A method and device for measuring moisture content of fine aggregate

Abstract

The present invention relates to the technical field of concrete production, and in particular to a method and device for measuring the moisture content of fine aggregate. The method comprises the following steps: weighing a set mass of fine aggregate and pouring it into a sand bottle, and pouring water into the sand bottle to submerge the fine aggregate to a first set height; shaking the sand bottle to remove bubbles between the fine aggregate particles until no bubbles are generated during the shaking of the sand bottle; continuing to add water to the sand bottle until the water is added to the second set height of the sand bottle and then weighing to obtain a first total mass; and calculating the moisture content of the fine aggregate based on the set mass and the first total mass. The present invention can solve the problem of low efficiency of the method and device for measuring the moisture content of fine aggregate in the prior art.

Description

Technical Field

[0001] The invention relates to the technical field of concrete production, and in particular to a method and a device for measuring the moisture content of fine aggregate. Background Art

[0002] Fine aggregate is a raw material used to produce concrete. Fine aggregate stored in silos is often moist and has a certain moisture content. Because fine aggregate has moisture content, before producing concrete, its moisture content must be measured to accurately determine the amount of fine aggregate to ensure that the performance of the concrete meets the construction requirements.

[0003] There are two main methods for determining the moisture content of fine aggregate, namely the drying method and the alcohol combustion method. The moisture content of fine aggregate is determined by drying the fine aggregate in an oven. It usually takes 3-6 hours to completely dry the fine aggregate, depending on the moisture content, which is very time-consuming. Alcohol burns faster. In order to make the fine aggregate lose water quickly and completely, the fine aggregate needs to be burned with alcohol several times. After a cycle of burning, cooling, burning, and cooling again, the fine aggregate can be completely dried. This process also takes nearly an hour. In addition, there are certain safety hazards in the storage and use of alcohol.

[0004] In summary, the existing methods for determining the moisture content of fine aggregate have the problems of complicated steps, wasting time and low work efficiency. Summary of the invention

[0005] In view of the defects existing in the prior art, the object of the present invention is to provide a method and device for measuring the moisture content of fine aggregate, which can solve the problem of low efficiency of the method and device for measuring the moisture content of fine aggregate in the prior art.

[0006] In order to achieve the above purpose, the technical solution adopted by the present invention is:

[0007] In one aspect, the present invention provides a method for determining the moisture content of fine aggregate, comprising the following steps:

[0008] Weigh a set mass of fine aggregate and pour it into a sand container, and pour water into the sand container to submerge the fine aggregate to a first set height;

[0009] Shake the sand bottle to remove the bubbles between the fine aggregate particles until no bubbles are generated during the shaking of the sand bottle;

[0010] Continue to add water to the sand container until the water reaches the second set height of the sand container, then weigh it to obtain a first total mass;

[0011] The moisture content of the fine aggregate is calculated based on the set mass and the first total mass.

[0012] In some optional embodiments, the step of calculating the moisture content of the fine aggregate according to the set mass and the first total mass comprises the following steps:

[0013] According to the formula The drainage volume ΔV of the fine aggregate is calculated, where m is the second total mass of the sand container filled with water to the second set height, m ​​is the first total mass, m is the set mass of the fine aggregate sample, and ρ w is the density of water;

[0014] According to the formula The moisture content of fine aggregate is calculated, where ρ s is the apparent density of fine aggregate.

[0015] In some optional embodiments, when the air temperature is less than the air temperature during calibration within the set range, the second total mass m of the sand container filled with water to the second set height adopts the calibration value;

[0016] When the air temperature is not less than the set range with the air temperature during calibration, water is added to the sand container to the second set height and then weighed as the second total mass m.

[0017] In some optional embodiments, the outer wall of the sand container is wiped dry before weighing the sand container.

[0018] In some optional embodiments, the sand container used includes a feed pipe, and the feed pipe is provided with a drainage tube, and the height from adding water from the feed pipe to the height at which water is dispensed from the drainage tube is used as the second set height.

[0019] In another aspect, the present invention provides a device for measuring the moisture content of fine aggregate, comprising:

[0020] Sand bottle;

[0021] A feed pipe, which is arranged above the sand containing bottle and is in communication with the sand containing bottle;

[0022] A fine drainage tube is arranged on the feed tube in an upwardly inclined manner, the diameter of the fine drainage tube is smaller than the diameter of the feed tube, and the outlet of the fine drainage tube is located below the inlet of the fine drainage tube.

