Asphalt special for airfield pavement and preparation method thereof

Abstract

The invention provides special asphalt for an airport pavement. The special asphalt is prepared from the following raw materials in parts by weight: 85-100 parts of matrix asphalt; 1-3 parts by weight of naphthenic oil; 2.5 parts by weight to 3.5 parts by weight of a modifier; 2.5 to 3 parts by weight of ethylene propylene diene monomer; and 0.2 to 0.4 part by weight of a silane coupling agent. Compared with the prior art, the special asphalt for the airfield pavement provided by the invention adopts the components with specific contents, realizes relatively good overall interaction, has relatively good high-temperature performance and low-temperature performance, can resist deformation and cracking under a high-stress condition, has relatively strong anti-aging performance, and improves the performance of the asphalt pavement.

Description

Technical Field

[0001] The invention relates to the technical field of airport pavement materials, and more specifically, to a special asphalt for airport pavement and a preparation method thereof. Background Art

[0002] Asphalt pavement has the characteristics of smooth surface, no joints, low noise, short construction period, and fast traffic opening. It occupies a major position in the asphalt of civil airport pavement. When the aircraft lands, it will generate a large vertical impact force, which puts high requirements on the strength and toughness of the runway surface, and can resist deformation and cracking under high stress conditions. When the aircraft lands and slows down, the pilot may activate the engine's reverse thrust device; part of the engine exhaust originally discharged forward will be directed to the front to help the aircraft slow down. This process will produce high-temperature airflow to erode the asphalt pavement, causing thermal aging of the asphalt pavement. The friction between the brake discs during the deceleration process of the aircraft after landing will cause the tires and the asphalt pavement to generate a lot of heat, causing thermal aging of the asphalt pavement. In areas with extremely strong solar radiation, the ultraviolet rays in the sunlight can cause photo-oxidation on the asphalt surface, resulting in discoloration, hardening, cracking and other phenomena on the asphalt surface. After the asphalt pavement ages, its durability deteriorates, and problems such as looseness, aging and cracks appear. If not handled in time, it may affect the safety of aircraft takeoff and landing. Therefore, it is necessary to develop a special asphalt for airports to improve the performance of asphalt and reduce the occurrence of airport pavement diseases.

[0003] At present, the types of asphalt used for airport pavements include epoxy asphalt, rubber-modified asphalt, high modulus asphalt, and SBS-modified asphalt. As a new type of material, epoxy asphalt has good durability, but its price is high and its cost is high. Rubber-modified asphalt has good fatigue resistance, but its low-temperature performance is poor, and its use is limited in cold areas. High modulus asphalt has good rutting resistance, but its low-temperature performance is poor, its cost is high, and there may be supply chain challenges, which limit its application in large-scale airport pavement projects. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a special asphalt for airport pavement and a preparation method thereof. The special asphalt for airport pavement provided by the present invention has good high temperature performance and low temperature performance, can resist deformation and cracking under high stress conditions, has strong anti-aging performance, and improves the performance of asphalt pavement.

[0005] The present invention provides a special asphalt for airport pavement, which is prepared from raw materials including the following components:

[0006] 85 to 100 parts by weight of base asphalt;

[0007] 1 to 3 parts by weight of naphthenic oil;

[0008] 2.5 to 3.5 parts by weight of modifier;

[0009] 2.5 to 3 parts by weight of EPDM rubber;

[0010] Silane coupling agent: 0.2 to 0.4 parts by weight.

[0011] Preferably, the C / H atomic ratio of the matrix asphalt is 0.5-1.0, the residual penetration ratio is not less than 65%, the colloid instability index is not greater than 0.45, the 25°C penetration is 63-75 dmm, and the weight-average molecular weight is 1400-2200 g / mol.

[0012] Preferably, the cycloparaffinic oil contains 80% to 90% cycloparaffins, 5% to 10% alkylcycloparaffins, and less than 5% aliphatic paraffins.

[0013] Preferably, the flash point of the cycloparaffinic oil is ≥ 200°C.

[0014] Preferably, the modifier is a styrene-butadiene-styrene block copolymer with a molecular weight of 100,000 to 150,000.

[0015] Preferably, the silane coupling agent is morpholinopropyltrimethoxysilane.

[0016] The present invention also provides a method for preparing the special asphalt for airport pavement described in the above technical solution, comprising the following steps:

[0017] The base asphalt, cyclohexane oil, modifier and EPDM rubber are mixed, swelled and sheared in sequence, and then a silane coupling agent is added for development to obtain special asphalt for airport pavement.

