JPH10252006A - In-situ placing water-permeable concrete pavement - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-permeable concrete pavement having a flexural strength of 5.5N/mm<2> or more and a permeability coefficient of 0.1cm/sec or more, such that the degree of peeling of raw aggregate in its surface part due to passage of vehicles is small. SOLUTION: A concrete pavement is constructed by laying an admixture of raw aggregate and a composition comprising paste or mortar whose volume ratio to 100% of the aggregate is 30-80%. In that case, the paste or mortar comprises cement or a cement-containing powder mixture; fine aggregate whose weight ratio to the cement or powder mixture is 0-140%; a high-performance water reducing agent whose weight ratio to the cement or powder mixture is 0.5-2.0%; a retardant whose weight ratio to the cement or powder mixture is 0.01-0.2%, or a contraction reducing agent whose weight ratio to the cement or powder mixture is 0.5-5.0%; and water whose weight ratio to the cement or powder mixture is 16-28%.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pavement-permeable permeable concrete pavement which can be used not only on sidewalks but also on roads with heavy traffic.

[0002]

2. Description of the Related Art As a prior art relating to road cast-in-place permeable concrete, for example, Japanese Patent Publication No. 5-34299.
The publication discloses that 300 to 400 kg of Portland cement per 1 m ^{3 of} cement concrete mixture, 0.005 to 0.1 parts by weight of binder and 0.35 to 0.45 parts by weight of water per 1 part by weight of the cement There is disclosed a method for constructing a water-permeable cement concrete pavement in which a cement concrete mixture having a mixing ratio of the remaining aggregate is kneaded, and the kneaded material is cast on a paved surface with a finisher.

Further, Japanese Patent Publication No. Hei 7-99002 discloses that
300 to ⁴ per m3 of cement concrete mixture
00 kg of Portland cement, 0.008 to 0.04 parts by weight of binder and 0.3 to 0.45 parts by weight of water per 1 part by weight of the cement and the balance 10:
Disclosed is a method for producing a water-permeable cement concrete structure, which comprises a step of kneading an aggregate consisting of sand and crushed stone No. 7 in a weight ratio of 90 to 15:85, flowing or casting the obtained mixture, and curing. I have. Up to now, permeable concrete pavement has been mainly used for sidewalks and the like, but application to roads is also being studied because drainage of rainwater and the like is improved.

[0004]

When permeable concrete pavement is applied to a road with heavy traffic, 5.5 is required.
A bending strength of N / mm ² or more is required. However, conventionally, a cast-in-place permeable concrete pavement having a bending strength of 5.5 N / mm ² or more and a water permeability of 0.1 cm / sec or more has not been developed.

[0005] The cement concrete pavement constructed by the method disclosed in Japanese Patent Publication No. 5-34299 and the water-permeable cement concrete structure produced by the method disclosed in Japanese Patent Publication No. 7-99002 are also used. In order to secure a water permeability of 0.1 cm / sec or more, the bending strength is 4.0 N / mm ² or less, and therefore, it cannot be applied to a road with a large traffic volume.
On the other hand, in order to increase the bending strength to 5.5 N / mm ² or more, it is necessary to sufficiently compact with a vibrating roller or the like.
Water permeability is less than 0.1 cm / sec. Therefore, development of an in-place permeable concrete pavement having a bending strength of 5.5 N / mm ² or more and a water permeability of 0.1 cm / sec or more has been desired.

On the other hand, when paving concrete, concrete is generally kneaded at a concrete factory,
The kneaded material is transported to a construction site by a dump truck and is constructed. If the construction site is located about 1 to 2 hours after kneading due to reasons such as being far from the concrete factory, the constructed pavement will be paste or mortar on the surface layer of the pavement due to traffic traffic. The coarse aggregate coated on the surface is easily peeled off. When the coarse aggregate is peeled, unevenness is generated on the pavement surface, and the serviceability deteriorates.

[0007]

Means for Solving the Problems Accordingly, the present inventors have:
5.5N / which can be applied to roads with heavy traffic
It has a bending strength of at least ² mm2 and a water permeability of 0.1 cm / sec or more, and does not cause a problem in serviceability even if it is constructed after elapse of about 1 to 2 hours after kneading. As a result of diligent research on concrete pavement, the flexural strength and hydraulic conductivity can be kept above a certain level if the mixing ratio of raw materials for concrete pavement is within a specific range and a specific amount of retarder and / or shrinkage reducing agent is added. While holding
The inventors have found that peeling of the surface layer of pavement can be greatly reduced, and have reached the present invention.

