Device and method for measuring communication porosity of asphalt mixture test piece

Abstract

The invention provides a device for measuring the communication porosity of an asphalt mixture test piece, which comprises: a cylindrical container, the upper end of which is open, and the container is used for placing normal temperature water and completely placing a measured test piece; the axis of the communicating pipe is arranged on one side of the container in parallel, two ends of the communicating pipe are open, one end is communicated with the bottom of the peripheral surface of the container, and the other end is flush with or higher than the end surface of the container; scale marks are marked on the communicating pipe in the length direction of the communicating pipe. A worker puts enough normal-temperature water into a container, reads the height h1 of a communicating pipe after the horizontal plane is static, then gently puts a measurement test piece into the container to enable the measurement test piece to be completely immersed in the container, reads the water level height h2 of the communicating pipe at the moment after the water level is static, and knows that an object sinks into the water according to the Archimedes theorem. The volume of the discharged water is the volume of the object, and finally, the communicated porosity is calculated through # imgabs0 #.

Description

Technical Field

[0001] The present invention generally relates to the field of large-porosity pavement materials, and particularly relates to a device and method for measuring the connected void ratio of asphalt mixture specimens. Background Art

[0002] Semi-flexible pavement materials are pavement materials formed by pouring cement mortar with special properties into a matrix asphalt mixture with high-connected large voids (void ratio between 20% and 35%). Semi-flexible pavements combine the flexibility of asphalt concrete pavements and the rigidity of cement concrete pavements. Their characteristics are having good rutting resistance while having better integrity and lower rigidity than cement concrete pavements.

[0003] And the connected porosity of asphalt mixture is one of the main indicators. Currently, the detection methods for the connected porosity of asphalt mixture are complex and diverse, and there is no unified regulation in domestic specifications. There is only one local standard. We take DB 11 / T 1817-2021 "Technical Specification for the Design and Construction of Grouted Semi-flexible Pavement Paving Layer" as an example. The formulas are: VVc =

(V - Vm) / V

[0004] In the existing procedures, it is necessary to first measure the mass m a of the specimen in air by a hanging basket balance, and then measure the mass m w of the specimen in water by the hanging basket below. Calculate the volume Vm of the mixture and the closed pores through the formula, and then find VVc through the formula. Since the hanging basket balance has many components and the instrument is relatively precise, and the on-site environment is changeable, such as some dust in the air, it will affect the final measurement accuracy of the specimen, and the operation is cumbersome. Summary of the Invention

[0005] In view of the problems existing in the above-mentioned prior art according to the present invention, a device for measuring the connected void ratio of asphalt mixture specimens is provided, including: a container, which is cylindrical and has an open upper end for completely placing the specimens to be measured; a connecting pipe, whose axis is arranged parallel to one side of the container, and both ends of the connecting pipe are open, one end is interconnected with the bottom of the container circumference, and the other end is flush with or higher than the end face of the container; scale lines are marked on the connecting pipe along its own length direction. With the above technical features, the staff puts enough normal temperature water into the container. After the water level is stationary, the height of the connecting pipe is read as h1. Then, the specimen to be measured is gently placed into the container so that the specimen to be measured is completely immersed in the container. After the water level is stationary, the water level height h2 of the connecting pipe is read at this time. According to Archimedes' theorem, when an object sinks into water, the volume of the water it displaces is the volume of the object. Through the formula D is the inner diameter of the container, and D1 is the inner diameter of the connecting pipe; the volume of the solid part and the closed pore part of the specimen is obtained. Finally, through the connected porosity is calculated. The device is simple while simplifying the operation difficulty and reducing error interference. Using a cylindrical container, the formula can be easily used to calculate V 排 and the connected porosity is calculated according to the standard specimen.

[0006] In some embodiments, a water stop valve is further provided at the connection between the container and the connecting pipe. Thus, the staff can control the water stop valve according to the specific use situation of the container, and when the container is filled with normal temperature water, the damage to the connecting pipe caused by water flow impact is reduced. The staff can adjust the size of the water inlet of the connecting pipe, which plays a protective role for the connecting pipe.

[0007] In some embodiments, the water stop valve is fixedly connected to the bottom of the circumferential surface of the container, and the bottom end of the connecting pipe is detachably and fixedly connected to the port of the water stop valve. Thus, the connecting pipe is set to be detachably and fixedly connected to the container, which is convenient for the staff to transport the container and the connecting pipe separately, improves the safety of the device during transportation, and if the connecting pipe is damaged, it is also convenient to replace the connecting pipe immediately, improving the replacement efficiency.

