阅读说明：本技术 含胶凝材料的乳化沥青混合料级配验证方法 (Emulsified asphalt mixture gradation verification method containing cementing material ) 是由 林江涛 樊亮 李永振 姜峰 魏慧� 周圣杰 侯佳林 毕飞 马士杰 韦金城 夏雨 于 2019-11-11 设计创作，主要内容包括：本发明公开了一种含胶凝材料的乳化沥青混合料级配验证方法,属于道路工程试验领域。该方法对标准混合料及现场混合料分别进行级配计算,以实现对现场混合料的级配验证,包括：a.确定混合料所用胶凝材料筛孔通过率；b.除去混合料中的沥青,得到抽提料；c.确定抽提料中胶凝材料的含量；d.不小于0.075mm的集料清洗后,进行筛分试验；e.进行级配计算,对混合料级配进行验证。与现有技术相比,本发明的含胶凝材料的乳化沥青混合料级配验证方法消除了胶凝材料的影响,具有可信度高、适用性强等特点,具有很好的推广应用价值。(The invention discloses a method for verifying the gradation of an emulsified asphalt mixture containing a cementing material, belonging to the field of road engineering tests. The method respectively carries out grading calculation on the standard mixture and the field mixture to realize the grading verification of the field mixture, and comprises the following steps: a. determining the sieve mesh passing rate of the cementing material used for the mixture; b. removing asphalt in the mixture to obtain an extraction material; c. determining the content of the cementing material in the extraction material; d. after cleaning the aggregate with the particle size of not less than 0.075mm, carrying out a screening test; e. and carrying out gradation calculation and verifying the gradation of the mixture. Compared with the prior art, the emulsified asphalt mixture gradation verification method containing the cementing material eliminates the influence of the cementing material, has the characteristics of high reliability, strong applicability and the like, and has good popularization and application values.)

1. The gradation verification method of the emulsified asphalt mixture containing the cementing material is characterized in that the gradation calculation is respectively carried out on the standard mixture and the field mixture to realize the gradation verification of the field mixture,

the standard mixture is prepared by emulsified asphalt raw materials which are actually applied on site,

the grading calculation method comprises the following steps:

a. determining the sieve pore passing rate of a cementing material used by the mixture, wherein the cementing material is cement and/or lime;

b. removing asphalt in the mixture to obtain an extraction material, wherein the extraction material is divided into a powder material with the particle size of less than 0.075mm and an aggregate with the particle size of not less than 0.075 mm;

c. determining the content of the cementing material in the extraction material;

d. after cleaning the aggregate with the particle size of not less than 0.075mm, carrying out a screening test;

e. and carrying out gradation calculation and verifying the gradation of the mixture.

2. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 1, characterized in that: and step b, removing the asphalt in the mixture by adopting an extraction test, and collecting powder materials with the thickness less than 0.075mm in the extraction test process, wherein the powder materials comprise aggregates with the thickness less than 0.075mm and gelled materials with the thickness less than 0.075 mm.

3. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 1, characterized in that: and step c, determining the content of the cementing material in the extraction material by an EDTA titration test.

4. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 1, characterized in that: and d, screening by adopting a dry screening method in the screening test of the step d.

5. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 4, characterized in that: the aggregate with the thickness not less than 0.075mm is cleaned by a special cleaning device, the special cleaning device comprises a cleaning box, a cleaning cover, a cleaning nozzle, a water drain pipe and an ultrasonic vibrator,

the washing cover lock joint is in wasing the uncovered department in case top, and the washing terminals sets up in washing the cover to with the inlet tube intercommunication, wash the case lower extreme and connect the outlet pipe, the mouth of pipe department of outlet pipe is provided with screen cloth and the stopper that the sieve mesh size is 0.075mm, is provided with a plurality of ultrasonic vibrator on the washing tank wall.

6. The emulsified asphalt mixture gradation verification method containing a cementitious material as claimed in claim 5, wherein: still include the sewage purification pond, the sewage purification pond middle part is provided with filtering mechanism, and filtering mechanism separates the sewage purification pond for sewage side and water purification side, and the sewage side is through wash-out pipe and washing case intercommunication, and the water purification side passes through wet return, water pump and three-way valve and connects the inlet tube of washing terminals.

