A sponge city drainage asphalt pavement structure

Abstract

The application relates to the field of sponge city construction, and particularly discloses a drainage asphalt pavement structure of a sponge city, which comprises a pavement base layer located at the lowermost layer, an asphalt lower seal layer laid on the pavement base layer, an asphalt mixture structure layer laid on the asphalt lower seal layer, an asphalt upper seal layer laid on the asphalt mixture structure layer, and a drainage asphalt concrete paving layer laid on the asphalt upper seal layer, wherein the drainage asphalt concrete paving layer is formed by laying drainage asphalt mixture; the drainage asphalt mixture is composed of raw materials in the following proportions by weight: coarse aggregate 70-100 parts, fine aggregate 5-15 parts, mineral powder 2-6 parts, asphalt 3-7 parts and water stabilizer 4-8 parts. The drainage asphalt pavement structure has the advantages of water erosion resistance and long service life.

Description

Technical Field

[0001] The present application relates to the field of sponge city construction, and more specifically, to a drainage asphalt pavement structure for a sponge city. Background Art

[0002] Sponge city is a new generation of urban stormwater management concept. It means that the city can adapt to environmental changes and respond to natural disasters caused by rainwater like a sponge, with good flexibility. It absorbs, stores, infiltrates and purifies water when it rains, and releases and utilizes the stored water when needed, so as to realize the free migration of rainwater in the city.

[0003] Drainage asphalt pavement refers to a new type of asphalt concrete surface layer with a void ratio of about 20% after compaction, which can form drainage channels inside the mixture. Its essence is an open-graded asphalt mixture with a skeleton-void structure formed by single-size crushed stones according to the embedding mechanism.

[0004] Because drainage asphalt pavement needs to allow rainwater to penetrate and drain, the contact time between drainage asphalt concrete and rainwater is long, which causes rainwater to erode the drainage asphalt pavement for a long time, and then causes the strength of the drainage asphalt pavement to decrease. Summary of the Invention

[0005] In order to reduce the impact of long-term rainwater erosion on the strength of drainage asphalt pavement, this application provides a drainage asphalt pavement structure for sponge cities, which adopts the following technical solutions:

[0006] A drainage asphalt pavement structure for a sponge city comprises a pavement base layer at the lowest layer, an asphalt lower seal layer is laid on the pavement base layer, an asphalt mixture structural layer is laid on the asphalt lower seal layer, an asphalt upper seal layer is laid on the asphalt mixture structural layer, and a drainage asphalt concrete pavement layer is laid on the asphalt upper seal layer, wherein the drainage asphalt concrete pavement layer is paved with a drainage asphalt mixture; the drainage asphalt mixture is composed of the following raw materials in parts by weight: 70 to 100 parts of coarse aggregate, 5 to 15 parts of fine aggregate, 2 to 6 parts of mineral powder, 4 to 5 parts of asphalt, and 4 to 8 parts of water stabilizer, wherein the water stabilizer comprises a binder, a water repellent, and a curing accelerator, and the weight ratio of the binder, water repellent, and curing accelerator is 3 to 5:1 to 3:1.

[0007] By adopting the above technical solution, the bonding strength between asphalt and coarse aggregate and fine aggregate is improved by using adhesives, and the curing accelerator is used to promote the curing of adhesives and water repellents to reduce water infiltration. The water repellent further reduces water infiltration, so that water is discharged from the drainage asphalt mixture, thereby effectively reducing the damage to the drainage asphalt mixture caused by long-term retention of water, and further reducing the impact of long-term rainwater erosion on the strength of the drainage asphalt pavement.

[0008] Preferably, the coarse aggregate is graded from three specifications, including 16mm-13.2mm coarse aggregate, 13.2mm-9.5mm coarse aggregate and 9.5mm-4.75mm coarse aggregate, and the weight ratio of the three is 3:5:9.

[0009] By adopting the above technical solution and using three specifications of coarse aggregate gradation, the porosity of the drainage asphalt mixture meets the requirements of drainage asphalt pavement, so that rainwater and the like can be discharged through the drainage asphalt pavement.

[0010] Preferably, the coarse aggregate is a mixture of steel slag and limestone, the 16mm-13.2mm coarse aggregate is limestone, and the 13.2mm-9.5mm coarse aggregate and the 9.5mm-4.75mm coarse aggregate are steel slag.

