Method for detecting fineness modulus and grading of sand grains for concrete

Abstract

The invention discloses a concrete sand fineness modulus and grading detection method, which comprises: 1, obtaining a sand sample, and flatly laying the sand sample on a glass slide; 2, determining the amplification factor of a microscope according to the particle size condition of the sand sample; step 3, under the determined magnification of the microscope, carrying out calibration and calibration on microscopic image measurement and analysis software; step 4, collecting an image of the amplified sand grain sample, then identifying particles in the image in microscopic image measurement analysis software, plotting a particle maximum diameter straight line, and measuring the particle diameter to obtain diameter data of the sand grain sample; and 5, calculating the fineness modulus and grading of the sand grain sample according to the diameter data. The detection method disclosed by the invention has the advantages of simplicity in operation, rapidness in detection, high detection accuracy and the like, and is suitable for a concrete mixing company to control the quality of the concrete sand and adjust the concrete proportion in real time according to a fineness detection result.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete, and particularly relates to a method for detecting the fineness modulus and gradation of sand particles for concrete. Background Art

[0002] The gradation of sand particles refers to the matching of sand particles of different sizes. This matching has a direct impact on the density, workability, strength and durability of concrete. Well-graded sand particles, that is, large and small particles fill each other to form a small void ratio, can reduce the amount of cement slurry, increase the density of concrete, and thus improve the strength and durability of concrete. The fineness modulus characterizes the coarseness of sand particles. It reflects the average coarseness of sand particles of different sizes mixed together. The larger the fineness modulus, the coarser the sand. By testing the fineness modulus of sand particles, it is possible to evaluate whether the coarseness of sand particles meets the requirements of concrete preparation, thereby ensuring the quality of concrete. Testing the fineness modulus and gradation of sand particles are key steps to ensure the quality and performance of concrete. Through reasonable gradation and appropriate fineness modulus, concrete with good workability, high strength and strong durability can be prepared.

[0003] Therefore, before using sand to prepare concrete, it is necessary to test the fineness modulus and gradation of the sand in order to control the quality of the sand and adjust the concrete mix ratio in real time according to the fineness test results, thereby ensuring the performance of the prepared concrete. Summary of the invention

[0004] In view of the above problems, the present invention discloses a method for detecting the fineness modulus and gradation of sand particles for concrete, so as to overcome the above problems or at least partially solve the above problems.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] The present invention discloses a method for detecting the fineness modulus and gradation of sand particles for concrete, the method comprising the following steps:

[0007] Step 01, obtaining a sand sample, and spreading the sand sample on a glass slide;

[0008] Step 02, determining the magnification of the microscope according to the particle size of the sand sample;

[0009] Step 03, calibrating the microscopic image measurement and analysis software under the determined magnification of the microscope;

[0010] Step 04, collecting the magnified image of the sand sample, then identifying the particles in the image in the microscopic image measurement and analysis software, plotting the maximum diameter straight line of the particles, and measuring the particle diameter, thereby obtaining the diameter data of the sand sample;

[0011] Step 05, calculating the fineness modulus and gradation of the sand sample according to the diameter data.

[0012] Furthermore, the step 01 is specifically as follows:

[0013] Step 011, using a sampling spoon to dig out a sand sample;

[0014] Step 012, spreading the sand sample on a hard plate;

[0015] Step 013, using transparent tape to stick the sand sample on the hard board;

[0016] Step 014, fixing the transparent tape with the sand sample on a carrier sheet.

[0017] Furthermore, the hard board is square, and the side length of the hard board is not less than 60 mm.

[0018] Furthermore, the transparent tape is square, and the side length of the transparent tape is 14 to 18 mm.

[0019] Furthermore, the side length of the slide is not less than 20 mm.

