Method for detecting cement dosage of cement stabilized macadam with ultra-large particle size

Abstract

The invention discloses a cement dosage detection method for oversized-particle-size cement stabilized macadam, which is characterized in that on one hand, the cement stabilized macadam passes through a 4.75 mm sieve to avoid coarse and fine segregation and poor representativeness of a sample, so that the aim of rapidly and accurately testing the cement dosage of the cement stabilized macadam is fulfilled, and on the other hand, an EDTA (Ethylene Diamine Tetraacetic Acid) titration method nomogram drawn by a temperature influence factor is considered; and the cement dosage of the cement stabilized macadam can be accurately judged.

Description

Technical Field

[0001] The invention belongs to the technical field of traffic civil engineering, and in particular relates to a cement dosage detection method for cement-stabilized crushed stone with super-large particle size. Background Art

[0002] The cement dosage of cement-stabilized gravel is an important indicator for quality control of construction sites. The key to quality control is that the test results accurately reflect actual production, and the representativeness of sampling (whether it is consistent with the designed mix ratio) directly affects the test results.

[0003] At present, the method for measuring cement dosage of cement-stabilized crushed stone mixture on the construction site is EDTA titration method, the principle of which is: firstly, 10% ammonium chloride solution is used to dissolve the Ca in cement-stabilized crushed stone. 2+ Then, a standard solution of disodium EDTA was used to remove Ca 2+ The consumption of disodium EDTA standard solution is proportional to the corresponding cement dosage (the size of cement dosage is proportional to Ca 2+ During the test, take about 1000g of cement-stabilized gravel mixture at room temperature, put it into 2000mL of 10% ammonium chloride solution and stir evenly, titrate it with disodium EDTA standard solution until the solution turns rose red, and record the amount of disodium EDTA standard solution consumed. Draw an EDTA standard curve between cement dosage and disodium EDTA standard solution consumption, and determine the cement dosage in cement-stabilized gravel according to the standard curve during construction.

[0004] The above EDTA titration method uses designed mix ratios and laboratory mixed materials as test objects. It is difficult to ensure the representativeness of samples when sampling on site or at a mixing station, especially for densely packed mixtures. If the sample has a high content of coarse aggregate, the cement dosage test value will be too small, otherwise the test value will be too large, which cannot reflect the true value of cement dosage.

[0005] In addition, the EDTA titration method currently used is carried out at room temperature and does not take into account the impact of ambient temperature on the test results. However, the Ca content of cement-stabilized crushed stone with the same material composition varies at different ambient temperatures. 2+ The amount will vary, so not considering the test environment temperature will lead to inconsistent test results. Summary of the invention

[0006] The purpose of the present invention is to provide a cement dosage detection method for ultra-large particle size cement stabilized crushed stone, so as to solve the problem that the EDTA titration method may lead to inaccurate test results due to the unrepresentative sampling and the test not considering the influence of ambient temperature.

[0007] In order to achieve the above object, the technical solution adopted by the present invention is: a cement dosage detection method for super-large particle size cement stabilized gravel, which is specifically implemented according to the following steps:

[0008] Step 1, mixing cement-stabilized gravel with different cement dosages according to the optimal moisture content of cement-stabilized gravel at different test temperatures;

[0009] Step 2, sieving the cement-stabilized gravel mixtures with different dosages;

[0010] Step 3, take the undersize mixture after sieving in step 2 and put it into an enamel cup, stir the lumps with a stirring rod, then add 10% ammonium chloride solution, and perform an EDTA titration test. After the solution turns rose red, record the EDTA solution consumption of the mixture solution with different cement dosages; wherein every 100g of undersize mixture corresponds to 200ml of 10% ammonium chloride solution;

[0011] Step 4, drawing an EDTA titration Fanograph according to the standard curve relationship between cement dosage and EDTA solution consumption at different test temperatures;

[0012] Step 5, when measuring the cement dosage of the cement-stabilized crushed stone mixture at the construction site, a representative sample is taken and sieved to obtain a cement mortar sample;

[0013] Step 6, take the cement mortar sample and put it into an enamel cup, use a stirring rod to break up the lumps, then add 10% ammonium chloride solution, perform EDTA titration test, and record the EDTA solution consumption after the solution turns rose red;

[0014] Step 7, according to the EDTA solution consumption of the cement mortar sample and the test environment temperature, the cement content of the cement-stabilized crushed stone actually measured in the on-site construction is obtained through the EDTA titration Fanomorph diagram.

[0015] As a preferred technical solution of the present invention, in step 1, the different test temperatures are 15°C, 20°C, 25°C, 30°C and 35°C.

[0016] As a preferred technical solution of the present invention, in step 1, the cement-stabilized crushed stone with different cement dosages are 0, 1%, 3% and 5% respectively.

