JP3076967B2 - Construction method of surface finishing layer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for applying a thin surface finishing layer, in which an adhesive is sprinkled on a road surface and paving materials are spread immediately thereafter.

[0002]

2. Description of the Related Art The applicant of the present invention pays attention to the distribution ratio of asphalt between an adhesive layer and a pavement layer and the overall working speed when the adhesive is sprayed on a road surface and the pavement is spread immediately thereafter. A method and an apparatus suitable for carrying it out have been proposed (EP-A-49,260).

[0003]

SUMMARY OF THE INVENTION The present invention relates to an improvement in the above-mentioned construction method, and relates to an improvement in the practical use of a thin surface finishing layer having a thickness of about 25 mm or less, which is equivalent to a surface finishing layer having a general thickness. An object of the present invention is to provide a method for efficiently and economically applying a surface finishing layer exhibiting characteristics in a short time. Especially the present invention
Has excellent surface drainage and adhesion, and impervious as a pavement
Of the surface finishing layer which is also excellent in running noise reduction effect
Is to provide a law.

[0004]

According to the present invention, when a liquid adhesive is sprayed on a road surface, a paving material is spread thereon, and a surface finishing layer is applied, a series of these operations are substantially the same. While performing continuously at intervals, using an asphalt emulsion as an adhesive, using an asphalt mixture of open grain type as a paving material, while the mixture is in a softened state, the adhesive is maintained in a liquid or softened state While
Bonding material for paving material to be laid for evaporation residue of sprayed adhesive
Ratio of 10 to 60% and the residual adhesive after spraying
Spread so that the amount becomes 0.3 to 1.2 kg / m ² ,
High adhesion with surface drainage characterized by controlling the spread of the surface finishing layer so that the finished thickness of the surface finishing layer is within 2.5 times the maximum particle size of the aggregate constituting the pavement material.
This is the method of applying the surface finish layer.

An embodiment of the method according to the invention is shown with reference to the accompanying drawings. The accompanying drawing is a schematic side view of an apparatus suitable for performing the method of the present invention.

The paving machine 1 is self-propelled, has a frame 2 mounted on several axles 3, and is equipped with the following members from the front to the rear.

A horizontal lateral push roller 4 = presses the tires of the vehicle for paving material supply; a hopper 5 for paving material; a cab 6; a paving material storage room 7; an emulsion tank 8. An emulsion spraying device 9, the spraying width of which can be adjusted in the vehicle width direction by means of a sliding structure, which spraying device is provided with a series of nozzles, each nozzle being for example a manual control or a blockage detector (not shown); A) a deocclusion needle connected to an actuating means (not shown) under the control of (2); two feed screw spreaders 10 for laterally spreading the pavement; and Vibrating finishing screed 1 that can be raised and lowered supported on a frame by arm 12
One.

For transporting the paving material, a first supply screw conveyor 13 is provided which is surrounded by a cylindrical casing 14 and has a shaft extending upward from the bottom of the hopper 5 and at the upper end thereof, a storage room. Looking inside 7. The second horizontal supply screw 15 extends to the chute 16 over the entire length of the bottom of the storage room 7 at the intermediate portion. This chute 16 discharges the paving material towards the diffusion screw spreader 10.

Further, as shown, a supply screw 17 for leveling can be provided in the storage chamber 7.

A generator 18 is also shown schematically in the drawing, which comprises a heater (not shown) for heating the pavement in the storage compartment 7, the emulsion tank 8, and the supply screws 13,15.
And 17 are powered.

The pavement finishing will be described below. This is performed by the machine 1 in a single pass (single pass) type at a high speed, and has a thickness of about 25 mm or less, and more generally, a bone used for paving material. An extremely thin surface finish having a thickness of no more than 2.5 times the maximum grain size of the material is obtained. Since such a surface finishing layer is an open-grain asphalt mixture, it maintains functions such as surface drainage, high adhesion, water impermeability and running noise reduction for a long period of time. Although the main application of the method of the present invention is the restoration of pavement function by road repair, the method of the present invention can also be used for surface finishing layers of new roads. This facing layer can be used for all types of road traffic.

