reinforced concrete structure has the steel bars, and can quantitatively represent the thickness and the space of the protective layer of the steel bars, thereby preventing the reinforced concrete structure from generating corresponding quality problems.)

1. The utility model provides a device that concrete protective layer thickness and steel bar spacing detected for whether there is the reinforcing bar and to the quantitative characterization of steel bar protective layer thickness and interval in detecting reinforced concrete structure, its characterized in that: the device comprises an upper computer, a motion control module, a scanning mechanism, a signal excitation acquisition module, a solitary wave sensor, a signal processing module, a result display module, a storage module and a printing module; the solitary wave sensor is contacted with a detection sample of the reinforced concrete structure; the signal excitation acquisition module is used for exciting the solitary wave sensor to generate a solitary wave detection signal and acquiring the solitary wave detection signal received by the solitary wave sensor; the scanning mechanism drives the soliton wave sensor to move on the surface of the detection sample; the motion control module controls the scanning step length and the scanning interval of the scanning mechanism and uploads the motion information of the scanning mechanism to the upper computer; the signal processing module is used for drawing a C scanning image of a reinforced concrete structure detection result in combination with the scanning mechanism motion information uploaded by the motion control module when the sound of the solitary wave detection signal is calculated; the result display module can display a C scanning image of the detection result and mark the position and the burial depth of the steel bar; the storage module stores the solitary wave detection signal acquired by the signal excitation acquisition module and the detection result processed by the signal processing module; the printing module generates and prints a detection report of the distribution of the steel bars in the reinforced concrete result; the upper computer is used for controlling the modules.

2. The nondestructive testing method for the thickness of the concrete protective layer and the distance between the steel bars by using the device of claim 1 is characterized in that: the sound time parameter of the solitary wave detection signal changes along with the change of the surface rigidity of the reinforced concrete structure; when the steel bars exist in the structure below the detection area, the surface rigidity of the structure is increased, and the surface rigidity of the structure is increased when the steel bars are closer to the surface of the structure; the larger the structure surface rigidity is, the smaller the acoustic time parameter of the solitary wave detection signal is; and (3) quantitatively representing whether the reinforcing steel bars exist in the detection area and the thickness and the distance of the protective layer of the reinforcing steel bars by extracting the sound time parameters.

3. The nondestructive testing method for distribution of reinforcing steel bars in a reinforced concrete structure of claim 2, wherein: the signal excitation acquisition module is used for exciting the solitary wave sensor to generate a solitary wave detection signal and acquiring the solitary wave detection signal received by the solitary wave sensor; controlling the scanning step length and the scanning interval of the scanning mechanism by the motion control module, and uploading the motion information of the scanning mechanism to an upper computer; when the signal processing module is used for calculating the sound of the solitary wave detection signal, drawing a C scanning image of the detection result of the reinforced concrete structure by combining the scanning mechanism motion information uploaded by the motion control module; a step of displaying the C scanning image of the detection result by a result display module and marking the thickness and the distance of the protective layer of the steel bar; storing the solitary wave detection signal acquired by the signal excitation acquisition module and the detection result processed by the signal processing module by the storage module; and generating and printing a reinforced concrete structure detection report by a printing module.

Technical Field

The invention belongs to the technical field of nondestructive testing, and relates to a novel method and a device for testing the thickness of a concrete protective layer and the distance between reinforcing steel bars. The method comprises the steps of detecting the surface rigidity of the reinforced concrete structure by using an isolated wave technology, extracting sound time parameters of isolated wave signals, determining whether reinforcing steel bars exist in a detection area, and quantitatively representing the thickness and the distance of protective layers of the reinforcing steel bars.

Background

For a long time, the reinforced concrete structure is used as a main stressed structure in modern buildings and is widely applied to national major projects such as civil engineering, water conservancy and national defense. In a reinforced concrete structure, concrete has stronger compressive strength but weaker tensile strength; the steel bars have strong tensile strength but weak compressive capacity. Only when the two are matched and used cooperatively, the requirements of tensile strength and compressive strength of the structure can be met. In the process of construction, in order to pursue faster project progress and higher economic benefit, the problems that steel bars in a reinforced concrete structure are lost or the thickness and the distance of protective layers do not accord with construction requirements and the like are often caused. These problems can seriously affect the tensile and compressive strength of the reinforced concrete structure, and further pose a serious threat to social and personal safety. Therefore, the method has very important significance for detecting the existence of the steel bars in the reinforced concrete structure and the thickness and the distance of the protective layer.

