A concrete specimen size detection device and method

Abstract

The present invention discloses a device and method for detecting the size of a concrete specimen. The device comprises a plurality of laser displacement sensors. At least one pair of laser displacement sensors is arranged on each of the four surfaces of the specimen, namely the front, rear, left and right surfaces, and the laser emitting ends on the four surfaces are located on the same horizontal plane and are perpendicular to the surface of the specimen. At least four laser displacement sensors are arranged on each of the upper and lower surfaces of the specimen, and the four laser displacement sensors on each surface are arranged in a square and the intervals between the laser displacement sensors are equal. All the laser displacement sensors on each surface can move linearly on their respective planes at the same time. The device of the present invention can quickly and accurately measure the size and flatness of the specimen, reduce the test cost, and reduce the labor intensity.

Description

Technical Field

[0001] The invention belongs to the technical field of concrete experimental tools, and in particular relates to a concrete specimen size detection device and a concrete specimen size detection method. Background Art

[0002] Concrete is the first to bear pressure in the structure, so its compressive strength index is the most important strength index. The compressive strength of concrete is related to many factors such as the composition material and construction method. It is also affected by factors such as the specimen size, loading method, loading speed, etc. Therefore, there must be a standardized strength measurement method and corresponding strength assessment standards.

[0003] At present, there are two types of concrete specimens used to determine the compressive strength of concrete in the world: cylinder and cube. In my country, cubic specimens are used to measure the compressive strength of concrete and are used as the basis for assessing the strength grade of concrete. Due to the influence of factors such as the height, flatness and cross-sectional area of ​​the specimen, the maximum force value to crush the specimen is different, and the calculated compressive strength value is also different, so it is necessary to accurately measure the size and angle of the specimen.

[0004] At present, most quality inspection agencies use vernier calipers to measure the side length and height of concrete specimens; the flatness of the specimen's pressure-bearing surface is measured using a steel ruler and a feeler gauge. When measuring, the steel ruler is placed upright and horizontally on the specimen's pressure-bearing surface, slowly rotated 360°, and the maximum gap is measured with a feeler gauge as the flatness value; the angle between adjacent surfaces of the specimen is measured using a vernier angle gauge; Disadvantages: high labor intensity, large measurement result errors, low work efficiency, and high cost.

[0005] It can be seen that the specimen size and angle measured manually are affected by human factors and are less scientific and accurate. Summary of the invention

[0006] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a concrete specimen size detection device and method, which can quickly and accurately measure the specimen size and flatness, reduce test costs, reduce labor intensity, and improve test efficiency.

[0007] In order to solve the above technical problems, the present invention provides a concrete specimen size detection device, comprising a plurality of laser displacement sensors;

[0008] At least one pair of the laser displacement sensors is arranged on each of the four surfaces of the test piece, namely, the front, rear, left and right surfaces. All the laser displacement sensors on the four surfaces are located on the same horizontal plane, and each laser displacement sensor on each surface is located on the same vertical plane parallel to the corresponding surface, and the positions of the laser displacement sensors on the opposite surfaces correspond to each other one by one.

[0009] At least four laser displacement sensors are arranged on each of the upper and lower surfaces of the test piece, and the four laser displacement sensors on each surface are located on the same horizontal plane and arranged in a square; all the laser displacement sensors on each surface can move linearly on their respective planes at the same time, and after moving into place, the positions of the laser displacement sensors on the upper and lower surfaces can maintain a one-to-one correspondence;

[0010] The laser displacement sensor is used to collect the distance between itself and the surface of the test piece, and based on the distance, the edge length and the flatness of the upper and lower surfaces of the test piece are obtained.

[0011] Furthermore, the distances between all the laser displacement sensors in the six surfaces of front, rear, left, right, top and bottom and the corresponding test piece surface are equal.

[0012] Furthermore, the distance between all laser displacement sensors on each of the six surfaces, namely, the front, rear, left, right, top and bottom, and the surface facing the specimen is 65-135 mm.