[0023] In some optional embodiments, a bottle stopper is further included, wherein the bottle stopper includes:

[0024] A plug body, which is used to be arranged in the sand container;

[0025] A plug handle is connected to the plug body and is used to deliver the plug body into the feed pipe below the drainage capillary and to take out the plug body.

[0026] In some optional embodiments, the drainage tube includes a connecting end and a vertical end that are interconnected, and the connecting end is connected to the feed pipe.

[0027] In some optional embodiments, the connecting end forms an angle of ° with the feeding pipe, and the vertical end is vertically upward.

[0028] In some optional embodiments, the inlet of the feed pipe is in a bell-mouth shape.

[0029] Compared with the prior art, the advantages of the present invention are: the method can quickly determine the moisture content of fine aggregate by using the volume estimation formula, and does not require drying the wet fine aggregate for several hours, nor does it involve unsafe operations, and can quickly determine the moisture content of fine aggregate. The operation is simple and safe, reducing the labor intensity of test personnel and eliminating the safety hazards of using alcohol. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0031] Figure 1 is a flow chart of a method for determining moisture content of fine aggregate in an embodiment of the present invention;

[0032] Figure 2 Schematic diagram of the structure of a device for measuring the moisture content of fine aggregate in an embodiment of the present invention.

[0033] In the figure: 1. sand container; 2. feed pipe; 3. drainage tube; 4. bottle stopper; 41. stopper body; 42. stopper handle. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0035] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0036] like Figure 1 As shown, the present invention provides a method for measuring the moisture content of fine aggregate, comprising the following steps:

[0037] S1: Weigh a set mass of fine aggregate and pour it into the sand container 1, and pour water into the sand container 1 to submerge the fine aggregate to a first set height.

[0038] In this embodiment, there is no order in the steps of weighing a set mass of fine aggregate and pouring it into the sand container 1 and pouring water into the sand container 1 to submerge the fine aggregate to the first set height. The order can be adjusted according to needs without affecting the test accuracy.

[0039] In this example, the set mass of the fine aggregate is about 300 g, and water is poured into the sand container 1 to submerge the fine aggregate until the first set height is about half of the sand container 1.

[0040] S2: Shake the sand bottle 1 to remove air bubbles between the fine aggregate particles until no air bubbles are generated during the shaking of the sand bottle 1.

[0041] In this embodiment, the sand container 1 is held by hand and shaken until no bubbles are generated, thereby determining that all particles of the fine aggregate are completely filled with water.

[0042] S3: Continue to add water to the sand container 1 until the water reaches the second set height of the sand container 1 and then weigh it to obtain a first total mass.

[0043] Preferably, the sand container 1 used comprises a feed pipe 2, and a drainage capillary 3 is provided on the feed pipe, and the height from adding water from the feed pipe 2 to the water being dispensed from the drainage capillary 3 is used as the second set height.

[0044] In this embodiment, the outer wall of the sand containing bottle 1 is wiped dry before the sand containing bottle 1 is weighed to obtain the first total mass.

[0045] In some optional embodiments, a second total mass is obtained when the sand bottle 1 is completely filled with water to a second set height.

[0046] In this embodiment, the step of obtaining the second total mass after the sand bottle 1 is completely filled with water to the second set height may be performed before step S1 or after step S3, which does not affect the test result.

[0047] In addition, in some optional embodiments, when the air temperature is less than the air temperature during calibration within a set range, the sand bottle 1 is filled with water to a second set height and the second total mass m2 adopts a calibrated value, that is, before testing, it has been calibrated through multiple sets of data.

[0048] When the air temperature is not less than the set range with the air temperature during calibration, water is added to the sand container 1 to reach the second set height and then weighed as the second total mass m2.

[0049] Preferably, the sand container 1 is wiped dry before weighing the sand container 1 to obtain the second total mass.

[0050] S4: Calculate the moisture content of the fine aggregate according to the set mass and the first total mass.

[0051] Preferably, the step of calculating the moisture content of the fine aggregate according to the set mass and the first total mass comprises the following steps:

[0052] According to the formula The drainage volume ΔV of the fine aggregate is calculated, where m2 is the second total mass of the sand container 1 filled with water to the second set height, m1 is the first total mass, m is the set mass of the fine aggregate sample, and ρ w is the density of water;

[0053] According to the formula The moisture content of fine aggregate is calculated, where ρ s is the apparent density of fine aggregate.