That is, the cast-in-place permeable concrete pavement according to claim 1 is a pavement composition comprising a coarse aggregate and a paste or mortar having a volume ratio of 30 to 80% with respect to 100% of the coarse aggregate. A pour-in-place permeable concrete pavement in which a kneaded material is laid, wherein a weight ratio of the paste or mortar to a powder mixture containing cement or cement and a powder mixture containing the cement or cement is 0 to 140%. The fine aggregate and the weight ratio to the cement or the powder mixture containing the cement is 0.5 to
2.0% of a high-performance water reducing agent and a weight ratio of 0.01 to 0.2% to the cement or a powder mixture containing the cement
And water having a weight ratio of 16 to 28% to the cement or the powder mixture containing the cement.

The pour-in-place permeable concrete pavement according to claim 4 is a pavement composition comprising a coarse aggregate and a paste or mortar having a volume ratio of 30 to 80% with respect to 100% of the coarse aggregate. Cast-in-place permeable concrete pavement comprising laying a kneaded material, wherein the paste or mortar is cement or a powder mixture containing cement,
A fine aggregate having a weight ratio of 0 to 140% with respect to the cement or the powder mixture containing the cement, and a weight ratio of 0.5 to 2.0 with respect to the cement or the powder mixture containing the cement;
% Of a high-performance water reducing agent, a shrinkage reducing agent having a weight ratio of 0.5 to 5.0% to the cement or a powder mixture containing the cement, and a total amount of the shrinkage reducing agent and water, 16-28 by weight relative to the powder mixture
% Of water.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As coarse aggregate used in the present invention, grains such as gravel and crushed stone having a particle size of 2.5 to 20 mm are used.

The term "powder mixture containing cement or cement" used in the present invention refers to a powder mixture composed of cement and other powder materials added as required. Examples of the cement include hydraulic cement such as ordinary Portland cement, early-strength Portland cement, moderate heat Portland cement, and white cement. Examples of other powder materials added as necessary include fly ash, blast furnace slag powder, silica fume, limestone powder, and inorganic powder such as silica stone powder.

The proportion of these other powder materials in the powder mixture containing cement is about 60% by weight or less in the powder mixture. When blast furnace slag powder is used, 50
% By weight or less. The addition of these other powder materials can improve the bending strength and the like.

Furthermore, in order to improve the bending strength, a paste or mortar to which a polymer is added may be used. Examples of the polymer include a thermoplastic resin such as an ethylene / vinyl acetate copolymer or an acrylic copolymer. The amount of addition is preferably not more than 20% by weight relative to cement or a powder mixture containing cement. In addition to these, a coloring material such as redwood may be added to improve decorativeness. The addition amount is 5 parts by weight based on the cement or the powder mixture containing the cement.
% Is preferable.

When the coarse aggregate has a particle size of 5 mm or more, the fine aggregate has a particle size of less than 5 mm, preferably 2.5 mm or less, more preferably 1 mm or less. In the case of 2.5 mm or more and less than 5 mm, the particle size is less than 2.5 mm, preferably 1.5 mm or less, more preferably 0.5 mm or less.
Any particle having a particle size distribution of not more than mm can be used. If the particle size of the fine aggregate is too close to the particle size of the coarse aggregate, it becomes difficult to coat the mortar on the coarse aggregate, which is not preferable. The types of fine aggregate include river sand, mountain sand, crushed sand, and the like.

The amount of the fine aggregate added is 0 to 140% by weight, usually about 100%, based on the cement or the powder mixture containing the cement. By adding the fine aggregate, shrinkage due to drying can be suppressed. When the amount of the fine aggregate exceeds 140%, the coating thickness of the mortar becomes thin, so that the bending strength becomes small.

Examples of the high-performance water reducing agent include naphthalenesulfonic acid-based, polycarboxylic acid-based, and melamine-based high-performance water reducing agents, and both liquid and powder can be used. The amount of the high-performance water reducing agent is 0.5 to 2.0% by weight based on the cement or the powder mixture containing the cement. When the addition amount is less than 0.5%, the coating thickness of the paste or mortar becomes thin, so that the bending strength becomes small. On the other hand, if the addition amount exceeds 2.0%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability is reduced.