[0013] Furthermore, the distance between a pair of laser displacement sensors on each of the four surfaces, namely, the front, rear, left and right, is equal.

[0014] Furthermore, the distance between a pair of laser displacement sensors on each of the four surfaces, namely, the front, rear, left and right surfaces, is 100 mm.

[0015] Furthermore, the distance between the laser displacement sensors on each of the upper and lower surfaces is 80 mm.

[0016] Accordingly, a detection method based on the concrete specimen size detection device includes:

[0017] Collect data from the laser displacement sensors on each surface of the specimen to obtain the distance between each laser displacement sensor and the corresponding specimen surface;

[0018] Based on the distances between the corresponding laser displacement sensors on the opposite surfaces of the specimen and the distances between each laser displacement sensor and the corresponding surface of the specimen, the length of each edge of the specimen is calculated;

[0019] All laser displacement sensors on each of the upper and lower surfaces are linearly moved simultaneously on their respective planes, and the sensors stop at multiple positions during the movement process. The data of all laser displacement sensors on the upper and lower surfaces at each stop position are collected to obtain the distance between each laser displacement sensor and the upper and lower surfaces of the specimen.

[0020] Based on the distances between the corresponding laser displacement sensors on the upper and lower surfaces of the specimen and the distances between each laser displacement sensor and the upper and lower surfaces of the specimen, the flatness of the upper and lower surfaces of the specimen is calculated.

[0021] Furthermore, the length of each edge of the specimen is calculated based on the distance between the corresponding laser displacement sensors on the opposite surfaces of the specimen and the distance between each laser displacement sensor and the corresponding surface of the specimen, including:

[0022] Taking the calculation of the length of the edge between the left and right sides of the specimen as an example, the pair of laser displacement sensors on the left are denoted as L1 and L2, and the distances from the specimen surface measured by L1 and L2 are data A and data B. The pair of laser displacement sensors on the right are denoted as R1 and R2, and the distances from the specimen surface measured by R1 and R2 are data C and data D.

[0023] If data A is close to data B, and data C is close to data D, then the specimen is correctly placed:

[0024] Get the horizontal distance between L1 and R1, subtract data A and C from this horizontal distance, and the result is the length of the edge between the left and right surfaces;

[0025] Get the horizontal distance between L2 and R2, subtract data B and D from this horizontal distance, and the result is the length of the other side edge sandwiched by the left and right faces;

[0026] If data A is close to data D, and data B is close to data C, then the specimen is judged to be tilted:

[0027] Obtain the horizontal distance between L1 and L2. This horizontal distance and data A and B form a right-angled trapezoid. Calculate the inner angle of this right-angled trapezoid, that is, the inclination angle on the test surface of the specimen, according to trigonometric functions.

[0028] Get the horizontal distance between L1 and R1. This distance minus data A and C is the sine function of the edge length of the specimen. The edge length of one side sandwiched by the left and right faces is calculated using trigonometric functions.

[0029] Similarly, the length of the edge between the left and right faces can be calculated.

[0030] Furthermore, the moving process stops at at least three locations.

[0031] Further, the calculation of the flatness of the upper and lower surfaces of the specimen based on the distance between the corresponding laser displacement sensors on the upper and lower surfaces of the specimen and the distance between each laser displacement sensor and the surface of the specimen includes:

[0032] Take the calculation of the flatness of the specimen as an example to describe:

[0033] When staying at the first position, based on the distance between each laser displacement sensor and each measuring point on the surface of the specimen, the coordinates of each measuring point on the surface of the specimen can be known, and the plane with the smallest sum of the squares of the distances between each measuring point and a certain surface is defined as the reference plane;

[0034] The distance between each measuring point and the reference plane is the flatness of the specimen surface. The arithmetic mean of the corresponding flatness of the four measuring points is taken as the single flatness value.

[0035] Similarly, calculate the flatness values ​​of the other two positions;

[0036] Finally, the arithmetic mean of the flatness of the three positions is taken as the flatness of the plane.