[0011] By adopting the above technical solution, steel slag is used to replace part of the limestone aggregate. Since steel slag is a porous alkaline aggregate, it can effectively improve the connection strength between asphalt and coarse aggregate and effectively reduce the impact of moisture erosion on the strength of asphalt pavement.

[0012] Preferably, the adhesive comprises methyl methacrylate and N-vinyl formamide, and the weight ratio of the methyl methacrylate to N-vinyl formamide is 2 to 4:1.

[0013] By adopting the above technical solution, methyl methacrylate is used as the main adhesive component, and N-vinyl formamide is added to improve the connection strength between the adhesive and asphalt. The adhesive is used as a bridge to improve the connection strength between asphalt and coarse aggregate and fine aggregate, effectively reducing the separation of asphalt from coarse aggregate and fine aggregate due to water erosion, and reducing the impact of water erosion on asphalt pavement.

[0014] Preferably, the water repellent comprises sodium methyl siliconate and vinyl silicone oil, and the weight ratio of the two is 1:1.

[0015] By adopting the above technical solution, sodium methyl siliconate and vinyl silicone oil improve the penetration ability of the adhesive, so that the adhesive can penetrate into the gaps between coarse aggregate and fine aggregate, align and bond them, thereby effectively improving the bonding effect. After curing, sodium methyl siliconate is converted into methylsiloxane and vinyl silicone oil to improve the waterproof ability of the drainage asphalt pavement.

[0016] Preferably, the curing accelerator is iron sulfide modified medical stone.

[0017] By adopting the above technical solution, iron sulfide crystals are loaded on the surface of medical stone to act as a nucleating agent to promote the curing of the adhesive. When the adhesive is cured, the water repellent is simultaneously cured on the coarse aggregate and the fine aggregate, thereby improving the water erosion resistance of the drainage asphalt mixture.

[0018] Preferably, the curing accelerator is prepared by the following steps: placing medical stone in a sodium sulfide solution, stirring at 40-60° C. for 10-30 minutes, rotating at 60-100 r / min, taking out the medical stone, washing it, placing it in a carboxymethyl cellulose solution, and letting it stand for 5-10 minutes, then taking out the medical stone, adding the ferric sulfate solution dropwise onto the medical stone, and stirring and mixing at the same time, and after mixing, taking out the medical stone and letting it stand at 4-10° C. for 30-40 minutes to prepare the curing accelerator.

[0019] By adopting the above technical solution, iron sulfate and sodium sulfide generate iron sulfide crystals, and the iron sulfide crystals are combined with medical stone through hydroxymethyl cellulose to prepare a curing accelerator. After the asphalt is combined with the coarse aggregate and the fine aggregate through the adhesive, the curing accelerator combines with the asphalt on the one hand and promotes the curing of the adhesive on the other hand, effectively improving the bonding strength between the asphalt and the coarse aggregate and the fine aggregate, thereby reducing the impact of moisture erosion on the strength of the drainage asphalt pavement.

[0020] Preferably, the drainage asphalt mixture is prepared by the following steps: mixing coarse aggregate, fine aggregate and mineral powder, drying at 180-200°C for 10-20 minutes, adding adhesive, water repellent and curing accelerator and stirring for 3-5 minutes, and finally adding asphalt preheated to 140-160°C, stirring and mixing evenly, and keeping warm for 3-5 minutes to obtain the drainage asphalt mixture.

[0021] By adopting the above technical solution, drainage asphalt mixture can be prepared through simple mixing, the operation is simple, and the product is easy to obtain.

[0022] In summary, this application has the following beneficial effects:

[0023] 1. Since the adhesive is used to improve the bonding strength between asphalt and coarse aggregate and fine aggregate, the curing accelerator promotes the curing of the adhesive and water repellent to reduce water infiltration. The water repellent further reduces water infiltration, allowing water to be discharged from the drainage asphalt mixture, thereby effectively reducing the damage to the drainage asphalt mixture caused by long-term moisture retention, and further reducing the impact of long-term rainwater erosion on the strength of the drainage asphalt pavement.

