阅读说明：本技术 一种沥青路面超薄高抗滑表层及其施工方法 (Ultrathin high-skid-resistance surface layer of asphalt pavement and construction method thereof ) 是由 熊锐 宗有杰 杨发 关博文 盛燕萍 牛冬瑜 李闯 田海涛 瞿春璞 纪括 冯宝珠 于 2019-11-27 设计创作，主要内容包括：一种沥青路面超薄高抗滑表层及其施工方法,包括磨耗层和粘层,磨耗层采用集料公称最大粒径为6.35mm的沥青玛蹄脂碎石混合料,并提出了一种新形式的级配范围SMA-7,沥青玛蹄脂碎石混合料由煅烧铝矾土与石灰岩组成,且相互之间形成差异磨光,将粒径为4.75mm～6.35mm与6.35mm～9.5mm的石灰岩通过煅烧铝矾土等体积代替,煅烧铝矾土矿料中三氧化二铝的含量不低于88％；煅烧铝矾土的磨光值大于石灰岩的磨光值,煅烧铝矾土的掺配量按质量分数计为10％～15％；磨耗层通过粘层与沥青路面粘结成为一体。本发明能够提高路面的抗滑性、耐磨性及行车的舒适性与安全性,降低路面的行车噪音。(An ultrathin high-skid-resistance surface layer of an asphalt pavement and a construction method thereof comprise a wearing layer and a bonding layer, wherein the wearing layer adopts an asphalt mastic crushed stone mixture with the aggregate nominal maximum grain size of 6.35mm, a new-form grading range SMA-7 is provided, the asphalt mastic crushed stone mixture consists of calcined bauxite and limestone which form differential polishing with each other, the limestone with the grain sizes of 4.75-6.35 mm and 6.35-9.5 mm is replaced by the calcined bauxite with equal volume, and the content of aluminum oxide in the calcined bauxite mineral aggregate is not lower than 88%; the polishing value of the calcined bauxite is larger than that of limestone, and the mixing amount of the calcined bauxite is 10-15% by mass; the wearing layer is bonded with the asphalt pavement into a whole through the adhesive layer. The invention can improve the skid resistance and the wear resistance of the road surface and the comfort and the safety of driving and reduce the driving noise of the road surface.)

1. The utility model provides an ultra-thin high cling compound top layer of bituminous paving which characterized in that: comprises a wearing layer and an adhesive layer;

the wearing layer adopts an aggregate mixture of the asphalt mastic macadam with the nominal maximum grain diameter of 6.35 mm;

the asphalt mastic macadam mixture consists of calcined bauxite and limestone, the limestone with the grain sizes of 4.75-6.35 mm and 6.35-9.5 mm is replaced by the calcined bauxite with the same volume, and the content of aluminum oxide in the calcined bauxite mineral aggregate is not lower than 88%; the polishing value of the calcined bauxite is greater than that of limestone, and the mixing amount of the calcined bauxite is 10-15% by mass; the wearing layer is bonded with the asphalt pavement into a whole through the bonding layer.

2. The ultrathin high-slip surface layer for an asphalt pavement according to claim 1, wherein the gradation range of the mixture of asphalt mastic and crushed stone is as shown in the following table:

3. the ultrathin high-slip surface layer for asphalt pavements as claimed in claim 1, characterized in that: the grinding value of calcined bauxite in the mixture of the asphalt mastic macadam is 1.5-2 times of that of limestone.

4. The ultrathin high-slip surface layer for asphalt pavements as claimed in claim 1, characterized in that: the adhesive layer is composed of SBS modified emulsified asphalt and hot SBS modified asphalt, and the hot SBS modified asphalt is sprayed after the SBS modified emulsified asphalt is demulsified.

5. The ultrathin high-slip surface layer for asphalt pavements as claimed in claim 1, characterized in that: the thickness of the surface layer was 20 mm.

6. The construction method of the ultrathin high-skid resistance surface layer of the asphalt pavement is characterized by comprising the following steps of:

milling and planing an upper layer of the asphalt pavement, and cleaning the pavement;

secondly, repairing the diseases generated on the pavement;

thirdly, spraying a sticky layer on the upper layer of the dried asphalt pavement;

paving the prepared asphalt mastic gravel mixture on a sticky layer, wherein the asphalt mastic gravel mixture is composed of calcined bauxite and limestone, the limestone with the particle sizes of 4.75-6.35 mm and 6.35-9.5 mm is replaced by the calcined bauxite with the same volume, the content of aluminum oxide in the calcined bauxite mineral aggregate is not lower than 88%, the polishing value of the calcined bauxite is greater than that of the limestone, and the mixing amount of the calcined bauxite is 10-15% by mass fraction;

and step five, forming the road surface, maintaining in a natural cooling mode, and opening traffic when the road surface is cooled to 45-50 ℃.

