A method for estimating the penetration depth of an emulsified asphalt primer

Abstract

The application discloses a kind of emulsified asphalt primer oil penetration depth estimation method, according to liquid penetration dynamics Lucas-Washburn equation, take the case when capillary action and liquid gravity size is equal, at this time, liquid is in equilibrium state, obtain the estimation equation of the maximum depth that liquid penetration can reach.And primer oil emulsified asphalt is used on cement stabilized macadam base, its penetration effect and the particle size of emulsified asphalt itself, demulsification time and the porosity of cement stabilized macadam base are all connected, this estimation method aims at adding suitable emulsified asphalt particle size index r, particle maximum packing rate formation time T to liquid penetration dynamics equation, and corresponding parameter is adjusted, and corresponding numerical value is measured and fitted, to form a penetration depth estimation equation that conforms to emulsified asphalt primer oil is used on cement stabilized macadam base.

Description

Technical Field

[0001] This invention belongs to the field of traffic road engineering technology, and in particular relates to a method for predicting the penetration depth of emulsified asphalt tack coat based on a modified permeability theory. Background Technology

[0002] Cement-stabilized crushed stone base course is a commonly used load-bearing layer in high-grade asphalt pavements. This type of base course meets the basic performance requirements for road load-bearing capacity and often uses soil, stone, and industrial waste as main raw materials, offering significant technical and economic advantages. However, the surface course uses asphalt-based materials, which are flexible materials. There are significant differences in modulus and performance between the two, contradicting the design expectation of a completely continuous base and surface course. Therefore, a tack coat is needed to strengthen the bond between the two. Simultaneously, the application of the tack coat also solidifies the cement-stabilized crushed stone base course, preventing damage from compaction during construction, and secondarily, it provides waterproofing.

[0003] Among the construction requirements for tack coats, the most important is the required penetration depth of the tack coat in cement-stabilized crushed stone. Sufficient penetration depth is essential to ensure the effective function of emulsified asphalt during road use. However, in practice, the penetration effect of tack coats is studied experimentally. The molding time for cement-stabilized crushed stone specimens is relatively long, and the uneven penetration effect of the emulsified asphalt on the base surface, as well as its inability to accurately measure the penetration depth when applied to overly dense base structures, all affect the evaluation of the tack coat's penetration performance. Therefore, this study will investigate and determine the relevant indicators affecting the penetration performance of emulsified asphalt, and fit a predictive equation suitable for the penetration depth of emulsified asphalt, providing guidance for research on the penetration performance of emulsified asphalt. Summary of the Invention

[0004] Technical problems solved: Existing technologies suffer from problems such as long molding times for water-stabilized crushed stone specimens, uneven penetration of tack coat emulsified asphalt on the base layer surface, and inaccurate measurement of penetration depth when applied to overly dense base structures, all of which affect the evaluation of tack coat penetration performance. This invention provides a method for estimating the penetration depth of tack coat emulsified asphalt based on a modified penetration theory. Unlike traditional methods that wait for the emulsified asphalt to break down before observing the penetration depth, this method derives the maximum penetration depth of the tack coat by quickly measuring the porosity and contact angle of the water-stabilized crushed stone base layer, thus providing a preliminary understanding of the tack coat's penetration effect.

[0005] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0006] A method for predicting the penetration depth of emulsified asphalt tack coat based on a modified penetration theory includes the following steps:

[0007] Step 1, the equation for predicting the penetration depth of the emulsified asphalt tack coat is:

[0008] Where: h - penetration depth (mm);

[0009] θ - contact angle, °;

[0010] ρ - density, kg / m³ 3 ;

[0011] g - acceleration due to gravity, g / m 2 ;

[0012] T - Time to form maximum particle packing ratio, h;

[0013] P-Porosity of water-stabilized crushed stone specimen, %;

[0014] r - particle size, μm;

[0015] η - Dynamic viscosity, MPa·s

[0016] a, b, c, d, e, f - parameters to be fitted;

[0017] Step 2: Measure the particle size index D of the emulsified asphalt using a laser particle size analyzer. 50 And use it as the particle size index r in the prediction equation;

[0018] Step 3: Use the room temperature drying film-forming method to obtain the moisture change curve during the drying film-forming process by timed weighing. According to the theory of emulsified asphalt drying film-forming and the moisture change, the change curve is divided into three stages: particle filling stage, demulsification stage and asphalt film formation stage. The intersection of the fitted curve of the particle filling stage and the fitted line of the asphalt film formation stage is the time T at which the particle maximum bulking rate is located, and it is added to the prediction equation.

