Emulsified asphalt powder fiber thin slurry mixture penetration type pavement and construction process

Abstract

The present application relates to a kind of emulsified asphalt glue powder fiber thin slurry mixture penetration type pavement and construction process, every 1000m 2 The pavement is prepared according to the following volume of raw materials: first time 0.3m 3 ~0.6m 3 Sprinkle asphalt, 10m 3 ~50m 3 Sprinkle gravel, 0.3m 3 ~0.6m 3 Second time sprinkle asphalt, emulsified asphalt glue powder fiber thin slurry mixture is penetration material, 10m 3 ~40m 3 . Construction process is: first, sprinkle / sprinkle hot asphalt and equal-thickness particle size gravel in turn, then stabilize gravel, then sprinkle emulsified asphalt, then mix, paving and penetrate emulsified asphalt glue powder fiber thin slurry mixture, then vacuum water absorption, rolling, and emulsified asphalt glue powder fiber thin slurry mixture penetration type pavement is formed.The present application greatly improves crack resistance on the premise of ensuring the anti-rutting performance of asphalt pavement; on the other hand, it reduces the serious dependence of emulsified asphalt thin slurry mixture construction on high-temperature fine weather, and shortens the opening time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of road engineering, in particular to an emulsified asphalt, cement powder and fiber thin slurry mixture penetration type pavement and construction process. BACKGROUND

[0002] The semi-rigid base asphalt pavement structure layer combination, especially the "strong base thin surface type" semi-rigid base asphalt pavement structure layer combination has been widely used in China due to low cost and large bearing capacity, and has made great contribution to highway construction, and will be used more and more.

[0003] For a long time, the semi-rigid base thickness of the "strong base thin surface type" semi-rigid base asphalt pavement structure layer combination used in China is generally more than 50 cm, and the asphalt pavement thickness is generally about 12 cm. In theory, the design service life of such structure layer combination can reach more than 40 years, but engineering practice shows that most of them will be structurally damaged within 10 years. One of the main reasons is that the asphalt pavement is prone to early diseases such as rutting and cracking, and induces secondary diseases such as water damage. Therefore, it is imperative to further improve the anti-rutting performance and crack resistance of the asphalt pavement, especially the crack resistance.

[0004] At present, in order to solve the anti-rutting performance of the asphalt pavement, an emulsified asphalt thin slurry mixture penetration type pavement has been invented, which uses a large amount of fine aggregate, especially mineral powder, in the aggregate, and the powder-binder ratio (weight ratio of mineral powder to asphalt) is large, and the pavement has poor crack resistance. In addition, the construction of emulsified asphalt thin slurry mixture is heavily dependent on high temperature and fine weather, and generally requires construction in fine weather with a temperature not lower than 15℃. Even so, the forming time of emulsified asphalt thin slurry mixture with a paving thickness of more than 2 cm often needs several days, and the traffic opening time is too long. SUMMARY

[0005] The purpose of the present application is to provide an emulsified asphalt, cement powder and fiber thin slurry mixture penetration type pavement and construction process, which on the one hand greatly improves the crack resistance under the premise of ensuring the anti-rutting performance of the asphalt pavement, and on the other hand reduces the heavy dependence of emulsified asphalt thin slurry mixture construction on high temperature and fine weather, and shortens the traffic opening time.

[0006] To achieve the above purpose, the technical scheme adopted by the present application is:

[0007] An emulsified asphalt, cement powder and fiber thin slurry mixture penetration type pavement, wherein 1000 m 2 of the pavement is prepared according to the following volume of raw materials: 0.3 m 3 ~ 0.6 m 3 of first asphalt spraying, 10 m 3 ~ 50 m 3, the second time 0.3m 3 ~ 0.6m 3 , the emulsified asphalt glue powder fiber thin slurry mixture is the penetration material, and the volume is 10m 3 ~ 40m 3 .

[0008] Further, the first time the asphalt is hot rubber asphalt.

[0009] Further, the maximum particle size of the spreaded gravel is equal to the thickness of the pavement, and the content of the maximum particle size gravel is greater than or equal to 50%; the volume of the spreaded gravel is the bulk volume.