Since the surface finish according to the invention is very thin, it requires a support having a proper pavement structure. The surface of the support is preferably clean, and it is desirable to remove dust and foreign matter prior to construction.

During operation of the paving machine, the machine may
m / min, preferably at a constant speed of 20-30 m / min,
It advances in the direction of arrow F in the drawing. A series of paving material supply vehicle (dump truck) (not shown) throws high-temperature paving material having a temperature of 160 ° C to 180 ° C into the hopper 5. The vehicle to supply these paving materials is a push roller 4
Being pushed by.

A screw 13 transports these paving materials into the storage compartment 7, from which the paving material is removed by screws 15
To the right chute 16 which conveys the paving material to a location in front of the inner end of the screw spreader 10. The screw spreader 10 spreads and spreads the paving material in the lateral direction. Then, it is compacted flat by the finishing screed 11. When a large accumulation of paving material occurs in the storage room 7, leveling is performed by the screw 17.

Immediately before the lower end of the chute 16,
Emulsion spraying device 9, which receives asphalt emulsion from tank 8, sprays the emulsion in nozzles over the entire width to be surface-finished, forming an adhesive layer behind the rear wheel of the machine. . Taking into account the advance speed of the machine, it is desirable to start spreading the paving material within 5 seconds after the application of the adhesive and the application. The hot paving material comes into contact with the sprayed decomposing emulsion, and the rapid rise in temperature promotes the decomposition of the emulsion. This ensures early bonding of the adhesive.

The metering of the adhesive depends on the surface condition and the porosity of the lower road surface, which varies between 0.3 and 1.2 kg / m ² as the residue of evaporation of the adhesive. This amount is higher than usual. Usually it does not exceed the 0.6 l / m ² since 0.3 kg / m ² at maximum of 50% strength. By using such a large amount of adhesive, the open particle size mixture can be strongly fixed.

The surface finish is completed by a compaction operation by a compaction machine.

Each component used in the method of the present invention will be described in detail below. As the adhesive according to the present invention, essentially any adhesive material conventionally known for pavement can be used, and an asphalt emulsion in which asphalt is emulsified and dispersed in water containing a surfactant is preferably used.

The asphalt emulsion may be modified by adding a rubber or an elastomer in order to enhance the adhesive strength and the like.
For example, a modified asphalt emulsion modified with at least 3% of latex or SBS copolymer is particularly preferably used.

The asphalt emulsion preferably has an evaporation residue obtained by evaporating water in the emulsion of 60% or more. High concentrations of asphalt emulsions can promote water evaporation and decomposition of the sprayed emulsion. If the concentration is extremely high, workability will be impaired.
Is preferably used.

In the present invention, the asphalt emulsion is generally preferably used in a larger amount, for example, about twice or more than when the asphalt emulsion is used as an adhesive. The asphalt emulsion has a softening point of 50 ° C. or more, especially 60 ° C.
It is preferable that the temperature is not lower than ° C. This is higher than the softening point of commonly used asphalt emulsions. In the present invention, in order to spray a large amount of asphalt emulsion as described above,
If the road surface temperature exceeds 50 ° C after construction,
° C, by increasing the softening point, softening of the asphalt emulsion evaporation residue as the adhesive layer,
Outflow can be prevented. When the asphalt emulsion is heated to 50 to 85 ° C. and used, the higher the softening point, the better the stability of the asphalt particles dispersed in the spraying device such as a nozzle and a pipe against mutual adhesion and deformation. Excellent.

The asphalt emulsion is preferably used by heating, and the heating temperature is preferably 50 ° C. or higher, more preferably 70 to 85 ° C. By heating, the water evaporation and decomposition of the sprayed asphalt emulsion can be promoted, and the adhesion between the existing road surface and the pavement material can be enhanced. Heating also lowers the viscosity of the emulsion,
Spreading is facilitated, and the adhesion is improved by heating the road surface or suppressing the temperature drop of the pavement material. On the other hand, when the heating temperature is 85 ° C. or higher, depending on the type of emulsion, it may be partially decomposed and deteriorated during storage, or a mass of asphalt may be generated to cause clogging in a spraying device such as a pipe.

As an example of the asphalt used for producing the asphalt emulsion according to the present invention, 80/100, 180/2 conforming to the French asphalt standard for pavement.
Table 1 shows the properties of each of the 20 asphalts.

