A quality evaluation method for color appearance of plain concrete blocks

Abstract

The present invention discloses a quality evaluation method for the color appearance of a clear-faced concrete block, which mainly includes the following steps: first, the surface to be tested of the concrete specimen is divided into zones, and then the color value of each zone is detected, and then the color value of each zone and the color value of standard white are marked in a three-dimensional coordinate system, and the distance between the position of the color value coordinate point of each zone and the position of the color value coordinate point of standard white in the three-dimensional coordinate system is calculated, and the mean value, variance value and / or standard deviation value of each distance value are obtained, and the appearance of the clear-faced concrete block is evaluated using the obtained data value. The test evaluation method provided by the present application does not require the assistance of an external light source during the test, is not restricted by light, and can be tested during the day and at night. It is not restricted by space, and relevant test operations can be carried out as long as personnel can reach the place, the test conditions are low, the operation process is simple, there are fewer human factors, and the test results are highly accurate.

Description

Technical Field

[0001] The invention relates to the field of appearance evaluation methods for fair-faced concrete blocks, and specifically discloses a quality evaluation method for the color appearance of fair-faced concrete blocks. Background Art

[0002] Accurate evaluation of the color appearance of exposed concrete blocks is a key task in measuring the appearance quality of concrete buildings.

[0003] The existing concrete appearance inspection is mainly to take pictures of the appearance of the concrete structure under the same lighting conditions, then use relevant software to process the grayscale of the pictures, and evaluate the color appearance quality of the concrete by the grayscale distribution of the pictures. However, this method has high requirements for photography conditions and the operation process is cumbersome. For example, the requirements of various factors such as the lighting when taking pictures, the shooting angle, or the distance between the camera and the test target, lead to a large influence of human factors in the entire test and evaluation process, and the accuracy of the test results is low. Summary of the invention

[0004] The purpose of the present invention is to provide a quality evaluation method for the color appearance of plain concrete blocks in view of the problems that the test and evaluation methods for the color appearance of plain concrete blocks in the prior art have high test condition requirements, cumbersome operation process, large influence of human factors and low accuracy of test results. The test and evaluation method provided by the present application has low test condition requirements, simple operation process, fewer human influence factors and high accuracy of test results.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A method for evaluating the color appearance of a clear concrete block, characterized by comprising the following steps:

[0007] Step 1: Divide the surface of the concrete block to be tested into a plurality of test areas, and detect the color value of each test area respectively;

[0008] Step 2: Mark the color values ​​of the same type corresponding to the standard white and the groups of color values ​​obtained in step 1 in a three-dimensional coordinate system;

[0009] Step 3, respectively calculate the distance values ​​from the coordinate positions of several groups of color values ​​to the coordinate positions of the standard white color values; obtain the mean values ​​of several groups of distance values, and the variance values ​​and / or standard deviation values ​​of several groups of distance values, and implement the quality evaluation of the color appearance of the plain concrete block based on the obtained data.

[0010] The test and evaluation method for the color appearance of the clear water concrete block disclosed in the present invention mainly includes the following steps: first, the surface to be tested of the concrete specimen is divided into zones, and then the color value of each zone is detected, and then the color value of each zone and the color value of the standard white are marked in a three-dimensional coordinate system, and the distance between the position of the color value coordinate point of each zone and the position of the color value coordinate point of the standard white in the three-dimensional coordinate system is calculated, and the mean value, variance value and / or standard deviation value of each distance value are obtained, and the appearance of the clear water concrete block is evaluated by using the obtained data value. The test and evaluation method provided by the present application does not require the assistance of an external light source during the test, is not restricted by light, and can be tested during the day and at night. It is not restricted by space, and relevant test operations can be carried out as long as personnel can reach the place, the test conditions are low, the operation process is simple, there are fewer human factors, and the test results are highly accurate.

[0011] Furthermore, in step 1, the distance between two adjacent test areas is 5 cm or more. Studies have shown that if the distance between the test areas is too large, the accuracy of the test will be reduced, and if the distance between the test areas is too small, the test workload will be increased, and there will be no significant contribution to the test accuracy. Preferably, in step 1, the distance between two adjacent test areas is 5 cm to 10 cm. More preferably, in step 1, the distance between two adjacent test areas is 5 cm to 8 cm.

[0012] Furthermore, in step 1, a representative area of ​​the surface to be tested of the plain concrete block is selected for testing.