[0017] As a preferred technical solution of the present invention, in step 2 and step 5, the slurry is sieved through a 4.75 mm sieve.

[0018] As a preferred technical solution of the present invention, in step 5, the product is sieved through a 4.75 mm sieve.

[0019] The beneficial effects of the present invention are as follows: (1) The cement dosage detection method of the present invention for cement-stabilized gravel with super-large particle size avoids sample coarse-fine segregation and poor representativeness by passing the cement-stabilized gravel through a 4.75 mm sieve, thereby achieving the goal of rapid and accurate cement dosage testing of cement-stabilized gravel. (2) The cement dosage detection method of the present invention for cement-stabilized gravel with super-large particle size considers the temperature influence factor to draw the EDTA titration Fanomorph diagram, which can prepare and judge the cement dosage of cement-stabilized gravel. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is the EDTA titration standard nomogram obtained in Example 1;

[0021] Figure 2 This is a schematic diagram of the principle of rapid on-site measurement of cement content obtained in Example 1;

[0022] Figure 3 It is the EDTA titration standard nomogram obtained in Example 2;

[0023] Figure 4 This is a schematic diagram of the principle of rapid on-site measurement of cement content obtained in Example 2. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0025] The cement dosage detection method of the ultra-large particle size cement-stabilized crushed stone of the present invention is specifically implemented according to the following steps:

[0026] Step 1, mixing cement-stabilized gravel with cement dosages of 0%, 1%, 3% and 5% (mass percentage) at test temperatures of 15° C., 20° C., 25° C., 30° C. and 35° C. according to the optimal moisture content of cement-stabilized gravel;

[0027] Step 2, passing the mixed cement-stabilized gravel mixtures with different dosages through a 4.75 mm sieve;

[0028] Step 3, take 300g of the sieved mixture in step 2 and put it into an enamel cup, stir the lumps with a stirring rod, then add 600mL of 10% ammonium chloride solution, and perform an EDTA titration test. After the solution turns rose red, record the EDTA solution consumption of the mixture solution with different cement dosages;

[0029] Step 4: According to the cement dosage (P si ) and EDTA solution consumption (V si ) between the standard curves and draw the EDTA titration fanomorph diagram;

[0030] Step 5, when measuring the cement dosage of the cement-stabilized crushed stone mixture at the construction site, 3000 g of a representative sample is taken and sieved to obtain a cement mortar sample;

[0031] Step 6, take 300g of cement mortar sample and put it into an enamel cup, stir the lumps with a stirring rod, then add 600mL of 10% ammonium chloride solution, perform EDTA titration test, and record the EDTA solution consumption after the solution turns rose red;

[0032] Step 7, according to the EDTA solution consumption of the cement mortar sample and the test environment temperature, the cement content of the cement-stabilized crushed stone actually measured in the on-site construction is obtained through the EDTA titration Fanomorph diagram.

[0033] Example 1

[0034] The cement dosage detection method of the ultra-large particle size cement-stabilized crushed stone of the present invention is specifically implemented according to the following steps:

[0035] Step 1, mixing cement-stabilized gravel with cement dosages of 0%, 1%, 3% and 5% at test temperatures of 15°C, 20°C, 25°C, 30°C and 35°C according to the optimal moisture content of cement-stabilized gravel;

[0036] Step 2, passing the mixed cement-stabilized gravel mixtures with different dosages through a 4.75 mm sieve;

[0037] Step 3: Take 300 g of the sieved mixture from step 2 and put it into an enamel cup. Use a stirring rod to break up the lumps. Then add 600 mL of 10% ammonium chloride solution and perform an EDTA titration test. When the solution turns rose red, record the EDTA solution consumption (V) of the mixture solution with different cement dosages. si );

[0038] Step 4: According to the cement dosage (P si ) and EDTA solution consumption (V si ) between the standard curves, and draw the EDTA titration fanomodulator diagram, such as Figure 1 As shown;

[0039] Step 5, when measuring the cement dosage of the cement-stabilized crushed stone mixture at the construction site, 3000 g of a representative sample is taken and sieved to obtain a cement mortar sample;

[0040] Step 6: Take 300g of cement mortar sample and put it into an enamel cup. Use a stirring rod to break up the lumps. Then add 600mL of 10% ammonium chloride solution and perform EDTA titration test. When the solution turns rose red, record the EDTA solution consumption (V si ) is 10.5 mL, and the test environment temperature is 26°C;

[0041] Step 7: Based on the EDTA solution consumption of the cement mortar sample and the test environment temperature, Figure 2 As shown, according to the EDTA titration standard nomogram, it can be obtained that the cement dosage of cement stabilized gravel measured on-site construction is 3.48%, while the cement dosage of cement stabilized gravel mixture sampled and measured is 3.82%. Compared with the actual cement dosage of 3.5% added to the cement stabilized gravel mixture, the method of the present invention significantly improves the measurement accuracy of cement dosage of cement stabilized gravel.

