JPH05264489A - Prospecting method for cavity of slope surface of covered body - Google Patents

Abstract

PURPOSE:To capture the position and the depth of a cavity which is generated on the slope surface of a covered body such as a concrete mortar sprayed surface, etc. CONSTITUTION:In a slope surface where a covered body is formed on a naturally inclined surface, the surface temperature of the covered body is measured using infrared ray radiation thermometer and then the obtained temperature data and a visually judged data by observing the state of the slope surface of the covered body are combined. Both data are analyzed by a data processing device to obtain a discrimination function for detecting the state-changed part of the slope surface of the covered body and an estimation function of the depth of the cavity which exists between the naturally inclined surface and the covered body and then the position and the depth of the cavity which is generated between the naturally inclined surface and the covered body are prospected based on both functions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cavity exploration method for a covering slope for exploring cavities or the like formed on a covering slope of a building, such as concrete mortar.

[0002]

2. Description of the Related Art On a slope where natural mortar (hereinafter referred to as mortar) is sprayed on a natural slope such as a natural ground, cracks are generated on the surface of the mortar due to repeated expansion and contraction due to temperature changes day and night and permeation of rainwater. Occurrence or deformation such as weathering of the ground occurs. As this progresses, weathered earth and sand flow out toward the bottom of the slope, or mortar material is pushed out to create cavities between the mortar material and the slope, which causes the mortar to peel off and fall, and to promote slope slippage, etc. It is extremely dangerous. Conventionally, such a method of exploring a mortar member and a cavity formed on a natural slope has been one in which a person hits the surface of the mortar with a hammer or the like, and determines the presence or absence of the cavity by the level of the hitting sound. Also, due to the rising and peeling of exteriors such as mortar and tiles of building structures such as buildings,
Japanese Patent Publication No. 63-61603 discloses a method for detecting the cavities formed on the back side of these cavities from the spatial temperature distribution (temperature difference) measured by an infrared radiation thermometer. This method is roughly as follows. That is, when the temperature rises and the sunlight or artificial irradiation heat hits the exterior, a part thereof is reflected and the rest is absorbed by the exterior. Further, the absorbed energy is conducted to the base. Generally, the thermal conductivity decreases in the order of solid, liquid, and gas, so if there is peeling or there is a cavity in the exterior, the heat is stored in the exterior as much as the heat conductivity is low and compared to a healthy part without peeling. Relatively high temperature. The disclosed detection method measures the surface temperature of a building structure with an infrared radiation thermometer, and from the difference in its spatial distribution and temporal distribution, normal sound parts and abnormal parts with peeling or cavities are detected. The judgment is made. Such a method is effective in the case of detecting and analyzing an object such as an exterior of a building or a base and a structure in which the structure is formed substantially uniformly.

[0003]

However, the former exploration method described above, that is, the method of hitting the mortar with a hammer, depends on the empirical feeling of the judge, and therefore the judgment criteria can be shown quantitatively. Have difficulty. In addition, since such mortar surface is often formed as a steep slope,
The exploration work is accompanied by danger, and it is necessary to hit the entire area of the mortar surface to be explored, which is a disadvantage that the work efficiency is extremely poor. Also, the latter method of exploring exteriors such as buildings using infrared radiation thermometers is targeted at relatively homogeneous structures, unlike the natural ground. Therefore, even if such an exploration method is simply applied to mortar exploration on a natural slope, a large amount of measurement error will be included. When observing natural rocks, the slopes of such rocks are composed of materials with various characteristics such as hard rocks, soft rocks, weathered rocks, and soil. Therefore, when forming the mortar surface, the thickness of the mortar surface actually formed is uneven mainly due to construction problems. Furthermore, since the surface of the slope is uneven and has a complicated curved surface, the irradiation temperature becomes uneven when sunlight is used as the heat source. So for these reasons,
Just because the surface temperature is higher than that of the sound part or the temperature rising rate (falling rate at night) is large, it is not possible to judge that the cavity exists based on these alone. Furthermore, when investigating the deformation of the slope over a wide area, if the distance between the infrared radiation thermometer and the slope is not sufficient at the observation site due to topography etc., the target slope can be divided (scene) for observation. Not a few. Therefore, there is a time lag in the observation of each scene. Therefore,
If the observation scenes are different, even if they are observed at the same temperature, the information on the slope state obtained from them is also different. Therefore, when dividing and observing the slope of the ground, it is necessary to standardize the surface temperature between each observation scene so that it can be handled uniformly. As described above, regarding the mortar spraying slope that covers the natural slope of the natural ground, a healthy part and an abnormal part (cavity) can be identified only by the spatial distribution of the surface temperature (temperature difference) and the temporal change of the surface temperature. It is generally difficult to make a distinction, and it is necessary to determine the presence or absence of a cavity in consideration of the above-mentioned various factors other than the surface temperature. Therefore, the present invention solves the above-mentioned conventional inconveniences, and provides a cavity exploration method of a covering slope capable of quantitatively determining a cavity generated in a covering slope such as a mortar surface formed on a natural slope. The purpose is to do.