[0008] In some embodiments, the diameter of the connecting pipe is set to a pipe body greater than or equal to 3 mm and less than or equal to 10 mm. Thus, the diameter of the connecting pipe is restricted, thereby improving the accuracy of the liquid level reading. The thinner the diameter, the more accurate the reading. However, to avoid the occurrence of capillary phenomena, the minimum range is restricted to more than 3 mm.

[0009] In some embodiments, the scale accuracy of the circumferential surface of the connecting pipe is a pipe body greater than 0.5 mm. Thus, the accuracy of the final reading is improved, and the final measurement error is reduced.

[0010] In some embodiments, the container is a cylindrical vessel made of a transparent material. Thus, the staff can visually compare the liquid level heights in the container and the connecting pipe to avoid large-scale experimental errors.

[0011] In some embodiments, a fixator for assisting in fixing the connecting pipe is installed at the port of the container. The fixator includes a connecting rod; a collar fixed to one end of the connecting rod and sleeved on the outer peripheral surface of the connecting pipe; and a clamping member fixed to the other end of the connecting rod, with a notch provided thereon for inserting into the port of the container. Thus, the connection stability between the connecting pipe and the container is improved. Since the connecting pipe and the container have only a single fixed fulcrum, if the staff accidentally touches it, the connection part between the connecting pipe and the container is extremely vulnerable to excessive force and damage. The setting of the fixator limits the top of the connecting pipe, reduces the pressure at the bottom connection of the connecting pipe, and improves the stability of the connecting pipe during operation.

[0012] In some embodiments, an anti-collision rubber ring is sleeved on the bottom of the container. Thus, the rubber ring protects the bottom of the container and makes the container more stable when placed.

[0013] A method of using a device for measuring the connected porosity of asphalt mixture specimens includes:

[0014] Step 1: Measure the dimensions. Place the specimen on a horizontal plane, and use a vernier caliper to measure the height values at four positions of the asphalt mixture specimen respectively, and take the average value h; then measure the diameter d of the asphalt mixture specimen.

[0015] Step 2: Calculate the volume of the specimen in air. Calculate the volume V of the specimen in air through the formula

[0016] Step 3: Record the initial height h1 of normal temperature water. Pour enough normal temperature water into the container (to ensure that when the specimen is placed in the container, the liquid will not overflow from the container port). After the liquid surface is stationary, record the liquid level height h1 at this time through the connecting pipe.

[0017] Step 4: Place the specimen. Slowly place the specimen into the container and make the specimen completely immersed in the liquid.

[0018] Step 5: Let it stand. Record the liquid level height h2. When the specimen is completely immersed in the liquid level, let it stand for at least 1 minute. After the liquid surface is completely stationary, read the liquid surface height h2 at this time through the connecting pipe.

[0019] Step 6: Calculate the volume of water displaced by the specimen. Through the formula

[0020] where D is the inner diameter of the container and D1 is the inner diameter of the connecting pipe.

[0021] ​Step 7: Calculate the connected porosity through the formula The connected porosity is calculated.

[0022] In summary, the present application includes at least the following summarized beneficial technical effects:

[0023] 1. The structure is simple and easy to operate. The main body of the device is composed of only two independent components, namely a container and a connecting pipe. Compared with the original measuring device, the hanging basket balance, the structure is greatly simplified, which is not only convenient for assembly and disassembly, but also convenient for transportation.

[0024] 2. It is convenient for maintenance. Since the connecting pipe and the container are detachably and fixedly connected, if the connecting pipe is damaged, it is convenient for the staff to immediately replace the connecting pipe.

[0025] 3. High precision. Both the container and the connecting pipe of this device are made of transparent materials, which is convenient for comparison and reduces experimental errors. Moreover, the diameter of the connecting pipe is controlled between 3 mm and 10 mm to avoid the generation of capillary phenomena, and the scale precision on the connecting pipe is above 0.5 mm, ensuring the measurement precision.

[0026] It should be understood that the content described in the section of the invention content is not intended to limit the key or important features of the embodiments of the present disclosure, nor to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 Shows the overall structural schematic diagram of Embodiment 1 of the present invention;

[0028] Figure 2 Shows the overall structural schematic diagram of Embodiment 2 of the present invention;

[0029] Figure 3 Shows the structural schematic diagram of the fixer in Embodiment 2 of the present invention;

[0030] Figure 4 Shows the structural schematic diagram of the anti-collision rubber ring in Embodiment 2 of the present invention;

[0031] Figure 5 Shows the flowchart of the method for using the device for measuring the connected porosity of asphalt mixture specimens of the present invention.

[0032] SYMBOL DESCRIPTION

[0033] 1. Container; 3. Water stop valve; 2. Connecting pipe; 4. Fixer; 41. Connecting rod; 42. Collar; 43. Clamping member; 5. Anti-collision rubber ring. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] Next, the preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0035] Example 1:

[0036] As Figure 1 shown, an apparatus for measuring the connected void ratio of asphalt mixture specimens according to an embodiment of the first aspect of the present invention includes a container 1, a water stop valve 3, and a connecting pipe 2.