[0018] Preferably, the swelling temperature is 170° C. to 185° C., and the swelling time is 40 min to 60 min.

[0019] Preferably, the shearing temperature is 180° C. to 185° C., the rotation speed is 4000 r / min to 5000 r / min, and the time is 50 min to 60 min.

[0020] Preferably, the growth temperature is 175°C to 185°C, and the growth time is 120 min to 150 min.

[0021] The invention provides a special asphalt for airport pavement, which is prepared from raw materials including the following components: 85 to 100 parts by weight of base asphalt; 1 to 3 parts by weight of naphthenic oil; 2.5 to 3.5 parts by weight of modifier; 2.5 to 3 parts by weight of EPDM rubber; and 0.2 to 0.4 parts by weight of silane coupling agent. Compared with the prior art, the special asphalt for airport pavement provided by the invention adopts specific content components to achieve better overall interaction, and the product has better high temperature performance and low temperature performance, can resist deformation and cracking under high stress conditions, has strong anti-aging performance, and improves the performance of asphalt pavement.

[0022] In addition, the preparation method provided by the present invention has simple process, mild and easy-to-control conditions, and readily available raw materials with low cost, and has broad application prospects in airport asphalt. DETAILED DESCRIPTION

[0023] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] The present invention provides a special asphalt for airport pavement, which is prepared from raw materials including the following components:

[0025] 85 to 100 parts by weight of base asphalt;

[0026] 1 to 3 parts by weight of naphthenic oil;

[0027] 2.5 to 3.5 parts by weight of modifier;

[0028] 2.5 to 3 parts by weight of EPDM rubber;

[0029] Silane coupling agent: 0.2 to 0.4 parts by weight.

[0030] In the present invention, the special asphalt for airport pavement is prepared from raw materials including base asphalt, cyclohexane oil, modifier, EPDM rubber and silane coupling agent, preferably prepared from base asphalt, cyclohexane oil, modifier, EPDM rubber and silane coupling agent.

[0031] In the present invention, the C / H atomic ratio of the matrix asphalt is preferably 0.5 to 1.0, the residual penetration ratio is preferably not less than 65%, the colloid instability index is preferably not more than 0.45, the 25°C penetration is preferably 63 to 75 dmm, and the weight average molecular weight is preferably 1400 to 2200 g / mol. The present invention has no particular restrictions on the source of the matrix asphalt, and commercially available products known to those skilled in the art can be used.

[0032] In the present invention, the special asphalt for airport pavement includes 85 to 100 parts by weight of base asphalt, preferably 100 parts by weight.

[0033] In the present invention, the cycloalkanes in the cycloalkanes are preferably 80% to 90%, the alkylcycloalkanes are preferably 5% to 10%, and the aliphatic alkanes are preferably <5%; the flash point of the cycloalkanes is preferably ≥ 200°C. The present invention optimizes the auxiliary material components, which can improve the storage stability of airport pavement asphalt and reduce the unstable product quality caused by the fluctuation of the auxiliary material components. The present invention has no special restrictions on the source of the cycloalkanes, and commercial products known to those skilled in the art can be used.

[0034] In the present invention, the special asphalt for airport pavement includes 1 to 3 parts by weight of cyclohexane oil, preferably 2 parts by weight.

[0035] In the present invention, the modifier is preferably a styrene-butadiene-styrene block copolymer (SBS), the SBS is preferably a linear SBS, and the molecular weight is preferably 100,000 to 150,000. In a preferred embodiment of the present invention, the modifier is a polymer modifier 791H. The present invention has no special restrictions on the source of the modifier, and commercially available products known to those skilled in the art can be used.

[0036] In the present invention, the special asphalt for airport pavement includes 2.5 to 3.5 parts by weight of a modifier, preferably 3.5 parts by weight.

[0037] In the present invention, the ethylene propylene diene monomer (EPDM) has good compatibility with asphalt, and a spatial network structure with good compatibility and high stability is easily formed during the modification process, so that the prepared special asphalt for airport pavement has good strength and toughness, and can resist deformation and cracking under high stress conditions, and improve the light aging and heat aging properties of the material. The present invention has no special restrictions on the source of the ethylene propylene diene monomer, and commercially available products known to those skilled in the art can be used.

