JP3327140B2 - Method of exposing aggregate on concrete pavement - 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 of exposing aggregate on a concrete pavement surface, and more particularly, to a method of exposing a concrete pavement on a concrete pavement surface to reduce road surface noise which is considered to be higher in noise than asphalt pavement. It relates to the method of exposing materials.

[0002]

2. Description of the Related Art It has been known that tire / road noise generated when a vehicle tire passes over a pavement surface is higher on concrete pavement than on asphalt pavement. It is a bottleneck when applying concrete pavement.

[0003] On the other hand, it has been found that the tire / road surface noise can be considerably reduced by optimizing the surface shape of the concrete pavement surface. Attempts are being made to finish or to cast porous concrete on the surface layer.

[0004] Among them, the method of exposing the aggregate is such that the mortar on the surface of concrete forming the surface layer of the pavement is cut out to form an exposed surface of the aggregate having a desired texture depth. , To reduce tire / road noise.

[0005] In addition, even with such an aggregate exposing method,
As coarse aggregate of concrete constituting the surface layer, 10
The so-called small particle size aggregate exposing method using a small particle size coarse aggregate having a particle size of not more than 8 mm is excellent in low noise performance, and preferably uses a coarse aggregate having a particle size of 8 mm or less. Stuff and more preferably high quality size 8/4
Concrete using single-grain crushed stone having a small particle size of mm as a coarse aggregate is also employed.

[0006] As a method for shaving the mortar on the pavement surface from the concrete constituting the surface layer, high-pressure water is generally sprayed on the concrete surface, which is known as a green cut method. And a method of shaving the mortar on the surface with a brushing machine equipped with a wire brush.

[0007]

However, in the above-described method using the green cutting method or the brushing machine, it is necessary to cut the concrete before it is completely hardened at an appropriate timing. Therefore, it is not easy to manage the timing, and the construction accuracy may be influenced by the season, temperature, weather, and the like.

On the other hand, after the concrete of the surface layer is poured, a layer of a setting retarder called a retarder for delaying the setting reaction of cement is formed on the surface thereof, so that the hardening of the mortar on the surface is delayed. Adjustment, thereby adjusting the time to perform the shaving work, while a method of extending the period during which the shaving work is possible has been adopted, but according to such a method, the setting retarder used for this is Since it is easily eluted in water, there has been a problem that it takes time and effort to manage the function effectively.

That is, for example, it is necessary to lay a curing sheet such as a vinyl sheet over the setting retarder layer in order to prevent elution due to rainwater or water sprinkling, but the entire pavement surface having a large area is required. The work of laying such a curing sheet is a complicated work, and the curing sheet is easily turned up by wind and the like. There was a problem that laying work became difficult.

[0010] In addition, from the hardened concrete spread on the surface layer portion, usually, the breathing water as surplus water in the concrete leaches out on the surface thereof. Due to such breathing water, the setting retarder on the concrete surface elutes or flows out, and there is a problem that its function cannot be exhibited effectively.

Accordingly, the present invention has been made in view of such conventional problems, and delays the progress of the cement setting reaction without being greatly affected by weather such as rainy weather, thereby reducing the aggregate. The purpose of the present invention is to provide a method of exposing aggregate on a concrete pavement surface, which can easily perform a work of shaving a mortar portion for exposing a mortar, thereby easily obtaining an exposed surface having a uniform texture depth. Is what you do.

Further, the present invention provides a work for delaying the progress of the setting reaction of cement without being affected by the breathing water leached from the concrete constituting the surface layer, and shaving the mortar for exposing the aggregate. It is an object of the present invention to provide a method for exposing aggregate on a concrete pavement surface, whereby an exposed surface having a uniform texture depth can be easily obtained.