[0010] Because a large amount of the spreaded gravel has a maximum particle size equal to the thickness of the pavement, a "top" skeleton is formed in the pavement, which limits the plastic deformation of the pavement, so that the rutting does not occur. Such a maximum particle size gravel is called an equal-thickness particle size gravel, and the pavement made of a large amount of the equal-thickness particle size gravel is called an equal-thickness particle size asphalt pavement.

[0011] Further, the second time the asphalt is a cationic slow cracking and fast setting type SBR modified emulsified asphalt, the evaporation residue of which is called SBR modified asphalt, and the content is 60%.

[0012] Further, the emulsified asphalt glue powder fiber thin slurry mixture is prepared from the following raw materials in parts by weight: emulsified asphalt 10-20 parts, glue powder 30-40 parts, fiber 0.4-0.8 parts, and cement 0-5 parts.

[0013] Further, the emulsified asphalt is a cationic slow cracking and fast setting type SBR modified emulsified asphalt.

[0014] Further, the glue powder is waste tire rubber powder, and the particle size is 10-30 mesh.

[0015] Further, the fiber is one or more of glass fiber, polypropylene fiber, polyester fiber, lignin fiber, and mineral fiber, and the fiber length is 2-3 cm.

[0016] Further, the cement is fast-hardening Portland cement, and the strength grade is 32.5.

[0017] The role of the cement is mainly to adjust the workability of the emulsified asphalt glue powder fiber thin slurry mixture, so that it remains uniform, does not secrete water, and does not separate during construction, and the consistency is 2-3 cm (an index representing fluidity and penetration), and the emulsified asphalt glue powder fiber thin slurry mixture with such construction performance is described as having good workability. In addition, the roles are: one is to adjust the demulsification time of the emulsified asphalt waste tire rubber powder fiber thin slurry mixture; and two is to form a networked hardened cement structure in the pavement, to improve the crack resistance and rutting resistance of the pavement.

[0018] Cement is not necessary, only when it is needed to adjust the workability of emulsified asphalt fiber cement powder thin slurry mixture or / and adjust the demulsification time of emulsified asphalt waste tire rubber fiber thin slurry mixture.

[0019] Further, the specifications and quality of the used materials meet the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement”.

[0020] The present application mixes emulsified asphalt, rubber powder, fiber and cement according to the selected weight ratio of emulsified asphalt: rubber powder: fiber, and determines the cement dosage according to the workability, and then obtains the weight ratio of emulsified asphalt: rubber powder: fiber: cement. Research shows that when the weight ratio of emulsified asphalt to rubber powder is 1:3-1:2, the crack resistance of asphalt pavement is excellent, i.e. no temperature shrinkage cracks occur in the early and middle stages of the design service life, and even if a small amount of temperature shrinkage cracks occur in the later stage, they can be easily self-healed after temperature rise.

[0021] An emulsified asphalt rubber fiber thin slurry mixture penetration type pavement construction process, comprising the following steps:

[0022] I) First asphalt spreading

[0023] According to the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement”;

[0024] II) Spreading of gravel

[0025] According to the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement”;

[0026] III) Stable gravel

[0027] According to the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement”;

[0028] IV) Second asphalt spreading

[0029] According to the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement”;

[0030] V) Emulsified asphalt rubber fiber thin slurry mixture mixing, paving and penetration

[0031] The emulsified asphalt rubber fiber thin slurry mixture mixing, paving and penetration are performed according to the requirements of (JTG F40-2004) “Technical Specification for Construction of Highway Asphalt Pavement” and (CJJ 66-95) “Construction Specification for Pavement Thin Slurry Seal”;

[0032] VI) Vacuum water absorption

[0033] The vacuum water absorption is performed after the emulsified asphalt is demulsified;

[0034] Referring to (T 0658-1993) "Emulsified asphalt demulsification speed test", the judgment method of emulsified asphalt demulsification is that after emulsified asphalt fiber cement powder thin slurry mixture is paved, penetrated and completed, every 5 minutes, a water absorption white paper is pressed on the road surface, the position of each pressing is not repeated, when no brown spots are seen on the white paper, the emulsified asphalt has been demulsified;