[0054] In summary, this method can quickly determine the moisture content of fine aggregate using the volume estimation formula. It does not require drying the wet fine aggregate for several hours, and there is no unsafe operation. It can quickly determine the moisture content of fine aggregate. It is simple and safe to operate, reduces the labor intensity of test personnel, and eliminates the safety hazards of using alcohol.

[0055] like Figure 2 As shown, on the other hand, the present invention also provides a device for measuring the moisture content of fine aggregate, including: a sand bottle 1; a feed pipe 2, which is arranged above the sand bottle 1 and is connected to the sand bottle 1; and a drainage capillary 3, which is arranged on the feed pipe 2 in an inclined manner, the diameter of the drainage capillary 3 is smaller than the diameter of the feed pipe 2, and the outlet of the drainage capillary 3 is located below the inlet of the drainage capillary 3.

[0056] In this embodiment, the device can be used to pour fine aggregate into the sand bottle 1 through the feed pipe 2. Since the feed thick pipe and the sand bottle 1 are relatively thick and have a large cross-section, due to the surface tension of water. It is difficult to accurately and quickly record the water added to the set height. Therefore, in order to accurately record the height of the water, the overflow height of the water is used as the set height. If the feed pipe 2 is directly used as a drain, the drainage error will be large, and the corresponding moisture content error will be large. In order to minimize the drainage error, the diameter of the drain port should be as small as possible. This is contradictory to the entry of fine aggregate samples. If the diameter of the drain port is too small, it is difficult for fine aggregate samples to enter. Setting a fine drainage pipe is an effective measure to resolve the above contradiction, which is conducive to improving the accuracy of the water addition height recording, and can also increase the recording speed and detection efficiency. In addition, it is also conducive to reasonably enlarging the feed pipe 2, so as to facilitate the smooth entry of moist fine aggregate into the sand bottle 1, thereby successfully completing the drainage operation. The device is light and simple, easy to carry, and suitable for both indoor and outdoor use.

[0057] Preferably, it also includes a bottle stopper 4, which includes: a stopper body 41, which is used to be set in the sand container 1; and a stopper handle 42, which is connected to the stopper body 41 and is used to send the stopper body 41 to the feed pipe 2 below the drainage tube 3, and the stopper body 41 can be taken out.

[0058] In this embodiment, the device also includes a bottle stopper 4, which includes: a stopper body 41, which is used to be set in the sand bottle 1; and a stopper handle 42, which is connected to the stopper body 41 and is used to send the stopper body 41 to the feed pipe 2 below the drainage tube 3, and the stopper body 41 can be taken out.

[0059] In this embodiment, the plug body 41 can be sent into the feed pipe 2 through the plug handle 42, and the plug body 41 can be placed below the connection between the plug body 41 and the drainage tube 3. When the sand bottle 1 is shaken, water or fine aggregate in the sand bottle 1 can be prevented from being shaken out of the sand bottle 1.

[0060] Preferably, a sealing ring is provided on the outside of the plug body 41. In this embodiment, a sealing ring is provided on the outside of the plug body 41 to obtain a better sealing effect.

[0061] Preferably, the drainage tube 3 includes a connecting end and a vertical end which are connected to each other, and the connecting end is connected to the feeding pipe 2 .

[0062] Preferably, the connecting end forms an angle of 30° with the feeding pipe 2, and the vertical end is vertically upward.

[0063] In this embodiment, the drainage capillary is made of glass or transparent plastic, and is composed of an oblique tube and a vertical tube with an inner diameter of 2 mm and a wall thickness of 2 mm. The oblique tube is 30° with the vertical tube, the length of the oblique tube is 20 mm, and the length of the vertical tube is 10 mm. The oblique tube plays the role of connecting the thick feed tube and the drainage capillary, and at the same time uses the inclination to prevent the fine aggregate from falling from the feed tube 2, and the fine aggregate particles from accidentally flowing out of the drainage capillary 3 during the process of shaking the sand bottle 1 to discharge bubbles, so as to avoid the loss of fine aggregate particles and affect the accuracy of the test. The vertical tube can discharge the part exceeding the tube end to maintain the volume of the entire instrument unchanged. The sand bottle 1 is made of glass or transparent plastic, with an inner diameter of 100 mm, a height of 51 mm, and a cylindrical structure with a wall thickness of 2 mm.

[0064] Preferably, the inlet of the feed pipe 2 is in a bell-mouth shape. In this embodiment, the inlet of the feed pipe 2 is in a bell-mouth shape, which is helpful for feeding fine aggregate into the sand container 1.

