A bleeding performance test device for semi-flexible pavement and its usage method

Abstract

The present invention discloses a test device for bleeding performance of semi-flexible pavement, which includes a transparent sleeve, a cross plate, a lower cover, a grille and a pressing rod. The shape of the grille is the same as the cross-section of the inner wall of the sleeve, and the lower cover is detachably connected to the sleeve. It is characterized in that multiple groups of rectangular-shaped clamping holes are longitudinally and parallelly arranged on the upper layer of the outer wall of the sleeve. The bottom of the pressing rod is threadedly connected to the grille. A circular opening is arranged on the outer wall of the sleeve near the bottommost clamping hole, and a water storage device is provided at the bottom of the opening. It can simulate the actual use situation of the slurry, comprehensively consider the fixing and interfering effects of aggregates on the slurry, and the influence of factors such as the dynamic bleeding process on the bleeding characteristics of the slurry, provides a reliable test method for the key indicators of the performance of the semi-flexible pavement slurry, and can effectively improve the quality of pavement engineering.

Description

Technical Field

[0001] The present invention belongs to the field of pavement materials for traffic engineering. More specifically, the present invention relates to a bleeding performance testing device for semi-flexible pavement and a method for using the same. [[ID=S]]Background Art

[0002] Semi-flexible pavement is a kind of pavement material with both rigidity and flexibility formed by pouring a highly fluid cement-based material into a large-void asphalt mixture. It has good rutting resistance and has advantages such as oil resistance and water damage resistance, and is widely used in pavement maintenance or new construction. To ensure pouring, it is required that the slurry has very good fluidity, and its fluidity is usually 10 - 13 s, and the fluidity index is only 2 - 5 s larger than that of water. In addition, the cement-based material is highly sensitive to the use environment temperature, and construction accuracy, especially the water consumption, is very important. When the temperature drops or the water consumption is on the high side, bleeding will occur in the cement-based material. The so-called bleeding refers to the phenomenon of solid-liquid separation that occurs after the cement-based material is mixed with water, which often leads to a certain thickness of water seeping out on the road surface. After the water evaporates due to the lack of cement-based substances, the road surface pouring is not full. Diseases such as chipping and potholes will form under vehicle loads, greatly shortening the service life of the pavement.

[0003] Therefore, the bleeding performance index of the grouting material is a key control factor to ensure the project quality. The close prior art is based on the test method of Specification JTG E30: T0528. However, since the cement-based material in the semi-flexible pavement is poured by the post-pouring method, the asphalt mixture skeleton has a certain interference and fixing effect on the distribution of solid substances in the cement-based material. Therefore, the conventional method for testing the bleeding rate in cement concrete cannot correspond to the actual bleeding situation of the pavement. The conventional method for testing the bleeding rate in cement concrete is to use the method of statically placing the cement slurry and transferring the seeped water for testing. Due to the strong fluidity of the cement slurry used in the semi-flexible pavement, obvious bleeding phenomena are often not visible by this method. However, in actual projects, due to the role of aggregates, after the solid in the fluid cement-based material is poured into the large-void matrix, it is initially fixed by the matrix skeleton, and the seeped water floats on the surface due to its light weight. At this time, workers will use tools to push away the excess water on the surface, but often the light water will float up again, and the bleeding phenomenon continuously occurs dynamically. Therefore, the conventional bleeding performance detection method is a static test, which cannot accurately measure and does not correspond to the actual project.

[0004] The invention with the patent number CN104569023A discloses a method for measuring the bleeding property of cement paste by using low-field nuclear magnetic resonance technology of hydrogen protons. The obtained paste is filled into a test tube that does not interfere with the signal of the nuclear magnetic resonance instrument and left to stand. By testing the transverse relaxation time decay curve and calculating the area, the bleeding coefficient of the cement paste is obtained. For the semi-flexible pavement paste with good fluidity, it is not easy to obtain obvious curve changes by this method, and the data discrimination between water and slurry is not large. In addition, this method cannot simulate the dynamic water-pushing process. The invention with the patent number CN112345737A discloses a method for testing the bleeding rate of cement grouting material suitable for duct grouting, which mainly simulates the actual slurry working condition of duct grouting by pressurization and is not applicable to the situation where there is aggregate interference in semi-flexible materials. Summary of the Invention

[0005] The technical problem to be solved by the present invention is a bleeding performance test device for semi-flexible pavement and its use method for accurately measuring the bleeding rate in actual engineering.

[0006] To achieve the above object, the technical solution adopted by the present invention is: a bleeding performance test device for semi-flexible pavement, including a transparent sleeve, a cross plate, a lower cover, a grille, and a pressing rod. The shape of the grille is the same as the cross-sectional shape of the inner wall of the sleeve, and the lower cover is detachably connected to the sleeve. A plurality of rectangular-shaped clamping holes are longitudinally arranged in parallel on the upper layer of the outer wall of the sleeve. The bottom of the pressing rod is threadedly connected to the grille. A circular opening is provided on the outer wall of the sleeve near the bottommost clamping hole, and a water storage device is provided at the bottom of the opening; the grille is in the shape of a thin sheet, and a plurality of small holes with a diameter of 10-15 mm are provided on the surface of the grille.

