Rapid detection method for silt content of coarse aggregate

Abstract

The embodiment of the invention provides a method for rapidly detecting the silt content of coarse aggregate, and belongs to the technical field of constructional engineering, the method comprises the following steps: filling a volumetric flask with water, and calculating the total volume of the volumetric flask based on the mass and density of the water; the method comprises the following steps: adding an uncleaned coarse aggregate mud-containing sample into a volumetric flask, adding water until the volumetric flask is full, and weighing the total mass of an uncleaned mixture; calculating the mass of the uncleaned mud-containing sample based on the total mass of the uncleaned mixture and the total volume of the volumetric flask; cleaning and filtering the uncleaned mixture to obtain a mixture of the cleaned coarse aggregate containing no mud sample and water, and weighing the total mass of the cleaned mixture; based on the total mass of the cleaned mixture and the total volume of the volumetric flask, calculating the mass of the cleaned mud-free sample; and calculating the silt content of the coarse aggregate based on the mass of the uncleaned silt-containing sample and the mass of the cleaned silt-free sample. According to the scheme, the silt content detection time of the coarse aggregate can be greatly shortened, and the detection accuracy is improved.

Description

Technical Field

[0001] The invention relates to the technical field of construction engineering, and in particular to a rapid detection method and a detection tool for the mud content of coarse aggregate. Background Art

[0002] Coarse aggregate is often used in concrete and mortar, and its particle size is usually larger than 4.75 mm. According to standard classification, the common particle size range is from 5 mm to several tens of millimeters. The specific particle size requirements vary according to different engineering standards. For the detection of mud content of coarse aggregate in concrete mixing plants, the "water washing and drying method" in the current test procedures includes water washing, screening, drying, weighing and other links, which usually takes several hours or even a day to complete. The specific time depends on the amount of the sample, the condition of the equipment and the rate of water evaporation. This makes this method inefficient when test results need to be obtained quickly. And when the aggregate humidity is high or the weather is wet and cold, it will affect the accuracy of the results. Summary of the invention

[0003] In order to reduce the time for on-site detection of the mud content of coarse aggregate, this program proposes a rapid detection method for the mud content of coarse aggregate. The mud content of coarse aggregate is calculated by the mass change of the mixture of water and coarse aggregate. It does not require high-temperature drying, can greatly shorten the test time, is easy to implement on-site, and helps to adjust the selection of building materials in a timely manner.

[0004] According to a first aspect of the present invention, there is provided a method for rapid detection of mud content in coarse aggregate, comprising: filling a volumetric flask with water, and calculating the total volume of the volumetric flask based on the mass and density of the water; adding an uncleaned coarse aggregate mud-containing sample to the volumetric flask, adding water until the volumetric flask is full, and weighing the total mass of the uncleaned mixture; calculating the mass of the uncleaned mud-containing sample based on the total mass of the uncleaned mixture and the total volume of the volumetric flask; washing and filtering the uncleaned mixture to obtain a mixture of a washed coarse aggregate non-mud sample and water, and weighing the total mass of the washed mixture; calculating the mass of the washed non-mud sample based on the total mass of the washed mixture and the total volume of the volumetric flask; and calculating the mud content of coarse aggregate based on the mass of the uncleaned mud-containing sample and the mass of the washed non-mud sample.

[0005] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the mass m of the volumetric flask and the glass cover plate is weighed. p ; Weigh the mass of water when the volumetric flask is filled with water m w ; Calculate the total volume of the volumetric flask: V 总 =(m w -m p ) / ρ1, where ρ1 is the density of water.

[0006] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, an unwashed coarse aggregate mud sample is added to the volumetric flask; after adding a surfactant to the volumetric flask, the volumetric flask is filled with water, and the total mass of the unwashed mixture is weighed.

[0007] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the mass of the uncleaned mud-containing sample is calculated by the following formula: M1=m 2-2+ m 1-2= ρ 2* V 2-2+ (V 总- V 2-2 )ρ1 V 2-2= (M1-ρ 1* V 总 ) / (ρ2-ρ1) m 2-2= ρ 2* V 2-2 Where M1 is the total mass of the unwashed mixture that fills the volumetric flask, m 1-2 is the mass of water in the unwashed mixture that fills the volumetric flask, m 2-2 V is the mass of mud sample in the unwashed mixture that fills the volumetric flask, 总 is the total volume of the volumetric flask, V 2-2 is the volume of the mud sample in the unwashed mixture that fills the volumetric flask, ρ1 is the density of water, and ρ2 is the density of the sample.