[0035] The vacuum water absorption equipment includes a vacuum water absorption cloth, a vacuum water absorption pad, a vacuum water absorption pipe and a vacuum pump; the vacuum water absorption cloth is laid on the emulsified asphalt fiber cement powder thin slurry mixture, the vacuum water absorption pad is laid on the vacuum water absorption cloth, and the vacuum water absorption pad is connected with the vacuum pump through the vacuum water absorption pipe;

[0036] The vacuum water absorption process is that the vacuum pump is started, the vacuum degree in the road surface is gradually increased, water is absorbed out, when the water absorption is normal, the vacuum degree is controlled at 0.08 MPa, when the water cannot be absorbed out, the vacuum degree is gradually increased to absorb water, until the vacuum degree is increased to 0.13 MPa, when the water cannot be absorbed out for 2 minutes, the water absorption is ended;

[0037] Seven) rolling

[0038] The emulsified asphalt fiber cement powder thin slurry mixture penetration type road surface is formed by rolling 4-5 times by using a 16t rubber wheel roller, further extruding water and compacting the gap filler.

[0039] Compared with the prior art, the present application has the following beneficial effects:

[0040] 1. Compared with the prior art, the crack resistance of the present application is greatly improved

[0041] In the asphalt pavement, the crack resistance is highly related to the powder-gum ratio, the crack resistance is poor when the powder-gum ratio is large, and the crack resistance is good when the powder-gum ratio is small.

[0042] In the prior art, a large amount of mineral powder is used in the emulsified asphalt thin slurry mixture; and the present application does not use stone, and the powder-gum ratio is zero.

[0043] The low-temperature shrinkage is caused by the gap filler between the macadam, and the gap filler in the application is a mixture of SBR modified asphalt, rubber powder and fiber, and there is also a reticular hardened cement therein, and the crack resistance is greatly improved compared with the prior art. Through research, the reasons are: first, the powder-binder ratio is zero, and the stiffness modulus of the filler is greatly reduced. On the one hand, the low stiffness modulus filler is not easy to crack, and on the other hand, the low stiffness modulus filler is easy to self-heal after temperature rise even if cracks occur; second, the rubber powder is a non-temperature sensitive material, and the modulus of the rubber powder is much lower than that of the asphalt at low temperature. The rubber powder and the asphalt are not synchronized, the asphalt produces cracks (the initial state of the road surface crack), and the stress field of the rubber powder particles changes, which is easy to deflect the asphalt crack, induce a large number of crazing around the rubber powder particles (i.e. the end of the crack), and consume a large amount of cracking energy. A large amount of rubber powder particles will block the asphalt crack, and the asphalt crack will not develop into a through, long and wide road surface crack, and the asphalt crack is easy to self-heal after temperature rise; third, the "reinforcing" effect of the fiber can significantly improve the crack resistance of the filler; fourth, the reticular hardened cement can enhance the crack resistance of the filler. Under the condition of the prior art, the cracks generated in the asphalt pavement are difficult to self-heal even after temperature rise, and secondary diseases such as water damage are induced, which leads to structural damage of the pavement and greatly shortens the service life of the pavement.

[0044] 2. The equal-thickness particle size asphalt pavement of the application will not produce rut

[0045] Research shows that the reason why the equal-thickness particle size asphalt pavement will not produce rut is: the bearing capacity of the equal-thickness particle size asphalt pavement is mainly borne by a large number of "top" equal-thickness particle size macadam, and the plastic deformation will not occur at high temperature, i.e. rut will not occur; the shear strength of the equal-thickness particle size asphalt pavement is provided by a large number of equal-thickness particle size macadam, and is not composed of internal friction and cohesive force, i.e. it cannot be characterized by Mohr-Coulomb law, and the strength will not decrease due to high temperature; the stress-strain relationship of the equal-thickness particle size asphalt pavement shows close to linear elasticity in the whole temperature range (the temperature range of the pavement caused by climate), and not shows elastic-viscoplasticity-linear elasticity (low temperature), viscoelasticity (medium temperature) and viscoplasticity (high temperature).

[0046] 3. The construction process of the application can prolong the construction season, greatly reduce the serious dependence of the construction of the slurry mixture on high-temperature fine weather, and realize the opening of traffic after construction.