[0042] Example 2

[0043] The cement dosage detection method of the ultra-large particle size cement-stabilized crushed stone of the present invention is specifically implemented according to the following steps:

[0044] Step 1, mixing cement-stabilized gravel with cement dosages of 0%, 1%, 3% and 5% at test temperatures of 15°C, 20°C, 25°C, 30°C and 35°C according to the optimal moisture content of cement-stabilized gravel;

[0045] Step 2, passing the mixed cement-stabilized gravel mixtures with different dosages through a 4.75 mm sieve;

[0046] Step 3: Take 300 g of the sieved mixture from step 2 and put it into an enamel cup. Use a stirring rod to break up the lumps. Then add 600 mL of 10% ammonium chloride solution and perform an EDTA titration test. When the solution turns rose red, record the EDTA solution consumption (V) of the mixture solution with different cement dosages. si );

[0047] Step 4: According to the cement dosage (P si ) and EDTA solution consumption (V si ) between the standard curves, and draw the EDTA titration fanomodulator diagram, such as Figure 2 As shown;

[0048] Step 5, when measuring the cement dosage of the cement-stabilized crushed stone mixture at the construction site, 3000 g of a representative sample is taken and sieved to obtain a cement mortar sample;

[0049] Step 6: Take 300g of cement mortar sample and put it into an enamel cup. Use a stirring rod to break up the lumps. Then add 600mL of 10% ammonium chloride solution and perform EDTA titration test. When the solution turns rose red, record the EDTA solution consumption (V si ) is 9.8 mL, and the test environment temperature is 33 ° C;

[0050] Step 7: Based on the EDTA solution consumption of the cement mortar sample and the test environment temperature, Figure 4As shown, according to the EDTA titration standard nomogram, it can be obtained that the cement dosage of cement-stabilized gravel measured on-site construction is 2.55%, while the cement dosage of cement-stabilized gravel mixture sampled and measured is 2.82%. Compared with the actual cement dosage of 2.5% added to the cement-stabilized gravel mixture, the method of the present invention significantly improves the measurement accuracy of cement dosage of cement-stabilized gravel.

[0051] The above description shows and describes several preferred embodiments of the invention, but as mentioned above, it should be understood that the invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art shall be within the scope of protection of the claims attached to the invention without departing from the spirit and scope of the invention.

Claims

1. A cement dosage detection method for ultra-large particle size cement stabilized crushed stone, characterized in that: Specific steps to implement: Step 1, mixing cement-stabilized gravel with different cement dosages according to the optimal moisture content of cement-stabilized gravel at different test temperatures; Step 2, sieving the cement-stabilized gravel mixtures with different dosages; Step 3, take the undersize mixture after sieving in step 2 and put it into an enamel cup, stir the lumps with a stirring rod, then add 10% ammonium chloride solution, and perform an EDTA titration test. After the solution turns rose red, record the EDTA solution consumption of the mixture solution with different cement dosages; wherein every 100g of undersize mixture corresponds to 200ml of 10% ammonium chloride solution; Step 4, drawing an EDTA titration Fanograph according to the standard curve relationship between cement dosage and EDTA solution consumption at different test temperatures; Step 5, when measuring the cement dosage of the cement-stabilized crushed stone mixture at the construction site, a representative sample is taken and sieved to obtain a cement mortar sample; Step 6, take the cement mortar sample and put it into an enamel cup, use a stirring rod to break up the lumps, then add 10% ammonium chloride solution, perform EDTA titration test, and record the EDTA solution consumption after the solution turns rose red; Step 7, according to the EDTA solution consumption of the cement mortar sample and the test environment temperature, the cement content of the cement-stabilized crushed stone actually measured in the on-site construction is obtained through the EDTA titration Fanomorph diagram.

2. The cement dosage detection method for super-large particle size cement-stabilized crushed stone according to claim 1 is characterized in that: In step 1, the different test temperatures are 15°C, 20°C, 25°C, 30°C and 35°C.

3. The cement dosage detection method for super-large particle size cement-stabilized crushed stone according to claim 2 is characterized in that: In step 1, the cement-stabilized crushed stone with different cement dosages are 0%, 1%, 3% and 5% respectively.

4. The cement dosage detection method for super-large particle size cement-stabilized crushed stone according to claim 3 is characterized in that: In step 2 and step 5, the product is passed through a 4.75 mm sieve.

5. The cement dosage detection method for super-large particle size cement-stabilized crushed stone according to claim 4 is characterized in that: In step 5, the mixture is sieved through a 4.75 mm sieve.

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