A bitumen ductility tester

Abstract

This invention provides an asphalt ductility tester, relating to the field of asphalt testing technology. It includes a housing, within which a tensile system, a thermal insulation system, and a constant-temperature water supply system are installed. The thermal insulation system comprises a circulating constant-temperature water tank and a water flow isolation inner tank. The water flow isolation inner tank is installed within the circulating constant-temperature water tank, with a circulation gap between them. Water-blocking baffles are installed on the front and rear sides of the circulating constant-temperature water tank, and the circulating constant-temperature water tank slides against the inner side of the water-blocking baffles. Side holes communicating with the circulation gap are provided on both sides of the water-blocking baffles, and a central hole communicating with the water flow isolation inner tank is provided at the bottom of the water-blocking baffles. An inlet and an outlet are respectively installed at the bottom of the circulating constant-temperature water tank. This invention achieves higher temperature control accuracy by raising and lowering the constant-temperature inner tank, connecting and blocking the central hole, thereby changing the water flow state in the water flow isolation inner tank. This integrated testing method simplifies operation.

Description

Technical Field

[0001] This invention relates to the field of asphalt testing technology, specifically to an asphalt ductility meter. Background Technology

[0002] The asphalt ductility test is applicable to determining the ductility of road petroleum asphalt, polymer-modified asphalt, diluted asphalt, and emulsified asphalt residues. Ductility reflects the ability of asphalt to undergo plastic deformation without fracturing under stress. The treated asphalt specimen is placed in an environment with a specified temperature and subjected to tensile operation at a fixed tensile speed until the specimen breaks. The length measured at this point is the asphalt ductility. The larger the ductility value, the better the flexibility of the asphalt and the stronger its resistance to cracking under low temperature and other environments.

[0003] In the asphalt ductility test, the specimen needs to be cooled at room temperature for at least 1.5 hours. Then, the asphalt on the mold at the top is scraped off with a hot scraper to make the asphalt surface flush with the mold surface. After that, the mold and specimen are placed in a constant temperature water bath at a specified temperature and kept warm for 1.5 hours. The constant temperature water bath needs to maintain a constant temperature accuracy of ±0.1℃. However, existing asphalt ductility testers usually use a water-insulated constant temperature water bath to meet the test requirement that the water surface should not be shaken. Therefore, in some colder regions, the structure of the water-insulated constant temperature water bath is difficult to guarantee the insulation accuracy. Therefore, it is necessary to add a new insulated constant temperature water bath. During the tensile test, the insulated specimen is then moved into the ductility tester, which is very troublesome. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an asphalt ductility meter, which solves the problems mentioned in the background section. Technical solution

[0005] To achieve the above objectives, the present invention provides the following technical solution: An asphalt ductility tester includes a housing, within which a tensile system and a thermal insulation system are installed. The thermal insulation system includes a circulating constant-temperature water tank and a water flow isolation inner tank. The circulating constant-temperature water tank is fixed to the housing, and the water flow isolation inner tank is installed inside the circulating constant-temperature water tank with a circulation gap between them. A lifting mechanism is installed at the bottom of the housing, comprising a lifting cylinder and a stress transmission frame. The stress transmission frame passes through the circulating constant-temperature water tank and connects to the bottom of the water flow isolation inner tank. Water-proof baffles are installed on the front and rear sides of the circulating constant-temperature water tank, and the circulating constant-temperature water tank slides against the inner side of the water-proof baffles. Side holes communicating with the circulation gap are provided on both sides of the water-proof baffles, and a central hole communicating with the water flow isolation inner tank is provided at the bottom of the water-proof baffles. An inlet and an outlet are respectively installed at the bottom of the circulating constant-temperature water tank, and the inlet and outlet are connected to a constant-temperature water supply system.

[0006] Preferably, the stretching system includes a drive motor, a drive screw, and a stretching bracket. A transmission pulley connects the drive motor and the drive screw. A screw nut is fixed on the stretching bracket and threadedly connected to the drive screw. A guide rail parallel to the drive screw is provided on the housing. The stretching bracket is slidably mounted on the guide rail. The end of the stretching bracket is bent downward and disposed in the water flow isolation inner groove. Several test molds are mounted on the stretching bracket.

[0007] Preferably, the test mold consists of two arc-shaped end molds and two side molds. The arc-shaped end molds have end mold holes, and the end mold holes of the two arc-shaped end molds are respectively fixed to the inner wall of the circulating constant temperature water tank and the tension bracket.