[0047] Under the condition of the prior art, the micro-surfacing is generally constructed in fine weather from May to October, and the forming speed is related to many climate factors such as sunlight intensity, temperature, humidity and wind speed; and the application can be constructed in low-temperature weather as long as it is not raining and not icing, which prolongs the construction season.

[0048] The application adopts vacuum water absorption, accelerates the forming speed, and opens traffic after construction; and in the prior art, moisture is volatilized naturally, and even if the micro-surfacing (1cm thick) is constructed in a fine weather in summer, the opening time of traffic needs about 2h, and if the thickness of the slurry mixture is greater than 2cm, even in a continuous high-temperature fine weather, it needs several days to open traffic.

[0049] 4, the present application innovates the design theory of asphalt pavement, distinguishes the functions of different structures in the asphalt pavement, and solves the paradox in the prior art

[0050] In the prior art, the whole pavement jointly resists rutting and jointly resists cracking, which is commonly known as "two ends of asphalt pavement", and the problem is that the resistance to rutting and the resistance to cracking cannot be considered at the same time. For example, increasing the powder-gum ratio can improve the anti-rutting performance, but the anti-cracking performance is poor; for example, using high-grade asphalt is beneficial to improving the anti-cracking performance, but the anti-rutting performance is poor, and so on. This is the paradox in the prior art, which causes great difficulty in the design and engineering practice of asphalt pavement.

[0051] The present application reasonably divides the functions of different structures in the asphalt pavement, and designs them according to their respective tasks, so that their performances are all optimal. In the asphalt pavement, the gravel skeleton is the main load bearer at high temperature, and is the determining factor of whether rutting occurs, so the "standing on the ground" equal-thickness particle size gravel that will not produce rutting is used to resist rutting; at low temperature, the filler is the main body of anti-cracking, and is the determining factor of whether cracking occurs, so the filler of the mixture of the mesh hardening cement, SBR modified asphalt, rubber powder and fiber with outstanding anti-cracking performance is used to resist cracking. As a result, the anti-rutting performance and the anti-cracking performance of the asphalt pavement are both good, the "two ends are considered at the same time" is realized, and the paradox in the prior art is solved.

[0052] 5, the present application is widely used

[0053] The pavement of the present application can be used for the upper layer of new construction, the overlay of maintenance engineering and bridge deck pavement, etc. DETAILED DESCRIPTION

[0054] The technical solutions and effects of the present application will be further described below in combination with specific examples, but the protection scope of the present application is not limited thereto.

[0055] Example 1

[0056] In this embodiment, a 4cm-thick emulsified asphalt rubber powder fiber slurry mixture penetration type pavement is made.

[0057] An emulsified asphalt rubber powder fiber slurry mixture penetration type pavement construction process, comprising the following steps:

[0058] 1) First application of asphalt

[0059] The construction shall be carried out in accordance with the requirements of (JTG F40-2004) "Technical Specification for Construction of Highway Asphalt Pavement". The first application of asphalt shall be hot rubber asphalt, with a dosage of 0.4m³. 3 / 1000m 2 ;

[0060] 2) Spreading gravel

[0061] The construction shall be carried out in accordance with the requirements of (JTG F40-2004) "Technical Specification for Construction of Asphalt Pavement on Highways", with a crushed stone application rate of 35m³. 3 / 1000m 2 Since the maximum particle size of the 2cm-4cm crushed stone is 4cm, which is equal to the road surface thickness, crushed stone with a particle size of 2cm-4cm is selected as the spreading material. The rule of thumb for determining the amount of spreading crushed stone is: the crushed stone should occupy ≥50% of the volume inside the road surface.

[0062] (iii) Compacted crushed stone

[0063] The requirements of (JTG F40-2004) "Technical Specification for Construction of Highway Asphalt Pavement" shall be followed.