[0038] In the present invention, the special asphalt for airport pavement includes 2.5 to 3 parts by weight of EPDM rubber, preferably 3 parts by weight.

[0039] In the present invention, the silane coupling agent is preferably morpholinopropyltrimethoxysilane, which mainly acts as a stabilizer. The present invention has no special restrictions on the source of the silane coupling agent, and commercially available products known to those skilled in the art can be used.

[0040] In the present invention, the special asphalt for airport pavement includes 0.2 to 0.4 parts by weight of silane coupling agent, preferably 0.25 parts by weight.

[0041] The special asphalt for airport pavement provided by the present invention adopts components with specific contents to achieve better overall interaction. The product has good high-temperature performance and low-temperature performance, can resist deformation and cracking under high-stress conditions, has strong anti-aging performance, and improves the performance of asphalt pavement.

[0042] The present invention also provides a method for preparing the special asphalt for airport pavement described in the above technical solution, comprising the following steps:

[0043] The base asphalt, cyclohexane oil, modifier and EPDM rubber are mixed, swelled and sheared in sequence, and then a silane coupling agent is added for development to obtain special asphalt for airport pavement.

[0044] In the present invention, the base asphalt, cyclohexane oil, modifier, EPDM rubber and silane coupling agent are the same as those in the above technical solution, and will not be described in detail here.

[0045] In the present invention, the swelling temperature is preferably 170° C. to 185° C., more preferably 185° C., and the swelling time is preferably 40 min to 60 min, more preferably 50 min.

[0046] In the present invention, the swollen asphalt is sheared; the shearing temperature is preferably 180°C to 185°C, more preferably 180°C, the rotation speed is preferably 4000r / min to 5000r / min, more preferably 4500r / min, and the time is preferably 50min to 60min, more preferably 60min.

[0047] In the present invention, a silane coupling agent is added to the sheared asphalt for development; the development temperature is preferably 175°C to 185°C, more preferably 185°C, and the development time is preferably 120min to 150min, more preferably 120min.

[0048] The preparation method provided by the present invention only requires swelling, shearing and developing the raw materials to obtain the product. The preparation process is simple, the conditions are mild and easy to control, and the raw materials are easily available and low in cost. The obtained product has good storage stability, the compatibility of the modifier with asphalt is excellent, and it can resist deformation and cracking under high stress conditions, improve the light aging and heat aging properties of the material, and has broad application prospects in airport asphalt.

[0049] The present invention provides a special asphalt for airport pavement and a preparation method thereof, which has the following beneficial effects:

[0050] (1) The present invention optimizes the microscopic components of the base asphalt, selects the base asphalt with the appropriate components, and improves the compatibility between the asphalt and the modifier; optimizes the molecular weight and the residual penetration ratio of the base asphalt, and improves the anti-aging performance of the modified asphalt.

[0051] (2) The present invention optimizes the cycloparaffinic oil component to improve the storage stability of airport pavement asphalt and reduce product instability caused by fluctuations in raw material components.

[0052] (3) The specific modifier used in the present invention improves the strength and toughness of airport pavement asphalt, can resist deformation and cracking under high stress conditions, and improves the light aging and heat aging properties of the material.

[0053] (4) The modifier used in the present invention is cheap, which reduces the cost of asphalt materials for airport pavement.

[0054] The invention provides a special asphalt for airport pavement, which is prepared from raw materials including the following components: 85 to 100 parts by weight of base asphalt; 1 to 3 parts by weight of naphthenic oil; 2.5 to 3.5 parts by weight of modifier; 2.5 to 3 parts by weight of EPDM rubber; and 0.2 to 0.4 parts by weight of silane coupling agent. Compared with the prior art, the special asphalt for airport pavement provided by the invention adopts specific content components to achieve better overall interaction, and the product has better high temperature performance and low temperature performance, can resist deformation and cracking under high stress conditions, has strong anti-aging performance, and improves the performance of asphalt pavement.

[0055] In addition, the preparation method provided by the present invention has simple process, mild and easy-to-control conditions, and readily available raw materials with low cost, and has broad application prospects in airport asphalt.

[0056] In order to further illustrate the present invention, the following examples are used to explain it in detail. The raw materials used in the following examples of the present invention are all commercially available products; among them, the various indicators of the base asphalt are shown in the following Table 1.