Examples of the retarder include organic acids such as monocarboxylic acids, polycarboxylic acids, oxycarboxylic acids, and amino acids, and metal salts thereof such as sodium, potassium, lithium, calcium, and magnesium. Specifically, examples of monocarboxylic acids include formic acid and acetic acid, and examples of polycarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, phthalic acid, and terephthalic acid. And the like. Examples of the oxycarboxylic acid include heptonic acid, gluconic acid, glycolic acid, malic acid, tartaric acid, citric acid, salicylic acid, and mandelic acid, and the amino acids include ethylenediaminetetraacetate (EDTA) and glutamic acid. , Aspartic acid and the like.

Of these, it is preferable to use oxycarboxylic acids or salts thereof, or polycarboxylic acids or salts thereof. Examples of these commercially available products include "Pozzolith No. 89" manufactured by NMB Corporation as an oxycarboxylic acid-based product, and "Quinflow 750" manufactured by Zeon Corporation as a polycarboxylic acid-based product.

The amount of the retarder to be added is 0.01 to 0.2 by weight based on the cement or the powder mixture containing the cement.
%. If the addition amount is less than 0.01%, it is 1 to 2 after kneading.
When the construction is performed after a lapse of time, the coarse aggregate covered with the paste or the mortar is likely to be peeled off on the surface layer of the permeable concrete pavement due to the load caused by traffic traffic. If the addition amount exceeds 0.2%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability decreases.

As the shrinkage reducing agent, chemical formula (1): RO
An alcohol compound represented by H or an alkylene oxide adduct of a lower alcohol represented by the chemical formula (2): RO (AO) _n H is preferred. Specifically, in the alcoholic compound represented by the chemical formula (1): ROH, R in the formula is an alkyl group having 4 to 6 carbon atoms or a cycloalkyl group having 5 to 6 carbon atoms,
Examples of such a group include an n-butyl group, an iso-butyl group, a tert-butyl group, an n-pentyl group, an iso-pentyl group, and a tert-pentyl group. Among the alcoholic compounds represented by the chemical formula (1): ROH, a preferred compound is a tert-butyl group, and as a commercial product, "AS21" manufactured by Nippon Cement Co., Ltd. is exemplified.

In the alkylene oxide adduct of a lower alcohol represented by the chemical formula (2): RO (AO) _n H, R in the formula is an alkyl group having 4 to 6 carbon atoms. Examples of such a group include an n-butyl group, an iso-butyl group, a tert-butyl group, an n-pentyl group, an iso-pentyl group, and a tert-pentyl group. A is one or two alkylene groups having 2 to 3 carbon atoms, such as an ethylene group and / or a propylene group. Note that n is an integer of 1 to 10. Among the alkylene oxide adducts of lower alcohols represented by the chemical formula (2): RO (AO) _n H, a preferable one is a propylene oxide (additional mole number 2) / ethylene oxide (additional mole number 3) block of n-butyl alcohol. As an adduct, commercially available products include "AS20" manufactured by Nippon Cement Co., Ltd.

The amount of the shrinkage reducing agent to be added is 0.5 to 5% by weight based on the cement or the powder mixture containing the cement.
0%. If the amount added is less than 0.5%, the
When the construction is performed after a lapse of about 2 hours, the coarse aggregate covered with the paste or the mortar is likely to be peeled off on the surface layer of the permeable concrete pavement due to the load caused by traffic of the traffic vehicle. If the addition amount exceeds 5.0%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability decreases.

Further, a retarder and a shrinkage reducing agent may be used in combination. In this case, the retarder is 0.01 to 0.2% by weight based on the cement or the powder mixture containing the cement,
The shrinkage reducing agent is preferably added in an amount of 0.1 to 3.0% by weight based on cement or a powder mixture containing cement.

When only a retarder is added, the amount of water is 16 to 28% by weight based on the cement or the powder mixture containing the cement. When the addition amount is less than 16%, the coating thickness of the paste or mortar becomes thin, so that the bending strength becomes small. If the added amount exceeds 28%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability decreases.

When a shrinkage reducing agent is added, the amount of water added is such that the total amount of the shrinkage reducing agent and water is 16 to 28% by weight with respect to cement or a powder mixture containing cement.
The amount is such that When the weight ratio is less than 16%, the coating strength of the paste or mortar becomes small, so that the bending strength becomes small. If the weight ratio exceeds 28%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability decreases.