Currently, the detection of steel bars in reinforced concrete structures mainly adopts an ultrasonic guided wave method, an electromagnetic induction method, a radar method, a direct method and the like. The ultrasonic guided wave method can detect the thickness and the distance of a protective layer of the steel bar and can also detect whether the steel bar generates a corrosion phenomenon, but the ultrasonic guided wave method has weak excitation signal energy and large signal attenuation in a concrete structure, so the detection depth is limited. The electromagnetic induction method and the radar method are not suitable for concrete containing other ferromagnetic substances (except steel bars) and cannot meet the requirements under different measurement scenes. The direct method belongs to a destructive detection method and cannot be applied to in-service detection.

The invention discloses a novel method and a device for detecting the thickness of a concrete protective layer and the distance between reinforcing steel bars, which are used for detecting the reinforcing steel bars by adopting a nonlinear solitary wave technology, overcome the defects of weak excitation signal energy, large attenuation in a concrete structure and the like, can meet the detection requirements under different scenes, and belong to a novel method for nondestructive detection of the thickness and the distance between the protective layer and the reinforcing steel bars in the reinforced concrete structure.

Disclosure of Invention

The invention relates to a novel method and a device for detecting the thickness of a concrete protective layer and the distance between reinforcing steel bars, and aims to provide a novel method for efficiently, conveniently and accurately detecting the presence of the reinforcing steel bars in a reinforced concrete structure and the thickness and the distance between the reinforcing steel bars in the reinforced concrete structure in a nondestructive mode. In order to achieve the above purpose, the technical scheme provided by the invention is as follows:

a detection device for detecting the thickness of a concrete protective layer and the distance between reinforcing steel bars is used for detecting whether the reinforcing steel bars exist in a reinforced concrete structure and the thickness and the distance between the reinforcing steel bars and the protective layer, and the device comprises: the device comprises an upper computer, a motion control module, a scanning mechanism, a signal excitation acquisition module, a soliton wave sensor, a signal processing module, a result display module, a storage module and a printing module; the isolated wave sensor is in contact with a detection sample of the reinforced concrete structure; the signal excitation acquisition module is used for exciting the solitary wave sensor to generate a solitary wave detection signal and acquiring the solitary wave detection signal received by the solitary wave sensor; the scanning mechanism drives the soliton wave sensor to move on the surface of the detection sample; the motion control module controls the scanning step length and the scanning interval of the scanning mechanism and uploads the motion information of the scanning mechanism to the upper computer; the signal processing module is used for drawing a C scanning image of a reinforced concrete structure detection result in combination with the scanning mechanism motion information uploaded by the motion control module when the sound of the solitary wave detection signal is calculated; the result display module can display a C scanning image of the detection result and mark the position and the burial depth of the steel bar; the storage module stores the solitary wave detection signal acquired by the signal excitation acquisition module and the detection result processed by the signal processing module; the printing module can generate and print a detection report of the distribution of the steel bars in the reinforced concrete result; the upper computer is used for controlling the modules.

A nondestructive testing method for the thickness of a concrete protective layer and the distance between reinforcing steel bars has the principle that the sound time parameter of an isolated wave detection signal changes along with the change of the surface rigidity of a reinforced concrete structure; when the steel bars exist in the structure below the detection area, the surface rigidity of the structure is increased, and the surface rigidity of the structure is increased when the steel bars are closer to the surface of the structure; the larger the structure surface rigidity is, the smaller the acoustic time parameter of the solitary wave detection signal is; and (4) representing whether the steel bars exist in the detection area and the thickness and the distance of the protective layer of the steel bars by extracting the sound time parameters.

The concrete implementation process of the nondestructive testing method for the thickness of the concrete protective layer and the distance between the steel bars comprises two parts of measurement and calibration.

The implementation mode of the measuring process comprises the following steps: the signal excitation acquisition module is used for exciting the solitary wave sensor to generate a solitary wave detection signal and acquiring the solitary wave detection signal received by the solitary wave sensor; controlling the scanning step length and the scanning interval of the scanning mechanism by the motion control module, and uploading the motion information of the scanning mechanism to an upper computer; when the signal processing module is used for calculating the sound of the solitary wave detection signal, drawing a C scanning image of the detection result of the reinforced concrete structure by combining the scanning mechanism motion information uploaded by the motion control module; a step of displaying the C scanning image of the detection result by a result display module and marking the thickness and the distance of the protective layer of the steel bar; storing the solitary wave detection signal acquired by the signal excitation acquisition module and the detection result processed by the signal processing module by the storage module; a step of generating and printing a reinforced concrete structure detection report by the printing module.

The implementation mode of the calibration process comprises the following steps: manufacturing reinforced concrete test pieces with different thicknesses of the reinforced protective layer; detecting concrete samples of the protective layer thicknesses of different steel bars by using the detection device; and performing function fitting on the nonlinear isolated wave sound time characteristics in the detection signal and the thickness of the protective layer to obtain a calibration curve.

