A pouring device and method for preventing stratification phenomenon in pouring concrete specimens

Abstract

The invention discloses a casting device and a casting method for preventing the stratification phenomenon of concrete specimen casting. The casting device comprises a bracket, a sample chamber is installed inside the bracket, a vibration motor and a rotating motor are installed on the bracket, the sample chamber is connected to the power output shaft of the vibration motor through a first connecting rod, and the sample chamber is installed on the power output shaft of the rotating motor through a second connecting rod; the sample chamber comprises a sample box and a top cover, an air cavity is opened in the top cover, a plurality of air holes connected to the air cavity are opened at the lower end of the top cover, a plurality of first telescopic devices and a second telescopic device are installed on two opposite side walls in the sample box, and the telescopic ends of the telescopic devices are fixedly connected to the first movable plate and the second movable plate respectively. By changing the casting device and casting process of conventional concrete specimens, the casted concrete specimens well overcome the problem of coarse and fine aggregates and cement stratification, and more truly reflect the real engineering characteristics of concrete.

Description

Technical Field

[0001] The invention belongs to the technical field of civil engineering, and in particular relates to a casting device and a casting method for preventing the stratification phenomenon during casting of a concrete specimen. Background Art

[0002] The preparation of concrete specimens is an indispensable part in the scientific research of civil engineering construction and design structural engineering. However, since the equipment for casting specimens has not been replaced, the performance of the concrete material itself is not truly reflected. The existing concrete specimen casting equipment consists of several steel plates, and the test mold is relatively old and rough. The casting process requires the sample preparation to be completed through processes such as loading, vibrating and standing. In the process of preparing concrete specimens, there is often a significant concrete stratification problem, which cannot truly reflect the actual engineering characteristics of concrete. Summary of the invention

[0003] The invention provides a casting device and a casting method for preventing the stratification phenomenon of concrete specimen casting, which can effectively prevent the obvious stratification phenomenon of concrete specimen during the casting and molding process, and solve the serious stratification problem of coarse and fine aggregates after sampling that is common in general concrete casting equipment.

[0004] To achieve the above-mentioned purpose, the present invention discloses a casting device for preventing stratification during casting of concrete specimens, comprising a base, wherein the base comprises a bottom plate and a bracket fixed on the bottom plate, a sample chamber, a vibration motor and a rotating motor are installed on the bracket, the sample chamber is connected to the power output shaft of the vibration motor through a first connecting rod, and the sample chamber is installed on the power output shaft of the rotating motor through a second connecting rod; the sample chamber comprises a sample box and a top cover, the top cover has an air cavity, a plurality of air holes connected to the air cavity are opened at the lower end of the top cover, a plurality of first telescopic devices and a second telescopic devices are installed on two opposite side walls in the sample box, and the telescopic ends of the telescopic devices are fixedly connected to the first movable plate and the second movable plate respectively.

[0005] Furthermore, the first telescopic device and the second telescopic device are both hydraulic telescopic rods.

[0006] Furthermore, a side wall of the sample chamber connected to the vibration motor and a side wall of the sample chamber connected to the rotation motor are provided with a thickened layer.

[0007] Furthermore, the thickened layer includes four trapezoidal reinforcement steel plates of the same size and shape, the bottom edges of the four trapezoidal reinforcement steel plates are respectively fixedly connected to the four edges of the side walls of the sample chamber, and the top edges are respectively fixed to the four edges of the square steel plates. A threaded hole is opened at the center of the square steel plate, and the threaded hole is used to screw in a first connecting rod or a second connecting rod with a thread, thereby connecting the sample chamber to the vibration motor or the rotating motor.

[0008] Furthermore, the first movable plate and the second movable plate are both made of steel plates with a thickness of 5mm-8mm.

[0009] Furthermore, the top cover is hinged to the sample box through a hinge, and snap bolts are installed on the top cover.

[0010] Furthermore, a waterproof membrane is installed on the surface of the top cover in contact with the sample box and on the inner wall of the sample box.

[0011] A method for pouring a concrete specimen based on the pouring device for preventing the stratification phenomenon during pouring of a concrete specimen comprises the following steps:

[0012] Step 1: Pour the mixed concrete into the sample chamber, turn on the vibration motor for 30s to 60s and then turn it off, then cover the top cover and tighten the buckle bolts;

[0013] Step 2: Start the rotating motor and rotate the sample chamber 180 degrees so that the top cover faces downward; start the vibration motor for 30s to 60s;

[0014] Step 3: Repeat step 2 until the concrete is vibrated;

[0015] Step 4, squeeze the concrete in the sample chamber so that the excess concrete will be pushed into the air cavity reserved in the top cover;

[0016] Step 5, start the rotating motor, so that the rotating motor drives the sample chamber to rotate until the final setting time position of the concrete is reached, and the concrete specimen production is completed.