[0013]

SUMMARY OF THE INVENTION The present invention has been made to achieve the above-mentioned object, and the gist of the invention is to spread concrete forming a surface layer of a pavement, and then to lay the surface of the concrete with water. It does not dissolve in water, it is hydrolyzed in alkaline water and covered with a setting retarder to express the setting retardation of cement, and after the aging period, the mortar on the surface is cut out to expose the aggregate. So,
The setting retarder is added to a constitutive material constituting a surface layer of the pavement.
Greater than the specific gravity of breathing water leached from cleats
A method of exposing aggregate on a concrete pavement surface in which the surface of concrete is adhered by being scattered or scattered as a coating type or powder type having a high specific gravity, and Wherein the coarse aggregate of concrete is a small-grain coarse aggregate having a particle size of 10 mm or less.

As the setting retarders which are not dissolved in water but are hydrolyzed in alkaline water to exhibit the setting retardation of cement, various retarders having such properties can be used. Preferably, an unsaturated polyester having a glycol and a dibasic acid as main components and a weight average molecular weight of 300 to 25,000,
1 to 5 parts per 100 parts by weight of the unsaturated polyester
A setting retarder obtained by crosslinking with 0 parts by weight of a styrene-based monomer can be used.

The above-mentioned setting retarder containing glycol and dibasic acid as main components serves as a binder for water-soluble setting retarders such as lignin, oxycarboxylic acid and sodium gluconate. Since it has a function of suppressing the dissolution of a water-soluble setting retarder, by using such a water-soluble setting retarder mixed with the above-described setting retarder containing glycol and a dibasic acid as main components, It can be used as a setting retarder that does not dissolve in water but hydrolyzes in alkaline water to develop the setting retardation of cement.

The unsaturated polyester glycol is mainly composed of a dihydric alcohol such as ethylene glycol or propylene glycol or a polyoxyalkylene glycol which is a polymer thereof, and this glycol is 50 to 100% by weight based on the weight of the glycol component. Is preferable.

The styrenic monomer is added as a crosslinking component for curing the unsaturated polyester, which is often oily, and improves the mechanical properties of the unsaturated polyester as a resin.
It is added for the purpose of controlling water resistance as a retarder, and besides this, for example, methyl acrylate,
Ethyl acrylate, butyl acrylate, alkyl acrylate, hydroxyethyl acrylate, and methacrylates thereof can be used, and one or more of them can be used as a polymerization monomer.

Further, when the unsaturated polyester resin is cured, it is carried out by polymerizing styrene with a radical initiator such as an organic peroxide and at the same time crosslinking the unsaturated polyester resin with the unsaturated polyester. However, in order to cure in a short time of about 1 hour or less, it may be performed under a temperature condition of about 60 to 200 ° C.
In order to further promote crosslinking, a curing accelerator such as an organic acid salt of cobalt can be used in combination.

According to the setting retarder, when the weight average molecular weight of the unsaturated polyester is less than 300, the setting retarding effect is reduced. When the weight average molecular weight of the unsaturated polyester is more than 25,000, the melt viscosity is increased. The addition of styrene-based monomers described below becomes difficult due to an increase in the content of styrene-based monomers, and neither is preferred.

When the amount of the styrene monomer added to the unsaturated polyester is less than 1 part by weight based on 100 parts by weight of the unsaturated polyester, the mechanical properties and water resistance of the unsaturated polester are insufficiently improved. If the amount is more than 50 parts by weight with respect to 100 parts by weight of the unsaturated polyester, the retarding effect of the setting retarder becomes insufficient.

According to the method for exposing aggregate of the present invention, a coating-type or powder-type setting retarder is applied to the surface of concrete, for example, by using various known dispersing devices or dispersing devices. If set or sprayed out with a uniform thickness of about 0.01 to 10 mm, these setting retarders will cover and easily adhere to the surface of concrete even if the surface of the concrete has irregularities. .

According to the coating type setting retarder,
For example, the setting retarder itself easily adheres to the surface of the concrete by its own weight, and according to the powder type setting retarder, it easily adheres to the surface of the concrete via, for example, water existing on the surface of the concrete. Will adhere to.

