US20170167085A1

US20170167085A1 - Patch and method for repairing asphalt pavement

Info

Publication number: US20170167085A1
Application number: US15/365,154
Authority: US
Inventors: Feng Li; Tinggang LI; Xingyi ZHU; Li Li; Yuchuan DU; Xiaopei SHI
Original assignee: Research Institute of Highway Ministry of Transport
Current assignee: Research Institute of Highway Ministry of Transport
Priority date: 2015-12-10
Filing date: 2016-11-30
Publication date: 2017-06-15
Also published as: HK1223991A1; CN105568834A

Abstract

A patch and a method for repairing an asphalt pavement are provided. The patch includes a first asphalt layer having first and second bonding surfaces opposite to each other, a second asphalt layer having third and fourth bonding surfaces opposite to each other, the third bonding surface of the second asphalt layer facing the second bonding surface of the first asphalt layer, a textile layer disposed between the second bonding surface of the first asphalt layer and the third bonding surface of the second asphalt layer, and a crushed stone layer disposed on the first bonding surface of the first asphalt layer. A pothole of an asphalt pavement may be repaired quickly by using the patch according to the present disclosure. Moreover, the patch according to the present disclosure may not pollute environment around roads.

Description

BACKGROUND

1. Field
The present disclosure relates to a field of maintaining an asphalt pavement, more particularly, to a patch and a method for repairing an asphalt pavement.
2. Description of the Related Art
Distress, such as cracks, potholes or the like, will be inevitably generated by a coupling effect of traffic loads and an environment after an asphalt pavement is opened to traffic, so that driving comfort and safety are negatively affected, and thus the asphalt pavement must be maintained and repaired in time.
FIGS. 1A to 1C are photos illustrating development states of a crack-type distress of an asphalt pavement, and more particularly, FIG. 1A is a photo illustrating a crack-type distress including a single crack, FIG. 1B is a photo illustrating a crack-type distress including block-shaped cracks, and FIG. 1C is a photo illustrating a crack-type distress including net-shaped cracks.
As shown in FIGS. 1A to 1C, the development stage of the crack-type distress of the asphalt pavement includes the single crack, the block-shaped cracks, the net-shaped cracks and presence of the potholes in sequence. An object of maintaining and repairing the asphalt pavement is to deal with the single crack in time such that the single crack is prevented from expanding to form the block-shaped cracks, the net-shaped cracks or the pothole. Once the net-shaped cracks or potholes occur in the asphalt pavement, it needs to be repaired by following steps:
Before a partial damage of the asphalt pavement is repaired, a regular recessing is performed at the partial damage, a rectangular outline of the net-shaped cracks or potholes is determined according to a principle of “repairing a circular pothole using a square patch” so that each of sides of the rectangular outline extends into an intact portion of the pavement by at least 10 cm (that is, loose and crushed materials of the pavement are dug, up to a position where a hard portion of the pavement is located, and then the dug materials are scooped out).
Crushed stones and residues inside and around the pothole are removed such that there are no sundries such as mud, rain, snow, ice and the like in the pothole. Also, the pothole should have neat cut edges, and the removing of the residues is preformed until a solid surface occurs.
Before an asphalt mixture are laid in the pothole, an adhesive oil is uniformly applied on side and bottom surfaces of the pothole to infiltrate bare stones on the surfaces of the pothole, thereby improving a bonding effect between the asphalt mixture and initial materials of the pavement.
The asphalt mixture is poured into the pothole until the mixture is filled to be higher than a surface of the pavement by about 1 to 2 cm. A center of the asphalt mixture filled in the pothole which is convex should be slightly higher than the surface of the pavement.
After the asphalt mixture is uniformly laid, the asphalt mixture is tamped by using appropriate tamping tools and methods (such as a small vibrating tamper and a small road roller) selected according to a size and a depth of the repaired area. If it is found that the asphalt mixture is lack at any local position during the tamping process, additional asphalt mixture should be complemented immediately. After the tamping process is completed, the edges of the pothole may be sealed with asphalt if necessary.
The surface of the repaired pothole should be flat and traceless, and sides and corners of the repaired pothole are well tamped and do not have loose phenomenon or the like. Traffic will be opened after the pothole is repaired.
Moreover, in a case where the pothole has a depth more than 5 cm, a plurality of asphalt mixture layers each having a thickness of 3 to 5 cm are filled and tamped in the pothole in sequence.
However, the above repairing method has following problems: the processes are complicated, the traffic is seriously affected, and waste materials and harmful gas are easily generated, thereby polluting environment around roads. Furthermore, for example, it takes 1 hour to repair 1 m²of pothole by using the above repairing method.

