Automatic measuring device for density and water absorption rate of coarse aggregate

Abstract

The utility model discloses a coarse aggregate density and water absorption automatic measuring device which comprises a supporting frame, a weighing device, a first motor and a second motor are sequentially arranged on the upper surface of the supporting frame, a hanging basket is arranged on a lifting hook of the weighing device and arranged in a water bath box, a water inlet is formed in one side wall of the water bath box, and a water outlet is formed in the other side wall of the water bath box. A vibrating device is arranged on the upper surface of the water storage tank, the vibrating device is arranged below the first motor, a rotary telescopic rod is arranged at the output end of the first motor, a wiping device is arranged at the end of the rotary telescopic rod, an opening is formed in the side wall, aligned to the wiping device, of the water storage tank, a rotating disc is arranged on the opening, and the rotating disc is connected with a second motor; and an air heater is arranged in the water storage tank, is aligned with the opening and is connected with the second motor. The device solves the problems of complicated operation, time consumption, poor accuracy and the like in the conventional coarse aggregate density and water absorption rate measurement process, and provides guarantee for ensuring the pavement performance.

Description

Technical Field

[0001] The utility model belongs to the technical field of road engineering test equipment, and in particular relates to an automatic measuring device for density and water absorption rate of coarse aggregate. Background Art

[0002] For coarse aggregate used in road engineering, it is very important to measure its density before it is put into use. The density of coarse aggregate will directly affect the design of the mixture ratio. In common asphalt pavement, the relative density measurement value of aggregate greatly affects the accuracy of a series of volume indicators such as the theoretical maximum relative density and porosity of the asphalt mixture. Therefore, the density measurement of coarse aggregate is very important. At present, the conventional method for measuring the density and water absorption of coarse aggregate is a manual method. This method requires manual scooping of water during measurement, and the waiting time for drying is long, which is not only time-consuming and laborious; in addition, there are many human factors in the operation process, which will directly lead to poor accuracy of the experimental results.

[0003] In view of the problems existing in the existing measurement methods, although document CN114354435A discloses a rapid testing device and method for coarse aggregate density and water absorption, it still has problems such as complex structure, inconvenient operation, easy loss of coarse aggregate, and inconvenience in cleaning, which need further improvement. Utility Model Content

[0004] Technical problems solved: In response to the above technical problems, the utility model provides an automatic measuring device for the density and water absorption of coarse aggregate, which uses the inertia principle to spin out most of the water in the aggregate, and combines the drying method to remove the remaining water in the aggregate, thereby achieving rapid drying of the aggregate. It can effectively solve the problems of cumbersome operation, time-consuming and poor accuracy in the process of measuring the density and water absorption of coarse aggregate, and provide a guarantee for ensuring the performance of the pavement.

[0005] Technical solution: An automatic testing device for density and water absorption of coarse aggregate, comprising a support frame, the upper surface of which is sequentially provided with a weighing device, a first motor and a second motor, a hanging basket is provided on the hook of the weighing device, the hanging basket is placed inside a water bath, a water inlet is provided on one side wall of the water bath, and a water outlet is provided on the other side wall, the water outlet is connected to a water storage tank, a vibration device is provided on the upper surface of the water storage tank, the vibration device is arranged below the first motor, a rotating telescopic rod is provided at the output end of the first motor, a drying device is provided at the end of the rotating telescopic rod, an opening is provided on the side wall of the water storage tank aligned with the drying device, a rotating disk is provided on the opening, the rotating disk is connected to the second motor, a hot air blower is provided in the water storage tank, the hot air blower is aligned with the opening, and the hot air blower is connected to the second motor.

[0006] Preferably, a plurality of drainage holes are provided on the side and bottom of the hanging basket; and four centrally symmetrical holes are provided on the upper side of the hanging basket for connecting with a hook or a rotating disk of a weighing device.

[0007] Furthermore, during the drying operation, the side walls of the drying device are placed in the hanging basket.

[0008] Furthermore, the inner side surface of the rotating disk is provided with protrusions that match the holes of the hanging basket, and a wire mesh is provided between the rotating disk and the hanging basket, and the wire mesh is connected to the inner side wall of the hanging basket by a bayonet.

[0009] Preferably, the water bath is connected to the water storage tank via a drainage pipe, and a valve is provided on the drainage pipe.

[0010] Preferably, the drying device is a hollow cylinder, the side wall of the hollow cylinder is provided with an interlayer, four springs are evenly arranged inside the interlayer, and the bottom of the hollow cylinder is connected to the absorbent cloth through the spring.