[0017] Furthermore, before step 1, a layer of oil is applied to all inner walls of the sample chamber.

[0018] Compared with the prior art, the present invention has at least the following beneficial technical effects:

[0019] The present invention relates to a concrete pouring device and method for pouring concrete to overcome the stratification problem. By changing the pouring device and pouring process of conventional concrete specimens, the concrete specimens obtained by pouring well overcome the stratification problem of coarse and fine aggregates and cement, and more truly reflect the real engineering properties of concrete. The present invention is complete in composition. By changing the equipment for pouring concrete and the pouring process, the concrete specimens completely change the stratification problem that has always existed in the past.

[0020] Furthermore, a side wall of the sample chamber connected to the vibration motor and a side wall connected to the rotation motor are provided with a thickened layer, and the thickened layer can prevent the sample chamber from being damaged during vibration or rotation.

[0021] Furthermore, the first movable plate and the second movable plate are both made of steel plates with a thickness of 5mm-8mm, which have a certain force while ensuring that the telescopic rod can push them to move.

[0022] Furthermore, a waterproof membrane is installed on the surface of the top cover in contact with the sample box and the inner wall of the sample box, and the waterproof membrane can prevent concrete from leaking out.

[0023] A method for casting concrete specimens based on the above-mentioned casting device for preventing the stratification phenomenon during the casting of concrete specimens, during the preparation process of the specimens, multiple vibrations and rotations are performed to effectively prevent the stratification problem of coarse and fine aggregates and cement, so that the prepared specimens can more truly reflect the actual engineering properties of concrete.

[0024] Furthermore, before step 1, a layer of oil is applied to all inner walls of the sample chamber to prevent the concrete from being completely connected and unable to be separated after hardening. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is an overall schematic diagram;

[0026] Figure 2 It is a schematic diagram of the concrete test chamber;

[0027] Figure 3 It is a schematic diagram of the threads of the reinforcing steel plates on both sides.

[0028] In the accompanying drawings: 1. bottom plate, 2. vibration motor, 3. rotating motor, 4. sample chamber, 5. first connecting rod, 6. second connecting rod, 7. top cover, 8. cavity, 9. air hole, 10. bracket, 11. reinforcing steel plate, 12. snap bolt, 13. hinge, 14. first movable plate, 15. second movable plate, 16. first hydraulic telescopic rod, 17. second hydraulic telescopic rod, 41. first side wall, 42. first side wall. DETAILED DESCRIPTION

[0029] In order to make the purpose and technical solution of the present invention clearer and easier to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. The specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0030] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying 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 limiting the present invention. In addition, the terms "first" and "second" are used only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 communication 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.

[0031] Reference Figure 1 A pouring device for preventing stratification during pouring of concrete specimens includes a base, a vibration motor 2, a rotating motor 3, a sample chamber 4, a top cover 7, a first movable plate 14, a second movable plate 15, a first hydraulic telescopic rod 16 and a second hydraulic telescopic rod 17.

[0032] The base is made of steel, and includes a bottom plate 1 and a bracket 10. The bracket 10 is a frame structure, which is convenient for observing and loading and unloading the sample chamber. The bracket 10 includes a first vertical rod, a first horizontal rod, a second vertical rod, and a second horizontal rod, which are fixedly connected end to end in sequence. The first horizontal rod is fixed to the bottom plate by rivets 18, and the upper ends of the first vertical rod and the second vertical rod are respectively fixedly connected to the two ends of the second horizontal rod. The sample bracket 10 is used to place a concrete specimen chamber. A first connecting rod is fixed to the inner side of the first vertical rod, and a second connecting rod is fixed to the inner side of the second vertical rod. A sample chamber 4 is installed between the first connecting rod and the second connecting rod. Mounting holes are provided on the outer sides of the first vertical rod and the second vertical rod, a vibration motor is installed on the outer side of the first vertical rod, and a rotating motor 2 is installed on the outer side of the second vertical rod.

[0033] Reference Figure 2The sample chamber 4 includes a sample box and a top cover 7, which enclose a cavity 8 for containing fresh concrete; the sample box includes a first side wall 41, a second side wall, a third side wall 42 and a fourth side wall which are fixedly connected end to end in sequence, and a bottom plate fixed at the lower ends of the first to fourth side walls. The first to fourth side walls and the bottom plate are made of steel plates. Among them, the first and third side walls are thickened and reserved with threaded holes for connecting screws. There is stress concentration at the threaded connection, and the thickening is to prevent the sample chamber 4 from being damaged during vibration or rotation; the top cover 7 is located directly above the sample box and is hinged to the sample box through a hinge 13. A snap bolt 12 is installed on the other side of the top cover 7 to fix the top cover 7 after pouring.