[0020] Furthermore, the magnification of the microscope is determined according to the particle size of the sand sample as follows:

[0021] When it is visually observed that the diameters of most particles in the sand sample are less than 1 mm, and the diameters of the particles are not much different, an image of the sand sample is collected using a microscope with a magnification of 50X or more;

[0022] When it is visually observed that the diameters of most particles in the sand sample are greater than 1 mm, and the diameters of the particles vary greatly, a microscope with a magnification of 20X or less is used to capture images of the sand sample.

[0023] Furthermore, the calibration of the microscopic image measurement and analysis software is specifically performed as follows:

[0024] The micrometer is placed on the stage of the microscope, the focal length of the microscope is adjusted to make the collected measurement image of the micrometer clear, and the micrometer in the measurement image is marked in the microscopic image measurement and analysis software.

[0025] Furthermore, the measuring range of the micrometer is 0-1 mm, and the accuracy of the micrometer is 0.01 mm.

[0026] Furthermore, the image of the sand sample after acquisition and enlargement is specifically:

[0027] The focal length of the microscope is adjusted so that the microscope can clearly observe the sand grain sample, and then at least three magnified images of the sand grain sample are collected, and each image corresponds to a different area of ​​the sand grain sample.

[0028] The advantages and beneficial effects of the present invention are:

[0029] The detection method of the present invention has the advantages of simple operation, rapid detection and high detection accuracy, and is suitable for concrete mixing companies to control the quality of concrete sand and adjust the concrete mix ratio in real time according to the fineness test results. Moreover, the present invention is compared with the sieve analysis method, and the correlation percentage of the test results of the two methods exceeds 90%, indicating that the detection method of the present invention is accurate and reliable. In addition, the detection method of the present invention can also be used to analyze the content of soil and stone powder particles in the sand, and identify the rock characteristics and particle shape of the sand particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0031] Figure 1 FIG. 1 is a diagram of the implementation steps of a method for detecting the fineness modulus and gradation of sand particles for concrete in one embodiment of the present invention;

[0032] Figure 2 This is an enlarged image of the sand sample collected. DETAILED DESCRIPTION

[0033] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] The technical solutions provided by various embodiments of the present invention are described in detail below in conjunction with the accompanying drawings.

[0035] In one embodiment of the present invention, a method for detecting the fineness modulus and gradation of sand particles for concrete is provided, such as Figure 1 As shown, the detection method comprises the following steps:

[0036] Step 01, obtain a sand sample and spread the sand sample on a glass slide so that each sample particle can be observed through a microscope.

[0037] Step 02, determine the magnification of the microscope according to the particle size of the sand sample, so as to subsequently identify and map the tiny particles in the sand sample.

[0038] Step 03, calibrating the microscopic image measurement and analysis software under the determined magnification of the microscope, wherein the microscopic image measurement and analysis software may be Toup View software.

[0039] It should be noted that the microscope is connected to a computer installed with microscopic image measurement and analysis software, so that the observation content of the microscope can be intuitively displayed on the computer screen, and the image obtained on the computer screen can be made clearer by focusing the microscope.

[0040] Step 04, collect the image of the enlarged sand sample, such as Figure 2 As shown, the particles in the image are identified in the microscopic image measurement and analysis software, and the maximum diameter straight line of the particles is plotted, and the particle diameter is measured to obtain the diameter data of the sand sample, and finally the diameter data is exported from the microscopic image measurement and analysis software. Among them, it can be exported in the form of an EXCEL table.

[0041] Step 05, calculate the fineness modulus and gradation of the sand sample according to the diameter data. The calculation process can be implemented by other software.

[0042] According to the Standard for Quality and Inspection Methods of Sand and Stone for Ordinary Concrete (JGJ52-2006), the detection method of the present invention is compared with the sieve analysis method. The comparison results are shown in Table 1. Although the fineness modulus detected by the two methods is different, the test results are completely consistent, that is, the results of judging the sand particle size are completely consistent; it can be seen that the data correlation percentage of the two test results is greater than 90%.