[0004]

In the method for locating a cavity on a slope of a cover according to the present invention, for example, as shown in FIG. 1, infrared radiation temperature detecting means 1 is used for a slope having a cover formed on a natural slope. The surface temperature of the coated body is measured by combining the obtained temperature data and the visually readable data obtained by observing the state of the coated body slope surface, and both of these data are analyzed by the data processing means 5 to determine the deformed portion of the coated body slope surface. A discriminant function to be detected and an estimation function of the depth of the cavity existing between the natural slope and the cover are created, and the position of the cavity and its depth are obtained based on these two functions.

[0005]

[Function] When exploring a cavity on a slope where natural slopes are covered with mortar, the surface temperature of the slope is measured, and in addition to such surface temperature data, visual interpretation data such as cracks on the mortar surface are imported. Furthermore, the visual interpretation data of the unevenness of the mortar surface and the surface temperature data between the divided observation scenes are standardized and incorporated. From these data, the discriminant function for detecting the deformed part of the mortar and the estimation function indicating the depth of the cavity existing between the natural slope and the mortar are calculated, and the presence or absence and the depth of the cavity in these functions are calculated. The presence or absence of a cavity and its depth can be obtained by adding the visual data of the observation points whose height is unknown. In this way, the exploration of the covering, which has been performed empirically in the past, can be performed objectively and quantitatively, so the cavity detection is highly reliable and the position and depth of the cavity can be calculated. It becomes possible with high efficiency, and is extremely useful for repair and maintenance of coatings.

[0006]

EXAMPLES Prior to the description of the examples, the quantification theory used in the present invention will be described. The quantification theory represents not only quantitative changes such as temperature, but also data concerning the quality of irregularities or the size of cracks that occur in coatings such as concrete in terms of quantities, in order to perform various analyzes and estimations. To do. The present invention utilizes the quantification theory classes II and I, the outline of which will be described below. Quantification Theory II
The class is intended to classify a qualitatively measured variable (external criterion) based on the above-mentioned qualitative information (explanatory variable), and in the case of the present invention, for example, it exists inside the coating. The external reference is the presence or absence of a cavity to be used. Each sample has an external criterion consisting of k classifications and a category of r items (factors-explanatory variables) (categorized item contents).
React to any of. Therefore, in the present invention, 1 is reacted when any category is reacted, and 0 otherwise.
The dummy variable is added. Therefore, let the dummy variable be δ
If it is (jk), it can be expressed as follows.

[0007]

[Equation 1]

At this time, it is assumed that the value (sample score) Yiα given to each sample is obtained in the dummy variable linear format as shown below. Here, a _jk is a real number and is called a category score.

[0009]

[Equation 2]

That is, the k groups are best discriminated by the sample score given to each sample, that is, the correlation ratio η ² (the ratio of the group variance to the total variance of the sample score) is maximized. In addition, the category score a is calculated by using each variable of sample points created by the procedure described later.
_{If jk} is calculated, the discriminant function can be obtained. Therefore, in the present invention, if the explanatory variable of the point where the presence or absence of a cavity is unknown is substituted into the obtained discriminant function, that is,
Since one sample point belongs to any one category in one item, the sample score (Yiα) can be calculated by adding the category score (a _jk ) corresponding to these, and the presence or absence of a cavity can be calculated by this positive / negative. It will be possible to determine. Therefore, when the discriminant function is obtained by assigning a value of 2 to the external reference with a void and a value of 1 to the absence of a void, the sample score of a new point is a positive value with zero as the threshold. If there is a cavity at that point, on the contrary, if it is a negative value, it can be determined that there is no cavity.