[0013] Furthermore, in step 1, the area of ​​the clear water concrete block is 3m 2 ~5m 2 If the surface to be tested is too large, the number of test points will increase accordingly, the test difficulty will increase, and even an operating platform will be required to assist in the measurement; if the surface to be tested is too small, the data collected will be too little and not representative.

[0014] Furthermore, in step 1, the test area is a circular area with a radius of 3 cm to 5 cm.

[0015] Furthermore, in step 3, the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value) or (L value, a value, b value).

[0016] Furthermore, in step 3, when the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value), the color value coordinates corresponding to the standard white are (255, 255, 255); when the coordinates of the color value in the three-dimensional coordinate system are (L value, a value, b value), the color value coordinates of the standard white are (0, 0, 100).

[0017] Furthermore, in step 3, when the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value), the calculation formula for the distance value from the coordinate position of the plurality of color value groups to the coordinate position of the standard white color value is: Where R is the R value, G is the G value, and B is the B value

[0018] ; When the color value in the three-dimensional coordinate system is (L value, a value, b value), the calculation formula for the distance value from the coordinate position of a number of color value groups to the coordinate position of the standard white color value is: Among them, a is the a value, b is the b value, and L is the L value.

[0019] Furthermore, when the appearances of different plain concrete blocks are compared or the appearances of the same plain concrete block in different time periods are compared, in step 3, the higher the mean of the several groups of distance values ​​obtained, the darker the color of the plain concrete appearance; the larger the standard deviation of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance; the larger the variance of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance.

[0020] Furthermore, in step 3, when the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value), the standard deviation of several groups of distance values ​​obtained is ≤5, and the variance of several groups of distance values ​​obtained is ≤50, which determines that the color appearance uniformity of the plain concrete is excellent.

[0021] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0022] The quality evaluation method of the color appearance of the clear water concrete block disclosed in the present invention mainly includes the following steps: first, the surface to be tested of the concrete specimen is divided into zones, and then the color value of each zone is detected, and then the color value of each zone and the color value of the standard white are marked in a three-dimensional coordinate system, and the distance between the position of the color value coordinate point of each zone and the position of the color value coordinate point of the standard white in the three-dimensional coordinate system is calculated, and the mean value, variance value and / or standard deviation value of each distance value are obtained, and the appearance of the clear water concrete block is evaluated by using the obtained data value. The test evaluation method provided by the present application does not require the assistance of an external light source during the test, is not restricted by light, and can be tested during the day and at night. It is not restricted by space, and relevant test operations can be carried out as long as personnel can reach the place, the test conditions are low, the operation process is simple, there are fewer human factors, and the test results are highly accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 The following are the appearance changes of the plain concrete specimens in Example 1 at different times.

[0024] Figure 2 This is a color value test data diagram of each area in Example 1.

[0025] Figure 3 Schematic diagram of the three-dimensional coordinate system of color values ​​in Example 1. DETAILED DESCRIPTION

[0026] The present invention will be described in detail below in conjunction with the accompanying drawings.

[0027] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] Example 1

[0029] Embodiment 1 provides a method for evaluating the quality of color appearance of a plain concrete block, comprising the following steps:

[0030] Step 1: Figure 1 As shown in the figure, the surface of the concrete block to be tested is divided into several test areas. The test area is a circle with a radius of 4 cm. The several test areas evenly cover the entire test piece. The interval between two adjacent test areas is 5 cm. When the test piece is large, a representative 2m×2m area should be taken for measurement; then the color value (R value, G value, B value) in the middle of each test area is detected respectively, as shown in FIG. Figure 2 As shown;

[0031] Step 2: Mark the color values ​​(R value, G value, B value) obtained in step 1 and the same color value (255, 255, 255) corresponding to the standard white color in the three-dimensional coordinate system, as shown in FIG. Figure 3 As shown;

[0032] Step 3, calculate the distance values ​​from the coordinate positions of several groups of color values ​​to the coordinate positions of the standard white color value in the three-dimensional coordinate system in step 2; obtain the mean of several groups of distance values, and the variance value and / or standard deviation value of several groups of distance values. The test results are shown in Table 1.

[0033] Among them, the distance value

[0034] Four months later, the same test pieces were subjected to the same tests as in steps 1-3. The test results after four months are shown in Table 1.