[0011] Beneficial effects: When measuring the density and water absorption rate of coarse aggregate, the utility model device mainly uses automation and mechanization, avoiding human factors in the measurement process, and can effectively solve the problems of cumbersome operation, time-consuming and poor accuracy in the conventional coarse aggregate density and water absorption rate measurement process, thereby ensuring the scientific nature of the subsequent mixture proportion design and road performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of a coarse aggregate density and water absorption rate automatic measuring device of the utility model;

[0013] Figure 2 It is a structural schematic diagram of the utility model hanging basket;

[0014] Figure 3 It is a structural schematic diagram of the utility model drying device;

[0015] Figure 4 It is a structural schematic diagram of the assembly of the hanging basket and the rotating disk of the utility model;

[0016] Serial numbers in the figure: 1. weighing device, 2. water inlet, 3. water bath, 4. hanging basket, 4-1. hole, 4-2. drain hole, 5. first motor, 6. second motor, 7. water storage tank, 8. rotating telescopic rod, 9. drying device, 9-1. spring, 9-2. absorbent cloth, 9-3. interlayer, 10. drainage pipe, 11. valve, 12. rotating disk, 12-1. protrusion, 12-2. wire mesh, 13. support frame, 14. hot air blower, 15. vibration device. DETAILED DESCRIPTION

[0017] The technical solution of the utility model is further described in detail below in conjunction with the accompanying drawings.

[0018] Example 1

[0019] Reference Figure 1 , an automatic measuring device for density and water absorption of coarse aggregate, comprising a support frame 13, the upper surface of which is sequentially provided with a weighing device 1, a first motor 5 and a second motor 6, a hanging basket 4 is provided on the hook of the weighing device 1, the hanging basket 4 is placed inside a water bath 3, a water inlet 2 is provided on one side wall of the water bath 3, and a water outlet is provided on the other side wall, the water outlet is connected to a water storage tank 7 through a drainage pipe 10, and a valve 11 is provided on the drainage pipe 10, which is conducive to adjusting the water level and saving water; a vibrating device 15 is provided on the upper surface of the water storage tank 7, the vibrating device The device 15 is arranged below the first motor 5, and the output end of the first motor 5 is provided with a rotating telescopic rod 8, and the first motor 5 is used to drive the rotating telescopic rod 8 to extend and rotate 360°; the end of the rotating telescopic rod 8 is provided with a drying device 9, and the water storage tank 7 is provided with an opening on the side wall aligned with the drying device 9, and the opening is provided with a rotating disk 12, and the rotating disk 12 is connected to the second motor 6. A hot air blower 14 is provided in the water storage tank 7, and the hot air blower 14 is aligned with the opening, and the hot air blower 14 is connected to the second motor 6. The hot air blower 14 dries the drying device 9 while drying the coarse aggregate.

[0020] like Figure 2 As shown: the hanging basket 4 is made of stainless steel, and a plurality of drainage holes 4-2 are provided on the side and bottom of the hanging basket 4, the diameter of which is smaller than the particle size of the coarse aggregate; four centrally symmetrical holes 4-1 are provided on the upper side of the hanging basket 4, which are used to connect with the hook or rotating disk 12 of the weighing device 1. During the drying operation, the side wall of the drying device 9 is placed in the hanging basket 4. Figure 4 As shown: the inner side of the rotating disk 12 is provided with a protrusion 12-1 that matches the hole 4-1 of the hanging basket 4, and a wire mesh 12-2 is provided between the rotating disk 12 and the hanging basket 4. The wire mesh 12-2 is connected to the inner wall of the hanging basket 4 by a bayonet to prevent the aggregate from being thrown off during the rotating dehydration process.

[0021] like Figure 3 As shown: the drying device 9 is a hollow cylinder, the side wall of the hollow cylinder is provided with an interlayer 9-3, four springs 9-1 are evenly arranged inside the interlayer 9-3, and the bottom of the hollow cylinder is connected to the absorbent cloth 9-2 through the spring 9-1.

[0022] Example 2

[0023] Using the device of Example 1, under the condition of water temperature of 4°C, the coarse aggregate is measured for mass in water, surface dry mass and oven-dried mass, and density is calculated, and the process is as follows:

[0024] Step 1: Mass measurement in water: first put the water-saturated coarse aggregate into the hanging basket 4, then put the hanging basket 4 into the water bath 3 and hang it on the hook of the weighing device 1, adjust the water level through the water inlet 2 and the valve 11, and after it stabilizes, use the weighing device 1 to measure the mass of the coarse aggregate in water to 301.7g;

[0025] Step 2: Surface dry mass measurement: The hanging basket 4 is fixed on the vibrating device 15 directly below the drying device 9, and the first motor 5 is used to control the extension of the rotating telescopic rod 8 so that the edge of the drying device 9 coincides with the hanging basket 4, and then the rotating telescopic rod 8 drives the drying device 9 to complete the surface drying operation of the coarse aggregate, and then the rotating telescopic rod 8 is shortened to take out the coarse aggregate, and the surface dry mass is measured by the weighing device 1 to be 478.1g;