On the other hand, the quantification theory class I attempts to estimate a quantitatively measured variable (external criterion) by using qualitative information as an explanatory variable, and a sample score Y given to each sample. It is assumed that _i is obtained in the linear form of dummy variables as in the quantification theory class II.

[0012]

[Equation 3]

The above equation is basically the same structure as the multiple regression model. Therefore, in the present invention, the data obtained by the procedure described later is used to minimize the residual sum of squares of the sample score Y _i given to each sample and the observed value y _i of the cavity depth which is an external reference. Then, by _obtaining the category score b _jk by calculation and substituting the explanatory variable of the point where the cavity depth is unknown, the cavity depth can be estimated.

With reference to FIGS. 1 to 4, an embodiment of the method for detecting a cavity on the surface of a coated body of the present invention will be described below. This embodiment will be described with reference to the flowchart of FIG. The measurement is started by the infrared radiation thermometer 1, and the spatial distribution (temperature difference) of the surface temperature of the target concrete mortar slope and the temporal change are measured. At this time, when the slope to be surveyed cannot be supplemented with one observation scene (one section), the slope to be surveyed is divided and observed, and these temperature information are stored in the storage medium of the data recording device 2. (Step S1). On the other hand, by visually observing cracks and irregularities on the surface of concrete mortar,
~ Classify into 4 stages and record the position and degree (step S2). For example, these classifications are classified as explanatory variables as shown in the table below. In this table, each item (explanatory variable) indicating the qualitative information in the left column is given in several required stages such as a category (external criterion) in the right column.

[0015]

[Table 1]

Next, some required observation scenes (sample scenes) are selected, and a plurality of sample points in these observation scenes are selected (step S3). For the selected plurality of sample points, the surface temperature and its temporal change data are extracted from the temperature information recorded in step S1 (step S4). In this case, as the surface temperature of different observation scenes, the value of the corrected surface temperature is adopted by the equation (4) described later. As for the temporal change of the surface temperature, the temperature difference obtained from the temperature data obtained by observing the observation time with a constant observation time is used for each observation scene. Furthermore, for a plurality of sample points, hammering is used to determine the presence or absence of cavities, or a hole such as a few centimeters in diameter is made on the mortar surface with a drill, etc., and the presence or absence of cavities and the depth of cavities are manually determined. Measure (step S5). When the measurement of the surface temperature by the infrared radiation thermometer 1 and the visual observation are completed, step S2
~ Input the data obtained in S5 to the data processing device 5,
A discriminant function representing the presence or absence of a cavity by the above-mentioned equation (2),
An equation (3) is used to calculate and obtain an estimation function indicating the depth of the cavity (step S6). The accuracy of the obtained discrimination and estimation function is verified, that is, the presence / absence of the cavity and its depth at the sample point measured manually in step S5, and the presence / absence of the cavity and the depth of the computed both functions. If the result is compared with the data and the result is satisfied, the process proceeds to the next step S8, but if not satisfied, the step S8 is performed.
It returns to 3 and is repeated until a satisfactory result is obtained (step S7). Next, in step S1, surface temperature and surface temperature change data of the entire slope to be investigated are extracted from the temperature information of the mortar surface recorded in the recording medium of the data recording device 2, and these data are used in step S2.
The visually readable data obtained in step 1 are combined and converted into numerical data as explanatory variables. Further, as will be described later, a correction for standardizing the surface temperatures of a plurality of different observation scenes is added (step S8). These explanatory variables and the corrected surface temperature data are used together with the discriminant function of the presence / absence of the cavity obtained in step S6 and the manually observed value of the cavity depth observed in step S5, and the estimation function of the cavity depth obtained in step S6. Then, the position and depth of the cavity on the target slope are obtained (step S9). The above processing is performed on all the target slopes, and the measurement is completed.

When the coating 4 is divided into a plurality of observation scenes for measurement, the surfaces of different observation scenes are treated so that the surface temperature between the observation scenes can be treated in a unified manner in consideration of the time lag. Temperature needs to be standardized. Therefore, the following correction is added to the measured surface temperature.