[0034] Reference Figure 3 Four trapezoidal reinforcement steel plates 11 of the same size and shape are fixed on the first side wall. The bottom edges of the four trapezoidal reinforcement steel plates 11 are fixedly connected to the four sides of the first side wall, and the top edges are fixed to the four sides of the square steel plate 19. A threaded hole 20 is opened at the center of the square steel plate 19. The threaded hole is used to screw in the first connecting rod 5 and the second connecting rod 6 with threads, so as to connect the sample chamber 4 with the vibration motor 2 and the rotating motor 3. During the vibration and rotation process, the first side wall and the third side wall mold are easily damaged by vibration and bending moment, and reinforcement can prevent this from happening.

[0035] A first movable plate 14 and a second movable plate 15 are arranged in the sample box. Both the first movable plate 14 and the second movable plate 15 are made of steel plates with a thickness of 5mm-8mm. Both the first movable plate 14 and the second movable plate 15 are parallel to the first side wall. The first movable plate 14 is located on the side close to the first side wall 41, and the second movable plate 15 is located on the side close to the third side wall 42. The first movable plate is connected to the first side wall through a plurality of first hydraulic telescopic rods 16. One end of the hydraulic telescopic rod is fixedly connected to the first side wall 41 of the sample chamber 4, and the other end is connected to the first movable side plate, so that the distance between the movable side plate and the left side plate of the sample chamber 4 can be controlled by the hydraulic telescopic rod. The second movable plate 15 is connected to the third side wall 42 through the second hydraulic telescopic rod 17. One end of the hydraulic telescopic rod is fixedly connected to the third side wall 42 of the sample chamber 4, and the other end is connected to the third movable side plate.

[0036] The first hydraulic telescopic rod is arranged on the inner wall of the first side wall, and the second hydraulic telescopic rod is arranged on the inner wall of the third side wall. The first hydraulic telescopic rod is used to apply force to the first movable plate, and the second hydraulic telescopic rod is used to apply force to the second movable plate. Each movable plate needs to be evenly provided with four hydraulic assists to ensure that the movable plate does not deform during the propulsion process.

[0037] The vibration motor is connected to the first connecting rod, and the first connecting rod is connected to the vibration motor through a bearing to prevent the vibration motor from rotating when the rotating motor is running. The first connecting rod is connected to the sample chamber through a threaded connection. It is used to vibrate the concrete after the concrete is poured. The vibration motor mainly generates a left-right cycle and transmits the cyclic vibration to the sample chamber 4 through the left connecting rod, thereby achieving a vibration effect.

[0038] A second connecting rod is installed on the power output shaft of the rotating motor 2, and the second connecting rod and the concrete sample chamber 4 are fixedly connected by threads, which is used to rotate the concrete sample chamber 4 after the concrete is poured, so as to prevent the concrete in the sample from being delaminated.

[0039] An air cavity 71 is provided in the top cover 7, and a plurality of air holes 9 communicating with the air cavity 71 are provided at the lower end of the top cover 7 for containing concrete entering through the reserved holes on the first and second movable plates on both sides under the push of the hydraulic device.

[0040] Concrete leakage may occur during the vibration and rotation of the concrete, as well as the movement of the left and right side plates. The place where the top cover 7 contacts the sample box, the end surface where the first movable plate contacts the sample chamber 4, and the end surface where the second movable plate contacts the sample chamber 4 are all installed with waterproof diaphragms, which can prevent concrete leakage.

[0041] The method for pouring a concrete specimen using the above device comprises the following steps:

[0042] Step 1, connect the sample box with the top cover 7, and apply oil to all the inner walls of the sample chamber 4. The oil applied can be determined according to actual needs. Motor oil or vaseline can be used to prevent the concrete from being completely connected and unable to be separated after hardening; connect the sample chamber 4 with the left second connecting rod and fix it on the base, and then install and connect the vibration motor and the rotating motor respectively.

[0043] Step 2, pour the mixed concrete into the sample chamber 4, turn on the vibration motor for 1 minute and then turn it off, then cover the top cover 7 and tighten the snap bolts 12, start the rotating motor, and rotate the sample chamber 4 180° so that the top cover 7 faces downward;

[0044] Step 3, start the vibration motor for 1 minute to transmit the vibration to the sample chamber 4 to achieve the effect of compacting the concrete; start the rotation motor to rotate the sample chamber 4 180° to prevent the gravel and sand in the concrete from sinking in one direction, thereby avoiding stratification in the sample.