[0057] Table 1 Key index data of matrix asphalt

[0058] Test items Base asphalt 1 Base Asphalt 2 Base Asphalt 3 Test methods Needle penetration (25℃, 100g, 5s) / 0.1mm 68 69 68 T 0604 Residual penetration ratio / % 64 69 68 T 0605 Colloid instability index 0.4 0.55 0.4 T 0606 Asphalt C / H atomic ratio / % 0.8 0.76 0.75 / <![CDATA[Asphalt weight-average molecular weight / g·mol -1 > 1940 2030 2200 /

[0059] The various indicators of cyclohexane oil are shown in Table 2 below.

[0060] Table 2 Key indicators of naphthenic oil

[0061] Test items Naphthenic oil 1 Naphthenic oil 2 Naphthenic oil 3 Test methods Flash point / ℃ 230 200 232 T 0611 Cycloalkanes / % 70.3 88.0 89.2 / Hydrocarbyl cycloalkanes / % 25.1 8.3 7.5 / Aliphatic alkanes / % 4.6 3.7 3.3 /

[0062] The above method for detecting the C / H atomic ratio of asphalt adopts an elemental analyzer to determine the C / H atomic ratio, and an organic element analyzer (EA test) uses an elemental analyzer to determine its carbon and hydrogen content, thereby obtaining the C / H mass ratio; the weight-average molecular weight of asphalt is detected by gel permeation chromatography (GPC); the detection method of cycloalkanes adopts gas chromatography-mass spectrometry (GC-MS) method.

[0063] Comparative Example 1

[0064] Matrix asphalt 1# (indicators see Table 1), 500g of the asphalt was added with modifier 791H SBS17.5g, EPDM15g, and cyclohexane oil 3# (indicators see Table 2) 10g for swelling, the swelling temperature was 185°C, the swelling time was 50min, the temperature was controlled at 180°C using a direct heating jacket, the rotation speed was 4500r / min, and the shearing was performed for 60min. After the shearing was completed, the obtained sample was transferred to a temperature-controlled heating jacket, 1.25g of a silane coupling agent (morpholinopropyltrimethoxysilane) was added, the temperature was controlled at 185°C, and the stirring was performed for 120min to obtain an airport pavement asphalt product.

[0065] Comparative Example 2

[0066] Matrix asphalt 2# (indicators see Table 1), 500g of the asphalt was added with modifier 791H SBS17.5g, EPDM15g, and cyclohexane oil 3# (indicators see Table 2) 10g for swelling, the swelling temperature was 185°C, the swelling time was 50min, the temperature was controlled at 180°C using a direct heating jacket, the rotation speed was 4500r / min, and the shearing was performed for 60min. After the shearing was completed, the obtained sample was transferred to a temperature-controlled heating jacket, 1.25g of a silane coupling agent (morpholinopropyltrimethoxysilane) was added, the temperature was controlled at 185°C, and the stirring was performed for 120min to obtain an airport pavement asphalt product.

[0067] Comparative Example 3

[0068] Matrix asphalt 3# (indicators see Table 1), 500g of the asphalt was added with modifier 791H SBS17.5g, EPDM 15g, and cyclohexane oil 1# (indicators see Table 2) 10g for swelling, the swelling temperature was 185°C, the swelling time was 50min, the temperature was controlled at 180°C using a direct heating jacket, the rotation speed was 4500r / min, and the shearing was performed for 60min. After the shearing was completed, the obtained sample was transferred to a temperature-controlled heating jacket, 1.25g of a silane coupling agent (morpholinopropyltrimethoxysilane) was added, the temperature was controlled at 185°C, and the stirring was performed for 120min to obtain an airport pavement asphalt product.

[0069] Comparative Example 4

[0070] Matrix asphalt 3# (indicators see Table 1), 500g of the asphalt was added with modifier 791H SBS17.5g, EPDM 15g, and cyclohexane oil 2# (indicators see Table 2) 10g for swelling, the swelling temperature was 185°C, the swelling time was 50min, the temperature was controlled at 180°C using a direct heating jacket, the rotation speed was 4500r / min, and the shearing was performed for 60min. After the shearing was completed, the obtained sample was transferred to a temperature-controlled heating jacket, 1.25g of a silane coupling agent (morpholinopropyltrimethoxysilane) was added, the temperature was controlled at 185°C, and the stirring was performed for 120min to obtain an airport pavement asphalt product.