[0019] Step 4: Measure the open porosity of the water-stabilized specimen using the immersion method. The specific method is as follows: First, weigh the original weight of the water-stabilized specimen and record it as M1. Then, place a bucket with a water outlet at the top on an electronic scale and continuously add water until the mass no longer increases. At this point, zero the electronic scale. Next, slowly place the water-stabilized specimen into the bucket, ensuring that water can only flow out through the top outlet. Let it stand, then slowly add water until no more bubbles appear and the mass on the electronic scale no longer changes after adding water. Record this mass as M2. Then, calculate the open porosity of the specimen according to Formula 2.

[0020]

[0021] In the formula: P o —Open porosity of water-stabilized specimens, %;

[0022] M1—Original mass of the water-stabilized specimen, g;

[0023] M2—Mass of the water-stable specimen after deducting buoyancy, in grams;

[0024] V s —Volume of water-stabilized specimen, cm 3 ;

[0025] ρ w —Density of water, kg / m³ 3

[0026] Where M1-M2 represents the mass of water displaced from the solid portion of the water-stabilized specimen, dividing this mass by the density of water yields the volume of the solid portion. For V... s Neglecting wear loss on the water-stabilized specimen, and assuming a diameter D = 15 cm and a height H = 15 cm, the final volume is calculated to be 2649.4 cm³. 3 ;

[0027] Step 5: Measure the contact angle θ of the emulsified bitumen prime coat to be tested using an optical contact angle meter;

[0028] Step 6: Measure the density ρ of the permeate oil using a density bottle;

[0029] Step 7: Use a Brookfield viscometer to test the viscosity of the experimental sample to obtain the dynamic viscosity of the emulsified asphalt;

[0030] Step 8: Determine the penetration depth of emulsified asphalt using the press destructive method;

[0031] Step 9: Select various emulsified asphalts, measure the required values ​​according to steps 2-8, and substitute them into the equation. In the process, appropriate fitting is performed to determine the parameters to be fitted;

[0032] Step 10: Obtain the corresponding values ​​of the emulsified asphalt for which the required penetration depth needs to be estimated according to steps 2 to 8 above, and substitute them into the estimation equation to obtain the estimated maximum penetration depth of the tack coat.

[0033] Preferably, the tack coat emulsified asphalt is used on a cement-stabilized crushed stone base course. The emulsified asphalt particle size index *r* and the time to maximum particle packing ratio *T* are incorporated into the liquid permeation kinetics equation. Since surface tension and contact angle have a strong correlation in the formula, this parameter is no longer considered for the purpose of simplifying the equation. Furthermore, because the emulsified asphalt is applied to the surface of the cement-stabilized crushed stone base course, the crack width *R* in the permeation kinetics equation is... dFor cement-stabilized crushed stone, pore size is more appropriate. However, since the pore distribution of cement-stabilized crushed stone base is relatively random and not very uniform, porosity P is used instead of R. d Furthermore, considering that the original equation analyzes the upward seepage of liquid on the lower surface through capillary action, which is opposite to the direction of seepage of emulsified asphalt sprayed on cement-stabilized crushed stone base course, but considering that the corresponding influencing factors are applicable to emulsified asphalt, the corresponding influencing factors in this formula can be retained, and P can be placed on the molecule.