[0064] (iv) Second application of asphalt

[0065] The construction was carried out in accordance with the requirements of (JTG F40-2004) "Technical Specification for Construction of Highway Asphalt Pavement". The second application of asphalt was cationic slow-setting fast-setting SBR modified emulsified asphalt, with a dosage of 0.5 m³. 3 / 1000m 2 ;

[0066] (v) Mixing, spreading and penetration of emulsified asphalt powder fiber slurry mixture

[0067] In this embodiment, emulsified asphalt:rubber powder:fiber = 15:35:0.6 is used. Based on the selected emulsified asphalt:rubber powder:fiber = 15:35:0.6, and assuming the amount of cement used by weight, a trial mixing was conducted. When the emulsified asphalt:rubber powder:fiber:cement = 15:35:0.6:3, the workability of the emulsified asphalt-rubber powder-fiber slurry mixture is good. This embodiment uses this ratio to calibrate the slurry seal machine and produce emulsified asphalt-rubber powder-fiber slurry mixture.

[0068] The emulsified asphalt is a cationic slow-cracking, fast-setting SBR modified emulsified asphalt; the specifications and quality of the materials used meet the requirements of (JTG F40-2004) "Technical Specification for Construction of Highway Asphalt Pavement".

[0069] The mixing, paving and penetration of the emulsified asphalt fiber cement slurry mixture are performed according to the requirements of "Technical Specification for Construction of Highway Asphalt Pavement" (JTG F40-2004) and "Construction Regulation for Pavement Slurry Seal" (CJJ 66-95);

[0070] Six) Vacuum water absorption

[0071] The vacuum water absorption is performed after the demulsification of the emulsified asphalt;

[0072] According to "Test of Demulsification Speed of Emulsified Asphalt" (T 0658-1993), the judgment method of the demulsification of the emulsified asphalt is that after the paving and penetration of the emulsified asphalt fiber cement slurry mixture are completed, a piece of white paper is pressed on the road surface every 5 minutes, the position of each pressing is not repeated, and when no brown spots are found on the white paper, the emulsified asphalt is demulsified. In this embodiment, no brown spots are found on the white paper after the emulsified asphalt is sprayed and pressed for the fifth time, that is, the emulsified asphalt is demulsified 25 minutes after the emulsified asphalt is sprayed;

[0073] The vacuum water absorption equipment includes a vacuum water absorption cloth, a vacuum water absorption pad, a vacuum water absorption pipe and a vacuum pump. The vacuum water absorption cloth is laid on the emulsified asphalt fiber cement slurry mixture which has been paved, the vacuum water absorption pad is laid on the vacuum water absorption cloth, and the vacuum water absorption pad is connected with the vacuum pump through the vacuum water absorption pipe;

[0074] The process of the vacuum water absorption is that the vacuum pump is started, the vacuum degree of the road surface is gradually increased, the water is absorbed, the vacuum degree is controlled at 0.08 MPa when the water absorption is normal, the vacuum degree is gradually increased when the water cannot be absorbed, and the water absorption is ended when the water cannot be absorbed for 2 minutes.

[0075] Seven) Rolling

[0076] The emulsified asphalt fiber cement slurry mixture penetration type road surface is formed by rolling 4-5 times with a 16t rubber wheel roller to further squeeze out the water and compact the gap filler of the gravel, and the traffic can be opened after the rolling.