[0037] Compared with the prior art, the beneficial effects achieved by the present invention are: the dimension detection device of the present invention measures accurately and with high precision, reduces the test cost, reduces the labor intensity, and improves the test efficiency. The detection method of the present invention is fast and accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 It is a structural schematic diagram of the device of the present invention;

[0039] Figure 2 is a schematic diagram of the flatness measurement principle.

[0040] Figure numerals: 1. laser displacement sensor, 2. test piece. DETAILED DESCRIPTION

[0041] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0042] In the description of the patent of the present invention, it should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, which includes not only the listed elements but also other elements not explicitly listed.

[0043] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal connection of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0045] A concrete specimen size detection device of the present invention, see Figure 1 As shown, it includes a plurality of laser displacement sensors 1, each of which includes a laser emitting end and a laser receiving end;

[0046] At least one pair of laser displacement sensors 1 is arranged on each of the four surfaces, front, back, left and right, of the specimen 2. All laser displacement sensors on each surface are at the same distance from the surface of the specimen, with a distance range of 65 to 135 mm, for example, 80 mm in this embodiment, and the distances between the laser displacement sensors on the four surfaces are equal, for example, 100 mm in this embodiment. The laser emitting ends on the four surfaces, front, back, left and right, are located on the same horizontal plane (after the position of the emitting end is determined, the position of the receiving end is also determined accordingly), and are perpendicular to the surface of the specimen.

[0047] At least four laser displacement sensors 1 are arranged on each of the upper and lower surfaces of the specimen 2. The four sensors on the upper and lower surfaces are arranged in a square, and the spacing between the sensors is equal, for example, 100 mm in this embodiment; all laser emitting ends on each surface are on the same horizontal plane, and the distance from the surface of the specimen is equal (the distance range is 65~135mm, for example, 80mm in this embodiment). The upper and lower laser displacement sensors move linearly on the upper and lower planes. They will stay at at least three positions during the movement. The four sensors on the upper and lower positions can correspond one to one.

[0048] A concrete specimen size detection device according to the present invention has a specimen size measurement process as follows: before the test, the horizontal distance (i.e., no-load distance) between the two corresponding pairs of laser displacement sensors on the opposite side surfaces is measured first; after the specimen is placed in the middle of the measuring device, during measurement, the laser beam emitted by each laser emitting end on each side surface is reflected by the specimen surface and then received by the laser receiving end to detect the horizontal distance (i.e., load distance) between the laser displacement sensor and the end surface of the specimen; the no-load distance minus the corresponding load distances on both sides is the side length of the specimen.

[0049] The working process of the laser displacement sensors on the left and right sides is described in detail as an example. There are two groups of symmetrically arranged laser displacement sensors on the left and right sides. The pair of laser displacement sensors on the left are denoted as L1 and L2. The distances from the surface of the specimen measured by L1 and L2 are data A and B. The pair of laser displacement sensors on the right are denoted as R1 and R2. The distances from the surface of the specimen measured by R1 and R2 are data C and D.

[0050] I) Determination of the side length of the specimen:

[0051] 1) The specimen is placed correctly

[0052] If data A is close to data B, and data C is close to data D, then it is judged that the specimen is placed correctly.

[0053] The horizontal distance between L1 and R1 is constant and known. The data A and C are subtracted from this horizontal distance, and the result is the length of the edge on one side sandwiched by the left and right sides. The horizontal distance between L2 and R2 is constant and known. The data B and D are subtracted from this horizontal distance, and the result is the length of the edge on the other side sandwiched by the left and right sides. And so on, the length of each edge of the specimen is obtained by measuring once.

[0054] 2) Place the test block at an angle

[0055] Since the laser displacement sensors L1 and L2, or R1 and R2, on the same surface are in a straight line, theoretically, if data A is close to data D, and data B is close to data C, it can be determined that the specimen is skewed.