SUMMARY

An object of the present disclosure is to provide a patch for repairing an asphalt pavement which is capable of repairing a pothole on the asphalt pavement quickly.
Another object of the present disclosure is to provide a method for repairing an asphalt pavement quickly.
There is provided a patch for repairing an asphalt pavement including: a first asphalt layer having first and second bonding surfaces opposite to each other; a second asphalt layer having third and fourth bonding surfaces opposite to each other, the third bonding surface of the second asphalt layer facing the second bonding surface of the first asphalt layer; a textile layer disposed between the second bonding surface of the first asphalt layer and the third bonding surface of the second asphalt layer; and a crushed stone layer disposed on the first bonding surface of the first asphalt layer.
The patch may further include a release layer disposed on and covering the fourth bonding surface of the second asphalt layer.
The textile layer may include an alkali-resistant glass fiber mesh or a basalt fiber bidirectional cloth.
The textile layer may have a thickness in a range of 1 to 2.5 mm, and the first asphalt layer, the second asphalt layer and the textile layer may have an entire thickness in a range of 2 to 4.5 mm.
The crushed stone layer may include crushed stones each having a particle size in a range of 1.18 to 4.75 mm, and have a coverage rate of 75% to 95% on the first bonding surface of the first asphalt layer.
The crushed stone layer may have a thickness in a range of 1 to 5 mm.
The release layer may include a polyethylene blown thin film, and have a thickness equal to or less than 0.05 mm.
The patch may have a thickness in a range of 5 to 8.5 mm.
There is also provided a method for repairing an asphalt pavement including: pretreating an area of the asphalt pavement to be treated, according to distress characteristic of the asphalt pavement; and laying a patch on the pretreated area of the asphalt pavement, and tamping the patch, wherein the patch includes: a first asphalt layer having first and second bonding surfaces opposite to each other; a second asphalt layer having third and fourth bonding surfaces opposite to each other, the third bonding surface of the second asphalt layer facing the second bonding surface of the first asphalt layer; a textile layer disposed between the second bonding surface of the first asphalt layer and the third bonding surface of the second asphalt layer; and a crushed stone layer disposed on the first bonding surface of the first asphalt layer.
The pretreating may include: spraying a curing agent to the area of the asphalt pavement to be treated when the distress characteristic of the area of the asphalt pavement to be treated has a partially loose state, or filling the area of the asphalt pavement to be treated with a sealant when the distress characteristic of the area of the asphalt pavement to be treated includes a crack having a width greater than 5 mm or a depth greater than 10 mm; and applying an adhesive on the area of the asphalt pavement to be treated.
An asphalt pavement may be repaired quickly by using the patch according to the present disclosure. Also, the method for repairing the asphalt pavement according to the present disclosure has simple processes and high efficiency, may not produce waste materials, and may not pollute environment around roads.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and/or other objects and advantages of the inventive concepts will be apparent and more clearly understood from the following description of embodiments taken in conjunction with the accompanying drawings in which:

FIGS. 1A to 1C are photos illustrating development states of a crack-type distress of an asphalt pavement, and more particularly, FIG. 1A is a photo illustrating a crack-type distress including a single crack, FIG. 1B is a photo illustrating a crack-type distress including block-shaped cracks, and FIG. 1C is a photo illustrating a crack-type distress including net-shaped cracks; and

FIG. 2 is a structural schematic view illustrating a patch for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