[0035] Table 1

[0036]

[0037] Figure 1The two photos in the middle are photos of the same test piece taken at different time points. From the left picture, we can see that the overall color of the test piece is relatively uniform. After being placed outdoors for 4 months, the appearance color of the test piece becomes the right picture. From the right picture, we can see that black spots have appeared on the appearance of the test piece and the overall color has darkened. The color uniformity has also decreased compared to the left picture. From the two test data, the mean of the test results is increasing, and the standard deviation and variance are also increasing, which is consistent with the observation results of overall darkening and decreased uniformity.

[0038] When the appearances of different plain concrete blocks are compared or the appearances of the same plain concrete block in different time periods are compared, in step 3, the higher the mean of the several groups of distance values ​​obtained, the darker the color of the plain concrete appearance is; the larger the standard deviation of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance is; the larger the variance of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance is.

[0039] During the test, it is important to note that the test equipment should be close to the test specimen to prevent natural light from entering the test instrument; to find the best partition value, too dense partitions will increase the test workload and have no obvious contribution to the test accuracy, and too sparse partitions will reduce the test accuracy (the interval between two adjacent measuring points should be 5cm-10cm, and when the specimen is large, a representative 2m*2m area should be taken for measurement.)

[0040] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for evaluating the color appearance of a clear concrete block, characterized in that , comprising the following steps: Step 1, dividing the surface to be tested of the plain concrete block into several test areas, respectively detecting the color value of each of the test areas, wherein the distance between two adjacent test areas is 5cm to 10cm; Step 2: Mark the color values ​​of the groups obtained in step 1 and the same color values ​​corresponding to the standard white color in a three-dimensional coordinate system; Step 3, respectively calculating the distance values ​​from the coordinate positions of several groups of color values ​​to the coordinate positions of the standard white color values: obtaining the mean values ​​of several groups of distance values, and the variance values ​​and / or standard deviation values ​​of several groups of distance values, and realizing the quality evaluation of the color appearance of the plain concrete block according to the obtained data; When the appearances of different plain concrete blocks are compared or the appearances of the same plain concrete block in different time periods are compared, in step 3, the higher the mean of the several groups of distance values ​​obtained, the darker the color of the plain concrete appearance is; the larger the standard deviation of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance is; the larger the variance of the several groups of distance values ​​obtained, the worse the color uniformity of the plain concrete appearance is.

2. The method for evaluating the color appearance of a clear concrete block according to claim 1 is characterized in that In the step 1, the area of ​​the surface to be tested of the plain concrete block is 3㎡-~5; the test area is a circular area with a radius of 3cm~5cm.

3. The method for evaluating the color appearance of a clear concrete block according to claim 2 is characterized in that In step 1, the distance between two adjacent test areas is greater than 5 cm.

4. The method for evaluating the color appearance of a clear concrete block according to claim 1 is characterized in that In step 1, the distance between two adjacent test areas is 5 cm to 8 cm.

5. The method for evaluating the color appearance of a clear concrete block according to claim 1 is characterized in that In step 1, the color value is an RGB value or a Lab value; in step 3, the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value) or (L value, a value, b value).

6. The method for evaluating the color appearance of a clear concrete block according to claim 5 is characterized in that In step 3, when the color value coordinates in the three-dimensional coordinate system are (R value, G value, B value), the color value coordinates corresponding to the standard white are (255, 255, 255); when the color value coordinates in the three-dimensional coordinate system are (L value, a value, b value), the color value coordinates of the standard white are (100, 0, 0).

7. The method for evaluating the color appearance of a clear concrete block according to claim 6 is characterized in that In step 3, when the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value), the calculation formula for the distance value from the coordinate position of a plurality of color value groups to the coordinate position of the standard white color value is: ； When the coordinates of the color value in the three-dimensional coordinate system are (L value, a value, b value), the calculation formula for the distance value from the coordinate positions of several groups of color values ​​to the coordinate position of the standard white color value is: 。 8. The method for evaluating the color appearance of a plain concrete block according to claim 1, characterized in that: In step 3, when the coordinates of the color value in the three-dimensional coordinate system are (R value, G value, B value), the standard deviation of several groups of distance values ​​obtained is ≤5, and the variance of several groups of distance values ​​obtained is ≤50, which indicates that the color appearance uniformity of the plain concrete is excellent.

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