[0034] Preferably, in step 1, according to Poiseuille's law, the formula for the liquid permeation rate, which represents the balance between viscous force, capillary action, and hydrostatic force, is: In the formula, v = permeation rate, dh = change in permeation depth, dt = change in permeation time, and R... d = Crack width, η = Dynamic viscosity, h = Penetration depth; Permeability pressure difference In the formula, σ = surface tension: R d = Crack width, θ = Contact angle, ρ = Density, g = Gravitational acceleration; then substitute ΔP into the permeation rate to obtain the classic Lucas-Washburn equation for fluid permeation dynamics. In the formula, r = particle size, t = infiltration time; when capillary action and liquid gravity are equal (ΔP = 0), the liquid is in equilibrium, which is the maximum depth that infiltration can reach.

[0035] Preferably, the specific steps for measuring the penetration depth of emulsified asphalt using the press destructive method are as follows:

[0036] (1) Spray emulsified asphalt on the surface of the water-stabilized crushed stone base after curing, and after standing for 3 days, cover the upper surface of the water-stabilized crushed stone specimen with a piece of paper.

[0037] (2) Place the water-stabilized specimen on the press and press it at a rate of 2 mm / min until cracks appear on the surface of the specimen and it becomes loose, but avoid it from falling apart as a whole.

[0038] (3) Divide the specimen into four equal parts longitudinally, and break the aggregate by hand according to the original composition of the specimen;

[0039] (4) Take three pieces from each part, for a total of 12 pieces, and average the values ​​of the 12 pieces. Take the final average value as the final representative penetration depth.

[0040] Preferably, in step 4, the water-stable specimen is slowly placed into the bucket, ensuring that water can only flow out through the top outlet, and then left to stand. During this period, bubbles will continuously rise to the top, and the mass will decrease accordingly. This is the manifestation of water replacing the air in the pores of the specimen opening. Then, water is slowly added until no more bubbles rise and the mass on the electronic scale no longer changes after adding water. The mass at this point is recorded as M2.

[0041] Beneficial effects

[0042] The present invention has the following advantages over the prior art:

[0043] 1. The preparation of cement-stabilized crushed stone base course is a large-scale and time-consuming process, therefore the time required to test the penetration depth of emulsified asphalt is also relatively long.

[0044] 2. When the density of the cement-stabilized crushed stone base course is high, most of the emulsified asphalt cannot fully penetrate, resulting in an inaccurate and subjective evaluation of the permeability performance of the emulsified asphalt material.

[0045] 3. The original permeation kinetic equation did not consider the relevant indicators of emulsified asphalt, resulting in poor accuracy of the test results for the penetration depth of emulsified asphalt. Attached image description:

[0046] Figure 1 This is a penetration testing schematic diagram of this application;

[0047] Figure 2 This is a schematic diagram of the film formation during room temperature drying according to this application;

[0048] Figure 3 This is a schematic diagram of the emulsified asphalt drying process of this application;

[0049] Figure 4 This is a schematic diagram of the immersion method used in this application;

[0050] Figure 5 This is a schematic diagram of the press failure method of this application. Detailed Implementation

[0051] The technical solution of the present invention will be described in detail below:

[0052] Example 1

[0053] A method for predicting the penetration depth of emulsified asphalt tack coat based on a modified penetration theory includes the following steps:

[0054] Step 1: According to Poiseuille's law, neglecting the effect of osmotic inertia, the formula for the liquid permeation rate, representing the balance between viscous force, capillary action, and hydrostatic force, is: In the formula, v = permeation rate, dh = change in permeation depth, dt = change in permeation time, and R...d = Crack width, η = Dynamic viscosity, h = Penetration depth; Permeability pressure difference In the formula, σ = surface tension: R d = Crack width, θ = Contact angle, ρ = Density, g = Gravitational acceleration; then substitute ΔP into the permeation rate to obtain the classic Lucas-Washburn equation for fluid permeation dynamics. In the formula, r = particle size, t = infiltration time; when capillary action and liquid gravity are equal (ΔP = 0), the liquid is in equilibrium, which is the maximum depth that infiltration can reach. In contrast to tack coat emulsified asphalt, which needs to be applied to a cement-stabilized crushed stone base course, its penetration effect is related to the particle size of the emulsified asphalt itself, the demulsification time, and the porosity of the cement-stabilized crushed stone base course. Therefore, the particle size index r of the emulsified asphalt and the time T for the formation of the maximum particle packing ratio need to be added to the liquid penetration kinetics equation. Surface tension and contact angle in the formula have a strong correlation; for the purpose of simplifying the equation, surface tension is no longer considered. Furthermore, since the emulsified asphalt is applied to the surface of the cement-stabilized crushed stone base course, the crack width R in the penetration kinetics equation... d For cement-stabilized crushed stone, pore size is more appropriate. However, since the pore distribution of cement-stabilized crushed stone base is relatively random and not very uniform, porosity P is used instead of R. d Furthermore, considering that the original equation analyzes the upward seepage of liquid from the lower surface through capillary action, which is opposite to the infiltration direction of emulsified asphalt sprayed on cement-stabilized crushed stone base course, but considering that the corresponding influencing factors are applicable to emulsified asphalt, the corresponding influencing factors in this formula can be retained. At the same time, P is placed in the molecule, and finally the equation for predicting the penetration depth of emulsified asphalt prime coat is:

[0055] Where: h - penetration depth (mm);

[0056] θ - contact angle, °;

[0057] ρ - density, kg / m³ 3 ;

[0058] g - acceleration due to gravity, g / m 2 ;

[0059] T - Time to form maximum particle packing ratio, h;

[0060] P-Porosity of water-stabilized crushed stone specimen, %;

[0061] r - particle size, μm;

[0062] η - Dynamic viscosity, MPa·s

[0063] a, b, c, d, e, f - parameters to be fitted.

[0064] Step 2: As attached Figure 1 As shown, the average particle size of emulsified asphalt particles affects its penetration effect on cement-stabilized crushed stone base courses to a certain extent. Therefore, a laser particle size analyzer was used to measure the particle size index D of the emulsified asphalt. 50 And it is used as the particle size index r in the prediction equation.

[0065] Step 3: The maximum bulk density of emulsified asphalt particles refers to the maximum bulk density reached when the asphalt particles aggregate and come into contact as the water in the emulsified asphalt continuously evaporates. At this point, the emulsified asphalt and aggregate have the strongest adhesion, and the emulsified asphalt no longer penetrates further, reaching its maximum penetration depth. The longer it takes to reach this state, the longer the demulsification time, and the more time the emulsified asphalt has for the penetration process, resulting in a greater penetration depth. This is achieved using the room temperature drying film-forming method (taking...). Figure 2 The samples shown in the third part of the image were placed in a curing chamber for drying tests (temperature 20℃, humidity 15%, wind speed 0.4m / s). The moisture change curve during the drying and film formation process was obtained using a timed weighing method. Based on the theory of emulsified asphalt drying and film formation and the moisture change, the curve was divided into three stages: particle filling stage, demulsification stage, and asphalt film formation stage. The intersection of the fitted curve for the particle filling stage and the fitted line for the asphalt film formation stage represents the time T at which the maximum particle bulk ratio occurs, and this value was added to the prediction equation. The test method is detailed in the appendix. Figure 2 Theoretically, comparing the drying and film formation of emulsified asphalt before and after reaching maximum bulk density, asphalt particles continuously aggregate, indicating a significant change in the evaporation rate. The change in evaporation rate should be greatest at the time point corresponding to maximum particle bulk density, which corresponds to the smallest radius of curvature on the evaporation curve. However, the exact function of the drying curve is unknown. Therefore, it is necessary to calculate the time of maximum particle bulk density by using the intersection of the first-stage fitted curve and the third-stage fitted line. See the appendix for specific instructions. Figure 3 And add it to the prediction equation.

