JP5968759B2 - Method for selecting repair method for concrete surface - Google Patents

Description

The present invention, the surface of the concrete structure optically analyzed, it relates to the repair method Selection of the concrete surface which can select the most appropriate repair method based on the analysis result.

  In order to evaluate the current state of concrete structures, it is necessary to evaluate the deterioration of concrete surfaces and reinforcing bars and quantify them to evaluate the performance of concrete structures.

  However, at present, no method has been established to quantitatively evaluate the various performances of concrete structures. In the deterioration evaluation by the Japan Concrete Institute, the actual shape of the concrete surface of the concrete structure is shown in Table 1. In this way, the performance of concrete structures is evaluated semi-quantitatively.

  In Table 1, the repair method is selected according to each state graded semi-quantitatively.

  As a method for diagnosing a concrete structure, there are individual differences in the observation of the appearance of the concrete surface by visual observation as described above, and nondestructive inspection and inspection by core removal are performed. It is not suitable for new structures because it requires repair after the position of the reinforcing bar is confirmed and the specimen is collected.

  In contrast, spectroscopic analysis as a nondestructive inspection can measure the distribution of chloride ion concentration and the like on the concrete surface in a short time.

  As proposed in Patent Documents 1 to 3, the present inventors irradiate the concrete surface with infrared rays, spectroscopically analyze the reflected light reflected from the concrete surface in a predetermined wavelength range, and perform chemometrics (metric chemistry). A system was established to detect calcium hydroxide and chloride ion concentrations with high accuracy using the multiple regression analysis method used.

Japanese Patent No. 503281 JP 2010-271062 A JP 2011-242376 A

  By the way, even if the distribution of chloride ion concentration and calcium carbonate concentration can be diagnosed by spectroscopic analysis of the surface of the concrete structure, we can quantitatively grasp the relationship between these concentrations and the deterioration state, and adjust to the deterioration state in Japan. A system that can select the repair method recommended by the Japan Concrete Institute has not yet been developed.

  The concrete structure has a large area such as a bridge or a tunnel, and even if the distribution of the concentration of chloride ions or the like can be measured on the concrete surface in Patent Documents 1 to 3 described above, the concentration distribution data is, for example, 50 × 100 mm. The data is divided into meshes, and the concentration distribution data can be used to identify the location where the chloride ion concentration on the concrete surface is high or to estimate the degree of deterioration. Not related.

When the chloride ion concentration on the lower surface of the concrete floor slab of the bridge was actually measured with the system described above, the chloride ion concentration distribution on the concrete surface changed greatly depending on the installation environment of the bridge, and it was installed along the seaside. On a concrete surface, the sea side is exposed to wind containing salt, so the chloride ion concentration is higher than the mountain side, and the wind hitting the concrete surface is uneven and uneven at the pier position and topography. The chloride ion concentration on the concrete surface was found to be distributed in a wide range of 0 to 10 kg / m ³ .

  Therefore, even if the concentration distribution of chloride ion concentration is accurately grasped by the system described above, the concrete surface is actually repaired, that is, the repair position is specified and the repair method is selected and repaired. Is a new issue.

An object of the present invention is to solve the above problems, to provide a repairing method Selection of the concrete surface which can be selected repair method with identifying the appropriate repair position and the like distribution of the chloride ion concentration detected spectrophotometrically There is.

In order to achieve the above-mentioned object, the invention of claim 1 makes the concrete deterioration state correspond to the chloride ion concentration with respect to each grade of the concrete surface deterioration state defined in appearance, and for each grade. Set the concentration range corresponding to each grade by setting the range of chloride ion concentration value, determine the recommended repair method for each concentration category, and then the concrete surface to be repaired, The mesh is divided into meshes, and infrared spectroscopic analysis is performed to measure the chloride ion concentration of each mesh, and a contour diagram based on the concentration category is created from the chloride ion concentration of each mesh, and is expressed in the contour diagram. For each aggregate of concentration categories, categorize the repair method for the concrete surface that is to be repaired by dividing it with a division line so that the aggregate of the concentration category is included in order from the high concentration category. That together, the combined cracked regions of the concrete surface expressed in the contour plot, repairing method selection of the concrete surface, characterized in that the partition at section line a collection of cracked area as the same repair method and the high density bin Is the method.