[0077] Although the embodiments of the present application have been shown and described, it can be understood by those skilled in the art that various changes, modifications, replacements and variations can be made to the embodiments without departing from the principles and spirits of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A 4cm thick emulsified asphalt rubber powder fiber thin slurry mixture penetration type pavement, characterized in that, Firstly, the emulsified asphalt rubber powder fiber thin slurry mixture used in the pavement does not use stone, and the stiffness modulus of the filler is greatly reduced. On the one hand, the low stiffness modulus filler is not prone to cracking, and on the other hand, even if the low stiffness modulus filler produces cracks, it can easily self-heal after temperature rises; Secondly, rubber powder is a non-temperature sensitive material. At low temperatures, the modulus of rubber powder is much lower than that of asphalt. Rubber powder and asphalt are not synchronized in strain. When asphalt cracks encounter the stress field of rubber powder particles, it is easy to deflect the asphalt cracks and induce a large number of crazing around the rubber powder particles to consume a large amount of cracking energy. A large number of rubber powder particles will block the asphalt cracks and prevent the asphalt cracks from developing into through, long and wide pavement cracks. Moreover, the asphalt cracks can easily self-heal after the temperature rises; Thirdly, the "reinforcing" effect of the fiber can significantly improve the anti-cracking performance of the filler; Fourthly, the reticular hardened cement can enhance the anti-cracking performance of the filler; The pavement can improve the anti-cracking performance while ensuring the anti-rutting performance of the asphalt pavement. At the same time, it reduces the severe dependence of emulsified asphalt thin slurry mixture construction on high-temperature sunny weather and shortens the opening time of traffic; per 1000 m 2 The road surface is prepared from the following quantities of raw materials: first spread of asphalt 0.4 m 3 , spread of chippings 35 m 3 , second spread of asphalt 0.5 m 3 , emulsified asphalt mortar fibre slurry mixture as penetration material 10 m 3 - 40 m 3 ; The first time of spraying asphalt is hot rubber asphalt; The second time of spraying asphalt is cationic slow cracking and fast setting type SBR modified emulsified asphalt, and the evaporation residue is called SBR modified asphalt, with a content of 60%; The emulsified asphalt rubber powder fiber thin slurry mixture is prepared from the following raw materials in parts by weight: emulsified asphalt 15 parts, rubber powder 35 parts, fiber 0.6 parts, cement 3 parts; The main role of cement is to adjust the workability of the emulsified asphalt rubber powder fiber thin slurry mixture, so that it remains uniform, does not secrete water, and does not separate during the construction process. The consistency is 2cm-3cm. The emulsified asphalt rubber powder fiber thin slurry mixture with such construction performance is described as good workability. In addition, it has two functions: one is to adjust the demulsification time of the emulsified asphalt waste tire rubber powder fiber thin slurry mixture; the other is to form a reticular hardened cement structure in the pavement to improve the anti-cracking performance and anti-rutting performance of the pavement; The emulsified asphalt is cationic slow cracking and fast setting type SBR modified emulsified asphalt; The maximum particle size of the sprayed gravel is equal to the thickness of the pavement. Gravel with a particle size of 2cm-4cm is used as the sprayed gravel, and the content of the largest particle size gravel is ≥50%, and the volume of the sprayed gravel is the bulk volume; The rubber powder is waste tire rubber powder, with a particle size of 10 mesh-30 mesh; The fiber is one or more of glass fiber, polypropylene fiber, polyester fiber, lignin fiber and mineral fiber, with a length of 2cm-3cm; The cement is fast-hardening Portland cement, with a strength grade of 32.5; The construction process of the emulsified asphalt rubber powder fiber thin slurry mixture penetration type pavement includes the following steps: Firstly, spraying asphalt for the first time Secondly, spraying gravel Thirdly, stabilizing gravel Fourthly, spraying asphalt for the second time Fifthly, mixing, paving and penetrating the emulsified asphalt rubber powder fiber thin slurry mixture Sixthly, vacuum water absorption The vacuum water absorption is performed after the emulsified asphalt demulsification; the judgment method of the emulsified asphalt demulsification is that after the emulsified asphalt fiber cement powder thin slurry mixture is paved and penetrated, every 5 minutes, a white water absorption paper is gently pressed on the road surface, the position of each pressing is not repeated, when no brown spots are seen on the white paper, the emulsified asphalt has been demulsified; The vacuum pump is started, the vacuum degree in the road surface is gradually increased, the water is absorbed, when the water absorption is normal, the vacuum degree is controlled at 0.08 MPa, when the water cannot be absorbed, the vacuum degree is gradually increased to absorb the water, until the vacuum degree is increased to 0.13 MPa, when the water cannot be absorbed for 2 minutes, the water absorption is ended; The vacuum water absorption equipment includes a vacuum water absorption filter cloth, a vacuum water absorption pad, a vacuum water absorption pipe and a vacuum pump, wherein the vacuum water absorption filter cloth is laid on the emulsified asphalt fiber cement powder thin slurry mixture which has been paved, the vacuum water absorption pad is laid thereon, the vacuum water absorption pad is connected with the vacuum pump through the vacuum water absorption pipe; Seven) rolling The emulsified asphalt fiber cement powder thin slurry mixture penetration type road surface is formed by rolling 4-5 times with a 16t rubber wheel roller, further extruding the water and compacting the gap filler.