A patch and a method for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure now will be described in detail with reference to the accompanying drawings.
The present disclosure may, however, be embodied in many different forms, and should not be construed as being limited to the specific embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the inventive concepts to those skilled in the art.
In the accompanying drawings, like reference numerals refer to like or similar elements throughout.
In a conventional method of repairing the net-shaped cracks or potholes on an asphalt pavement, an area at which the net-shaped cracks are located is excavated locally or an area at which the potholes have occurred is removed, and then a hot mix asphalt mixture or a cold repair asphalt mixture is filled therein, which may cause complicated processes, low efficiency and serious impact on traffic, as well as easy generation of waste materials and harmful gas polluting environment around roads. Therefore, the present disclosure provides a patch and a method for repairing an asphalt pavement which is capable of repairing a pothole on the asphalt pavement quickly and/or may not pollute the surrounding environment.
Hereinafter, a patch 100 for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure will be described.
FIG. 2 is a structural schematic view illustrating a patch for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure.
Referring to FIG. 2, the patch 100 according to an exemplary embodiment of the present disclosure includes: a first asphalt layer 110 having a first bonding surface 111 and a second bonding surface 112 opposite to each other; a second asphalt layer 120 having a third bonding surface 121 and a fourth bonding surface 122 opposite to each other, the third bonding surface 121 of the second asphalt layer 120 facing the second bonding surface 112 of the first asphalt layer 110; a textile layer 130 disposed between the second bonding surface 112 of the first asphalt layer 110 and the third bonding surface 121 of the second asphalt layer 120; a crushed stone layer 140 disposed on the first bonding surface 111 of the first asphalt layer 110; and an release layer 150 disposed on the fourth bonding surface 122 of the second asphalt layer 120.
The first bonding surface 111 of the first asphalt layer 110 may be a front surface of the first asphalt layer 110, and the second bonding surface 112 of the first asphalt layer 110 may be a rear surface of the first asphalt layer 110. The third bonding surface 121 of the second asphalt layer 120 may be a surface facing the second bonding surface 112 of the first asphalt layer 110, and the fourth bonding surface 122 of the second asphalt layer 120 may be a surface opposite to the third bonding surface 121.
The first asphalt layer 110 and the second asphalt layer 120 in the patch 100 may have water-resistance property, and may be made of any suitable materials. For example, the first asphalt layer 110 and the second asphalt layer 120 may include polymer modified asphalt which are formed by mixing components such as matrix asphalt, rubber powder, SBS, extract oil, filler and the like, and then reacting the components. However, the present disclosure is not limited thereto, and the first asphalt layer and the second asphalt layer may be formed of any suitable materials which meet technical parameters shown in following Table 1.

TABLE 1

technical parameters of materials for forming
the first and second asphalt layers

	Item	Requirement

	Penetration, 0.1 mm	70~120
	Softening point, ° C.	≧80
	5° C. ductility, mm	≧40

According to the patch 100 according to an exemplary embodiment of the present disclosure, the textile layer 130 positioned between the second bonding surface 112 of the first asphalt layer 110 and the third bonding surface 121 of the second asphalt layer 120 determines the shape of the patch 100 during calendaring and prevents deformation. The textile layer 130 may be made of any suitable high-strength materials. For example, the textile layer 130 may be made of an alkali-resistant glass fiber mesh or a basalt fiber bidirectional cloth. However, the present disclosure is not limited thereto, and the textile layer may be made of any suitable materials which meet technical parameters shown in following Table 2. Herein, it should be noted that the alkali-resistant glass fiber mesh may conform to requirements of Standard JC/T 841, and the basalt fiber bidirectional cloth may conform to requirements of Standard JT/T 776.2 in horizontal and vertical directions.

TABLE 2

technical parameters of the textile layer

	Item	Requirement

	Maximum tension, N/50 mm	≧1400
	Elongation at maximum tension, %	1.0~10.0
	Thickness, mm	2.0 ± 0.5
	Mass per unit area, g/m²	≧230