7. The construction method according to claim 6, wherein: the diseases in the second step comprise reflection cracks, pits and tracks, and for pavement cracks, when the width of the cracks is less than or equal to 3mm, the cracks do not have branch seams, are crushed, sink or slurry dredged, and the cracks are filled with emulsified asphalt; when the width of the seam is larger than 3mm, performing seam filling treatment by using seam filling glue, and attaching a seam sticking belt after the seam is filled by using the seam filling glue;

TABLE 1

Evaluation index General type Penetration degree (0.1mm) 30～70 Softening Point (. degree. C.) ≥80 Flow value (mm) ≤5 Elastic recovery (%) 30～70 Stretching at low temperature By (-10 ℃ C.)

TABLE 2

Technical index Technical requirements Softening Point (. degree. C.) ≥80 Low temperature brittle fracture (. degree. C.) -20 Tensile strength (KN/m) ≥40 Elongation (%) ≤10 Impermeability (pressure 0.1MPa, 30min) Is impervious to water Elastic recovery 25 ℃ (%) ≥90 Fabric temperature resistance (DEG C) ≥250 Heat resistance No flow and no leakage at 130 DEG C Thickness (mm) ≥2

The technical index requirements of the joint filling adhesive and the technical index requirements of the joint tape are respectively shown in the table 1 and the table 2.

8. The construction method according to claim 6, wherein: when spraying the adhesive layer, uniformly spraying the SBS modified emulsified asphalt on the dried milled and milled asphalt pavement for one time, wherein the spraying amount is 0.3-0.4kg/m²After the SBS modified emulsified asphalt is fully demulsified, the hot SBS modified asphalt is uniformly sprayed for one time, and the spraying amount is 0.4-0.5kg/m²。

9. The construction method according to claim 6, wherein: paving the four-way pipe by a paver, controlling the paving speed at 10m/min, carrying out paving in two steps, and checking the thickness of the paving layer, a road arch and a cross slope in the paving process to avoid the segregation phenomenon of a mixture; after paving, a road roller with double steel wheels is adopted to perform initial pressing, re-pressing and final pressing on the road surface, an aqueous solution containing a separant is sprayed or brushed on the wheel of the road roller in the rolling process, the spraying is atomized, and the water spraying amount is equal to the degree that the wheel is not adhered.

10. The construction method according to claim 6, wherein: after the paving of the mixture of the asphalt mastic and the macadam is finished, the ultrathin high-skid-resistance surface layer of the asphalt pavement is closely attached to the kerbstone and other structures, and the water accumulation area is eliminated.

Technical Field

The invention belongs to the field of road engineering, and particularly relates to an ultrathin high-skid-resistance surface layer of an asphalt pavement and a construction method thereof.

Background

With the rapid development of road construction in China, road engineering is changed from reconstruction to reconstruction and maintenance, the service time of many roads is increased, the service function of the surface of the pavement is rapidly reduced, the anti-skid performance is particularly obviously attenuated, the driving safety is reduced, and in order to continuously maintain good surface service function of the pavement, a new-grade ultrathin high-anti-skid surface layer of the asphalt pavement is required to be researched.

Disclosure of Invention

The invention aims to solve the problem that the performance of the asphalt pavement is poor after long-term service in the prior art, and provides an ultrathin high-skid-resistance surface layer of the asphalt pavement and a construction method thereof.

In order to achieve the purpose, the invention has the following technical scheme:

an ultrathin high-skid-resistance surface layer of an asphalt pavement comprises a wearing layer and a bonding layer;

the wearing layer adopts an aggregate mixture of the asphalt mastic macadam with the nominal maximum grain diameter of 6.35 mm;

the asphalt mastic macadam mixture consists of calcined bauxite and limestone, the limestone with the grain sizes of 4.75-6.35 mm and 6.35-9.5 mm is replaced by the calcined bauxite with the same volume, and the content of aluminum oxide in the calcined bauxite mineral aggregate is not lower than 88%; the polishing value of the calcined bauxite is greater than that of limestone, and the mixing amount of the calcined bauxite is 10-15% by mass; the wearing layer is bonded with the asphalt pavement into a whole through the bonding layer.