[0024] 2. In this application, methyl methacrylate is preferably used as the main adhesive component, and N-vinyl formamide is added to improve the connection strength between the adhesive and asphalt. The adhesive is used as a bridge to improve the connection strength between asphalt and coarse aggregate and fine aggregate, effectively reducing the separation of asphalt from coarse aggregate and fine aggregate due to water erosion, and reducing the impact of water erosion on asphalt pavement.

[0025] 3. In this application, iron sulfide crystals are loaded on the surface of medical stone to act as a nucleating agent to promote the curing of the adhesive. When the adhesive is cured, the water repellent is simultaneously cured on the coarse aggregate and the fine aggregate, thereby improving the water erosion resistance of the drainage asphalt mixture. DETAILED DESCRIPTION

[0026] The coarse aggregate in this application includes limestone with a particle size of 16mm to 13.2mm, steel slag with a particle size of 13.2mm to 9.5mm, and steel slag with a particle size of 9.5mm to 4.75mm; the fine aggregate is limestone with a particle size of 4.75mm to 0; the mineral powder is S95 grade slag powder; the asphalt is SBS modified asphalt; methyl methacrylate and N-vinyl formamide are purchased from the market; the medical stone particle size is 2-3mm; the sodium sulfide solution concentration is 0.1mol / L; the carboxymethyl cellulose solution volume fraction is 1%, purchased from the market; the ferric sulfate solution concentration is 0.2mol / L;

[0027] The present application is further described in detail below with reference to the embodiments.

[0028] Preparation Example

[0029] Preparation Example 1

[0030] This preparation example discloses a curing accelerator, which is prepared by the following steps:

[0031] Place medical stone in sodium sulfide solution, with the sodium sulfide solution covering the medical stone, stir at 40°C for 10 minutes, with a rotation speed of 60r / min, take out the medical stone, wash it, and place it in carboxymethyl cellulose solution, let it stand for 5 minutes, then take out the medical stone, add ferric sulfate solution dropwise to the medical stone, and stir and mix at the same time. After mixing, take out the medical stone and let it stand at 4°C for 30 minutes to prepare a curing accelerator.

[0032] Preparation Example 2

[0033] Place medical stone in sodium sulfide solution, with the sodium sulfide solution covering the medical stone, stir at 50°C for 20 minutes, with a rotation speed of 80r / min, take out the medical stone, wash it, and place it in carboxymethyl cellulose solution, let it stand for 7 minutes, then take out the medical stone, add ferric sulfate solution dropwise to the medical stone, and stir and mix at the same time. After mixing, take out the medical stone and let it stand at 7°C for 35 minutes to prepare a curing accelerator.

[0034] Preparation Example 3

[0035] Place medical stone in sodium sulfide solution, the sodium sulfide solution covers the medical stone, stir at 60°C for 30 minutes, and rotate at 100r / min. Take out the medical stone, wash it, and place it in carboxymethyl cellulose solution, let it stand for 10 minutes. Then take out the medical stone, add ferric sulfate solution dropwise to the medical stone, and stir and mix at the same time. After mixing, take out the medical stone and let it stand at 10°C for 40 minutes to prepare a curing accelerator.

[0036] Example

[0037] Example 1

[0038] This embodiment discloses a sponge city drainage asphalt pavement structure, comprising a pavement base layer at the bottom layer, an asphalt lower seal layer paved on the upper surface of the pavement base layer, an asphalt mixture structural layer paved on the upper surface of the asphalt mixture structural layer, an asphalt upper seal layer paved on the upper surface of the asphalt mixture structural layer, and a drainage asphalt concrete pavement layer paved on the upper surface of the asphalt upper seal layer. Both the asphalt lower seal layer and the asphalt upper seal layer are paved with emulsified PC-2 asphalt. The asphalt mixture structural layer is paved with a densely distributed asphalt mixture. The drainage asphalt concrete pavement layer is paved with a drainage asphalt mixture.