[0066] Step 4: Measure the open porosity of the water-stabilized specimen using the immersion method. Specifically, first weigh the original weight of the water-stabilized specimen and record it as M1. Then take the attached... Figure 4A bucket (with a spout at the top) is placed on an electronic scale, and water is continuously added until the mass stops increasing. At this point, the scale is zeroed. Next, the water-stable specimen is slowly placed into the bucket, ensuring that water can only flow out through the top spout. It is then allowed to stand. During this time, bubbles will continuously rise to the top, and the mass will decrease accordingly. This indicates that water is replacing air in the pores of the specimen. Water is then slowly added until no more bubbles rise, and the mass on the scale no longer changes after adding water. The mass at this point is recorded as M2. Then, the pore size of the specimen is calculated using Formula 2:

[0067]

[0068] In the formula: P o —Open porosity of water-stabilized specimens, %;

[0069] M1—Original mass of the water-stabilized specimen, g;

[0070] M2—Mass of the water-stable specimen after deducting buoyancy, in grams;

[0071] V s —Volume of water-stabilized specimen, cm 3 ;

[0072] ρ w —Density of water, kg / m³ 3

[0073] Where M1-M2 represents the mass of water displaced from the solid portion of the water-stabilized specimen, dividing this mass by the density of water yields the volume of the solid portion. For V... s Neglecting wear loss on the water-stabilized specimen, and assuming a diameter D = 15 cm and a height H = 15 cm, the final volume is calculated to be 2649.4 cm³. 3 .

[0074] Step 5: Use an optical contact angle meter to measure the contact angle θ of the emulsified bitumen prime coat to be tested.

[0075] Step 6: Measure the density ρ of the permeate oil using a density bottle.

[0076] Step 7: Use a Brookfield viscometer to test the viscosity of the experimental sample to obtain the dynamic viscosity of the emulsified asphalt.

[0077] Step 8: The penetration depth of emulsified asphalt is measured using the pressure crushing method. The specific steps are as follows:

[0078] (1) Spray emulsified asphalt on the surface of the water-stabilized crushed stone base after curing. After standing for 3 days, cover the upper surface of the water-stabilized crushed stone specimen with a piece of paper. This operation is to ensure that the specimen is subjected to uniform stress and achieve overall looseness of the specimen. On the other hand, it can also prevent the press from sticking with the emulsified asphalt that has not dried.

[0079] (2) Place the water-stabilized specimen on the press and press it at a rate of 2 mm / min until cracks appear on the surface of the specimen and it becomes loose, but avoid it from falling apart as a whole.

[0080] (3) Divide the specimen into four equal parts longitudinally, and break the aggregate apart by hand according to the original structure of the specimen, trying to follow the original texture as much as possible, otherwise the actual value of the penetration depth will be reduced.

[0081] (4) Take three pieces from each section, for a total of 12 pieces. Measure the depth of emulsified asphalt in the broken aggregates with a ruler, and average the values ​​from the 12 pieces. Take the final average value as the final representative penetration depth. See the attached diagram. Figure 5 .

[0082] Step 9: Prepare various emulsified asphalts according to Table 1, measure the required values ​​according to steps 2-8, and substitute them into the equation. In the process, appropriate fitting is performed to determine the parameters to be fitted.

[0083] Table 1. Preparation conditions of emulsified asphalt

[0084]

[0085] The penetration depth of each group is shown in Table 2:

[0086] Table 2. Penetration depth of emulsified asphalt in each control group.

[0087]

[0088] Then, the corresponding test data were fitted to determine the values ​​of the parameters to be determined. The specific results are shown in Table 3, and the correlation indicators are shown in Table 4.

[0089] Table 3. Parameters after fitting the permeability equation.

[0090]

[0091] Table 4 Correlation parameters of the fitted equation

[0092]

[0093] As can be seen from the fitting results, the correlation coefficient R 2 The correlation coefficient reached 0.98, indicating a high correlation. Therefore, the fitted equation is shown in Formula 3:

[0094]

[0095] Step 10: Obtain the corresponding values ​​according to steps 2 to 8 above, and substitute them into formula 3 to obtain the estimated maximum penetration depth of the tack coat oil.