[0026] Step 3: Drying quality measurement: Place the hanging basket 4 sideways, evenly put the coarse aggregate into it, clamp the wire mesh 12-2 on the top, and then connect the hanging basket 4 with the coarse aggregate to the rotating disk 12 sideways, so that the protrusion 12-1 inside the rotating disk 12 is aligned with the hole 4-1 of the hanging basket 4, and finally use the second motor 6 to control the rotating disk 12 to drive the hanging basket 4 and the coarse aggregate inside to rotate at a constant speed of 360 degrees, and start the hot air blower 14 at the same time. After the coarse aggregate is dried, take it out and measure its drying quality 466.7g;

[0027] Step 4: The density and water absorption of coarse aggregate are calculated according to the following formula:

[0028]

[0029]

[0030]

[0031] Where: γ a is the apparent relative density of aggregate, which is 2.828 when substituted into the calculation;

[0032] γ s is the relative density of aggregate surface dryness, which is 2.710 when substituted into the calculation;

[0033] γ b is the relative density of the aggregate volume, which is 2.646 when substituted into the calculation;

[0034] m a is the drying mass of aggregate, g;

[0035] m f is the surface dry mass of aggregate, g;

[0036] m w is the mass of aggregate in water, g;

[0037]

[0038] Where: w x is the water absorption rate of aggregate (%);

[0039] ρ a =γ a ×ρ T or a =(γ a -α T )×ρ w (5)

[0040] ρ s =γ s ×ρ T or s =(γ s -α T )×ρ w (6)

[0041] ρ b =γ b ×ρ T or =(γ b -α T )×ρ w (7)

[0042] ρ a is the apparent density of aggregate, g / cm 3 , 2.828 g / cm 3 ;

[0043] ρ s is the surface dry density of aggregate, g / cm 3 , substituted into the calculation, we get 2.710g / cm 3 ;

[0044] ρ b is the bulk density of aggregate, g / cm 3 , 2.646 g / cm 3 ;

[0045] ρ T is the density of water at the test temperature T, g / cm 3 ;

[0046] α T is the water temperature correction coefficient at the test temperature T;

[0047] ρ wis the density of water at 4°C, i.e. 1.000 g / cm 3 .

[0048] The embodiments of this specific implementation method are all preferred embodiments of the utility model, and are not intended to limit the protection scope of the utility model. Therefore, all equivalent changes made based on the structure, shape, and principle of the utility model should be included in the protection scope of the utility model.

Claims

1. An automatic measuring device for density and water absorption of coarse aggregate, characterized in that: It includes a support frame, the upper surface of which is sequentially provided with a weighing device, a first motor and a second motor, a hanging basket is provided on the hook of the weighing device, the hanging basket is placed inside a water bath, a water inlet is provided on one side wall of the water bath, and a water outlet is provided on the other side wall, the water outlet is connected to a water storage tank, a vibration device is provided on the upper surface of the water storage tank, the vibration device is arranged below the first motor, a rotating telescopic rod is provided at the output end of the first motor, a drying device is provided at the end of the rotating telescopic rod, an opening is provided on the side wall of the water storage tank aligned with the drying device, a rotating disk is provided on the opening, the rotating disk is connected to the second motor, a hot air blower is provided in the water storage tank, the hot air blower is aligned with the opening, and the hot air blower is connected to the second motor.

2. The automatic measuring device for density and water absorption of coarse aggregate according to claim 1, characterized in that: A plurality of drainage holes are provided on the side and bottom of the hanging basket; and four centrally symmetrical holes are provided on the upper part of the side of the hanging basket for connecting with the hook or rotating disk of the weighing device.

3. The automatic measuring device for density and water absorption of coarse aggregate according to claim 2, characterized in that: During the drying operation, the side walls of the drying device are placed in the hanging basket.

4. The automatic measuring device for density and water absorption of coarse aggregate according to claim 2, characterized in that: The inner side surface of the rotating disk is provided with protrusions which match the holes of the hanging basket. A steel wire mesh is provided between the rotating disk and the hanging basket. The steel wire mesh is connected with the inner side wall of the hanging basket by a bayonet.

5. The automatic measuring device for density and water absorption of coarse aggregate according to claim 1, characterized in that: The water bath is connected to the water storage tank via a drainage pipe, and a valve is provided on the drainage pipe.

6. The automatic measuring device for density and water absorption of coarse aggregate according to claim 1, characterized in that: The drying device is a hollow cylinder, the side wall of the hollow cylinder is provided with an interlayer, four springs are evenly arranged inside the interlayer, and the bottom of the hollow cylinder is connected to the water-absorbing cloth through the spring.

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