The gradation range of the mixture of the asphalt mastic macadam is shown in the following table:

preferably, in an embodiment of the ultrathin high anti-slip surface layer of the asphalt pavement of the invention, the grinding value of the calcined bauxite in the asphalt mastic macadam mixture is 1.5 times to 2 times that of limestone.

Preferably, in an embodiment of the ultrathin high-slip surface layer of the asphalt pavement of the present invention, the adhesive layer is composed of SBS modified emulsified asphalt and hot SBS modified asphalt, and the hot SBS modified asphalt is uniformly sprayed after the SBS modified emulsified asphalt is demulsified.

Preferably, the thickness of the ultrathin high-skid-resistance surface layer of the asphalt pavement is 20 mm.

The invention also provides a construction method of the ultrathin high-skid-resistance surface layer of the asphalt pavement, which comprises the following steps:

milling and planing an upper layer of the asphalt pavement, and cleaning the pavement;

secondly, repairing the diseases generated on the pavement;

thirdly, spraying a sticky layer on the upper layer of the dried asphalt pavement;

paving the prepared asphalt mastic gravel mixture on a sticky layer, wherein the asphalt mastic gravel mixture is composed of calcined bauxite and limestone, the limestone with the particle sizes of 4.75-6.35 mm and 6.35-9.5 mm is replaced by the calcined bauxite with the same volume, the content of aluminum oxide in the calcined bauxite mineral aggregate is not lower than 88%, the polishing value of the calcined bauxite is greater than that of the limestone, and the mixing amount of the calcined bauxite is 10-15% by mass fraction;

and step five, forming the road surface, maintaining in a natural cooling mode, and opening traffic when the road surface is cooled to 45-50 ℃.

Preferably, in an embodiment of the method for constructing the ultrathin high-skid-resistance surface layer of the asphalt pavement, the defects in the second step include reflection cracks, pits and ruts, and for pavement cracks, when the width of the crack is less than or equal to 3mm, the crack has no branch crack, is broken, is sunk or is drenched, and the crack is grouted by emulsified asphalt; when the width of the seam is larger than 3mm, performing seam filling treatment by using seam filling glue, and attaching a seam sticking belt after the seam is filled by using the seam filling glue; the technical index requirements of the crack pouring adhesive and the technical index requirements of the joint tape are respectively shown in tables 1 and 2:

TABLE 1

TABLE 2

Technical index	Technical requirements
		Softening Point (. degree. C.)	≥80
Low temperature brittle fracture (. degree. C.)	-20
		Tensile strength (KN/m)	≥40
Extension ofPercentage (%)	≤10
		Impermeability (pressure 0.1MPa, 30min)	Is impervious to water
Elastic recovery 25 ℃ (%)	≥90
		Fabric temperature resistance (DEG C)	≥250
Heat resistance	No flow and no leakage at 130 DEG C
		Thickness (mm)	≥2

Preferably, in an embodiment of the method for constructing the ultrathin high-skid-resistance surface layer of the asphalt pavement, when the adhesive layer is sprayed in the third step, the SBS modified emulsified asphalt is uniformly sprayed on the upper layer of the dry asphalt pavement for one time, wherein the spraying amount is 0.3-0.4kg/m²After the SBS modified emulsified asphalt is fully demulsified, the hot SBS modified asphalt is uniformly sprayed for one time, and the spraying amount is 0.4-0.5kg/m²。

Preferably, in one embodiment of the construction method of the ultrathin high-skid-resistance surface layer of the asphalt pavement, the four-way process is paved by a paver, the paving speed is controlled at 10m/min, the paving is carried out in two steps, and the thickness of the paving layer, a road arch and a cross slope are checked in the paving process to avoid segregation; after paving, a road roller with double steel wheels is adopted to perform initial pressing, re-pressing and final pressing on the road surface, an aqueous solution containing a separant is sprayed or brushed on the wheel of the road roller in the rolling process, the spraying is atomized, and the water spraying amount is equal to the degree that the wheel is not adhered.

Preferably, in an embodiment of the construction method, after the paving of the mixture of asphalt mastic and macadam is finished, the ultrathin high-skid-resistance surface layer of the asphalt pavement is attached to the kerbstone and other structures, and the water accumulation area is eliminated.