According to a second aspect of the invention, when divided by division lines, while proximity aggregate of density bins in contour plots, repairing method of concrete surface according to claim 1, wherein partitioning collectively proximity assemblage This is a selection method.

The invention of claim 3, repair density bins that exceeds the chloride ion concentration 4.8 kg / m ³ method 4, the chloride ion concentration 2.4~4.8kg / m ³ of density bins repair method 3, chloride ion concentration 1.2~2.4kg / m ³ of density bins repair method 2, repairing method 1 the concentration section of chloride ion concentration 0~1.2kg / m ^3, and unnecessary repair when not detecting a chloride ion The method for selecting a repair method for a concrete surface according to claim 1 or 2 , wherein the concrete section is repaired by repair method 4, the anticorrosion desalination is performed by repair method 3, and the reinforcing bar is passivated by repair method 2. It is.

  According to the present invention, the concrete deterioration state defined in appearance is defined by chloride ion concentration, the concrete surface is divided by mesh, chloride ion concentration is obtained for each mesh, and based on the chloride ion concentration for each mesh. By creating a contour map corresponding to the concrete deterioration state, it is possible to select an appropriate repair method according to the deterioration state.

In this invention, it is a figure which shows the whole spectrum analyzer of a concrete surface. It is a figure which shows the detail of the probe head of FIG. (A) shows the outline of scanning of the probe head when performing spectroscopic analysis of the concrete surface S, and (b) to (e) are diagrams showing absorbance spectrum data at each scanning position of the probe head. It is a figure which shows the general | schematic flow of the repair method selection method of the concrete surface of this invention. In this invention, it is a contour figure when a chloride surface concentration is measured for every mesh on a concrete surface. It is the contour figure which displayed the contour figure of FIG. 5 by the density | concentration division according to the grade of a concrete deterioration state. It is a figure which shows the point which divides the repair area _| region _MGH corresponding to the repair construction method 4 from the contour figure of FIG. It is a figure which shows the point which divides the repair area | region _MEF corresponding to the repair construction method 3 from the contour figure of FIG. Repair area M _D corresponding the contour diagram repairing method 2,1 of Figure 6, showing the manner for dividing the M _BC. It is a figure which shows the repair area | region divided in FIGS.

  A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings.

  First, the spectroscopic analyzer 10 for a concrete surface will be described with reference to FIGS.

  The spectroscopic analyzer 10 is connected to a probe head 11 that travels along a concrete surface and spectrally analyzes the concrete surface, and is connected to the probe head 11 via a cable 12 to control the probe head 11 and from the probe head 11. A control box 13 that captures information, and a computer 15 that is connected to the control box 13 via the USВ cable 14 and controls the probe head 11 via the control box 13 and captures spectral analysis results and measurement position information from the probe head 11. It consists of. Although not shown, the power cables 16 and 17 of the control box 13 and the computer 15 are connected to a portable power source.

  As shown in FIG. 2, the probe head 11 includes a light source 19 that irradiates the concrete surface S with near-infrared light having a wavelength range of 0.9 to 2.5 nm from visible light, such as a halogen lamp, in the head body 18. At the same time, the light receiving unit 21 that receives the reflected light reflected from the concrete surface S and enters the optical fiber 20 is accommodated. Further, the head body 18 is provided with wheels 22 that run on the concrete surface S, and an operation pole 23 is rotatably provided at the top of the head body 18, and the operator holds the operation pole 23 and the probe head 11. Can be scanned along the concrete surface S.