By adopting the technical scheme, the influence of the thickness of the protective layer of the steel bar in the reinforced concrete structure on the surface rigidity of the structure is ingeniously reflected by the sound time characteristics of the solitary wave signals generated by the nonlinear solitary wave sensor, so that the relation between the sound time characteristics and the thickness of the protective layer of the steel bar is established, and the nondestructive detection of the existence of the steel bar in the reinforced concrete structure and the thickness and the distance of the protective layer is realized.

Drawings

FIG. 1 System Block diagram

FIG. 2 detection schematic diagram

FIG. 3 exemplary detection signals

FIG. 4 calibration curve of protective layer thickness versus reinforcement at acoustic time

FIG. 5 is a schematic diagram of the detection results

In the figure: 1-signal processing module 2-result display module 3-storage module 4-printing module 5-upper computer 6-signal excitation acquisition module 7-solitary wave sensor 8-reinforced concrete structure 9-scanning mechanism 10-motion control module 11-impact particles 12-particle chain 13-observation particles 14-concrete 15-reinforced steel bar

Detailed Description

In order to make the object, technical solution and advantages of the present invention clearer, embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

As shown in fig. 1, the apparatus for detecting the thickness of the concrete cover and the distance between the reinforcing bars of the present invention comprises: the device comprises an upper computer 5, a motion control module 10, a scanning mechanism 9, a signal excitation acquisition module 6, an isolated wave sensor 7, a signal processing module 1, a result display module 2, a storage module 3 and a printing module 4, wherein the isolated wave sensor 7 is used as a core, and the multifunctional instrument integrates data acquisition, storage, analysis, drawing and printing into a whole.

The invention provides a method for detecting the thickness of a concrete protective layer and the distance between reinforcing steel bars, which comprises the following steps:

1. as shown in fig. 2, the solitary wave sensor 7 is placed on the surface of the reinforced concrete structure 8, so that the terminal particles of the particle chain 12 in the solitary wave sensor 7 are closely attached to the surface of the concrete 14 in the reinforced concrete structure 8, so as to detect the existence of the steel bars 15 in the reinforced concrete structure 8 and the thickness and the distance between the protective layers.

2. The upper computer 5 is used for controlling the signal excitation acquisition module 6 to send out signals, impact particles 11 in the soliton wave sensor 7 are controlled to impact particles at the top end of a particle chain 12, and nonlinear soliton waves are generated in the particle chain 12 in an excitation mode.

3. The nonlinear solitary wave generated by excitation in the solitary wave sensor 7 propagates along the particle chain 12, is reflected after being propagated to the surface of the reinforced concrete structure 8, and then continues to propagate reversely along the particle chain 12. The recording is performed with the observed particle 13 in the soliton wave sensor 7. Fig. 3 shows typical detection signals, including incident soliton signals and reflected soliton signals.

4. The upper computer 5 is used for controlling the signal processing module 1 to extract the time difference between the reflected solitary wave and the incident solitary wave in the solitary wave detection signal, namely the sound time parameter. Fig. 4 shows a calibration curve of the thickness of the protective layer of the steel reinforcement at sound, by comparison with which it is determined whether the steel reinforcement and its protective layer thickness are present at the detection point.

5. The upper computer 5 is used for controlling the motion control module 10 to send signals to the scanning mechanism 9, the scanning mechanism 9 controls the solitary wave sensor 7 to move along the surface of the reinforced concrete structure 8 according to the step length set by the motion control module 10, and the steps 1-2-3-4 are repeated, so that sound time parameters of different positions can be obtained, and the existence of the steel bars 15 in the reinforced concrete structure 8 and the thickness and the distance of the protective layer of the steel bars 15 are represented.

6. And controlling the signal processing module 1 by using the upper computer 5 to draw a C-scan by taking the actual detection position and the sound time as coordinates. And displaying the detection result by using the result display module 2. Fig. 5 shows a schematic diagram of the detection result, in which the thickness and the distance of the protective layer of the steel bar 15 in the reinforced concrete structure 8 are shown by using the density of the vertical stripes (the detection result of the sparse vertical stripes is 10mm, the detection result of the dense vertical stripes is 50mm, the total filling of the vertical stripes is 100mm, and the rest positions are the positions where no steel bar exists).

7. The upper computer 5 is used for controlling the storage module 2 to store detection data and results, and controlling the printing module 4 to print a detection result chart and detection results of the existence of the steel bars 15 in the reinforced concrete structure 8 and the thickness and the distance of the protective layer.

8. Repeating the steps 1-7 to finish the nondestructive detection of the existence of the steel bars 15 in the reinforced concrete structure 8 and the thickness and the distance of the protective layer.