[0008] Preferably, the constant temperature water supply system includes a water storage tank, a chiller unit, and a heater. The water storage tank is provided with an outlet pipe and a return pipe connected to the inlet and outlet. The heater is installed between the outlet pipe and the inlet. Beneficial effects

[0009] This invention provides an asphalt ductility meter. It has the following beneficial effects: 1. In this invention, the lifting and lowering of the stress transfer frame allows the water flow isolation inner tank to move up and down within the circulating constant temperature water tank, enabling the connection and disconnection between the water flow isolation inner tank and the central hole. During the curing and heat preservation stage, the water flow isolation inner tank is connected to the central hole, and the constant temperature water in the circulating constant temperature water tank enters the water-blocking baffle through the side hole, and then flows into the water flow isolation inner tank through the central hole, achieving constant temperature water flow and maintaining the temperature of the water flow isolation inner tank at all times, thus improving the accuracy of curing and heat preservation. During the tensile test, the water flow isolation inner tank is isolated from the central hole, stopping the water flow in the water flow isolation inner tank and providing a stable water surface environment for the tensile test. In the static state of the water flow, heat is transferred between the water in the circulating constant temperature water tank and the water flow isolation inner tank, maintaining a precise and constant temperature, avoiding interference with the test, realizing integrated testing, and avoiding the influence of moving the sample on the test results. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the structure of an asphalt ductility tester according to the present invention; Figure 2 This is a schematic diagram of the constant temperature water supply system in this invention; Figure 3 This is a schematic diagram of the thermal insulation system in this invention; Figure 4 This is a cross-sectional view of the asphalt ductility tester in this invention; Figure 5 This is a schematic diagram of the tensioning system in this invention; Figure 6This is a schematic diagram of the circulating constant temperature water tank in this invention; Figure 7 for Figure 6 Enlarged view of a portion of point A in the middle.

[0011] In the diagram: 1. Shell; 2. Circulating constant temperature water bath; 3. Water flow isolation inner tank; 4. Lifting cylinder; 5. Stress transmission frame; 6. Water-proof baffle; 7. Side hole; 8. Central hole; 9. Water storage tank; 10. Chiller unit; 11. Heater; 12. Outlet water pipe; 13. Return water pipe; 14. Drive motor; 15. Drive screw; 16. Tension bracket; 17. Screw nut; 18. Guide rail; 19. Trial mold. Detailed Implementation

[0012] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0013] This invention provides an asphalt ductility tester, such as... Figure 1-7 As shown, it includes a housing 1, and a tensioning system, a constant temperature water supply system and a heat preservation system are installed inside the housing.

[0014] like Figure 3-4 As shown, the insulation system includes a circulating constant-temperature water tank 2 and a water flow isolation inner tank 3. The circulating constant-temperature water tank 2 is fixed to the shell 1. An inlet and an outlet are respectively installed at the bottom of the circulating constant-temperature water tank 2. The inlet is located on the front side of the circulating constant-temperature water tank 2, and the outlet is located on the rear side. Constant-temperature water enters the circulating constant-temperature water tank 2 through the inlet, forming a circulating constant-temperature water flow within the circulating constant-temperature water tank 2 to improve the insulation effect. A circulation gap is provided between the water flow isolation inner tank 3 and the circulating constant-temperature water tank 2. The water will flow within the circulation gap. The water flow isolation inner tank 3 is installed inside the circulating constant temperature water tank 2. The bottom of the housing 1 is fixed with a mounting base. A lifting mechanism is installed on the mounting base. The lifting mechanism includes a lifting cylinder 4 and a stress transmission frame 5. The lifting cylinder 4 is fixed to the lower side of the mounting base. The stress transmission frame 5 is connected to the cylinder 4 arm of the lifting cylinder 4. The stress transmission frame 5 passes through the circulating constant temperature water tank 2 and is connected to the bottom of the water flow isolation inner tank 3. The extension and retraction of the lifting cylinder 4 can pull the water flow isolation inner tank 3 to slide up and down the circulating constant temperature water tank 2.