[0007] Through the above settings, the fixed buckle connection formed by the clamping holes and the cross plate avoids the problem of pressure imbalance during pouring water, which affects the continuation of subsequent experiments. The threaded connection between the lower cover and the sleeve ensures the quickness of removing the slurry after the experiment and the convenience of cleaning the lower cover; the porous grille is beneficial to the water separation of the slurry.

[0008] For the bleeding performance test device for semi-flexible pavement disclosed by the present invention, the transparent sleeve is made of one of plastic, glass, or resin.

[0009] Through the above settings, it is convenient to directly observe the water separation situation inside the sleeve.

[0010] For the bleeding performance test device for semi-flexible pavement disclosed by the present invention, the pressing rod has various models with different lengths but the same outer diameter.

[0011] Through the above settings, the pressing rod with the corresponding length can be selected according to the strength of the elastic deformation of different slurries, which is applicable to the calculation of the bleeding rate of various slurries.

[0012] A bleeding performance testing device for semi-flexible pavement disclosed by the present invention, wherein the water storage device is a measuring cup or a sample cup.

[0013] A bleeding performance testing device for semi-flexible pavement disclosed by the present invention, wherein the sleeve can be one of a cylinder or a regular polygon.

[0014] Through the above settings, the regular pattern is beneficial to the design of the mold or the programming of the numerical control machine tool, facilitating the production and manufacturing of the sleeve and the grille, and enabling standardized mass production.

[0015] A bleeding performance testing device for semi-flexible pavement disclosed by the present invention, wherein the opening is one of a valve, a faucet or a plug tube.

[0016] Through the above settings, in order to prevent the influence of wind and the external environment, the opening should be closed when the water is not being poured, so a device that is convenient to open and close is selected.

[0017] A method for using a bleeding performance testing device for semi-flexible pavement disclosed by the present invention includes the following steps:

[0018] S1: Pretreatment: Install the lower cover and the sleeve using threads, install the pressing rod and the grille using threads, brush release oil on the inner wall of the sleeve, and pour aggregate into the sleeve.

[0019] S2: Extrusion: Place the grille in the sleeve, raise the pressing rod, and squeeze the grille downward. Insert the cross plate according to the position of the pressing rod, and pour the slurry m1 (g) into the aggregate until the slurry is completely immersed in the aggregate.

[0020] S3: Static precipitation: Observe every 5 minutes whether water is precipitated. If water is precipitated, tilt the sleeve so that the precipitated water flows out of the cylinder through the opening and collect it. Pour it once every 5 minutes to simulate the actual construction process until no water is precipitated on the surface of the slurry.

[0021] S4: Calculate the bleeding rate: Weigh the amount of precipitated water m2 (g), then the bleeding rate of the semi-flexible pavement slurry is:

[0022] V = m1 / m2.

[0023] A method for using a bleeding performance testing device for semi-flexible pavement disclosed by the present invention, wherein the aggregate includes hard aggregate and elastic aggregate. For the hard aggregate, the position of the aggregate can be fixed by extrusion; for the elastic aggregate, a matrix with different void ratios can be obtained by extrusion.

[0024] Adopting the solution of the present invention, compared with the prior art, it has the following beneficial effects:

[0025] 1. It can simulate the actual use situation of the slurry, comprehensively consider the fixing and interfering effects of the aggregate on the slurry, factors such as the dynamic bleeding process, etc. on the bleeding characteristics of the slurry, provide a reliable test method for the key indicators of the semi-flexible pavement slurry performance, and can effectively improve the quality of the pavement project.

[0026] 2. The structure of this device is simple, with a wide range of applications, and can be used in laboratories and specific working environments.

[0027] The present invention will be described in more detail below in conjunction with the drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The following briefly describes the content expressed in each drawing of this specification and the marks in the drawings:

[0029] Figure 1 is a schematic diagram of the present invention;

[0030] Figure 2 is a side view of the present invention;

[0031] Figure 3 is a top view of the present invention;

[0032] The marks in the figure are: 1. Sleeve; 2. Horizontal plate; 3. Pressing rod; 4. Grille; 5. Opening; 6. Card hole; 7. Water storage device; 8. Lower cover; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0033] The following further describes in detail the specific embodiments of the present invention, such as the shapes, structures, mutual positions and connection relationships of the various components involved, the functions and working principles of each part, the manufacturing process and the operation and use methods, etc., in contrast to the drawings, so as to help those skilled in the art have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention.

[0034] Consisting of Figure 1 A test device for the bleeding performance of a semi-flexible pavement shown, including a transparent sleeve (1) made of one of plastic, glass or resin, a horizontal plate (2), a lower cover (8), a thin grille (4) with a plurality of small holes on the surface, and pressing rods (3) with the same outer diameter but different lengths. Among them, the shape of the grille (4) is the same as the cross-section of the inner wall of the sleeve (1), and the lower cover (8) is detachably connected to the sleeve (1). A plurality of groups of rectangular card holes (6) are longitudinally arranged in parallel on the upper layer of the outer wall of the sleeve (1). The bottom of the pressing rod (3) is threadedly connected to the grille (4). A circular opening (5) is arranged near the bottom layer of the card holes (6) on the outer wall of the sleeve (1), and a water storage device (7) similar to a measuring cup or a sample cup is provided at the bottom of the opening (5).