According to the method for exposing aggregate on a concrete pavement surface of the present invention, since the setting retarder has a property of not dissolving in water, the setting retarder may be eluted by rainwater or the like. Absent.

Also, the unsaturated polyester resin constituting the setting retarder, for example, an unsaturated polyester resin is hydrolyzed by an alkali contained in the cement to form a polyester oligomer and further a glycol and a dibasic acid. In addition to suppressing the reaction, the decomposition products generated by the hydrolysis are adsorbed on the surface of the cement particles, so that the effect of suppressing the hydration reaction of the cement is maintained for a long time. Even for concrete pavements that have been cured for a long period of 28 days, the mortar on the surface can be easily cut off.

That is, according to the present invention, after the concrete forming the surface layer of the pavement is spread, the coating type or powder type setting retarder having the above properties is applied to the surface of the concrete. For example, 0.01 to
If it is scattered or scattered in a layer of about 10 mm, preferably about 0.2 mm, these setting retarders cover and adhere to the concrete surface, without the use of a curing sheet, and are affected by the weather and the like such as rainy weather. Without any particular delay, the progress of the cement setting reaction is delayed, thereby facilitating the work of shaving the mortar for exposing the aggregate and easily obtaining a concrete pavement surface having a uniform texture depth. Becomes possible.

Further, the method for exposing aggregate according to the present invention is a concrete pavement in a so-called small-grain aggregate exposing method using coarse aggregate having a particle size of 10 mm or less as a coarse aggregate of concrete constituting a surface layer portion. Since it is adopted for the surface, in particular, it is possible to easily secure a uniform exposed surface having a texture depth of about 1 mm, and to easily obtain a concrete pavement surface having further excellent noise reduction.

Further, in the method for exposing aggregate of the present invention, the specific gravity of the breathing water leached from the concrete constituting the surface layer of the pavement is at least as the setting retarder of the coating type or the powder type. It is preferable to use one having specific gravity.

Here, as a method of increasing the specific gravity of the setting retarder, for example, it is conceivable to increase the specific gravity of such a setting retarder itself.

As another method for increasing the specific gravity of the setting retarder, for example, a method of mixing such a setting retarder with sand or coating the sand is considered. To coat the setting retarder on sand, for example, add sand and setting retarder to a sieve and apply vibration.In the case of a coating-type setting retarder, it adheres to the sand particles due to its adhesiveness. By coating, or in the case of a powder type setting retarder, by adhering to the sand particles via moisture or the like, the coating is easily performed.

That is, the setting retarder mixed with the sand or coated on the sand in this manner moves integrally with the sand particles, and thus has an apparent higher specific gravity.

If the coating type or powder type setting retarder has a specific gravity larger than the specific gravity of the breathing water leached from the concrete constituting the surface layer of the pavement as described above, Even if breathing water leaches out of concrete after the concrete of the surface layer is spread and the set retarder is adhered to the surface, even if the breathing water is leached out of the concrete, the set retarder has a large specific gravity and does not float on the concrete surface without rising in the breathing water. , And is prevented from flowing out by breathing water.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention, ie, an embodiment, will be described below in detail with reference to the accompanying drawings. According to this embodiment, in a so-called small particle size aggregate exposing method for concrete pavement, a particle size of 10 mm or less, preferably 8 m, constituting a surface layer portion.
high quality size 8 as coarse aggregate with a particle size of
After concrete containing / 4 mm small grain crushed stone is hardened, mortar is cut out from the surface of this concrete,
In order to secure a uniform exposed surface having a texture depth of about 1 mm on the pavement surface, the method for exposing aggregate on a concrete pavement surface of the present invention is employed.

That is, the concrete pavement surface formed by such a small particle size aggregate exposure method can reduce tire / road surface noise such as air pumping noise and have a noise level equal to or higher than that of the asphalt pavement surface. Become.