The textile layer 130 may have a thickness in a range of 1 to 2.5 mm. If the thickness of the textile layer 130 is too thin, tensile properties of the patch 100 may be negatively affected; and if the thickness of the textile layer 130 is too thick, an entire thickness of the patch 100 may be negatively affected, thereby negatively affecting flatness of the asphalt pavement.
The textile layer 130 may be impregnated with an asphalt material. More specifically, the first asphalt layer 110 may directly contact the textile layer 130 such that the asphalt material included in the first asphalt layer 110 is impregnated into the textile layer 130. The second asphalt layer 120 may directly contact the textile layer 130 such that the asphalt material included in the second asphalt layer 120 is impregnated into the textile layer 130. In other words, the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 may be coupled to each other to form an integrity.
In a non-limiting exemplary embodiment of the present disclosure, a structure in which the textile layer 130 is surrounded by the asphalt material (i.e. a structure of the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 sequentially stacked) may be obtained by impregnating the textile layer 130 into an asphalt material for forming the first asphalt layer 110 and the second asphalt layer 120 and then calendaring-molding the impregnated textile layer 130. In an exemplary embodiment of the present disclosure, the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 may have an entire thickness in a range of 2 to 4.5 mm. If the entire thickness of the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 is too thin, the asphalt material may not be sufficiently impregnated into the textile layer. If the entire thickness of the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 is too thick, flatness of the asphalt pavement may be negatively affected.
The crushed stone layer 140 may be positioned on the first bonding surface 111 of the first asphalt layer 110, thereby preventing the asphalt layer from directly contacting tires of automobiles. As such, the tires of the automobiles passing through the patch 100 may be prevented from sticking the patch 100 and sliding.
In an exemplary embodiment of the present disclosure, the crushed stone layer 140 may include crushed stones each having a particle size in a range of 1.18 to 4.75 mm, for example, the crushed stones may have a single particle size of 1.18 mm, 2.36 mm or 4.75 mm. The crushed stone layer 140 may be formed by scattering an aggregate (e.g., the crushed stones) having a particle size of, for example, 2.36 mm, on the first bonding surface 111 of the first asphalt layer 110. In particular, after calendaring-molding the first asphalt layer 110, the textile layer 130 and the second asphalt layer 120 and before cooling down the same, a certain amount of crushed stones having a certain particle size may be scattered on the first bonding surface 111 of the first asphalt layer 110 uniformly using a crushed stone spreader, the crushed stones on the first bonding surface 111 of the first asphalt layer 110 are tamped to ensure bonding between the crushed stones and the first bonding surface 111, and unnecessary, redundant crushed stones on the first bonding surface 111 of the first asphalt layer 110 are removed. However, the present disclosure is not limited thereto.
In exemplary embodiments of the present disclosure, the crushed stone layer 140 may have a coverage rate of 75% to 95% on the first bonding surface 111 of the first asphalt layer 110. If the coverage rate of the crushed stone layer 140 on the first bonding surface 111 of the first asphalt layer 110 is less than 75%, the tires of the automobiles passing through the patch 100 may not be prevented from sticking the patch 100 and sliding. If the coverage rate of the crushed stone layer 140 on the first bonding surface 111 of the first asphalt layer 110 is more than 95%, travelling comfort may be negatively affected when the automobiles pass through the patch 100.
Moreover, the aggregate for forming the crushed stone layer 140 may have following technical parameters.

TABLE 3

technical parameters of the aggregate
for forming the crushed stone layer

Standard

			Second-class
		First-class	roads or	Measure-
Item	Unit	roads	lower	ment

Crushing value of stones	%	≦26	≦28	T0316
Los Angeles abrasion rate	%	≦28	≦30	T0317
Polished stone value		≧42	≧40	T0321
Apparent relative density		≧2.60	≧2.50	T0304
Water absorption rate	%	≦2.0	≦3.0	T0304
Robustness	%	≦12	≦12	T0314
Needle sheet content	%	≦15	≦18	T0312
Content of particle having	%	≦1	≦1	T0310
particle size <0.075 mm
measured by water-
washing method
Content of soft stone	%	≦3	≦5