[0024]

[Table 1]

Table 2 shows an example of the asphalt emulsion used in the present invention.

[0026]

[Table 2]

The amount of the asphalt emulsion to be sprayed is determined by the ratio of the evaporation residue of the sprayed emulsion to the binder of the laid pavement is 10%.
~ 60% and the emulsion evaporation residue is 0.3 ~ 1.2k
g / m ² , preferably 0.4 to 0.7.
More preferably, it is in the range of kg / m ² . The amount of application differs depending on the type of pavement material and the condition of the road surface. If the amount is less than this range, the desired effect cannot be obtained, and if the amount is too large, problems such as runoff will occur. For example, if the road surface is smooth, the application amount is reduced, and if the road surface is rough, adjustment is made such as increasing the application amount.

The asphalt mixture of the open particle size type used as a pavement material in the present invention is a mixture containing at least an aggregate and a binder, and the binder remains in a softened state until the rolling operation is completed. I need to do that. A pavement material that does not satisfy these requirements cannot exhibit the excellent effects of the present invention, including strong adhesion to an asphalt emulsion used as an adhesive.

The aggregate used for the open-grain type asphalt mixture is usually composed of coarse aggregate such as crushed stone and gravel, and fine aggregate such as natural sand and screenings. More preferably, the maximum particle size of the aggregate is in the range of 5 to 13 mm.

As an example of the coarse aggregate used, Table 3 shows the aggregate particle size of each of 4/6, 6/10 and 6/12 according to the French crushed stone standard. Table 4 shows an example of the properties of the preferably used coarse aggregate.

[0031]

[Table 3]

[0032]

[Table 4]

Table 5 shows an example of the aggregate particle size of the fine aggregate used.
Shown in When the fine aggregate is screenings, the sand equivalent according to the French standard NFP18-598 is preferably greater than 60.

[0034]

[Table 5]

The open particle type asphalt mixture includes:
For the purpose of adjusting the synthetic particle size and increasing the mechanical strength of the mixture, fillers such as stone powder, slaked lime, fly ash, collected dust, fillers such as cement, and fillers such as mineral fibers and plant fibers are added as necessary. No problem.

When the fine aggregate does not sufficiently contain fine particles of 80 μm or less, it is desirable to add a filler as a filler. The amount of the filler passing through the 0.15 mm sieve is 90 to 100 wt%, and the amount of the 75 μm sieve passing through the filler is 8%.
It is desirable to set it to 0 wt%.

As the binder of the asphalt mixture of the open particle size type, asphalt for pavement as described in the Asphalt Pavement Outline issued by the Japan Road Association is used. For example, in addition to straight asphalt, in order to prevent the mixture from scattering or flowing, and to prevent the binder from sagging, modified I-type or modified II-type modified with rubber or elastomer, or 60%
High-viscosity modified asphalt having improved viscosity at ℃, toughness, tenacity, etc. is used. The amount of binder added
3.0 to 6.0 wt based on the weight of aggregate and filler
%.

Although the binder is also affected by weather conditions and traffic volume, as an example of asphalt to be used, 80/100, 60/80 in conformity with NFT66-004 and NFT66-008, which are French asphalt standards for pavement.
70 are shown in Table 6.

[0039]

[Table 6]

In order to impart the desired function to the finished pavement, the pavement obtained by compacting the asphalt mixture of the open particle size type has a porosity of 15% or more, more preferably 2% or more.
Desirably, it is 0% or more. Therefore, the aggregate composition of the asphalt mixture of the open particle size type requires 35 watts of the 2.36 mm sieve passing through the synthetic particle size including the filler.
It is desirable that the content be in the range of t% or less, preferably 25 wt% or less, more preferably 10 to 20 wt%.

Table 7 shows an example of the synthetic particle size of the aggregate and the filler of the asphalt mixture of the open particle size type. The optimum amount of asphalt at this time is 5.2 w
t%.

[0042]

[Table 7]

Conventional techniques can be applied to the design, manufacture and construction of the asphalt mixture of the open particle size type.
It is desirable to use the construction machine according to the present invention for spreading.