[0018]

[Equation 4]

Here, t _ij is the measured temperature, M _i is the minimum temperature of the observation scene i, and M is the minimum temperature of the entire slope.

In this way, it becomes possible to carry out the cavity exploration on an objective and quantitative basis as compared with the cavity exploration method which has been conventionally conducted empirically.

FIG. 2 is a schematic diagram showing the structure of an apparatus for realizing the embodiment shown in FIG. Reference numeral 1 denotes an infrared radiation thermometer, which measures the surface temperature of a coating body 4 such as concrete mortar sprayed on the inclined surface of the ground 3, and a cavity a formed on the back side of the coating body 4 based on the obtained temperature data. Search for abnormal areas such as. 2 is a data recording device, 1 infrared thermometer
The temperature data detected by is stored and retained in a recording medium such as a floppy disk. Reference numeral 5 is a data processing device such as a personal computer, for example, which receives temperature data detected by the infrared radiation thermometer 1 and visual data of the covering 4, and performs various calculations and analysis. 6 is output from the data processing device 5. A printer / plotter for drawing or printing from data.

Next, the validity of the present invention will be described with reference to FIGS. 3 and 4. Figure 3 shows three observation scenes (A),
It shows the hit rate of cavity exploration by the discriminant function in (B) and (C). In FIG. 3, (A) shows the results of observation scene 1, (B) shows the results of observation scene 2, and (C) shows the results of observation scene 3. In this case, the horizontal axis represents the sample score of each sample point of each scene. For each sample point, if the sample score is positive, it is determined that there is a void, and if it is negative, it is determined that there is a void, and x is a void and O is a void. Expressing the accuracy rate of discrimination as a percentage of the number of misclassification samples to the total number of samples (precision rate),
Observation scenes 1 and 2 in (A) and (B) are about 97, respectively.
%, And the observation scene 3 in (C) is 100%,
In the observation scenes 1 and 2 of (A) and (B), some misjudgment was observed in the central portion, but almost satisfactory results were obtained.

FIG. 4 shows the measured values relating to the depth of the cavity (horizontal axis).
And the estimated value (vertical axis) are compared. In this example as well, there is no large difference between the actual measured value and the estimated value, indicating that a substantially good estimated value can be obtained.

In this way, it becomes possible to objectively and quantitatively search for cavities generated in the covering body, as compared with the conventional cavitation method that has been empirically performed.

The present invention is not limited to the above-mentioned embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0026]

As described above, according to the present invention, it is possible to detect the presence or absence of a cavity on a quantitative basis in the cavity exploration of a coating such as a mortar slope, which has been conventionally conducted. As a result, the reliability of exploration can be significantly increased. Further, when a cavity is detected, it is possible to detect the depth together with the position thereof, that is, three-dimensional information. Moreover, since the discriminant function of the presence or absence of a cavity and the estimation function of the cavity depth obtained from the detailed data of a part of the target slope can calculate the position and depth of the cavity of the other part,
It has the advantage that exploration work can be performed with high efficiency and low cost, and is extremely effective in repairing or maintaining the slope of the covering.

[Brief description of drawings]

FIG. 1 is a flowchart showing a process of a method for exploring a covered slope of the present invention.

FIG. 2 is a schematic diagram showing a configuration for performing the method of FIG.

FIG. 3 is a graph showing the hit rate of the presence / absence of cavities according to the discriminant function of the present invention.

FIG. 4 is a graph comparing estimated and measured cavity depths of the present invention.

[Explanation of symbols]

 1 Infrared radiation thermometer (infrared radiation temperature detecting means) 2 Data recording device 4 Concrete mortar (cover) 5 Data processing device (data processing means) a Cavity

Claims (1)

[Claims] 1. The surface temperature of the coated body is measured by using infrared radiation temperature detecting means on the slope formed with the coated body on a natural slope, and the obtained temperature data and the state of the coated body slope are observed. A combination of the visually readable data, a discriminant function for detecting the deformed portion of the covering slope by analyzing both of these data by the data processing means, and the depth of the cavity existing between the natural slope and the covering. A method for locating a cavity on a slope of a covering body, characterized by creating an estimation function and determining the position and depth of the cavity based on these functions.