7. The emulsified asphalt mixture gradation verification method containing a cementitious material as claimed in claim 6, wherein: the filtering mechanism consists of a frame, a filtering plate and a limiting slot, the limiting slot is fixed on the side wall and the bottom of the sewage purifying tank, the outer edge of the frame is inserted into the limiting slot, and the filtering plate is fixed in the frame.

8. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 5 or 6, characterized in that:

the screen is of a barrel-shaped structure, the upper end of the screen is open, the screen is lapped at the pipe orifice of the water drain pipe of the cleaning tank and is positioned by a snap ring, the lower end of the screen is inserted into the water drain pipe of the cleaning tank,

the plug is inserted into the opening of the drain pipe of the cleaning box, and the bottom surface of the plug is contacted with the top end of the snap ring.

9. The emulsified asphalt mixture gradation verification method containing a cementitious material according to claim 1, characterized in that: and e, determining the grading of the mixture on site by combining the content of the cementing material and the screening data, and calculating the final screening result according to a water screening method.

10. The emulsified asphalt mixture gradation verification method containing a cementitious material as claimed in claim 5, wherein:

the sub-0.075 mm portion does not include sub-0.075 mm cement, calculated as a gradation.

Technical Field

The invention relates to the field of road engineering, and particularly provides a method for verifying the gradation of an emulsified asphalt mixture containing a cementing material.

Background

The emulsified asphalt mixture is widely used in the field of road engineering, such as micro-surfacing, cold recycling and the like, and with the improvement of the emulsified asphalt technology, the application range of the emulsified asphalt mixture in a pavement structure layer is continuously expanded. The gradation of the mixture is an important factor influencing the quality stability of the mixture, which requires technical personnel to carry out gradation inspection on the mixture produced actually, but the gradation inspection of the emulsified asphalt mixture has the following problems:

firstly, the hot-mix mixture is specified in detail in the country at present, but the grading inspection method for the emulsified mixture is unclear, for example, the micro-surfacing asphalt mixture is inspected through the consumption of each grade after large-area construction is adopted at present, and the mixture is often premixed during large-scale construction actually, so that the method is extremely rough and inaccurate;

secondly, materials such as cement and lime are often required to be added into the emulsified asphalt mixture for production, for example, the addition amount of the cement in the mixture such as micro-surfacing is 0-3%, the hydration and other actions of cementing materials such as cement and lime enable the materials such as cement to be coagulated into small particles (which can be dispersed) or attached to the surface of aggregate, and a lot of testers directly perform screening tests without treatment or perform common water washing methods, so that the cleaning is time-consuming and has poor effect.

And thirdly, cement and lime are used as additives, the functions of the additives are different from the functions of mineral powder and other fillers, and the most part of the lime and the cement is added into mineral powder and other aggregates by the conventional grading method due to the fact that the particle size of the lime and the cement is 0.075 mm.

The operation mode directly causes serious deviation of the test result from the actual situation, and can not guide production. In the prior art, a grading screening verification method for emulsified asphalt mixtures containing cementing materials such as cement and lime is basically in a blank state.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides the emulsified asphalt mixture gradation verification method containing the cementing material, which has high reliability and strong applicability.

The technical scheme adopted by the invention for solving the technical problems is as follows: the gradation verification method of emulsified asphalt mixture containing cementing material is characterized by that it respectively makes gradation calculation for standard mixture and field mixture so as to implement gradation verification of field mixture,

the standard mixture is prepared by emulsified asphalt raw materials which are actually applied on site,

the grading calculation method comprises the following steps:

a. determining the sieve pore passing rate of a cementing material used by the mixture, wherein the cementing material is cement and/or lime;

b. removing asphalt in the mixture to obtain an extraction material, wherein the extraction material is divided into a powder material with the particle size of less than 0.075mm and an aggregate with the particle size of not less than 0.075 mm;

c. determining the content of the cementing material in the extraction material;

d. after cleaning the aggregate with the particle size of not less than 0.075mm, carrying out a screening test;

e. and carrying out gradation calculation and verifying the gradation of the mixture.