[0043]

[0044] Table 1

[0045] In summary, the detection method of the present embodiment has the advantages of simple operation, fast detection and high detection accuracy, and can convert the lithology of sand particles that are difficult to distinguish with the naked eye, that is, the attributes reflecting the characteristics of rocks in geology (including but not limited to color (mineral characteristics), rock types (sedimentary rocks, metamorphic rocks, igneous rocks), bedding structure of sand particle rocks, particle size, sedimentary characteristics (these characteristics are related to the firmness and mechanical properties of sand particles), particle morphology (irregular polyhedron with rough surface, ellipsoid with smooth surface, needle-shaped, sheet-shaped, etc.) and geometric dimensions (such as particle diameter)) into accessible computer data in the form of orthographic projection images, which is suitable for concrete mixing companies to control the quality of concrete sand and adjust the concrete mix ratio in real time according to the fineness test results; and, the present invention is compared with the sieve analysis method, and the correlation percentage of the test results of the two exceeds 90%, indicating that the detection method of the present invention is accurate and reliable; in addition, the detection method of the present invention can also be used to analyze the content of soil and stone powder particles in the sand, and identify the rock characteristics and particle shape of the sand particles.

[0046] In this embodiment, step 01 is specifically as follows:

[0047] Step 011, use a sampling spoon to scoop out sand samples.

[0048] Step 012, spread the sand sample on a hard board. The hard board is slightly elastic. The sand sample can be evenly spread on the hard board by lightly tapping the hard board with fingers, so that no particles of the sand sample can be observed with the naked eye. Otherwise, the hard board can be lightly vibrated with fingers so that there is no stacking of the sand sample. During the spreading process, the sand sample must not escape from the hard board to prevent affecting the accuracy of the test results.

[0049] Step 013, use transparent tape to stick to the sand samples on the hard board, and fix the sand samples by transparent tape to prevent the sand from moving or scattering during the detection process; specifically, use single-sided tape to press the adhesive surface onto the above-mentioned sand samples so that all sand samples stick to the tape.

[0050] Step 014, fix the transparent tape with the sand sample on the carrier sheet, specifically, the tape with the sand sample can be turned over by two small tapes and then bonded and fixed on the carrier sheet. Of course, in other embodiments, the sand sample can also be fixed on the carrier sheet in other ways, which are also within the scope of protection of the present invention.

[0051] The hard plate is square, and the side length of the hard plate is not less than 60mm; the transparent tape is square, and the side length of the transparent tape is 14-18mm; the side length of the slide is not less than 20mm. In this way, sufficient sand samples are guaranteed for testing, and the sand samples can be prevented from escaping and scattering.

[0052] If after completing the above steps, there are still sand grain samples on the hard board that have not been picked up by the transparent tape (the remaining sand grain samples may be too small to be stuck to the transparent tape when they were picked up with the transparent tape in the early stage), use transparent tape to pick up the remaining sand grain samples, place them on the carrier sheet and repeat the sample detection operation, so that the sand grain samples with smaller particle sizes can also be identified and plotted, thereby ensuring the accuracy of the detection.

[0053] In addition, the magnification of the microscope is determined according to the particle size of the sand sample:

[0054] When the diameters of most particles in the sand sample are less than 1 mm and the diameters of the particles do not differ much, a microscope with a magnification of 50X or more is used to capture images of the sand sample to ensure that smaller particles can appear clearly in the image, facilitating the identification and mapping of small particles.

[0055] When the diameter of most particles in the sand sample is larger than 1mm and the particle diameters vary greatly, a microscope with a magnification of 20X or less is used to collect images of the sand sample. In this way, the field of view of the microscope is larger, more particles can be observed, and the observed sample is more representative.

[0056] The magnification is determined according to the particle size so that the amount of sand sample in the image is within a reasonable range, thereby enabling more accurate detection of the sand particle fineness modulus and gradation.