[0056] The distance between L1 and L2 is constant, and this distance forms a right-angled trapezoid with data A and B. The inner angle of this right-angled trapezoid, that is, the inclination angle on the surface to be tested of the specimen, can be calculated according to trigonometric functions. This inner angle can be obtained 4 times on the front, back, left and right surfaces. By comparing these four values, the angle values ​​of the four surfaces can be determined. The following example uses the same four values ​​to calculate the edge length of the specimen:

[0057] The distance between L1 and R1 is constant. The sine function of the edge length of the specimen is obtained by subtracting data A and C from this distance. The length of the edge on one side sandwiched by the left and right faces can be obtained by trigonometric calculation. The lengths of other edges can be obtained in the same way.

[0058] If the internal angles of the right trapezoids mentioned above are different, calculate the difference. According to the trigonometric formula, the corresponding edge length of the specimen can also be obtained.

[0059] II) Determination of flatness:

[0060] The four sensors on the top and bottom are arranged in a square, with equal spacing between the sensors; the vertical distance between the sensors and the test piece is consistent. The upper and lower laser displacement sensors will stop at three positions respectively during the linear movement on the upper and lower planes. The four sensors on the top and bottom of each position can correspond one by one.

[0061] The calculation principle of the flatness of the upper and lower surfaces is the same. In the embodiment of the present invention, the calculation of the flatness of the upper surface of the test piece is taken as an example. When staying in the first position, refer to Figure 2 As shown, assuming that the plane where each laser displacement sensor on the upper surface is located is plane I, and the real plane of the specimen surface is III, the distance between each laser displacement sensor and each measurement point (ABCD) on the specimen surface is known, and the coordinates of each measurement point on the specimen surface are known. The plane with the smallest sum of the squares of the distances from each measurement point to a certain surface is defined as the reference plane, that is, Figure 2 Midplane II.

[0062] The distance between each measuring point and the reference plane (i.e. the absolute value of the deviation between the distance between planes I and II and the distance measured by the laser displacement sensor) is the flatness of the specimen surface. Then the arithmetic mean of the corresponding flatness of the four measuring points is taken as the single flatness value.

[0063] Similarly, calculate the flatness values ​​of the other two positions. The final arithmetic mean is the flatness of the plane (upper surface).

[0064] After the specimen size is measured, those with qualified size will be subjected to concrete compression test, while those with unqualified size will be placed in the unqualified sample box.

[0065] The size detection device of the present invention has accurate measurement and high precision, reduces test costs, reduces labor intensity, and improves test efficiency.