Preferably, step b removes the bitumen in the mix using an extraction test during which less than 0.075mm of powdered material is collected, said powdered material comprising less than 0.075mm aggregate and less than 0.075mm cementitious material. For example, filter paper can be used to collect powder material smaller than 0.075mm in the extraction test.

Step c preferably determines the amount of gelling material in the extract by EDTA titration test.

The screening test of the step d is preferably carried out by adopting a dry screening method.

As preferred, can adopt special belt cleaning device to wash not less than 0.075 mm's gathering materials, special belt cleaning device is including wasing the case, washing the cover, washing terminals, outlet pipe and ultrasonic vibrator, washing terminals lock joint is in washing the uncovered department in case top, and washing terminals sets up in washing the cover to with the inlet tube intercommunication, wash under the case and connect the outlet pipe, the mouth of pipe department of outlet pipe is provided with screen cloth and the stopper that the sieve mesh size is 0.075mm, is provided with a plurality of ultrasonic vibrator on the washing tank wall.

The flushing nozzle is preferably a shower nozzle.

The flushing cover is made of soft waterproof materials such as waterproof cloth, and when the materials are put in or taken out, the edge of the flushing cover is lifted.

The number of the ultrasonic vibrators is preferably 2-6, and the ultrasonic vibrators are uniformly distributed on the wall of the cleaning tank.

Further, belt cleaning device still includes the sewage purification pond, and the sewage purification pond middle part is provided with filtering mechanism, and filtering mechanism separates the sewage purification pond for sewage side and water purification side, and the sewage side is through wash-out pipe and washing case intercommunication, and the water purification side is through wet return, water pump and three-way valve and connect the inlet tube of washing terminals.

Preferably, the filtering mechanism consists of a frame, a filtering plate and a limiting slot, the limiting slot is fixed on the side wall and the bottom of the sewage purifying tank, the outer edge of the frame is inserted into the limiting slot, and the filtering plate is fixed in the frame.

In order to reduce the influence of the sewage side sediment on the filter plate, a height increasing base plate can be arranged in the sewage purification tank, and the filtering mechanism is arranged on the height increasing base plate.

The screen is preferably of a barrel-shaped structure, the upper end of the screen is open, the screen is lapped at the opening of a water drain pipe of the cleaning tank and is positioned through a snap ring, and the lower end of the screen is inserted into the water drain pipe of the cleaning tank.

The plug is inserted into the opening of the drain pipe of the cleaning box, and the bottom surface of the plug is contacted with the top end of the snap ring.

Furthermore, the cleaning device can also comprise a controller, wherein the controller is electrically connected with the ultrasonic vibrator, the water pump and the like and can be used for setting parameters such as cleaning time of the washing nozzle, frequency and time of ultrasonic operation and the like.

And e, determining the grading of the mixture on site by combining the content of the cementing material and the screening data, and calculating the final screening result according to a water screening method.

The sub-0.075 mm portion does not include sub-0.075 mm cement, calculated as a gradation.

The implementation mode of the emulsified asphalt mixture gradation verification method containing the cementing material provided by the invention comprises the following steps:

firstly, extracting emulsified asphalt raw materials actually applied on site and mixed site mixture, and carrying out the following tests:

1. sieving cement or lime raw material with sieve mesh passing rate of P_{Gelation, i}(％)；

2. Preparing emulsified asphalt standard mixture according to the addition amount of cement or lime such as different cement or lime;

dispersing the prepared standard mixture and the mixture extracted on site, putting the mixture into an oven with proper temperature for drying, weighing the mass (M1) of the dried mixture, and then carrying out an extraction test; wherein, the asphalt mixture extracted on site is divided into two parts which are respectively used for a titration test and a screening test;

and thirdly, recovering the extract material after the extraction test, wherein the extract material is divided into two parts, namely a powder material with the mass being less than 0.075mm and an aggregate with the mass being not less than 0.075mm, and the masses are respectively M2 and M3, wherein the recovery requirements are divided into 2 cases according to the purposes:

1. for the titration test, the part smaller than 0.075mm on the filter paper is recovered and mixed with the extracted aggregate (the aggregate not smaller than 0.075 mm) uniformly to carry out the titration test. Determining the content (omega%) of cement or lime in the field mixture according to an EDTA detection method;

2. for grading sieving, there is no need to recover a fraction of less than 0.075mm on the filter paper, which is directed to the field mix for the sieving test;

weighing dry aggregate with the mass (M3) not less than 0.075mm after extraction, and putting the dry aggregate into the special cleaning device for cleaning; after cleaning, putting the mixture into an oven for drying, weighing the mass (M4), and then testing the dried dry aggregate according to a dry screening method;

fifthly, determining the grading of the mixture on site by combining the content of cement or lime and screening data, and calculating the final screening result according to a water screening method, wherein,

1. actual content of asphalt:

2. the mass of materials such as cement or lime and the like:

m＝(M2+M3)×ω％；

3. the total mass M of the mineral aggregates after extraction, which is noted here as the number of calculations for the sieving test, is not to include the cement or lime fraction:

M＝(M2+M3)×(1-ω％)；

4. the mass of the 0.075mm sieve part in the synthetic grade does not contain the part smaller than 0.075mm in the cement or lime:

m_0.075＝M2+M3-M4-(M2+M3)×ω％×P_{gelation, 0.075}；

5. The content of particles smaller than 0.075mm in the synthetic composition does not comprise the part smaller than 0.075mm in the cement or lime:

the mixture P is mixed with the raw materials,

6. in the rest of the synthetic mineral aggregate, the data such as the mass of each grade, the screening passing rate and the like are calculated according to a water washing method specified by a standard specification.

Compared with the prior art, the emulsified asphalt mixture gradation verification method containing the cementing material has the following outstanding beneficial effects:

the influence of a cementing material is eliminated, the grading data of the emulsified asphalt mixture containing materials such as cement or lime can be accurately determined, and the emulsified asphalt mixture has high reliability and strong applicability;

secondly, the aggregate washing process is efficient and thorough, and the test accuracy is further guaranteed;

the bucket-shaped screen can avoid blockage, and the cleaning efficiency is further ensured;

and (IV) the cleaning water can be recycled, so that the energy is saved and the environment is protected.

Drawings

FIG. 1 is a schematic structural diagram of a special cleaning device of an embodiment;

FIG. 2 is a schematic structural view of a cleaning tank and related parts of the cleaning apparatus shown in FIG. 1;

FIG. 3 is an enlarged schematic view of the cleaning apparatus shown in FIG. 2 at A;

FIG. 4 is an enlarged schematic view of the cleaning apparatus shown in FIG. 1 at B;

FIG. 5 is a graph of the gradation verification of gradation 1 in example two;

FIG. 6 is a graph of the gradation 2 gradation verification in example two;

fig. 7 is a graph of the gradation 3 gradation verification in example two.

The reference numerals in the drawings denote:

1. the cleaning box comprises a cleaning box body, 2 parts of a cleaning cover, 3 parts of a cleaning spray head, 4 parts of an ultrasonic vibrator, 5 parts of a sewage purification tank, 6 parts of a controller, 7 parts of a water inlet pipe, 8 parts of a water drain pipe, 9 parts of a screen, 10 parts of a plug, 11 parts of a snap ring, 12 parts of a heightening base plate, 13 parts of a water return pipe, 14 parts of a water pump, 15 parts of a three-way valve, 16 parts of a frame, 17 parts of a filter plate, 18 parts of a limiting slot.

Detailed Description

The invention is further described with reference to the following figures and specific examples, which are not intended to be limiting.

In the present invention, the use of directional terms such as "upper, lower, left, right" generally means upper, lower, left, right as viewed with reference to the accompanying drawings, unless otherwise specified; "inner and outer" refer to the inner and outer relative to the profile of the components themselves.