[0096] Example 2

[0097] A method for predicting the penetration depth of emulsified asphalt tack coat based on a modified penetration theory is proposed. Three commonly available emulsified asphalts are selected, and five parallel tests are conducted for each control group. The asphalt is applied to cement-stabilized crushed stone with a suspended dense structure cured for 1 day, 7 days, and a skeleton dense structure cured for 7 days, respectively. The required values ​​in the formula are measured, and the average of the five sets of calculated and test results is taken. The method includes the following steps:

[0098] Step 1: Measure the contact angle θ of the emulsified bitumen prime coat to be tested using an optical contact angle meter;

[0099] Step 2: Use a laser particle size analyzer to measure the particle size index D of the test sample. 50 ;

[0100] Step 3: Use a Brookfield viscometer to test the viscosity of the experimental sample and calculate the dynamic viscosity of the emulsified asphalt.

[0101] Step 4: Measure the density of the emulsified asphalt prime coat using a density bottle;

[0102] Step 5: The porosity of the cement-stabilized crushed stone base layer was tested by measuring the change in mass of the cement-stabilized crushed stone before and after immersion in water.

[0103] Step 6: The formation time of maximum particle bulk density of emulsified asphalt was tested using the room temperature drying film-forming method;

[0104] Step 7: Substitute all the measured data into the formula That is, to obtain the estimated maximum penetration depth of the tack oil.

[0105] The test results are shown in Table 5:

[0106] Table 5 Calculated and tested values ​​of relevant indicators for emulsified asphalt

[0107]

[0108] Test results show that the error values ​​of the three test groups are all within 15%. The main reason for the error is that the test results of emulsified asphalt itself have a large margin of error. However, the permeability of emulsified asphalt can still be roughly estimated and judged, which is of guiding significance for the evaluation system of emulsified asphalt permeability.

Claims

1. A method for predicting the penetration depth of emulsified asphalt prime coat, characterized in that, Includes the following steps: Step 1, the equation for predicting the penetration depth of the emulsified asphalt tack coat is: Formula 1; In the formula: h -Penetration depth, mm; θ -Contact angle, °; ρ - Density, kg / m³ 3 ; g - Gravitational acceleration, m / s² 2 ; T - Time to achieve maximum particle packing ratio, h; P -Porosity of water-stabilized crushed stone specimen, % r -Particle size, μm; η - Dynamic viscosity, MPa·s a, b, c, d, e, f - Parameters to be fitted; Step 2: Measure the particle size index D of the emulsified asphalt using a laser particle size analyzer. 50 And use it as the particle size index in the prediction equation. r ; Step 3: Using the room temperature drying film-forming method, obtain the moisture change curve during the drying film-forming process by timed weighing. Based on the theory of emulsified asphalt drying film-forming and the moisture change situation, the change curve is divided into three stages: particle filling stage, demulsification stage, and asphalt film formation stage. The intersection of the fitted curve of the particle filling stage and the fitted curve of the asphalt film formation stage is the time when the particle bulk ratio is at its maximum. T And add it to the prediction equation; Step 4: Measure the open porosity of the water-stabilized specimen using the immersion method. Specifically, first weigh the original weight of the water-stabilized specimen and record it as M1. Then, place a bucket with an outlet at the top on an electronic scale and continuously add water until the mass no longer increases. At this point, zero the electronic scale. Next, slowly place the water-stabilized specimen into the bucket, ensuring that water can only flow out through the top outlet. Let it stand, then slowly add water until no more bubbles appear and the mass on the electronic scale no longer changes after adding water. Record this mass as M2. Then, calculate the open porosity of the specimen according to Formula 2. Official 2; In the formula: P o —Open porosity of water-stabilized specimens, % M 1 — Original mass of the water-stabilized specimen, g; M 2—Mass of the water-stabilized specimen after deducting buoyancy, in grams; V s —Volume of water-stabilized specimen, cm 3 ; ρ w —Density of water, kg / m³ 3 Where M1-M2 represents the mass of water displaced from the solid portion of the water-stabilized specimen, dividing this mass by the density of water yields the volume of the solid portion. V s Neglecting wear loss on the water-stabilized specimen, and assuming a diameter D = 15 cm and a height H = 15 cm, the final volume is calculated to be 2649.4 cm³. 3 ; Step 5: Use an optical contact angle meter to measure the contact angle of the emulsified asphalt prime coat to be tested. θ Measurement; Step 6: Measure the density of the permeate oil using a density bottle. ρ Perform measurements; Step 7: Use a Brookfield viscometer to test the viscosity of the experimental sample to obtain the dynamic viscosity of the emulsified asphalt; Step 8: Determine the penetration depth of emulsified asphalt using a pressure testing method; Step 9: Select various emulsified asphalts, measure the required values ​​according to steps 2-8, and substitute them into the equation. In the process, appropriate fitting is performed to determine the parameters to be fitted; Step 10: Obtain the corresponding values ​​of the emulsified asphalt for which the required penetration depth is to be estimated according to steps 2 to 8 above, and substitute them into the estimation equation to obtain the estimated maximum penetration depth of the tack coat.