[0037] The container 1 is a cylindrical glassware with an open upper end, facilitating water addition or pouring. Scale lines are provided on the outer peripheral surface of the container 1 at intervals along the height direction of the container 1, enabling the staff to generally understand the volume of the received normal temperature water.

[0038] A water stop valve 3 is provided at the bottom of the outer peripheral surface of the container 1. One end of the water stop valve 3 is fixedly connected to the container 1 and is in communication therewith. The other end of the water stop valve 3 is provided with a reduced opening, facilitating fixation with the connecting pipe 2. Since the connecting pipe 2 and the water stop valve 3 are fixedly inserted into each other, when the whole device is not in use, the connecting pipe 2 can be detached from the container 1, thereby reducing the overall volume occupation of the device, facilitating the staff to transport the device, and also facilitating the replacement of the damaged connecting pipe 2 if the connecting pipe 2 is damaged, improving the operation convenience.

[0039] The connecting pipe 2 is arranged on one side of the container 1, and its axis is parallel to the axis of the container 1. The lower end of the connecting pipe 2 is bent to one side and is inserted into the water outlet end of the water stop valve 3. The upper end surface of the connecting pipe 2 can be flush with the port of the container 1 or can be arranged higher than the port of the container 1. In this embodiment, the upper end surface of the connecting pipe 2 is flush with the upper port of the container 1, thereby facilitating the staff to confirm the tightness of the insertion of the connecting pipe 2 and the water stop valve 3. In this embodiment, the connecting pipe 2 is a glass transparent tube body, and scale lines with an accuracy of more than 0.5 mm are provided on its outer peripheral surface at intervals along its length direction, thereby facilitating the staff to take accurate readings. To improve the accuracy of reading the connecting pipe 2, the connecting pipe 2 is set as a tube body with a diameter of 3 mm - 10 mm. In this embodiment, 5 mm is taken as an example. Since the wall of the connecting pipe 2 is relatively thin, compared with the container 1, the influence of light refraction on reading is reduced. If the diameter of the connecting pipe 2 is less than 3 mm, capillary phase is likely to occur in the connecting pipe 2, thus affecting the accuracy of reading.

[0040] Example 2:

[0041] The difference from Example 1 is that, as Figure 2 and Figure 3As shown in the figure, in order to improve the stability of the device for measuring the connected void ratio of asphalt mixture specimens, a fixture 4 for assisting in fixing a pair of connecting pipes 2 is also provided at the bottle mouth of the container 1. The fixture 4 includes a connecting rod 41, one end of which is fixedly connected with a collar 42. The inner wall diameter of the collar 42 is equal to the outer wall diameter of the connecting pipe 2. Thus, after the collar 42 is sleeved on the outer peripheral surface of the connecting pipe 2, it plays a limiting role on the upper end of the connecting pipe 2. The other end of the connecting rod 41 is fixedly connected with a clamping member 43, and a notch is provided on the clamping member 43, which is convenient for inserting and connecting with the port of the container 1, thereby playing a fixing role on the connecting rod 41. After the staff fixes the connecting pipe 2 and the container 1 to each other, and then inserts and fixes the fixture 4 with the port of the container 1, the stability of the fixation of the connecting pipe 2 and the container 1 is improved.

[0042] As Figure 4 shown, since the device for measuring the connected porosity of asphalt mixture specimens is often used at the construction site, the container 1 is made of glass material, and dust and material particles on the outer diameter are extremely likely to damage the container 1. Therefore, an annular anti-collision rubber ring 5 is sleeved at the bottom of the container 1. The anti-collision rubber ring 5 includes an annular support bottom 51 and an anti-collision ring 52 integrally formed with the support bottom 51 and located on the circumferential surface of the bottom of the container 1. When the anti-collision rubber ring 5 is sleeved at the bottom of the container 1, it can avoid the collision of some sharp impurities at the bottom of the container 1 on the bottom of the container 1. The anti-collision ring on the circumferential side not only facilitates manual handling but also reduces the impact collision with the surrounding environment, thereby further improving the safety of using the container 1.

[0043] A method of using a device for measuring the connected porosity of asphalt mixture specimens, as Figure 5 shown, includes:

[0044] Step 1: Measure the dimensions. Place the specimen on a horizontal plane, and use a vernier caliper to measure the height values at four mutually perpendicular positions of the asphalt mixture specimen respectively, and take the average value h; then measure the diameter d of the asphalt mixture specimen.