[0039] Example 2

[0040] This embodiment discloses a drainage asphalt mixture, which is prepared by the following steps: 70 kg of coarse aggregate, 5 kg of fine aggregate and 2 kg of mineral powder are mixed, dried at 180° C. for 10 minutes, and then 2 kg of methyl methacrylate, 1 kg of N-vinyl formamide, 0.5 kg of sodium methyl siliconate, 0.5 kg of vinyl silicone oil and 1 kg of the curing accelerator prepared in Preparation Example 1 are added and stirred for 3 minutes. Finally, 3 kg of asphalt preheated to 150° C. is added, the mixture is stirred and mixed evenly, and the mixture is kept warm for 3 minutes to obtain the drainage asphalt mixture.

[0041] Example 3

[0042] This embodiment discloses a drainage asphalt mixture, which is prepared by the following steps: 85 kg of coarse aggregate, 10 kg of fine aggregate and 4 kg of mineral powder are mixed, dried at 190° C. for 15 minutes, and then 3 kg of methyl methacrylate, 1 kg of N-vinyl formamide, 1 kg of sodium methyl siliconate, 1 kg of vinyl silicone oil and 1 kg of the curing accelerator prepared in Preparation Example 2 are added and stirred for 4 minutes. Finally, 5 kg of asphalt preheated to 150° C. is added, the mixture is stirred and mixed evenly, and the mixture is kept warm for 4 minutes to obtain the drainage asphalt mixture.

[0043] Example 4

[0044] This embodiment discloses a drainage asphalt mixture, which is prepared by the following steps: 100 kg of coarse aggregate, 15 kg of fine aggregate and 6 kg of mineral powder are mixed, dried at 200° C. for 20 minutes, and then 4 kg of methyl methacrylate, 1 kg of N-vinyl formamide, 1.5 kg of sodium methyl siliconate, 1.5 kg of vinyl silicone oil and 1 kg of the curing accelerator prepared in Preparation Example 3 are added and stirred for 5 minutes. Finally, 7 kg of asphalt preheated to 150° C. is added, the mixture is stirred and mixed evenly, and the mixture is kept warm for 5 minutes to obtain the drainage asphalt mixture.

[0045] Comparative Example

[0046] Comparative Example 1

[0047] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no adhesive is added.

[0048] Comparative Example 2

[0049] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no water repellent is added.

[0050] Comparative Example 3

[0051] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no curing accelerator is added.

[0052] Comparative Example 4

[0053] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no adhesive and water repellent are added.

[0054] Comparative Example 5

[0055] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no adhesive and curing accelerator are added.

[0056] Comparative Example 6

[0057] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no water repellent and curing accelerator are added.

[0058] Comparative Example 7

[0059] This comparative example discloses a drainage asphalt mixture, which is different from Example 3 in that no adhesive, water repellent and curing accelerator are added.

[0060] Performance testing

[0061] According to JTG E20-2011 "Test Procedures for Asphalt and Asphalt Mixtures in Highway Engineering"

[0062] T0709-2011 Asphalt mixture Marshall stability test, test the Marshall stability of asphalt mixture under immersion.

[0063] T0719-2011 Asphalt mixture rutting test, tests the dynamic stability of asphalt mixture.

[0064] T0733 asphalt mixture Kentburgh dispersion test, test water immersion dispersion test.

[0065] JTG / T 3350-03—2020 Standard drainage method for permeability coefficient of asphalt mixture, test permeability coefficient.

[0066] Table 1 Performance test data table

[0067]

[0068] From Example 3, Comparative Example 1, Comparative Example 6, and Comparative Example 7 and Table 1, it can be seen that using methyl methacrylate as the main adhesive component and adding N-vinyl formamide at the same time improves the connection strength between the adhesive and asphalt, and using the adhesive as a bridge to improve the connection strength between asphalt and coarse aggregate and fine aggregate, effectively reduces the separation of asphalt from coarse aggregate and fine aggregate due to water erosion, and reduces the impact of water erosion on asphalt pavement.

[0069] From Example 3, Comparative Example 2, Comparative Example 5 and Comparative Example 7 and Table 1, it can be seen that sodium methyl siliconate and vinyl silicone oil improve the penetration ability of the adhesive, so that the adhesive penetrates into the gaps between the coarse aggregate and the fine aggregate, aligns and bonds them, thereby effectively improving the bonding effect. After curing, sodium methyl siliconate is converted into methylsiloxane and vinyl silicone oil to improve the waterproof ability of the drainage asphalt pavement.