The thickness of the surface finishing layer is set at 2.5 times the maximum particle size of the aggregate constituting the pavement material in order to obtain the desired function and effect.
The spread is controlled so as to be less than twice. In the prior art, when the open-grain asphalt mixture is spread in a thin layer, dragging occurs, making it extremely difficult to construct, and even if spread, the adhesive strength to the road surface is weak, and the aggregates scatter after construction. The serviceability was remarkably poor.

According to the present invention, immediately after a large amount of the adhesive is sprayed, the asphalt mixture of the open-grain type as a pavement material is spread evenly. Therefore, the adhesion between the road surface and the pavement material is excellent, and the pavement material has a thin layer. Construction is possible. In addition, by increasing the concentration of the asphalt emulsion and heating, the decomposition of the emulsion can be promoted, and the fixability of the pavement material is improved. In addition, asphalt emulsion in the liquid state boils due to the moisture in the emulsion coming into contact with the pavement material, in which case the asphalt in the emulsion rises and penetrates into the mixture, covering the aggregate in the pavement material and softening. As a result of adhesion to certain asphalt, the adhesion area of the aggregate on the road surface and the pavement material increases, and a strong adhesion force is obtained.

Using the apparatus shown in FIG. 1, the elastomer-modified asphalt emulsion shown in Table 8 was placed in the emulsion tank 8, the open-grain type asphalt mixture shown in Table 9 was placed in the paving material storage room 7, and the above-mentioned elastomer-modified asphalt was added. The asphalt emulsion was heated to about 75 ° C. and sprayed on the road at a rate of 0.7 l / m ² , and the asphalt was heated at regular intervals to maintain a substantially dispersed liquid of the emulsion on the road. The above asphalt mixture in a softened state was continuously spread.

The finished thickness is 25 mm and the porosity is 21%. Despite the thin layer, a high quality surface finish layer could be applied without any scratching.

[0048]

[Table 8]

[0049]

[Table 9]

[Brief description of the drawings]

FIG. 1 is a side view of a road surface finishing machine used for carrying out the method of the present invention.

[Explanation of symbols]

 5 Paving Material Hopper 6 Operator's Cab 7 Paving Material Storage Room 8 Emulsion Tank 9 Emulsion Sprayer 10 Screw Spreader 11 Finishing Screed 16 Shoot

Continuation of the front page (72) Inventor Jean-Paul Faure 92190 Moudon, Lou Serviyan 2 (56) References JP-A-4-203006 (JP, A) (58) Fields investigated (Int. Cl. . ^7, DB name) E01C 19/48

Claims (8)

(57) [Claims] 1. A method in which a liquid adhesive is sprayed on a road surface, a paving material is spread thereon, and a surface finishing layer is applied. An asphalt emulsion is used as an adhesive, an asphalt mixture of an open particle size is used as a pavement material, and while the mixture is in a softened state, this is sprayed while the adhesive is in a liquid or softened state. Evaporation
The proportion of binder in the paving material to be laid is 10-60%
And the evaporation residue of the sprayed adhesive is 0.3 to 1.2k
g / m ^2, and control the spread so that the finished thickness of the surface finishing layer is within 2.5 times the maximum particle size of the aggregate constituting the paving material. A method of applying a highly adherent surface finish layer having surface drainage characteristics characterized by the following. 2. The maximum particle size of the aggregate of the paving material is 5 to 13 mm.
The method for applying a surface finishing layer according to claim 1, wherein 3. An asphalt mixture of an open particle size type
The method according to claim 1 or 2, wherein the porosity of the package is 15% or more . 4. The method according to claim 1, wherein the adhesive used has a distillation residue of 60% or more and a softening point of 50 ° C. or more. 5. The method for applying a surface finishing layer according to claim 1, wherein the spraying temperature of the adhesive used is 50 ° C. or higher. 6. The method according to claim 1, wherein the adhesive is a modified asphalt emulsion. 7. The bonding material of the paving material is a modified asphalt.
A method for applying a surface finishing layer according to any one of claims 1 to 6. 8. A series of operations are performed by running a paving material laying device.
In the direction of the adhesive
8. The method according to claim 1, wherein the treatment is performed continuously at substantially the same intervals.
The method for applying a surface finishing layer according to claim 1 .