[0071] Example 1

[0072] Matrix asphalt 3# (indicators see Table 1), 500g of the asphalt was added with modifier 791H SBS17.5g, EPDM 15g, and cyclohexane oil 3# (indicators see Table 2) 10g for swelling, the swelling temperature was 185°C, the swelling time was 50min, the temperature was controlled at 180°C using a direct heating jacket, the rotation speed was 4500r / min, and the shearing was performed for 60min. After the shearing was completed, the obtained sample was transferred to a temperature-controlled heating jacket, 1.25g of a silane coupling agent (morpholinopropyltrimethoxysilane) was added, the temperature was controlled at 185°C, and the stirring was performed for 120min to obtain an airport pavement asphalt product.

[0073] The various properties of the asphalt products used in the pavement of each airport were tested, and the results are shown in Tables 3 to 4 below.

[0074] Table 3 Basic performance index data of products

[0075]

[0076] Table 4 Product road performance data

[0077] Test items Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Example 1 Test methods Marshall stability / N 8.3 8.6 8.5 9.0 15.2 T 0604 Dynamic stability / times / mm 2312 2400 2514 2300 5150 T 0605 Bending failure strain / μ∈ 2804 2903 2800 2812 3538 T 0606

[0078] It can be seen from the above table: through the modified asphalt indicators of Table 3 Comparative Examples 1 to 4 and Example 1, Example 1 is compared with Comparative Examples 1 and Comparative Examples 4, and the airport asphalt aging extension index is 6cm higher, and the ultraviolet aging extension ratio is 9% higher. Compared with Comparative Examples 2 and Comparative Examples 3, Example 1 and Comparative Examples 2 and 3 have poor segregation indicators; through the pavement performance indicators of Table 4 Comparative Examples 1 to 4 and Example 1, Example 1 has a higher Marshall stability, indicating that the asphalt mixture has a strong destructive strength and resistance to plastic flow under high temperature conditions, a higher dynamic stability index, indicating that the asphalt mixture has a strong resistance to rutting under high temperature conditions, and a better bending failure strain index, indicating that the asphalt mixture has a strong resistance to cracking at low temperatures. In summary, through the optimization of the components of raw and auxiliary materials, and the corresponding adjustment of the preparation method, the special asphalt for airport pavement provided by the present invention has a higher destructive strength, better resistance to rutting, and low temperature resistance to cracking.

[0079] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A special asphalt for airport pavement, prepared from raw materials including the following components: 85 to 100 parts by weight of base asphalt; 1 to 3 parts by weight of naphthenic oil; 2.5 to 3.5 parts by weight of modifier; 2.5 to 3 parts by weight of EPDM rubber; Silane coupling agent: 0.2 to 0.4 parts by weight.

2. The special asphalt for airport pavement according to claim 1, characterized in that: The C / H atomic ratio of the matrix asphalt is 0.5-1.0, the residual penetration ratio is not less than 65%, the colloid instability index is not greater than 0.45, the 25°C penetration is 63-75 dmm, and the weight-average molecular weight is 1400-2200 g / mol.

3. The special asphalt for airport pavement according to claim 1, characterized in that: The naphthenic oil contains 80% to 90% cycloalkanes, 5% to 10% hydrocarbon cycloalkanes, and less than 5% aliphatic alkanes.

4. The special asphalt for airport pavement according to claim 1, characterized in that: The flash point of the cycloparaffinic oil is ≥200°C.

5. The special asphalt for airport pavement according to claim 1, characterized in that: The modifier is a styrene-butadiene-styrene block copolymer with a molecular weight of 100,000 to 150,000.

6. The special asphalt for airport pavement according to claim 1, characterized in that: The silane coupling agent is morpholinopropyltrimethoxysilane.

7. A method for preparing the special asphalt for airport pavement according to any one of claims 1 to 6, comprising the following steps: The base asphalt, cyclohexane oil, modifier and EPDM rubber are mixed, swelled and sheared in sequence, and then a silane coupling agent is added for development to obtain special asphalt for airport pavement.

8. The preparation method according to claim 7, characterized in that: The swelling temperature is 170° C. to 185° C., and the swelling time is 40 min to 60 min.

9. The preparation method according to claim 7, characterized in that: The shearing temperature is 180° C. to 185° C., the rotation speed is 4000 r / min to 5000 r / min, and the time is 50 min to 60 min.

10. The preparation method according to claim 7, characterized in that: The temperature of the development is 175° C. to 185° C., and the time is 120 min to 150 min.

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