The volume ratio of paste or mortar to coarse aggregate is 30 to 80%. If it is less than 30%, the coating thickness becomes thin, so that the bending strength becomes small. Also, 8
If it exceeds 0%, the granules after the granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down, so that the water permeability decreases.

The mixer used for kneading may be of any type used for kneading ordinary concrete, for example, an omni-type mixer, a pan-type mixer, a twin-screw mixer, or the like.

The method of kneading is not particularly limited, but generally, the granulation is carried out by charging the materials all at once into a mixer and kneading the mixture for one minute or more. Granulation can also be achieved by charging a material other than the coarse aggregate into a mixer, kneading the paste or mortar, and then charging the coarse aggregate and kneading for 1 minute or more.

It is preferable to carry the above-mentioned granulated material by using a dump truck. At the time of construction, the granules are compacted with a pressure vibrator and spread on the construction site. As the pressurizing vibrator, a tamping rammer, a plate compactor, a vibro compactor, a finisher, and the like conventionally used for concrete pavement can be used. After laying, cover the concrete pavement surface with a curing sheet and cure. The curing period is preferably at least two days. In the present invention, after the granulated product is compacted by a pressure vibrator and spread on a construction site, the initial compaction and the secondary compaction may be performed using a vibration roller. In this case, the bending strength can be improved.

[0030]

The present invention will be described below with reference to examples. The following materials were used as concrete materials in the following Examples and Comparative Examples. (1) Cement: Asano ordinary Portland cement manufactured by Nippon Cement Co., Ltd. (2) Blast furnace slag powder: Fine cement manufactured by Daiichi Cement Co., Ltd. (3) High performance water reducing agent: Mighty 150 (Naphthalene sulfone) manufactured by Kao Corporation Acid-based), (4) Fine aggregate: Hoshimeyama sand from Ichihara (particle size of 5 mm or less), (5) Coarse aggregate: crushed stone 6 from Ome (5-10 mm in diameter), crushed stone 7 from Ome (6-5) Delaying agent: a-1; Quinflow 750 (polycarbonate-based) manufactured by Zeon Corporation, a-2: Pozzolith No. manufactured by NMB Corporation. 89 (oxycarboxylic acid type); (7) Shrinkage reducing agent: b-1; AS21 manufactured by Nippon Cement Co., Ltd .; b-2; AS20 manufactured by Nippon Cement Co., Ltd.

[0031]Examples 1 to 12, Comparative Examples 1 to 5 Addition of retarder and shrinkage reducing agent to physical properties of concrete pavement
The effects were examined. (1) Mixing and kneading A retarder and a shrinkage reducing agent having the composition shown in Table 1 were added to other materials.
With a twin-screw mixer (0.1m^Three) At once, 4 minutes
The mixture was kneaded and mixed to obtain granules. In addition, concrete
85 parts by weight of cement and 15 layers of blast furnace slag powder
Parts, 1.5 parts by weight of high-performance water reducing agent, 100 parts of fine aggregate
Parts, 494 parts by weight of coarse aggregate (331 parts by weight of crushed stone No. 6, crushed stone
No. 7, 163 parts by weight), the total amount of water and shrinkage reducing agent is 22
It was made to be part by volume.

[0032]

[Table 1]

(2) Pavement Construction and Curing After the granules are allowed to stand for 2 hours, 100 × 60 × 1
Plate compactor (MVC-110)
H: Mikasa). Then, cover the concrete pavement surface with a curing sheet and cure for 2 days.
A pavement plate of × 60 × 15 cm was prepared.

(3) After the evaluation curing, the above-mentioned pavement slab was cut to produce two specimens of 15 × 5 × 40 cm. )), And the amount of peeling of the coarse aggregate coated with the paste or mortar was calculated in the same manner as the procedure for calculating the amount of abrasion. Also, cutting the paving slab, 1
Three specimens of 0 × 10 × 40 cm were prepared, and “JIS
A 1106 (Bending test method for concrete) ". Furthermore, the above-mentioned pavement plate was cut and three specimens of 10 × 10 × 20 cm were prepared, and “Interlocking Block Pavement Design and Execution Procedure 8-3”
The water permeability was measured according to the "water permeability test". Table 1 shows the results. Table 1 shows that when the amount of the retarder added is small (Comparative Example 2) and when the amount of the shrinkage reducing agent is small (Comparative Example 4), the amount of the coarse aggregate peeled is large.
On the other hand, when the addition amount of the retarder is large (Comparative Example 3) and when the addition amount of the shrinkage reducing agent is large (Comparative Example 5), it can be seen that the water permeability is small.