  Further, although not shown, the wheel 22 is provided with a rotary encoder, and the traveling distance of the probe head 11 with respect to the concrete surface S is detected by the rotation of the wheel 22, and the signal line 24 of the rotary encoder and the power cable 25 of the light source 19 are detected. And the optical fiber 20 are provided in the operation pole 23 or along the operation pole 23, and the cable 12 extending from the operation pole 23 is connected to the control box 13.

  The spectroscopic analysis of the concrete surface S by the spectroscopic analysis apparatus 10 is performed by spectroscopically analyzing the probe head with the length of the concrete surface S when the concrete surface S on the lower surface of the concrete floor slab of the bridge is spectroscopically analyzed as shown in FIG. As shown in FIG. 3 (b) to FIG. 3 (e), this is traveled in the direction and spectrally analyzed at intervals of 50 mm. The position (50 mm, 100 mm, 150 mm, 200 mm,...) Is stored in the computer 15 as spectroscopic analysis data. Next, when the measurement of one measurement line is completed, the scanning position is shifted by 100 mm, and the concrete surface at the running position (S02) Spectral analysis of S is used as data, and then the entire surface of the concrete surface S is spectrally analyzed by sequentially changing the scanning position every 100 mm pitch.

  By running the probe head and spectroscopically analyzing the concrete surface in this way, spectroscopic analysis data of 50 × 100 mm mesh can be obtained.

  Data obtained by spectroscopic analysis of the concrete surface S is spectral data of wavelength and absorbance, and each mesh is analyzed by chemometrics multiple regression analysis based on a calibration curve previously prepared with chloride, neutralization, and water-cement ratio. The chloride ion concentration is obtained.

This chloride ion concentration is the chloride ion concentration on the concrete surface, and the deterioration degree due to chloride represents a more accurate deterioration degree when the chloride ion concentration at the reinforcing bar position is evaluated in consideration of fogging. Therefore, using the error function (erf (x)), the following equation (1) is obtained with a complementary error.
C _d = γ _cl · C ₀ {1-erf (0.1 _{c d} / 2 (D _d / t) ^1/2 )} (1)
C _d : Chloride ion concentration at the reinforcing bar position (kg / m ³ )
C ₀ : Chloride ion concentration on the concrete surface (kg / m ³ )
c _d : design value (mm) of the cover, c _d = c−Δc ₀ ,
(C: fog (mm), Δc ₀ : construction error (mm))
t: Service life against intrusion of chloride ions (shared years) (years)
γ _cl : Safety factor considering variation in chloride ion concentration C _d at the position of reinforcing _bar D _d : Design diffusion coefficient for chloride ion (cm ² / year)

  In the spectroscopic analysis using the probe head described above, an example is mainly described in which the chloride ion concentration is measured, but the calcium carbonate concentration on the concrete surface is obtained from the obtained spectrum data, and the calcium carbonate concentration at the reinforcing bar position. Also ask for.

  In addition to chloride ion concentration and calcium carbonate concentration, the concrete surface is also cracked. This crack is caused by mounting a CCD camera on the probe head, processing the image of the CCD camera, displaying the crack on the mesh image of the chloride ion concentration, or extracting natural light from the spectrum data and measuring its density. Either a crack may be detected from the value, or a crack may be extracted from an image obtained by imaging the entire concrete surface, and the crack may be displayed on a mesh image of chloride ion concentration.

  Next, a schematic flow of a concrete surface repair method selection method using the spectroscopic analysis apparatus 10 shown in FIG. 1 will be described with reference to FIG.

  In step S10, the spectroscopic measurement of the concrete surface is performed in mesh units, and then the absorbance spectrum data obtained by the spectroscopic analysis is subjected to chemometric multiple regression analysis (step S11), and the chemometric multiple regression for each mesh is performed. Information on the distance of the mesh is input to the chloride ion concentration obtained by the analysis (step S12), and the degree of deterioration of the mesh is expressed from the position of the mesh and the chloride ion concentration (step 13). Based on the chloride ion concentration value on the surface of the mesh, the input of the cover, the input of the diffusion coefficient, the threshold values such as the service life and safety coefficient are input to the arithmetic expression of the above formula (1) (step S14). The chloride ion concentration on the surface is obtained, and the degree of deterioration of the reinforcing bar is described (step S15). After that, in step S16, the contour map of the concrete surface is written, and in step S17, the repair area and the repair method are written from the contour map.