According to this embodiment, as shown in FIG. 1, above the lower concrete 10 cast and formed by ordinary concrete, the small concrete of the size of 8/4 mm is formed as the concrete constituting the surface layer. The small-grain aggregate-mixed concrete 11 made of single-grain crushed stone is used as a coarse aggregate, for example, is spread to a thickness of about 4 cm and is compacted.

It should be noted that such small-grain aggregate-mixed concrete 11 does not necessarily need to be cast only on the surface layer. It can also be constituted by concrete 11.

Then, after the small-grain aggregate-mixed concrete 11 of the surface layer is spread and laid, the surface thereof is not dissolved in water but hydrolyzed with alkaline water,
As a setting retarder that expresses the setting retardation of cement,
Setting retardation obtained by crosslinking an unsaturated polyester having a glycol and a dibasic acid as main components and a weight average molecular weight of 300 to 25,000, with 1 to 50 parts by weight of a styrene monomer based on 100 parts by weight of the unsaturated polyester. An operation of covering with the agent 12 is performed.

Here, the coating type setting retarder 12 adheres to the sand particles by being coated on the sand, whereby the apparent specific gravity is reduced by the small particle size aggregate. It is larger than the specific gravity of the breathing water leached from the concrete 11.

When such a setting retarder 12 of the coating type coated on sand is sprayed on the surface of concrete with a uniform thickness of, for example, about 0.01 to 10 mm by using a spraying apparatus, the setting is performed. The retarder 12 covers the surface of the small-grained-aggregate-mixed concrete 11 and easily adheres to the surface of the concrete 11 even if there is unevenness on the surface of the concrete 11.

While the surface is covered with the setting retarder 12 in this manner, the small-grain aggregate-mixed concrete 11 is cured for a predetermined period. includes a not soluble nature, with never be <br/> Therefore eluted like rainwater, it is possible to perform the curing work without any particular installation the curing sheets for rainwater countermeasures.

The setting retarder 12 which adheres to the surface of the small-grain aggregate-mixed concrete 11 has a large specific gravity even if the breathing water 13 leaches out of the concrete 11 due to its large specific gravity.
This allows the breathing water 13 to pass therethrough without being lifted inside, keeps the close contact with the surface of the concrete 11, and prevents the water from flowing out together with the breathing water 13.

Further, the setting retarder 12 comes into contact with the concrete 11 on the surface and hydrolyzes with alkaline water,
This suppresses the hydration reaction of cement,
Since the suppression effect can be maintained for a long period of time, the start time of the work for cutting out the mortar on the surface is not particularly limited, and for example, a small particle size after a long-term curing of 28 days of material age It is also possible to easily perform the surface treatment on the aggregate-mixed concrete 11.

Then, after the spread small-grain aggregate-mixed concrete 11 has been cured for a predetermined period of time, an operation of shaving mortar from the surface thereof is performed.

That is, such a shaving operation is performed by a green cut method for washing the mortar by spraying high-pressure water, a method for shaving the mortar on the surface by a brushing machine equipped with a wire brush, or the like. However, the hardening reaction of the mortar is delayed due to the effect of the setting retarder 12 on inhibiting the hydration reaction of the cement. Since the agent 12 was in close contact with the surface of the small-grain aggregate-mixed concrete 11 and suppressed the hydration reaction of cement, the pavement surface after shaving such mortar had a texture depth of 1 mm. An exposed surface of a uniform degree can be easily secured.

Therefore, by having such an exposed surface, tire / road surface noise such as air pumping noise is reduced, and concrete pavement excellent in low noise is formed.

The present invention is not limited to the embodiment of the above embodiment, but may be variously modified and adopted within the scope of the constitution described in each claim. For example, the setting retarder does not necessarily need to be used as a coating type, but can also be used as a powder type.By increasing the specific gravity of the setting retarder itself, the setting retarder can be used. Can also be increased.