[0045] Step 2: Calculate the volume of the specimen in the air. Calculate the volume V of the specimen in the air through the formula

[0046] Step 3: Record the initial height h1 of the normal temperature water. Pour enough normal temperature water into the container (to ensure that when the specimen is placed in the container, the liquid will not overflow from the container port). After the liquid level is stationary, record the liquid level height h1 at this time through the connecting pipe.

[0047] Step 4: Place the specimen. Slowly place the specimen into the container. Since the density of the specimen is about 2.3 g / cm 3 , the specimen is completely immersed in the liquid.

[0048] ​Step 5: Let it stand still and record the liquid level height h2. After the specimen is completely immersed in the liquid level, let it stand still for at least 1 minute. After the liquid surface is completely stationary, read the liquid surface height h2 at this time through the connecting pipe.

[0049] Step 6: Calculate the volume of water displaced by the specimen. Through the formula

[0050] where D is the inner diameter of the container and D1 is the inner diameter of the connecting pipe. D is the inner diameter of the container and D1 is the inner diameter of the connecting pipe.

[0051] Step 7: Calculate the connected porosity through the formula Calculate the connected porosity.

[0052] In the description of this specification, terms such as "connection", "installation", "fixation", etc. should all be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] The above are only the preferred embodiments of this application and are not used to limit this application. For those skilled in the art, this application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. An apparatus for measuring the connected porosity of asphalt mixture specimens, characterized in that, Comprising: A container, which is cylindrical, open at its upper end, for placing normal temperature water and fully placing the test specimen; A connecting pipe, which is a pipe body made of a transparent material, is located on one side of the container and the axis of the connecting pipe is parallel to the axis of the container. Both ends of the connecting pipe are open. One end of the connecting pipe is connected to the bottom of the peripheral surface of the container, and the other end is flush with or higher than the end surface of the container. Scale lines are marked along the length direction of the connecting pipe.

2. The device for measuring the connected porosity of asphalt mixture specimens according to claim 1, wherein: A water stop valve is further provided at the connection between the container and the connecting pipe.

3. The device for measuring the connected porosity of asphalt mixture specimens according to claim 2, characterized in that: The water stop valve is fixedly connected to the bottom of the peripheral surface of the container, and the bottom end of the connecting pipe is detachably and fixedly connected to the port of the water stop valve.

4. A device for measuring the connected porosity of asphalt mixture specimens according to claim 1, characterized in that: The diameter of the connecting pipe is set to be a pipe body greater than or equal to 3 mm and less than or equal to 10 mm.

5. A device for measuring the connected porosity of asphalt mixture specimens according to claim 1, characterized in that, The scale accuracy of the connecting pipe is a pipe body greater than 0.5 mm.

6. The device for measuring the connected porosity of asphalt mixture specimens according to claim 1, wherein The container is a cylindrical vessel made of a transparent material.

7. A device for measuring the connected porosity of asphalt mixture specimens according to claim 1, characterized in that, A fixator for assisting in fixing the connecting pipe is installed at the port of the container. The fixator includes A connecting rod; A collar, which is fixed to one end of the connecting rod and sleeved on the outer peripheral surface of the connecting pipe; A clamping member, which is fixed to the other end of the connecting rod, and a notch for inserting into the container port is provided thereon.

8. A device for measuring the connected porosity of asphalt mixture specimens according to claim 1, characterized in that, An anti-collision rubber ring is sleeved on the bottom of the container.

9. A method of using a device for measuring the connected porosity of asphalt mixture specimens, characterized in that, Comprising: Step 1: Measure the dimensions. Place the test specimen on a horizontal plane. Use a vernier caliper to measure the height values at four mutually perpendicular positions of the asphalt mixture test specimen respectively, and take the average value h. Then measure the diameter d of the asphalt mixture test specimen; Step 2: Calculate the volume of the test piece in air using the formula to calculate the volume V of the test piece in air; Step 3: Record the initial height h1 of the normal temperature water. Pour enough normal temperature water into the container (to ensure that when the test specimen is placed in the container, the liquid will not overflow from the container port). After the liquid level is stationary, record the liquid level height h1 at this time through the connecting pipe; Step 4: Place the test specimen. Slowly place the test specimen into the container and make the test specimen completely immersed in the liquid; Step 5: Let it stand. Record the liquid level height h2. When the test specimen is completely immersed in the liquid level, let it stand for at least 1 minute. After the liquid surface is completely stationary, read the liquid surface height h2 at this time through the connecting pipe; Step 6: Calculate the volume of water displaced by the test specimen. Through the formula: Where D is the inner diameter of the container and D1 is the inner diameter of the connecting pipe. Step 7: Calculate the connected porosity through the formula to calculate the connected porosity.

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