[0035] Embodiment 1

[0036] S1: Pretreatment: Install the lower cover and the sleeve (1) using threads, install the pressure rod (3) and the grille (4) using threads, brush isolation oil on the inner wall of the sleeve (1), and pour aggregate into the sleeve (1).

[0037] S2: Extrusion: Place the grille (4) in the sleeve (1), raise the pressure rod (3), and squeeze the grille (4) downward. Insert the cross plate (2) according to the position of the pressure rod (3), and pour the slurry m1 (g) into the aggregate until the slurry is completely immersed in the aggregate.

[0038] S3: Static water separation: Observe every 5 minutes whether water is separated out. If water is separated out, tilt the sleeve (1) so that the separated water flows out of the cylinder through the opening and collect it; pour it once every 5 minutes to simulate the actual construction process until there is no water separated out on the surface of the slurry.

[0039] S4: Calculate the bleeding rate: Weigh the separated water volume m2 (g), then the bleeding rate of the semi-flexible pavement slurry is: V = m1 / m2.

[0040] Comparative Example 1:

[0041] Adopt the test method of Specification JTG E30: T0528.

[0042] Table 1 Experimental data

[0043]

[0044] As can be seen from Table 1, in Comparative Example 1, the bleeding rate value of the semi-flexible pavement slurry cannot be measured by the traditional method, while the bleeding rate value can be effectively measured by using the device of the present invention. Therefore, from the experimental results of the above examples and comparative examples, it can be seen that the present invention can more accurately measure the bleeding rate value of the semi-flexible pavement slurry.

[0045] The present invention has been described exemplarily above with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited by the above methods. As long as various non-substantive improvements are made by adopting the method concept and technical solution of the present invention, or the concept and technical solution of the present invention are directly applied to other occasions without improvement, they are all within the protection scope of the present invention.

Claims

1. A test device for the bleeding performance of a semi-flexible pavement, comprising a transparent sleeve (1), a cross plate (2), a lower cover (8), a grille (4) and a pressure rod (3), wherein the grille (4) has the same shape as the inner wall cross-section of the sleeve (1), and the lower cover (8) is detachably connected to the sleeve (1), characterized in that, On the outer wall of the sleeve (1), multiple groups of rectangular clamping holes (6) are longitudinally arranged in parallel. The bottom of the pressure rod (3) is threadedly connected to the grille (4). A circular opening (5) is provided on the outer wall of the sleeve (1) near the lowermost clamping hole (6), and a water storage device (7) is provided at the bottom of the opening (5). The grille (4) is in the shape of a thin sheet, and multiple small holes with a diameter of 10-15 mm are provided on the surface of the grille (4).

2. The bleeding performance testing device for semi-flexible pavement according to claim 1, characterized in that, The transparent sleeve (1) is made of one of plastic, glass or resin.

3. The water bleeding performance testing device for semi-flexible pavement according to claim 1, characterized in that, The pressure rod (3) has multiple models with different lengths but the same outer diameter.

4. The bleeding performance testing device for semi-flexible pavement according to claim 1, characterized in that, The water storage device (7) is a measuring cup or a sample cup.

5. The water bleeding performance test device for semi-flexible pavement according to claim 1, characterized in that, The sleeve (1) can be one of a cylinder or a regular polyhedron.

6. The water bleeding performance testing device for semi-flexible pavement according to claim 1, wherein The opening (5) is one of a valve, a faucet or a plug tube.

7. A method for using a bleeding performance testing device for a semi-flexible pavement according to any one of claims 1-6, characterized in that It includes the following steps: S1： Pretreatment: The lower cover and the sleeve (1) are installed using threads, the pressure rod (3) and the grille (4) are installed using threads, the inner wall of the sleeve (1) is brushed with release oil, and aggregate is poured into the sleeve (1). S2: Extrusion: Place the grille (4) in the sleeve (1), lift the pressure rod (3) upward, squeeze the grille (4) downward, insert the cross plate (2) according to the position of the pressure rod (3), and pour the slurry m1 (g) into the aggregate until the slurry is completely immersed in the aggregate. S3: Static water separation: Observe every 5 minutes whether water is separated out. If water is separated out, tilt the sleeve (1) so that the separated water flows out of the cylinder through the opening and collect it. Pour it once every 5 minutes to simulate the actual construction process until no water is separated out on the surface of the slurry. S4: Calculate the bleeding rate: Weigh the separated water volume m2 (g), then the bleeding rate of the semi-flexible pavement slurry is: V = m1 / m2.

8. The usage method of a bleeding performance testing device for semi-flexible pavement according to claim 7, characterized in that, The aggregate includes hard aggregate and elastic aggregate. For the hard aggregate, the position of the aggregate can be fixed by extrusion; for the elastic aggregate, a matrix with different void ratios can be obtained by extrusion.

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