The crushed stone layer 140 may have a thickness in a range of 1 to 5 mm. If the thickness of the crushed stone layer 140 is too thin, the tires of the automobiles may not be prevented from sticking the patch 100 and sliding. If the thickness of the crushed stone layer 140 is too thick, the entire thickness of the patch 100 and the flatness of the asphalt pavement may be negatively affected.
The release layer 150 is positioned on and covers the fourth bonding surface 122 of the second asphalt layer 120, thereby protecting the second asphalt layer 120 from external environment and facilitating package and transportation of the patch 100. According to an exemplary embodiment of the present disclosure, the release layer 150 may be a polyethylene blown thin film. The release layer 150 may have a thickness equal to or less than 0.05 mm.
According to an exemplary embodiment of the present disclosure, the patch 100 may have an entire thickness in a range of 5 to 8.5 mm. The thickness of the patch on the asphalt pavement may be in a range of 3 to 4.5 mm after the patch is compacted by the automobiles, and thus flatness of the asphalt pavement is not negatively affected.
A pothole of an asphalt pavement may be repaired quickly by using the patch according to the present disclosure. Moreover, the patch according to the present disclosure may not pollute environment around roads.
Hereinafter, a method for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure will be described.
In a method for repairing an asphalt pavement according to an exemplary embodiment of the present disclosure, firstly, an area of the asphalt pavement to be treated is pretreated according to distress characteristic of the asphalt pavement, and next, a patch according to an exemplary embodiment of the present disclosure is laid and tamped on the pretreated area of the asphalt pavement.
During the pretreating, appropriate treating techniques may be selected according to the distress characteristic of the asphalt pavement. For example, a curing agent may be sprayed to the area of the asphalt pavement to be treated when the distress characteristic of the area of the asphalt pavement to be treated has a partially loose state. In another case, when the distress characteristic of the area of the asphalt pavement to be treated includes a crack having a width greater than 5 mm or a depth greater than 10 mm, a sealant may be filled in the area of the asphalt pavement to be treated so as to seal the crack. Then, an adhesive is applied on the area of the asphalt pavement to be treated in order to facilitate bonding between the patch to be laid and the asphalt pavement.
In an exemplary embodiment of the present disclosure, the used curing agent may be formed of a material which is curable at ambient temperature in presence of water and of which curing time is less than 15 min. For example, the curing agent may include epoxy, acrylic acid or the like. The used sealant may be a heating-type asphalt-based sealant which conforms to requirements of Industry Standard JT/T740 regulated by China Transportation Department. The used adhesive may be formed of a material which is adhesive at ambient temperature in presence of water. For example, the adhesive may include epoxy asphalt, modified emulsified asphalt or the like.
The patch used in the laying and the tamping includes the structure of the patch 100 as described above, and thus the detailed structure of the patch is not described herein.
In particular, firstly, the release layer 150 of the patch 100 is peeled off such that the fourth bonding surface 122 of the second asphalt layer 120 of the patch 100 directly contacts the pretreated area of the asphalt pavement, and then, the patch 100 is tamped, for example, 3-5 times, using a rubber hammer so that the fourth bonding surface 122 of the second asphalt layer 120 is bonded to the pretreated area of the asphalt pavement, thereby completing the repairing.
The potholes of the asphalt pavement may be repaired quickly using method according to the present disclosure, for example, it takes about 15 min to repair 1 m²of pothole by using the repairing method according to the present disclosure. Thus, the method according to the present disclosure has process efficiency substantially higher than that of a conventional repairing method. Moreover, the method according to the present disclosure has advantages such as simple processes, small impact on the traffic, or the like. Moreover, there is no energy consumption, no emission, or no waste material while performing the method according to the present disclosure, and thus the method has significant application value.
While preferred implementations of the present disclosure have been described above in detail, the present disclosure is not limited to the details in the above implementations. Within the scope of the technical concept of the present disclosure, various modifications and combinations may be made to the disclosed technical solutions, and each of these modifications and combinations falls within the scope of the present disclosure.

Claims

What is claimed is:

1. A patch for repairing an asphalt pavement, comprising:

a first asphalt layer having first and second bonding surfaces opposite to each other;

a second asphalt layer having third and fourth bonding surfaces opposite to each other, the third bonding surface of the second asphalt layer facing the second bonding surface of the first asphalt layer;

a textile layer disposed between the second bonding surface of the first asphalt layer and the third bonding surface of the second asphalt layer; and

a crushed stone layer disposed on the first bonding surface of the first asphalt layer.

2. The patch of claim 1, further comprising a release layer disposed on and covering the fourth bonding surface of the second asphalt layer.

3. The patch of claim 1, wherein the textile layer includes an alkali-resistant glass fiber mesh or a basalt fiber bidirectional cloth.

4. The patch of claim 1, wherein the textile layer has a thickness in a range of 1 to 2.5 mm, and the first asphalt layer, the second asphalt layer and the textile layer have an entire thickness in a range of 2 to 4.5 mm.

5. The patch of claim 1, wherein the crushed stone layer includes crushed stones each having a particle size in a range of 1.18 to 4.75 mm, and has a coverage rate of 75% to 95% on the first bonding surface of the first asphalt layer.

6. The patch of claim 1, wherein the crushed stone layer has a thickness in a range of 1 to 5 mm.

7. The patch of claim 1, wherein the release layer includes a polyethylene blown thin film, and has a thickness equal to or less than 0.05 mm.

8. The patch of claim 2, wherein the patch has a thickness in a range of 5 to 8.5 mm.

9. A method for repairing an asphalt pavement, comprising:

pretreating an area of the asphalt pavement to be treated, according to distress characteristic of the asphalt pavement; and

laying a patch on the pretreated area of the asphalt pavement, and tamping the patch, wherein the patch comprises:

10. The method of claim 9, wherein the pretreating comprises:

spraying a curing agent to the area of the asphalt pavement to be treated when the distress characteristic of the area of the asphalt pavement to be treated has a partially loose state, or filling the area of the asphalt pavement to be treated with a sealant when the distress characteristic of the area of the asphalt pavement to be treated includes a crack having a width greater than 5 mm or a depth greater than 10 mm; and

applying an adhesive on the area of the asphalt pavement to be treated.