[0015] like Figure 6-7As shown, water-blocking baffles 6 are installed on the front and rear sides of the circulating constant temperature water tank 2. The water-blocking baffles 6 and the front side of the circulating constant temperature water tank 2 form a circulation space. The water inlet and outlet are respectively located in the circulation space on the front and rear sides. The circulating constant temperature water tank 2 slides and abuts against the inner sides of the two water-blocking baffles 6. Side holes 7 communicating with the circulation gap are provided on both sides of the water-blocking baffles 6. The bottom of the water-blocking baffles 6 is provided with a central hole 8 communicating with the water flow isolation inner tank 3. The constant temperature water will first circulate in the space and then be discharged through the side holes 7 and the central hole 8 respectively. When the constant temperature is raised or lowered... When the water tank slides down and connects with the central hole 8, some of the constant temperature water will flow in the lifting constant temperature water tank to maintain the temperature in a circulating manner. This can provide smaller temperature fluctuations and improve the temperature control accuracy. Some hot water flows out from the side hole 7 and enters the circulation gap to maintain the temperature consistency inside and outside the lifting constant temperature water tank and avoid temperature changes caused by the forward movement of heat transfer. During the tensile test, the lifting constant temperature water tank is controlled to rise until the bottom of the lifting constant temperature water tank is higher than the central hole 8. The constant temperature water can only flow through the circulation gap and maintain the temperature by water-insulating heating, providing stable water surface conditions for the tensile test.

[0016] like Figure 2 As shown, the constant temperature water supply system includes a water storage tank 9, a circulating water pump, a chiller unit 10, and a heater 11. The water storage tank 9 is provided with an outlet pipe 12 and a return pipe 13 connected to the inlet and outlet. The heater 11 is installed between the outlet pipe 12 and the inlet. An installation gap is provided between the housing 1 and the bottom of the circulating constant temperature water tank 2. The outlet pipe 12 and the return pipe 13 extend to the front and rear sides of the circulating constant temperature water tank 2, respectively. In this application, the chiller unit 10 and the heater 11 are used to maintain the temperature stability of the constant temperature water by counteracting temperature control, so as to avoid the constant temperature water from being too hot or too cold.

[0017] like Figure 3 , Figure 5 As shown, the stretching system includes a drive motor 14, a drive screw 15, and a stretching bracket 16. A transmission pulley connects the drive motor 14 and the drive screw 15. A screw nut 17 is fixed on the stretching bracket 16 and threadedly connected to the drive screw 15. A guide rail 18 parallel to the drive screw 15 is provided on the housing 1. The stretching bracket 16 is slidably mounted on the guide rail 18. The end of the stretching bracket 16 is bent downward and placed in the water flow isolation inner groove 3. Several test molds 19 are installed on the stretching bracket 16. Each test mold 19 consists of two arc-shaped end molds and two side molds. The arc-shaped end molds have end mold holes. The end mold holes of the two arc-shaped end molds are respectively fixed to the inner wall of the circulating constant temperature water tank 2 and the stretching bracket 16.

[0018] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. An asphalt ductility tester, comprising a housing, characterized in that: The housing is equipped with a tensioning system and a thermal insulation system. The thermal insulation system includes a circulating thermostatic water tank and a water flow isolation inner tank. The circulating thermostatic water tank is fixed to the housing, and the water flow isolation inner tank is installed inside the circulating thermostatic water tank with a circulation gap between them. A lifting mechanism is installed at the bottom of the housing, which includes a lifting cylinder and a stress transmission frame. The stress transmission frame passes through the circulating thermostatic water tank and connects to the bottom of the water flow isolation inner tank. Water-proof baffles are installed on the front and rear sides of the circulating thermostatic water tank, and the circulating thermostatic water tank slides against the inner side of the water-proof baffles. Side holes communicating with the circulation gap are provided on both sides of the water-proof baffles, and a central hole communicating with the water flow isolation inner tank is provided at the bottom of the water-proof baffles. An inlet and an outlet are respectively installed at the bottom of the circulating thermostatic water tank, and the inlet and outlet are connected to a thermostatic water supply system.

2. The asphalt ductility tester according to claim 1, characterized in that: The stretching system includes a drive motor, a drive screw, and a stretching bracket. A transmission pulley connects the drive motor and the drive screw. A screw nut is fixed on the stretching bracket and threadedly connected to the drive screw. A guide rail parallel to the drive screw is provided on the housing. The stretching bracket is slidably mounted on the guide rail. The end of the stretching bracket is bent downward and placed in a water flow isolation inner groove. Several test molds are mounted on the stretching bracket.

3. The asphalt ductility tester according to claim 2, characterized in that: The test mold consists of two arc-shaped end molds and two side molds. The arc-shaped end molds have end mold holes, and the end mold holes of the two arc-shaped end molds are respectively fixed to the inner wall of the circulating constant temperature water tank and the tension bracket.

4. The asphalt ductility tester according to claim 3, characterized in that: The constant temperature water supply system includes a water storage tank, a chiller unit, and a heater. The water storage tank is equipped with an outlet pipe and a return pipe connected to the inlet and outlet. The heater is installed between the outlet pipe and the inlet.

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