[0066] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A detection method for a concrete specimen size detection device, characterized in that the concrete The test piece size detection device includes a number of laser displacement sensors; At least one pair of the laser displacement sensors is arranged on each of the four surfaces of the test piece, namely, the front, rear, left and right surfaces. All the laser displacement sensors on the four surfaces are located on the same horizontal plane, and each laser displacement sensor on each surface is located on the same vertical plane parallel to the corresponding surface, and the positions of the laser displacement sensors on the opposite surfaces correspond to each other one by one. At least four laser displacement sensors are arranged on each of the upper and lower surfaces of the test piece, and the four laser displacement sensors on each surface are located on the same horizontal plane and arranged in a square; all the laser displacement sensors on each surface can move linearly on their respective planes at the same time, and after moving into place, the positions of the laser displacement sensors on the upper and lower surfaces can maintain a one-to-one correspondence; The laser displacement sensor is used to collect the distance between itself and the surface of the test piece, and based on this distance, obtain the edge length and the flatness of the upper and lower surfaces of the test piece; A detection method for a concrete specimen size detection device, comprising: Collect data from the laser displacement sensors on each surface of the specimen to obtain the distance between each laser displacement sensor and the corresponding specimen surface; Based on the distances between the corresponding laser displacement sensors on the opposite surfaces of the specimen and the distances between each laser displacement sensor and the corresponding surface of the specimen, the length of each edge of the specimen is calculated; All laser displacement sensors on each of the upper and lower surfaces are linearly moved simultaneously on their respective planes, and the sensors stop at multiple positions during the movement process, and data of all laser displacement sensors on the upper and lower surfaces are collected at each stop position, so as to obtain the distance between each laser displacement sensor and the upper and lower surfaces of the specimen; Based on the distances between the corresponding laser displacement sensors on the upper and lower surfaces of the specimen and the distances between each laser displacement sensor and the upper and lower surfaces of the specimen, the flatness of the upper and lower surfaces of the specimen is calculated; The method of calculating the length of each edge of the test piece based on the distance between the corresponding laser displacement sensors on the opposite surfaces of the test piece and the distance between each laser displacement sensor and the corresponding test piece surface comprises: Taking the calculation of the length of the edge between the left and right sides of the specimen as an example, the pair of laser displacement sensors on the left are denoted as L1 and L2, and the distances from the specimen surface measured by L1 and L2 are data A and data B. The pair of laser displacement sensors on the right are denoted as R1 and R2, and the distances from the specimen surface measured by R1 and R2 are data C and data D. If data A is close to data B, and data C is close to data D, then the specimen is correctly placed: Get the horizontal distance between L1 and R1, subtract data A and C from this horizontal distance, and the result is the length of the edge between the left and right surfaces; Get the horizontal distance between L2 and R2, subtract data B and D from this horizontal distance, and the result is the length of the other side edge sandwiched by the left and right faces; If data A is close to data D, and data B is close to data C, then the specimen is judged to be tilted: Obtain the horizontal distance between L1 and L2. This horizontal distance and data A and B form a right-angled trapezoid. Calculate the inner angle of this right-angled trapezoid, that is, the inclination angle on the test surface of the specimen, according to trigonometric functions. Obtain the horizontal distance between L1 and R1. The result obtained by subtracting data A and C from this distance is equal to the hypotenuse length of the right triangle formed by the edge of the specimen and the inner angle of the right trapezoid; calculate the length of the edge of one side sandwiched by the left and right faces according to trigonometric functions; Similarly, the length of the other side edge between the left and right faces can be calculated.

2. The detection method of a concrete specimen size detection device according to claim 1, characterized in that: The distances between all laser displacement sensors in the six surfaces of front, rear, left, right, top and bottom and the corresponding test piece surface are equal.

3. The detection method of a concrete specimen size detection device according to claim 2, characterized in that: The distance between all the laser displacement sensors on each of the six surfaces, namely, the front, rear, left, right, top and bottom, and the surface of the test piece is 65-135 mm.

4. The detection method of a concrete specimen size detection device according to claim 1, characterized in that: The distance between a pair of laser displacement sensors on each of the four surfaces, namely, the front, rear, left and right, is equal.

5. The detection method of the concrete specimen size detection device according to claim 4 is characterized in that: The distance between a pair of laser displacement sensors on each of the four surfaces, namely, the front, rear, left and right surfaces, is 100 mm.

6. The detection method of a concrete specimen size detection device according to claim 1, characterized in that: The distance between the laser displacement sensors on each of the upper and lower surfaces is 80 mm.

7. The detection method of a concrete specimen size detection device according to claim 1, characterized in that: The step of stopping at at least three positions during the moving process.

8. A detection method for a concrete specimen size detection device according to claim 7, characterized in that: The method of calculating the flatness of the upper and lower surfaces of the specimen based on the distances between the corresponding laser displacement sensors on the upper and lower surfaces of the specimen and the distances between each laser displacement sensor and the upper and lower surfaces of the specimen comprises: Take the calculation of the flatness of the upper surface of the specimen as an example to describe: When staying at the first position, based on the distance between each laser displacement sensor and each measuring point on the upper surface of the test piece, the coordinates of each measuring point on the upper surface of the test piece can be known, and the plane with the smallest sum of the squares of the distances between each measuring point and a certain surface is defined as the reference plane; The distance between each measuring point and the reference plane is the flatness of the upper surface of the specimen. The arithmetic mean of the corresponding flatness of the four measuring points is taken as the single flatness value. Similarly, calculate the flatness values ​​of the other two positions; Finally, the arithmetic mean of the flatness of the three positions is taken as the flatness of the upper surface.

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