  After that, the actual concrete surface is repaired from the indicated repair area and repair method.

  FIG. 5 shows a measurement example of the contour diagram 30 expressed in step S16 of FIG. This contour diagram 30 shows a spectroscopic analysis of a concrete surface (16186 × 11900 mm) of 16186 (mm) in the width direction of a concrete slab of a floor slab (for example, 330 mm in width) and 11900 (mm) in the length direction of the concrete girder with a probe head. Chloride ion concentration is shown in shade values for each mesh. The number of meshes is 50 mm in the width direction (probe head running direction), and 100 mm in the length direction (probe head measurement pitch). The surface is shown divided into 324 × 119 mesh. The upper part of the contour map 30 is the sea side, and the lower part is the mountain side.

  In FIG. 5, the contour diagram 30 in which the chloride ion concentration at the reinforcing bar position is obtained from the chloride ion concentration on the concrete surface shows cracks in the reinforcing bar at the same time.

In this contour diagram 30, in each mesh, chloride ion concentration, toward the low concentration of the high concentration, 4.8 kg / m ³ or more concentrations segment G, 3.6~4.8kg / m ³ of density bins F, 2.4-3.6 kg / m ³ concentration category E, 1.2-2.4 kg / m ³ concentration category D, 0.6-1.2 kg / m ³ concentration category C, 0-0.6 kg / G ³ concentration section B, concentration section A without chloride ions is divided by contours in a range of 7 stages, and meshes entering each of the concentration sections G to A are assembled to collect aggregates G ₁ , G ₂ , F ₁ , E ₁ , D _{1 to} D ₆ , C ₁ , C ₂ , B ₁ , B ₂ , and A ₁ are displayed, and crack aggregates H ₁ and H _{2 in} the crack region H are also displayed.

In the contour diagram 30, the aggregates G ₁ and G ₂ of the high-concentration section G are located at the bottom surface of the girder one inside the bottom surface of the girder on the sea side, and at a position close to the pier.

  The present inventors examined the correlation of chloride ion concentration with respect to appearance deterioration evaluation by the Japan Concrete Institute shown in Table 1, and the states classified by the deterioration evaluation in Table 1 are shown in Table 2. It was found that each concentration range corresponds to the state by dividing by chloride ion concentration, calcium carbonate concentration and cracks.

Here, state I-1 (latent period) has a chloride ion concentration of 0 to 1.2 kg / m ³ , calcium carbonate concentration of 0 to 20 mass%, and state I-2 (progression period) has a chloride ion concentration of 1.2. ~ 2.4 kg / m ³ , calcium carbonate concentration 20 to 40 mass%, states II-1 and II-2 (early acceleration period and late acceleration period), chloride ion concentration 2.4 to 4.8 kg / m ³ , The calcium carbonate concentration is 40-60 mass%, the state III (deterioration stage) is chloride ion concentration of 4.8 kg / m ³ or more, calcium carbonate concentration is 60 mass% or more, and cracks are evaluated by the number and length per 1 m ^2. According to these states I to III, the repair methods 1 to 4 recommended by the Japan Concrete Institute were defined in the numerical ranges of chloride ion concentration and calcium carbonate concentration.

  The repair method 1 in the state I-1 in Table 2 is a method of coating the surface with mortar, and the repair method 2 in the state I-2 is made to passivate by reacting with a rusted rebar with an aqueous lithium nitrite solution. In the repair method 3 in the state II-1 and II-2, a reinforcing bar is used as a cathode, an anode material lower than iron is arranged on the surface of the repaired portion, a direct current is passed between them, It is a method of regenerating concrete to a healthy pH by infiltrating the alkalate solution, and repair method 4 in state III is a method of repairing the concrete after directly repairing the reinforcing bar by rolling up the concrete at the repair location to the reinforcing bar. .