[0057] In this embodiment, the microscopic image measurement and analysis software is calibrated as follows:

[0058] Place the micrometer on the stage of the microscope, adjust the focal length of the microscope to make the collected measurement image of the micrometer clear, and mark the micrometer in the measurement image in the microscopic image measurement and analysis software, thereby realizing the calibration of the microscopic image measurement and analysis software.

[0059] It should be noted that different magnifications of the microscope cause the same sand sample to have different sizes in the collected image. In order to ensure accurate measurement of the sand sample at different magnifications of the microscope, it is necessary to calibrate the microscopic image measurement and analysis software at the corresponding magnification of the microscope.

[0060] Among them, the measuring range of the micrometer is 0~1mm, and the accuracy of the micrometer is 0.01mm.

[0061] In addition, the image of the sand sample after the enlargement is specifically as follows:

[0062] Adjust the focal length of the microscope so that the microscope can clearly observe the sand sample, and then collect at least three magnified images of the sand sample, with each image corresponding to a different area of ​​the sand sample, thereby preventing the occurrence of accidental detection and ensuring the accuracy of the test results.

[0063] The above is only a specific embodiment of the present invention. Under the above teachings of the present invention, those skilled in the art can make other improvements or modifications on the basis of the above embodiments. Those skilled in the art should understand that the above specific description is only to better explain the purpose of the present invention, and the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for detecting the fineness modulus and gradation of sand for concrete, characterized in that: The detection method comprises the following steps: Step 01, obtaining a sand sample, and spreading the sand sample on a glass slide; Step 02, determining the magnification of the microscope according to the particle size of the sand sample; Step 03, calibrating the microscopic image measurement and analysis software under the determined magnification of the microscope; Step 04, collecting the magnified image of the sand sample, then identifying the particles in the image in the microscopic image measurement and analysis software, plotting the maximum diameter straight line of the particles, and measuring the particle diameter, thereby obtaining the diameter data of the sand sample; Step 05, calculating the fineness modulus and gradation of the sand sample according to the diameter data.

2. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 1, characterized in that: The step 01 is specifically as follows: Step 011, using a sampling spoon to dig out a sand sample; Step 012, spreading the sand sample on a hard plate; Step 013, using transparent tape to stick the sand sample on the hard board; Step 014, fixing the transparent tape with the sand sample on a carrier sheet.

3. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 2, characterized in that: The hard board is square, and the side length of the hard board is not less than 60 mm.

4. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 2, characterized in that: The transparent tape is square, and the side length of the transparent tape is 14-18 mm.

5. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 2, characterized in that: The side length of the slide is not less than 20 mm.

6. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 1, characterized in that: The magnification of the microscope is determined according to the particle size of the sand sample as follows: When it is visually observed that the diameters of most particles in the sand sample are less than 1 mm, and the diameters of the particles are not much different, an image of the sand sample is collected using a microscope with a magnification of 50X or more; When it is visually observed that the diameters of most particles in the sand sample are greater than 1 mm, and the diameters of the particles vary greatly, a microscope with a magnification of 20X or less is used to capture images of the sand sample.

7. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 1, characterized in that: The calibration of the microscopic image measurement and analysis software is specifically as follows: The micrometer is placed on the stage of the microscope, the focal length of the microscope is adjusted to make the collected measurement image of the micrometer clear, and the micrometer in the measurement image is marked in the microscopic image measurement and analysis software.

8. The method for detecting the fineness modulus and gradation of sand for concrete according to claim 7, characterized in that: The measuring range of the micrometer is 0-1 mm, and the accuracy of the micrometer is 0.01 mm.

9. The method for detecting the fineness modulus and gradation of sand for concrete according to any one of claims 1 to 8, characterized in that: The image of the sand sample after acquisition and enlargement is specifically: The focal length of the microscope is adjusted so that the microscope can clearly observe the sand grain sample, and then at least three magnified images of the sand grain sample are collected, and each image corresponds to a different area of ​​the sand grain sample.

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