2. The method for predicting the penetration depth of emulsified asphalt tack coat according to claim 1, characterized in that: The emulsified asphalt tack coat is used on a cement-stabilized crushed stone base course, and the emulsified asphalt particle size index is... r Time to formation of maximum particle packing ratio T The surface tension and contact angle in the equation are strongly correlated; however, for the purpose of simplifying the equation, the surface tension parameter is no longer considered. Furthermore, since the emulsified asphalt is applied to the surface of the cement-stabilized crushed stone base course, the crack width, an index in the penetration kinetics equation, is... R d For cement-stabilized crushed stone, pore size is more appropriate. However, since the pore distribution of cement-stabilized crushed stone base is relatively random and not very uniform, porosity is used instead. P replace R d Furthermore, considering that the original equation analyzes the upward seepage of liquid from the lower surface through capillary action, which is opposite to the infiltration direction of emulsified asphalt sprayed on a cement-stabilized crushed stone base course, but considering that the corresponding influencing factors are applicable to emulsified asphalt, the corresponding influencing factors in this formula can be retained, while... P Place it on the molecule.

3. The method for predicting the penetration depth of emulsified asphalt tack coat according to claim 1, characterized in that: In step 1, according to Poiseuille's law, the formula for the liquid permeation rate, which represents the balance between viscous force, capillary action, and hydrostatic force, is: In the formula v =permeation rate, dh =Change in penetration depth, dt =Change in infiltration time, R d = Crack width, η =Dynamic viscosity, h =Penetration depth; Osmotic pressure difference In the formula σ =Surface tension: R d = Crack width, θ =Contact angle, ρ =Density, g = Gravitational acceleration; then Substituting the values ​​into the permeation rate, we obtain the classic Lucas-Washburn equation for liquid osmosis kinetics. In the formula r =particle size, t =Infiltration time; taken when capillary action and liquid gravity are equal in magnitude. =0, the liquid is in equilibrium, which is the maximum depth that the osmotic energy can reach: .

4. The method for predicting the penetration depth of emulsified asphalt tack coat according to claim 1, characterized in that: The specific steps for measuring the penetration depth of emulsified asphalt using the press destructive method are as follows: (1) Spray emulsified asphalt onto the surface of the cured water-stabilized crushed stone base course, let it stand for 3 days, and then cover the upper surface of the water-stabilized crushed stone specimen with a piece of paper; (2) Place the water-stabilized specimen on the press and press it at a rate of 2 mm / min until cracks appear on the surface of the specimen and it becomes loose, but avoid it from falling apart completely; (3) Divide the specimen longitudinally into four equal parts, and break apart the aggregate by hand according to the original structure of the specimen; (4) Take three pieces from each part, for a total of 12 pieces, and average the values ​​of the 12 pieces. Take the final average value as the final representative penetration depth.

5. The method for predicting the penetration depth of emulsified asphalt tack coat according to claim 1, characterized in that: In step 4, the water-stable specimen is slowly placed into the bucket, ensuring that water can only flow out through the top outlet. Then, it is left to stand. During this time, bubbles will continuously rise to the top, and the mass will decrease accordingly. This is because water replaces the air in the pores of the specimen opening. Water is then slowly added until no more bubbles rise and the mass on the electronic scale no longer changes after adding water. The mass at this point is recorded as M2.

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