[0065] In this embodiment, the feed pipe 2 is made of glass or transparent plastic, and the upper structure is a funnel-shaped structure with an upper inner diameter of 45 mm, a lower inner diameter of 25 mm, a height of 10 mm, and a wall thickness of 2 mm, that is, a sand container 1; the lower structure is a hollow cylindrical structure with an inner diameter of 25 mm, a height of 50 mm, and a wall thickness of 2 mm. Through the feed thick pipe, fine aggregate and water can flow out and be discharged smoothly.

[0066] In the description of the present application, it should be noted that the terms "upper", "lower", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application 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 a limitation on the present application. 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 an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to the specific circumstances.

[0067] It should be noted that, in this application, relational terms such as "first" and "second" are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0068] The above description is only a specific implementation of the present application, so that those skilled in the art can understand or implement the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest range consistent with the principles and novel features applied for herein.

Claims

1. A method for determining the moisture content of fine aggregate, characterized in that: The following steps are involved: Weigh a set mass of fine aggregate and pour it into a sand container (1), and pour water into the sand container (1) to submerge the fine aggregate to a first set height; Shaking the sand container (1) to remove air bubbles between the fine aggregate particles until no air bubbles are generated during the shaking of the sand container (1); Continue to add water to the sand container (1) until the water reaches the second set height of the sand container (1), and then weigh it to obtain a first total mass; The sand container (1) used comprises a feed pipe (2), and a water discharge capillary (3) is provided on the feed pipe, and a height at which water flows out of the water discharge capillary (3) after water is added from the feed pipe (2) is used as a second set height; The fine drainage tube (3) is arranged on the feed tube (2) in an inclined manner, the diameter of the fine drainage tube (3) is smaller than the diameter of the feed tube (2), and the outlet of the fine drainage tube (3) is located below the inlet of the feed tube (2); It also includes a bottle stopper (4), wherein the bottle stopper (4) includes: A plug body (41) is used to be arranged in the sand container (1); a plug handle (42) connected to the plug body (41) and used to deliver the plug body (41) into the feed pipe (2) below the drainage capillary (3) and to remove the plug body (41); The moisture content of the fine aggregate is calculated based on the set mass and the first total mass.

2. A method for determining the moisture content of fine aggregate according to claim 1, characterized in that: The step of calculating the moisture content of the fine aggregate according to the set mass and the first total mass comprises the following steps: According to the formula Calculate the drainage volume of fine aggregate , wherein m2 is the second total mass of the sand container (1) when all water is added to the second set height, m1 is the first total mass, and m is the set mass of the fine aggregate sample. is the density of water; According to the formula The moisture content of fine aggregate is calculated, where is the apparent density of fine aggregate.

3. A method for measuring the moisture content of fine aggregate according to claim 2, characterized in that: When the air temperature is less than the air temperature during calibration within the set range, the sand container (1) is completely filled with water to a second set height and the second total mass m2 adopts the calibration value; When the air temperature is not less than the air temperature during calibration within the set range, water is added to the sand container (1) to a second set height and then weighed to obtain the second total mass m2.

4. A method for measuring moisture content of fine aggregate according to claim 1, characterized in that: Before weighing the sand container (1), wipe the outer wall of the sand container (1) dry.

5. A device for implementing the method for determining the moisture content of fine aggregate according to claim 1, characterized in that: include: Sand bottle (1); A feed pipe (2), which is arranged above the sand container (1) and is in communication with the sand container (1); a fine drainage tube (3) which is arranged on the feed tube (2) in an inclined manner, the diameter of the fine drainage tube (3) being smaller than the diameter of the feed tube (2), and the outlet of the fine drainage tube (3) being located below the inlet of the feed tube (2); A bottle stopper (4), wherein the bottle stopper (4) comprises: A plug body (41) is used to be arranged in the sand container (1); A plug handle (42) is connected to the plug body (41) and is used to deliver the plug body (41) into the feed pipe (2) below the drainage capillary (3) and to remove the plug body (41); the inlet of the feed pipe (2) is in the shape of a bell mouth.

6. A device for measuring moisture content of fine aggregate according to claim 5, characterized in that: The drainage capillary tube (3) comprises a connecting end and a vertical end which are connected to each other, and the connecting end is connected to the feed pipe (2).

7. A device for measuring moisture content of fine aggregate according to claim 6, characterized in that: The connecting end and the feed pipe (2) form an angle of 30°, and the vertical end points vertically upward.

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