  In the repair methods 1 to 4, the repair method 4 has a concrete surface, so the degree of work is high. The repair method 3 is cathodic, and in order to pass a direct current, a part of the reinforcing bar is exposed. It is necessary, and after repair method 4, there is difficulty. Further, repair method 2 allows a lithium nitrite solution to penetrate, and repair method 1 can be repaired relatively easily because of surface coating with mortar.

FIG. 6 is a contour diagram based on the repair methods 1 to 4 based on Table 2 and from the concentration categories G to A of the chloride ion concentration diagram 30 of FIG. 5 to the concentration categories based on the repair methods 1 to 4. 31 is created. Concentration section F and concentration section E are integrated into concentration section EF with respect to contour chart 30 of seven-stage concentration sections G to A in FIG. The aggregates G ₁ , G ₂ , EF ₁ , D _{1 to} D ₆ , ВC ₁ , ВC _{2 are} divided into 5 levels of concentration categories G, EF, D, BC, and A. , A ₁ and a contour diagram 31 displaying the aggregates H ₁ and H ₂ of the cracked region H are shown.

  In addition, although the contour figure by the calcium carbonate by neutralization is not displayed in this embodiment, as shown in Table 2, the chloride ion concentration and the degree of neutralization are related, and the basic contour The illustration is omitted because it is the same as FIG.

In the contour diagram 31 of FIG. 6, the repair method 4 corresponds to the aggregates G ₁ and G ₂ of the concentration category G, and the aggregates H ₁ and H _{2 of the} crack region H, and the repair method 3 corresponds to the aggregate of the concentration category EF. body EF ₁ is applicable, repairing method 2, assembly D ₁ to D ₆ of density bins D, repairing method 1 aggregate a ₁ concentration segment a corresponds.

In this way, aggregates G ₁ , G ₂ , EF ₁ , D _{1 to} D ₆ , ВC ₁ , ВC ₂ , A ₁ , H in the concentration categories G, EF, D, BC, A corresponding to the repair method 4 to _{1 By} making the contour map 31 displaying ₁ and H ₂ , it is possible to select repair methods 1 to 4 and specify the repair location from the contour map 31.

Incidentally, the contours view 31 of Figure 6, assembly G _1, G ₂ corresponding to the repair method 4 are contiguous and, also cracked assembly H _1, H ₂ closely, cracking assembly H ₂ The tip and the assembly G ₂ are relatively close to each other, and the assemblies D ₃ , D ₄ , D ₅ corresponding to the repair method 2 are also relatively close to each other, and the assemblies G ₁ , G ₂ , H ₁ , H ₂ and the assemblies D ₃ , D ₄ , and D ₅ are individually repaired, the number of repair points increases, which is uneconomical.

Therefore, the repair region M _GH corresponding to the repair method 4 and the repair method 3 are indicated by the dividing line L according to the degree of assembly of the aggregates G ₁ , G ₂ , H ₁ , H ₂ , D ₃ , D ₄ , and D _5. The repair area M _EF corresponding to the repair method 2, the repair area M _D corresponding to the repair method 2, the repair area M _{ВC of} the repair method 2, and the repair area M _A corresponding to the repair method 1 are divided in order as shown in FIGS. .

  This division may be performed by dividing the contour diagram 31 by collecting a set of density segments by image processing, or by dividing the contour diagram 31 by a division line L from the contour diagram 31.

FIG. 7 shows a procedure for _dividing the repair region _MGH corresponding to the repair method 4 from the contour diagram 31.