Compared with the prior art, the ultrathin high-slip-resistance surface layer has the following beneficial effects: as the screen hole span of the square hole screen in China is larger between 4.75mm and 9.5mm, a grading range with the nominal maximum grain size of aggregate of 6.35mm exists, namely SMA-7 between SMA-5 and SMA-10, 1/4inch (6.35 mm) is selected in the invention, namely the nominal maximum grain size of the aggregate is 6.35mm, and the ultrathin high-skid-resistance surface layer of the asphalt pavement is designed. Compared with the traditional asphalt mastic macadam mixture, the asphalt mastic macadam mixture has better pavement performance and structural characteristics. According to the ultrathin high-skid resistance surface layer, high-polishing-value aggregate (calcined bauxite) and low-polishing-value aggregate (common limestone) are mixed according to a certain proportion, so that differential polishing can be better formed between the calcined bauxite and the limestone, the polishing value of the calcined bauxite is greater than that of the limestone, a rougher macro-microstructure and a rougher microstructure can be formed under the action of long-term driving load, and the skid resistance and the wear resistance of a road surface are improved. The ultrathin high-skid-resistance surface layer has a simple structure, greatly improves the skid resistance of the road surface, the comfort and the safety of road driving, reduces the driving noise of the road surface and the like under the condition of taking the road performance and the economic benefit of the aggregate into consideration, and integrally improves the surface use function of the road surface.

Compared with the prior art, the construction method of the ultrathin high-skid-resistance surface layer reasonably utilizes the different polishing characteristics among aggregates, improves the skid resistance of the pavement, has a more compact structure, can remarkably improve the skid resistance, the wear resistance and the comfort and the safety of driving under the condition of meeting the road performance, prevents the surface water from seeping, reduces the driving noise of the pavement and the like, comprehensively improves the surface use function of the pavement, and prolongs the service life of the pavement.

Detailed Description

The present invention will be described in further detail with reference to specific examples.

The ultrathin high-skid-resistance surface layer of the asphalt pavement comprises a wearing layer and an adhesive layer, wherein the wearing layer is bonded with the asphalt pavement into a whole through the adhesive layer. The wearing layer adopts an aggregate mixture of the asphalt mastic macadam with the nominal maximum grain diameter of 6.35mm, the grading range is determined according to the volume parameter of the aggregate, so when calcined bauxite is used for replacing part of limestone, the same volume of the bauxite is used for replacing the limestone, and the grain diameters of the replaced part of limestone are 4.75-6.35 mm and 6.35-9.5 mm.

The mineral aggregate gradation range of the ultra-thin high-slip surface layer of the asphalt pavement of the invention is shown in the following table.

The technical characteristics of the ordinary limestone aggregate and the calcined bauxite are shown in the following table.

Ordinary limestone

Calcined bauxite

Item	Unit of	Technical requirements	Test results	Test method
					Crush number	％	≯26	5.22	T0316
Polishing value	％	≮42	82	T0321
					Adhesion property	％	≮5	5	T0616
Los Angeles abrasion loss	％	≯28	7.31	T0317

From the comparison in the above table, it can be seen that calcined bauxite is significantly better than ordinary limestone in terms of crush number, burnishing number, and loss of rocky rock abrasion, and thus provides good differential burnishing between the two aggregates. The content of alumina in the calcined bauxite ore material is not less than 88 percent. The mixing amount of the calcined bauxite is 10 to 15 percent in consideration of the economic benefit of the aggregate and the differential polishing performance of the pavement. Because the grading design of the ultrathin high-anti-skid surface layer is the mixture of asphalt mastic crushed stones (SMA-7) with the aggregate nominal maximum grain diameter of 6.35mm, and the thickness of the ultrathin high-anti-skid surface layer is designed to be 20mm in order to improve the wear resistance and durability of the ultrathin high-anti-skid surface layer.

The invention relates to a construction method of an ultrathin high-skid-resistance surface layer of an asphalt pavement, which comprises the following steps:

if the original road surface is milled, the milling depth of 20mm is controlled, and milling materials and road surface sundries on the road surface are cleaned in time in the milling process. After the original pavement is milled and planed, the defects of reflection cracks, pit grooves, tracks and the like generated by a base layer, a surface layer and the like on the pavement are treated according to the standard requirements, and a good foundation is provided for the pavement of the ultrathin high-skid-resistance surface layer.