[0008] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the mixture in the volumetric flask is stirred to separate the dust, silt and clay in the coarse aggregate mud sample from the sand particles to form a turbid liquid; the turbid liquid is poured onto a sieve to filter out particles with a particle size less than 0.075 mm, and the sieve hole diameter of the sieve is selected according to the aggregate particle size; after multiple water-adding, washing and filtering operations, the fine stone on the sieve is re-rinsed with water into the volumetric flask, water is added to fill the volumetric flask, and the total mass of the mixture after washing is weighed.

[0009] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the mass of the mud-free sample after cleaning is calculated by the following formula: M2=m 2-1+ m 1-1= ρ 2* V 2-1+ (V 总- V 2-1 )ρ1 V 2-1= (M2-ρ 1* V总 ) / (ρ2-ρ1) m 2-1= ρ 2* V 2-1 Where M2 is the total mass of the cleaned mixture that fills the volumetric flask, m 1-1 is the mass of water in the mixture after cleaning, m 2-1 V is the mass of the dry sample of coarse aggregate without mud in the washed mixture, 总 is the total volume of the volumetric flask, V 2-1 is the volume of the sample in the mixture of the cleaned mud-free sample and water, ρ1 is the density of water, and ρ2 is the density of the sample.

[0010] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the mud content of coarse aggregate is calculated by the following formula: Q n =(m 2-2 -m 2-1 ) / m 2-1 ; In the formula, Q n is the mud content of coarse aggregate, m 2-1 is the mass of dry sample of coarse aggregate without mud, m 2-2 It is the mass of dry sample of coarse aggregate containing mud.

[0011] Optionally, in the rapid detection method for the mud content of coarse aggregate provided by the present invention, the density of the water is the density value corresponding to the water temperature in the test specification during the test, and the temperature change of the water before and after the test does not exceed 2°C.

[0012] Optionally, in the rapid detection method for mud content of coarse aggregate provided by the present invention, the particle size of the coarse aggregate is 4.75 mm-37.5 mm.

[0013] According to the second aspect of the present invention, there is provided a tool for detecting the mud content of coarse aggregate, comprising: an electronic balance, a volumetric flask, and a set of sieves; the weighing capacity of the electronic balance is not less than 5000g, and the accuracy is at least 0.01g; the capacity of the volumetric flask is 1000mL; the set of sieves comprises a plurality of sieves with different apertures, and the minimum sieve aperture diameter is 0.075mm, which is used to filter out particles with a particle size less than 0.075mm in a coarse aggregate mud-containing sample; the detection tool is used to implement the rapid detection method for the mud content of coarse aggregate as described in the first aspect of the present invention.

[0014] The rapid detection method for the mud content of coarse aggregate provided by the present invention can at least achieve the following beneficial effects: 1. By using a volumetric flask to calculate the mud content, the complicated screening and drying steps in the traditional method are eliminated. Compared with the traditional water washing and drying method, the entire detection process does not require a long drying process, and the results can be obtained in a shorter time, avoiding errors caused by uneven temperature or insufficient drying time.

[0015] 2. The calculation of mud content is not affected by the initial humidity of aggregates and can maintain high stability under different environmental conditions (such as humid or dry climate). Compared with some special equipment or methods, this method is more flexible. It can be tested on site, especially suitable for places such as concrete mixing plants that require rapid feedback on mud content.

[0016] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present invention. Moreover, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 A schematic flow chart of a method 100 for rapidly detecting mud content in coarse aggregate according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0018] The mud content test of coarse aggregate for cement concrete is to determine the total content of silt and clay less than 0.075mm in crushed stone. In order to shorten the detection time, realize on-site feeding and inspection at any time during production, and ensure the timeliness of material collection, the embodiment of the present disclosure provides a rapid detection method for the mud content of coarse aggregate, which can quickly and accurately detect the mud content in coarse aggregate without waiting for drying.

[0019] The exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0020] If the densities of water and coarse aggregate are known, and the mass of the mixture and the total volume of the mixture are known and remain unchanged, the dry mass of the coarse aggregate without mud and the coarse aggregate with mud can be calculated respectively.

[0021] For example, if the density of the test water is ρ1 and the density of the coarse aggregate is ρ2, the total volume of the mixture when filling the volumetric flask is V. 总 , by weighing the total mass M of the mixture, the mass m2 of the coarse aggregate dry sample can be calculated: V 总 =m1 / ρ1+m2 / ρ2 M=m1+m2 Where m1 is the mass of water in the mixture that fills the volumetric flask, m2 is the mass of the coarse aggregate sample in the mixture that fills the volumetric flask, ρ1, ρ2, V 总 , M are known quantities.