EXPERIMENTAL EXAMPLE An unsaturated polyester containing glycol and a dibasic acid as main components and having a weight-average molecular weight of 300 to 25,000 was mixed with 1 to 50 parts by weight of a styrene monomer based on 100 parts by weight of the unsaturated polyester. By setting 50 mg of a setting retarder composed of a crosslinked product in a sheet shape having a thickness of about 0.1 mm, immersing each in water and alkaline water having a pH of 13 at room temperature, taking out the samples every hour, and measuring the weight thereof, The elution amount was determined. Table 1 shows the test results.

[0047]

[Table 1] The above test results show that the setting retarder does not dissolve in water, but readily elutes in alkaline water having a pH of 13.

[0048]

As described in detail above, the method for exposing aggregate in concrete pavement according to the present invention involves hydrolyzing the spread concrete surface with alkaline water without dissolving it in water. Expressing the retardation of setting of cement, covered with a coating-type or powder-type setting retarder, and after the curing period has passed, it is formed by cutting out the mortar on the surface and exposing the aggregate, Can easily adhere to the surface of concrete, delay the progress of cement setting reaction without being affected much by weather such as rain, etc., and cut out the mortar for exposing aggregate The work can be performed easily, and a concrete pavement having an exposed surface with a uniform texture depth can be easily obtained.

Further, if a coating type or powder type setting retarder having a specific gravity higher than the specific gravity of the breathing water leached from the concrete forming the surface layer of the pavement is used, the breathing water is reduced from the concrete. Even when leaching, the setting retarder, due to its large specific gravity, can easily maintain its close contact with the concrete surface without floating in the breathing water, and can be easily prevented from flowing out by the breathing water. become.

[0050] Further, particularly concrete constituting the surface layer portion is a concrete blended with small particle径粗aggregates particle size of less than 10 mm, on the pavement, texture depth 1mm
It is possible to easily secure a uniform exposed surface to a certain degree, and to easily form a concrete pavement having even lower noise.

[Brief description of the drawings]

[Fig. 1] The concrete surface of the surface layer
FIG. 4 is a cross-sectional view showing a situation where the cement is not dissolved in water but is hydrolyzed in alkaline water to be coated with a coating-type setting retarder that develops a setting retardation property of cement.

[Explanation of symbols]

Reference Signs List 10 lower layer concrete 11 small particle size aggregate-mixed concrete (surface layer concrete) 12 setting retarder

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) E01C 7/14 E01C 7/32

Claims (4)

(57) [Claims] After the concrete constituting the surface layer of the pavement is spread and leveled, the surface of the concrete is not dissolved in water but is hydrolyzed with alkaline water to cause the cement to retard the setting of the cement. A method of covering the surface with a retarder and, after the curing period, extruding the mortar on the surface to expose the aggregate, wherein the setting retarder is used for the pavement.
Bridge leaching from the concrete that makes up the surface
A method of exposing aggregate on a concrete pavement surface in which the surface of concrete is adhered by spraying or spraying as a coating type or a powder type having a specific gravity larger than the specific gravity of the water for coating. A method for exposing aggregate on a concrete pavement surface, wherein the coarse aggregate of concrete forming the surface layer of the pavement is a small-grain coarse aggregate having a particle size of 10 mm or less. 2. The setting retarder comprises glycol and a dibasic acid as main components, and has a weight average molecular weight of 300 to 2500.
0 unsaturated polyester, this unsaturated polyester 1
The method for exposing aggregate on a concrete pavement surface according to claim 1, wherein the aggregate is crosslinked with 1 to 50 parts by weight of a styrene-based monomer with respect to 00 parts by weight. 3. A retarder having a specific gravity greater than the specific gravity of the breathing water, concrete according to claim 1 or claim 2, characterized in that it consists of one raised the specific gravity of itself the retarder Method of exposing aggregate on pavement surface. 4. A retarder having a specific gravity greater than the specific gravity of the breathing water, is sand and mixed, or that consisting of those obtained by coating sand according to claim 1 or claim 2, wherein Method of exposing aggregate on concrete pavement surface.