For pavement cracks, when the width of the crack is less than or equal to 3mm, no branch crack, crushing, sinking or grout pumping and other diseases exist at the crack, and emulsified asphalt is adopted for crack pouring; and when the width of the seam is larger than 3mm, performing seam filling treatment by using seam filling glue, and sticking a seam tape after the seam filling by using the seam filling glue. The crack repair work should be arranged before the rainy season comes, and construction is required in the season that the crack is basically in a fully opened state.

The corresponding evaluation indexes of the joint sealant are shown in the following table:

technical index requirement of crack pouring glue

Evaluation index	General type
		Penetration degree (0.1mm)	30～70
Softening Point (. degree. C.)	≥80
		Flow value (mm)	≤5
Elastic recovery (%)	30～70
		Stretching at low temperature	By (-10 ℃ C.)

Technical index requirement of seam-sticking belt

Technical index	Technical requirements
		Softening Point (. degree. C.)	≥80
Low temperature brittle fracture (. degree. C.)	-20
		Tensile strength (KN/m)	≥40
Elongation (%)	≤10
		Impermeability (pressure 0.1MPa, 30min)	Is impervious to water
Elastic recovery 25 ℃ (%)	≥90
		Fabric temperature resistance (DEG C)	≥250
Heat resistance	No flow and no leakage at 130 DEG C
		Thickness (mm)	≥2

When spraying the adhesive layer, firstly, uniformly spraying the SBS modified emulsified asphalt on the upper layer of the dry asphalt pavement once, wherein the spraying amount is 0.3-0.4kg/m²After the SBS modified emulsified asphalt is fully demulsified, the hot SBS modified asphalt is uniformly sprayed for one time, and the spraying amount is 0.4-0.5kg/m². Under the requirement of the production mix proportion of the asphalt mixture, preparing the asphalt mixture in an asphalt mixture mixing field according to the requirement, transporting the asphalt mixture to a construction site, and monitoring the temperature of the asphalt mixture constantly. In the process of paving the mixture, the speed of the paver is controlled at 10m/min, paving is carried out in two steps, and the thickness of the paving layer, the road arch, the cross slope and the like are checked at any time in the paving process. Meanwhile, the spreading process should be adjusted at any time to avoid the segregation of the mixture as much as possible. After the mixture is paved, the rolling operation is immediately organized, and two 13-ton double-steel-wheel road rollers are adopted for primary pressing, secondary pressing and final pressing.

In the rolling process, the rubber-tyred roller is forbidden to roll, and the phenomenon of 'pumping' can be generated in the rolling process of the rubber-tyred roller, so that the fine aggregate and the asphalt float upwards, and the framework structure of the hot mixed material can be damaged.

The rolling wheel keeps clean in the rolling process, and the sticking wheel with the mixture is immediately removed. Spraying or brushing an aqueous solution containing a separant on the road roller wheel; the water spraying amount is controlled during rolling and is atomized, and the water spraying amount is controlled to be not adhered to the roller. After the ultrathin high-skid-resistance surface layer is laid, the ultrathin high-skid-resistance surface layer is required to be closely attached to the curb and other structures, and water accumulation cannot occur.

On the road surface shaped on the same day, various mechanical equipment or vehicles should not be parked. The paved road surface should be protected, kept clean and tidy, should not cause pollution, and should not stack the soil or sundries generated by construction on the asphalt road surface.

After construction, the construction is maintained in a natural cooling mode, and when the road surface is cooled to 45-50 ℃, the traffic is opened.

The invention reasonably utilizes the differential polishing characteristics among aggregates to improve the skid resistance of the pavement, the prepared ultrathin high-skid-resistance surface layer is of a skeleton compact structure, the friction coefficient and the skid resistance of the pavement are greatly improved by utilizing the differential polishing characteristics among new SMA-7 gradation, calcined bauxite, aggregates and the like, the problem that the skid resistance and the skid resistance of the pavement are not durable is solved, and the surface use function of the pavement is comprehensively improved. The ultrathin high-skid-resistance surface layer of the asphalt pavement can effectively prevent surface water from seeping, reduce the driving noise, improve the safety and comfort of driving on the pavement, and prolong the service life of the pavement.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the technical solution of the present invention, and it should be understood by those skilled in the art that the technical solution can be modified and replaced by a plurality of simple modifications and replacements without departing from the spirit and principle of the present invention, and the modifications and replacements also fall within the protection scope defined by the claims.