[0022] This scheme ensures that the total volume of the mixture remains unchanged, changes the mass of the mixture, and obtains the dry sample mass of coarse aggregate without mud and coarse aggregate with mud respectively. Figure 1 FIG. 1 is a schematic flow chart of a method 100 for rapidly detecting mud content in coarse aggregate according to an embodiment of the present invention. Figure 1 As shown, in step S110, the volumetric flask is filled with water, and the total volume of the volumetric flask is calculated based on the mass and density of the water.

[0023] For example, select a volumetric flask and a glass cover, and weigh the mass of the volumetric flask and the glass cover as m. p , fill the volumetric flask with water and weigh the mass of water when it is full w The purpose of this step is to calculate the total volume V of the volumetric flask by measuring the mass of water. 总 : V 总 =(m w -m p ) / ρ1 Among them, according to the method specified in the aggregate test specification, the apparent density ρ2 of the sample to be tested and the temperature of the water are measured, and the density of water ρ1 is obtained by looking up the table in the specification. The temperature change of water before and after the test does not exceed 2°C.

[0024] Then in step S120, the unwashed coarse aggregate mud sample is added into the volumetric flask, water is added until the volumetric flask is full, and the total mass of the unwashed mixture is weighed.

[0025] Add an appropriate amount of unwashed coarse aggregate mud sample into the volumetric flask, retain some water in the volumetric flask, add the surfactant into the volumetric flask, rotate the volumetric flask to expel the air, fill the volumetric flask with water, and weigh the total mass M1 of the unwashed mixture containing the mud sample and water, also accurate to 0.01g.

[0026] In step S130, the mass of the uncleaned muddy sample is calculated based on the total mass of the uncleaned mixture and the total volume of the volumetric flask.

[0027] The mass of the uncleaned muddy sample can be calculated by the following formula: M1=m 2-2+ m 1-2= ρ 2* V 2-2+ (V 总- V 2-2 )ρ1; V 2-2= (M1-ρ 1* V 总 ) / (ρ2-ρ1); m 2-2= ρ 2* V 2-2 ; Where M1 is the total mass of the unwashed mixture that fills the volumetric flask, m 1-2 is the mass of water in the unwashed mixture that fills the volumetric flask, m 2-2 V is the mass of mud sample in the unwashed mixture that fills the volumetric flask, 总 is the total volume of the volumetric flask, V 2-2 is the volume of the mud sample in the unwashed mixture that fills the volumetric flask, ρ1 is the density of water, and ρ2 is the density of the sample.

[0028] In step S140, the unwashed mixture is washed and filtered to obtain a washed coarse aggregate mixture without mud sample and water, and the total mass of the washed mixture is weighed.

[0029] The mixture in the volumetric flask is stirred to separate the dust, silt and clay in the coarse aggregate mud sample from the sand particles to form a turbid liquid. The turbid liquid is slowly poured into a set sieve with a minimum aperture of 0.075 mm to filter out particles smaller than 0.075 mm. The above cleaning and filtering steps are repeated until the sieve is clean. The fine stones on the sieve are rinsed with water into the volumetric flask again, and the volumetric flask is filled with water. The total mass M2 of the mixture after cleaning is weighed.

[0030] It should be noted that the sieve can be selected according to the aggregate particle size of 4.75mm, 0.075mm, or 2.36mm, 0.075mm. Both sides of the sieve should be moistened with water before the test to avoid stone loss during the entire test process.

[0031] In step S150, the mass of the cleaned sample without mud is calculated based on the total mass of the cleaned mixture and the total volume of the volumetric flask.

[0032] In one embodiment of the present disclosure, the mass of the cleaned sample without mud is calculated by the following formula: M2=m 2-1+ m 1-1= ρ 2* V 2-1+ (V 总- V 2-1 )ρ1; V 2-1= (M2-ρ 1* V 总 ) / (ρ2-ρ1); m 2-1= ρ 2* V 2-1 ; Where M2 is the total mass of the cleaned mixture that fills the volumetric flask, m 1-1 is the mass of water in the mixture after cleaning, m 2-1 V is the mass of the dry sample of coarse aggregate without mud in the washed mixture, 总 is the total volume of the volumetric flask, V 2-1 is the volume of the sample in the mixture of the cleaned mud-free sample and water, ρ1 is the density of water, and ρ2 is the density of the sample.