[0045] Step 4: Repeat step 3 three times until the concrete is vibrated.

[0046] Step 5, start the first hydraulic telescopic rod and the second hydraulic telescopic rod, so that the first movable plate and the second movable plate move inwards towards each other to squeeze the concrete, and the excess concrete will be pushed into the top cover air cavity 71 reserved by the top cover 7. The main function of this process is to prevent the problem of gas in the concrete specimen or the concrete specimen being insufficient in size. When the hydraulic telescopic rod is pushed forward by about 3mm, the hydraulic telescopic rod can be closed, and it can be ensured that there are no obvious bubbles or missing parts on the surface of the concrete after forming.

[0047] Step 6, start the rotating motor 3, so that the rotating motor 3 drives the sample chamber 4 to rotate until the final setting time position of the concrete is reached, and the concrete specimen production is completed.

[0048] Step 7, remove the vibration motor, the rotating motor and the sample chamber 4 respectively, open the top cover 7, retract the first movable plate and the second movable plate, take out the concrete specimen, and clean the sample chamber 4.

[0049] The above contents are only for explaining the technical idea of ​​the present invention and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution in accordance with the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A pouring device for preventing stratification during pouring of concrete specimens, characterized in that: The base comprises a base, the base comprising a bottom plate (1) and a bracket (10) fixed on the bottom plate (1); a sample chamber (4), a vibration motor (2) and a rotary motor (3) are mounted on the bracket (10); the sample chamber (4) is connected to the power output shaft of the vibration motor (2) via a first connecting rod (5); and the sample chamber (4) is mounted on the power output shaft of the rotary motor (3) via a second connecting rod (6); The sample chamber (4) comprises a sample box and a top cover (7), wherein the top cover (7) has an air cavity (71) therein, and a plurality of air holes (9) communicating with the air cavity are formed at the lower end of the top cover (7), and a plurality of first telescopic devices and second telescopic devices are installed on two opposite side walls in the sample box, and the telescopic ends of the telescopic devices are fixedly connected to the first movable plate (14) and the second movable plate (15) respectively; The first telescopic device and the second telescopic device are both hydraulic telescopic rods; A side wall of the sample chamber (4) connected to the vibration motor (2) and a side wall of the sample chamber (4) connected to the rotation motor (3) are provided with a thickened layer; The thickening layer comprises four trapezoidal reinforcing steel plates (11) of the same size and shape, the bottom edges of the four trapezoidal reinforcing steel plates (11) are respectively fixedly connected to the four sides of the side wall of the sample chamber (4), and the top edges are respectively fixed to the four sides of the square steel plate (19), and a threaded hole (20) is opened at the center of the square steel plate (19), and the threaded hole (20) is used to screw in a first connecting rod (5) or a second connecting rod (6) with a thread, so as to connect the sample chamber (4) to the vibration motor (2) or the rotation motor (3); The top cover (7) is hingedly connected to the sample box via a hinge (13), and a snap bolt (12) is installed on the top cover (7).

2. A pouring device for preventing stratification during pouring of concrete specimens according to claim 1, characterized in that: The first movable plate (14) and the second movable plate (15) are both made of steel plates with a thickness of 5 mm to 8 mm.

3. A pouring device for preventing stratification during pouring of concrete specimens according to claim 1, characterized in that: A waterproof diaphragm is installed on the surface of the top cover (7) in contact with the sample box and on the inner wall of the sample box.

4. A method for casting a concrete specimen based on the casting device for preventing the stratification phenomenon of concrete specimen casting according to any one of claims 1 to 3, characterized in that: The following steps are involved: Step 1, pour the mixed concrete into the sample chamber (4), turn on the vibration motor for 30s to 60s and then turn it off, then cover the top cover (7) and tighten the snap bolts (12); Step 2, start the rotating motor (3), rotate the sample chamber (4) 180 degrees so that the top cover (7) faces downward; start the vibration motor for 30s to 60s; Step 3: Repeat step 2 until the concrete is vibrated; Step 4, squeezing the concrete in the sample chamber (4) so ​​that the excess concrete is pushed into the air cavity (71) reserved in the top cover (7); Step 5: Start the rotating motor (3), so that the rotating motor (3) drives the sample chamber (4) to rotate until the final setting time of the concrete is reached, thereby completing the preparation of the concrete specimen.

5. The method for pouring concrete specimens according to claim 4, characterized in that: Before step 1, apply a layer of oil on all inner walls of the sample chamber (4).

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