As described above, in the contour diagram 31 of FIG. 6, the aggregates G ₁ and G ₂ corresponding to the repair method 4 are close to each other, and the crack aggregates H ₁ and H ₂ are also close to each other. The tip of ₂ and the assembly G ₂ are relatively close to each other. Therefore, as shown in FIG. 7, the repair method 4 is repaired by dividing it by a dividing line L ₄ composed of straight lines (or curves) so as to collectively include these aggregates G ₁ , G ₂ , H ₁ , H _{2. Segment the} region M _GH . At this time, the dividing line L ₄ is set with a margin (about 100 to 300 mm) away from the aggregate G ₂ and the aggregate H ₂ adjacent to the dividing line L ₁ . The margin dimension can be freely set in consideration of the accuracy of the apparatus.

FIG. 8 shows a procedure for dividing the repair region _MEF corresponding to the repair method 3 from the contour diagram 31.

In FIG. 7, the repair region M _GH includes a part of the assembly EF ₁ corresponding to the repair method 3 and is divided by the dividing line L _{4. In} FIG. 8, the repair region M _GH includes all the remaining assemblies EF _1. The repair area M _EF corresponding to the repair method 3 is sectioned by dividing into the section line L ₃ .

Figure 9 is a repair region M _D corresponding to the repairing method 2, and the repair region M _BC corresponding to the repair method 1, but the procedure for dividing the repair area M _A repairing unnecessarily corresponding been shown.

Repair area M _D corresponding to the repair method 2, partitioning is partitioned by dividing line L ₂ to include collectively assembly D _1, D ₃ ~D ₅ which adjacent. At this time, the aggregate D ₆ is distant from the aggregates D _{1 to} D ₅ , and the area of the aggregate D ₆ is small, so it is ignored without being included in the repair region M _EF . Then the repair area M _BC corresponding to the repair method 1, the repair region M and the remaining aggregate VC ₁ contained part _EF, aggregate A ₁ separation line including a collection VC ₂ within L ₁ in compartments and then divided, and the remaining aggregate a ₁ repair unnecessary repair area M _a from the compartment of dividing line L _1.

  In this way, by dividing each repair region M, it is possible to create a repair region M corresponding to the repair method 4 to 1 on the concrete surface as shown in FIG.

  After the repair area M is divided in this way, the actual concrete surface S may be divided by the dividing line L and repaired by repair methods 1 to 4 corresponding to the repair area M.

10 spectrometer 11 probe head 13 control box 15 computer 31 contour diagram G~A density bin G ₁ to A ₁ aggregate M _GH ~M _BC repair area

Claims (3)

For each grade of concrete surface deterioration specified in appearance, the concrete deterioration state is made to correspond to chloride ion concentration, and the range of chloride ion concentration value is set for each grade for each grade. Set the corresponding concentration categories, determine the recommended repair method for each concentration category, then divide the concrete surface to be repaired into meshes and perform infrared spectroscopy analysis for each mesh. The chloride ion concentration of each mesh is measured, and a contour map based on the concentration category is created from the chloride ion concentration for each mesh, and the concentration of each concentration category indicated in the contour diagram is successively increased. with partitioning repair method of the concrete surface to be repaired and partitioned by partition lines so as to include the collection of the density bins from partition, concrete surface in the contour plot The combined cracked region denoted, repairing method Selection of the concrete surface, characterized in that the partition at section line a collection of cracked area as the same repair method and the high density section. When divided by division lines, while proximity aggregate of density bins in contour plots, repairing method Selection of concrete surface according to claim 1, wherein partitioning collectively proximate aggregate. Repair density bins that exceeds the chloride ion concentration 4.8 kg / m ³ method 4, the chloride ion concentration 2.4~4.8kg / m ³ of density bins repair method 3, the chloride ion concentration 1.2-2 .4 kg / m ³ concentration category repair method 2, chloride ion concentration 0-1.2 kg / m ³ concentration category repair method 1, no repair required when chloride ion is not detected, repair method 4 The method for selecting a repair method for a concrete surface according to claim 1 or 2 , wherein cross-section repair is performed, the anticorrosion desalination is performed by the repair method 3, and the reinforcing bar is passivated by the repair method 2.