[0070] From Example 3, Comparative Example 3, Comparative Example 4 and Comparative Example 7 and Table 1, it can be seen that iron sulfide crystals are loaded on the surface of medical stone to act as a nucleating agent to promote the curing of the adhesive. When the adhesive is cured, the water repellent is simultaneously cured on the coarse aggregate and the fine aggregate, thereby improving the water erosion resistance of the drainage asphalt mixture.

[0071] From Example 3, Comparative Example 1, Comparative Example 2, Comparative Example 3 and Comparative Example 7 and Table 1, it can be seen that the adhesive is used to improve the bonding strength between asphalt and coarse aggregate and fine aggregate, the curing accelerator promotes the curing of the adhesive and the water repellent to reduce moisture infiltration, and the water repellent further reduces moisture infiltration, so that moisture is discharged from the drainage asphalt mixture, thereby effectively reducing the damage to the drainage asphalt mixture caused by long-term moisture retention, and further reducing the impact of long-term rainwater erosion on the strength of the drainage asphalt pavement.

[0072] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.

Claims

1. A drainage asphalt pavement structure for a sponge city, characterized in that: The invention comprises a pavement base layer at the lowest layer, an asphalt lower seal layer is laid on the pavement base layer, an asphalt mixture structural layer is laid on the asphalt lower seal layer, an asphalt upper seal layer is laid on the asphalt mixture structural layer, and a drainage asphalt concrete pavement layer is laid on the asphalt upper seal layer, wherein the drainage asphalt concrete pavement layer is paved with drainage asphalt mixture; the drainage asphalt mixture is composed of the following raw materials in parts by weight: 70 to 100 parts of coarse aggregate, 5 to 15 parts of fine aggregate, 2 to 6 parts of mineral powder, 4 to 5 parts of asphalt, and 4 to 8 parts of water stabilizer; the water stabilizer comprises an adhesive, a water repellent and a curing accelerator, and the weight ratio of the adhesive, the water repellent and the curing accelerator is 3 to 5:1 to 3:1; the curing accelerator is iron sulfide modified medical stone.

2. The drainage asphalt pavement structure for sponge cities according to claim 1, characterized in that: The coarse aggregate is graded from three specifications, including 16mm-13.2mm coarse aggregate, 13.2mm-9.5mm coarse aggregate and 9.5mm-4.75mm coarse aggregate, and the weight ratio of the three is 3:5:

9.

3. The drainage asphalt pavement structure for sponge cities according to claim 2 is characterized by: The coarse aggregate is a mixture of steel slag and limestone, the 16mm-13.2mm aggregate is limestone, and the 13.2mm-9.5mm coarse aggregate and the 9.5mm-4.75mm coarse aggregate are steel slag.

4. The drainage asphalt pavement structure for sponge cities according to claim 1, characterized in that: The adhesive comprises methyl methacrylate and N-vinyl formamide, and the weight ratio of the methyl methacrylate to the N-vinyl formamide is 2 to 4:

1.

5. The drainage asphalt pavement structure for sponge cities according to claim 1 is characterized by: The water repellent comprises sodium methyl siliconate and vinyl silicone oil, and the weight ratio of the two is 1:

1.

6. The drainage asphalt pavement structure for sponge cities according to claim 1, characterized in that: The curing accelerator is prepared by the following steps: placing medical stone in a sodium sulfide solution, stirring at 40-60 DEG C for 10-30 minutes, rotating at 60-100 r / min, taking out the medical stone, washing it, placing it in a carboxymethyl cellulose solution, and letting it stand for 5-10 minutes, then taking out the medical stone, dripping the ferric sulfate solution onto the medical stone, and stirring and mixing at the same time, taking out the medical stone after mixing, and letting it stand at 4-10 DEG C for 30-40 minutes to prepare the curing accelerator.

7. The drainage asphalt pavement structure for sponge cities according to claim 1, characterized in that: The drainage asphalt mixture is prepared by the following steps: mixing coarse aggregate, fine aggregate and mineral powder, drying at 180-200° C. for 10-20 minutes, adding adhesive, water repellent and curing accelerator and stirring for 3-5 minutes, and finally adding asphalt preheated to 140-160° C., stirring and mixing evenly, and keeping warm for 3-5 minutes to obtain the drainage asphalt mixture.

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