[0033] Finally, in step S160, the mud content of the coarse aggregate is calculated based on the mass of the uncleaned mud-containing sample and the mass of the cleaned mud-free sample.

[0034] Calculate the mass m of the dry sample of coarse aggregate without mud after cleaning 2-1 and dry sample mass of muddy coarse aggregate m 2-2 Afterwards, the mud content of the sample is quickly calculated using the following formula: Q n =(m 2-2 -m 2-1 ) / m 2-1 ; Among them, Q n is the mud content of coarse aggregate, m 2-1 is the mass of dry sample of coarse aggregate without mud, m 2-2 It is the mass of dry sample of coarse aggregate containing mud.

[0035] It should be noted that M1 and M2 used in the formula are the mass m minus the volumetric flask and glass cover. p After the net content.

[0036] In order to quickly measure the mud content in coarse aggregate with a particle size of 4.75-37.5 mm in the natural state, that is, to determine the proportion of soil (such as dust, silt, clay) in the coarse aggregate, this scheme calculates the mass of the soil by comparing the mass change of the mud-containing sample and the sample after removing the soil, thereby obtaining the mud content of the coarse aggregate. The detection tools used in the embodiment of the present disclosure include: an electronic balance, a volumetric flask, and a set of sieves. The weighing of the electronic balance is not less than 5000g, and the accuracy is at least 0.01g; the volume of the volumetric flask is 1000mL; the set of sieves includes a plurality of sieves with different apertures, and the minimum sieve hole diameter is 0.075mm, which is used to filter out particles with a particle size less than 0.075mm in the mud-containing sample of the coarse aggregate.

[0037] After field tests, this scheme has shortened the mud content test time from 24 hours in the current standard to 15 to 30 minutes, achieving the purpose of inspecting coarse aggregate at any time when it arrives on site, and improving the detection efficiency by more than 95%. The method is simpler and more convenient than the method in the current standard, and is conducive to on-site operation.

[0038] In summary, the rapid detection method for the mud content of coarse aggregate provided by the present invention can at least achieve the following beneficial effects: 1. By using a volumetric flask to calculate the mud content, the complicated screening and drying steps in the traditional method are eliminated. Compared with the traditional water washing and drying method, the entire detection process does not require a long drying process, and the results can be obtained in a shorter time, avoiding errors caused by uneven temperature or insufficient drying time.

[0039] 2. The calculation of mud content is not affected by the initial humidity of aggregates and can maintain high stability under different environmental conditions (such as humid or dry climate). Compared with some special equipment or methods, this method is more flexible. It can be tested on site, especially suitable for places such as concrete mixing plants that require rapid feedback on mud content.

[0040] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0041] Similarly, it should be understood that in order to streamline the present disclosure and aid in understanding one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, this disclosed method should not be interpreted as reflecting the following intention: that the claimed invention requires more features than the features explicitly recited in each claim. More specifically, as reflected in the claims below, inventive aspects lie in less than all the features of the individual embodiments disclosed above. Therefore, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, with each claim itself serving as a separate embodiment of the present invention.

[0042] Those skilled in the art will appreciate that the modules or units or components of the devices in the examples disclosed herein may be arranged in the devices described in the embodiment, or alternatively may be located in one or more devices different from the devices in the examples. The modules in the foregoing examples may be combined into one module or may be divided into multiple submodules.

[0043] Although the present invention has been described according to a limited number of embodiments, it will be apparent to those skilled in the art, with the benefit of the above description, that other embodiments may be envisioned within the scope of the invention thus described. In addition, it should be noted that the language used in this specification is selected primarily for readability and teaching purposes, rather than for explaining or defining the subject matter of the present invention. Therefore, many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the appended claims. The disclosure of the present invention is illustrative and not restrictive with respect to the scope of the present invention, and the scope of the present invention is defined by the appended claims.

Claims

1. A rapid detection method for the mud content of coarse aggregate, characterized in that: include: Fill the volumetric flask with water and calculate the total volume of the flask based on the mass and density of the water; Add the unwashed coarse aggregate mud sample into the volumetric flask, add water until the volumetric flask is full, and weigh the total mass of the unwashed mixture; Calculate the mass of the uncleaned muddy sample based on the total mass of the uncleaned mixture and the total volume of the volumetric flask; The unwashed mixture is washed and filtered to obtain a washed coarse aggregate mixture without mud sample and water, and the total mass of the washed mixture is weighed; Based on the total mass of the mixture after cleaning and the total volume of the volumetric flask, the mass of the cleaned sample without mud is calculated; as well as The mud content of the coarse aggregate is calculated based on the mass of the uncleaned mud-containing sample and the mass of the cleaned mud-free sample.

2. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The step of filling the volumetric flask with water and calculating the total volume of the volumetric flask based on the mass and density of the water comprises: Weigh the mass m of the volumetric flask and glass cover p ; Weigh the mass of water when the volumetric flask is filled with water m w ; Calculate the total volume of the volumetric flask: V 总 =(m w -m p ) / ρ1, where ρ1 is the density of water.

3. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The steps of adding the unwashed coarse aggregate mud sample into the volumetric flask, adding water until the volumetric flask is full, and weighing the total mass of the unwashed mixture include: Adding the unwashed coarse aggregate mud sample into the volumetric flask; After adding the surfactant to the volumetric flask, fill the volumetric flask with water and weigh the total mass of the unwashed mixture.

4. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The mass of the uncleaned muddy sample is calculated by the following formula: M1=m 2-2+ m 1-2= ρ 2* V 2-2+ (V 总- V 2-2 )ρ1; V 2-2= (M1-p) 1* V 总 ) / (ρ2-ρ1); m 2-2= r 2* V 2-2 ; Where M1 is the total mass of the unwashed mixture that fills the volumetric flask, m 1-2 is the mass of water in the unwashed mixture that fills the volumetric flask, m 2-2 V is the mass of mud sample in the unwashed mixture that fills the volumetric flask, 总 is the total volume of the volumetric flask, V 2-2 is the volume of the mud sample in the unwashed mixture that fills the volumetric flask, ρ1 is the density of water, and ρ2 is the density of the sample.

5. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The step of washing and filtering the unwashed mixture to obtain a washed coarse aggregate mixture without mud sample and water, and weighing the total mass of the washed mixture comprises: The mixture in the volumetric flask is stirred to separate the dust, silt and clay in the coarse aggregate mud sample from the sand particles to form a turbid liquid; Pour the turbid liquid onto a sieve set to filter out particles with a particle size less than 0.075 mm, wherein the sieve hole diameter of the sieve set is selected according to the aggregate particle size; After multiple water-adding, cleaning and filtering operations, the fine stones on the screen are rinsed again into the volumetric flask with water, and the volumetric flask is filled with water. The total mass of the mixture after cleaning is weighed.

6. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The mass of the cleaned sample without mud is calculated by the following formula: M2=m 2-1+ m 1-1= ρ 2* In 2-1+ (In) 总- In 2-1 )ρ1; V 2-1= (M2-p) 1* V 总 ) / (ρ2-ρ1); m 2-1= r 2* V 2-1 ; Where M2 is the total mass of the cleaned mixture that fills the volumetric flask, m 1-1 is the mass of water in the mixture after cleaning, m 2-1 V is the mass of the dry sample of coarse aggregate without mud in the washed mixture, 总 is the total volume of the volumetric flask, V 2-1 is the volume of the sample in the mixture of the cleaned mud-free sample and water, ρ1 is the density of water, and ρ2 is the density of the sample.

7. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The mud content of coarse aggregate is calculated by the following formula: Q n =(m 2-2 -m 2-1 ) / m 2-1 ; In the formula, Q n is the mud content of coarse aggregate, m 2-1 is the mass of dry sample of coarse aggregate without mud, m 2-2 It is the mass of dry sample of coarse aggregate containing mud.

8. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The density of water is the density value corresponding to the water temperature in the test specification during the test, and the temperature change of water before and after the test does not exceed 2°C.

9. The rapid detection method for mud content in coarse aggregate according to claim 1, characterized in that: The particle size of the coarse aggregate is 4.75mm-37.5mm.

10. A tool for detecting mud content in coarse aggregate, characterized in that: include: Electronic balance, volumetric flask, set of sieves; the weighing capacity of the electronic balance is not less than 5000g, and the accuracy is at least 0.01g; the capacity of the volumetric flask is 1000mL; the set of sieves includes a plurality of sieves with different apertures, and the minimum sieve aperture diameter is 0.075mm, which is used to filter out particles with a particle size less than 0.075mm in the coarse aggregate mud-containing sample; the detection tool is used to implement the rapid detection method of the mud content of coarse aggregate as described in any one of claims 1-9.

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