Examples 13 to 23, Comparative Examples 6 to 12 The physical properties of various concrete pavements were investigated when the addition amount of the retarder was fixed and the component composition of the concrete was changed. Each material was mixed in a twin-screw mixer (0.1
m ³ ) and kneaded and mixed for 4 minutes to obtain granules. After the obtained granules were allowed to stand for 2 hours, a pavement plate of 100 × 60 × 15 cm was produced in the same manner as in Example 1. This paved version was evaluated in the same manner as in Example 1. Table 3 shows the results. Tables 2 and 3 show that when the component composition of the concrete is out of the range of the present invention, either the bending strength or the water permeability is inferior.

[0036]

[Table 2]

[0037]

[Table 3]

Examples 24 to 34, Comparative Examples 13 to 19 The physical properties of various concrete pavements were examined when the addition amount of the shrinkage reducing agent was kept constant and the concrete component composition was changed. Each material was mixed in a twin-screw mixer (0.
1 m ³ ) and kneaded for 4 minutes to obtain granules. After the obtained granules were allowed to stand for 2 hours, a pavement plate of 100 × 60 × 15 cm was produced in the same manner as in Example 1. This paved version was evaluated in the same manner as in Example 1. Table 5 shows the results. Tables 4 and 5 show that when the component composition of the concrete is out of the range of the present invention, either the bending strength or the water permeability is inferior.

[0039]

[Table 4]

[0040]

[Table 5]

Examples 35 to 40 Tests were performed by changing the construction method. At a mixing ratio shown in Table 6, each material was put in a lump into a biaxial mixer (2.0 m ³ ) and kneaded and mixed for 4 minutes to obtain granules. After the obtained granules were allowed to stand for 2 hours, they were spread on a 350 × 300 × 15 cm formwork using a finisher made of ABG (TITAN411). In Examples 38 to 40, three reciprocations were performed without vibration and five reciprocations were performed with a vibration frequency of 3000 vpm using a vibration roller (SW70; manufactured by Sakai Heavy Industries, Ltd.).
Then, cover the concrete pavement surface with a curing sheet,
After curing for a day, a pavement plate of 350 × 300 × 15 cm was prepared. The obtained pavement plate was evaluated in the same manner as in Example 1.
Table 7 shows the results. Tables 6 and 7 show that when the vibration roller is used in addition to the finisher, the amount of peeling of the coarse aggregate is slightly reduced and the bending strength is slightly increased, but the water permeability is slightly reduced.

[0042]

[Table 6]

[0043]

[Table 7]

[0044]

The permeable concrete pavement according to the present invention is excellent in durability, strength and drainage. That is, the degree of separation of the coarse aggregate in the surface layer due to the load caused by traffic of the traffic vehicle is small, and it has a large bending strength of 5.5 N / mm ² or more and a large water permeability of 0.1 cm / sec or more.

Claims (6)

[Claims] An in-place permeable concrete pavement comprising a kneaded mixture of a pavement composition comprising coarse aggregate and a paste or mortar having a volume ratio of 30 to 80% with respect to 100% of the coarse aggregate. Wherein the paste or mortar is a powder mixture containing cement or cement, a fine aggregate having a weight ratio of 0 to 140% to the cement or cement-containing powder mixture, and a powder containing the cement or cement. A high performance water reducing agent having a weight ratio of 0.5 to 2.0% to the mixture; a retarder having a weight ratio of 0.01 to 0.2% to the cement or a powder mixture containing the cement; Pour-in-place permeable concrete pavement comprising 16 to 28% by weight of water with respect to a powder mixture containing: 2. The cast-in-place permeable concrete pavement according to claim 1, wherein the retarder is an organic acid or a salt thereof. 3. The cast-in-place water permeability according to claim 1, wherein the retarder is at least one selected from oxycarboxylic acids, polycarboxylic acids, and salts thereof. Concrete pavement. 4. An in-place permeable concrete pavement comprising a kneaded mixture of a pavement composition comprising coarse aggregate and a paste or mortar having a volume ratio of 30 to 80% with respect to 100% of the coarse aggregate. Wherein the paste or mortar is a powder mixture containing cement or cement, a fine aggregate having a weight ratio of 0 to 140% to the cement or cement-containing powder mixture, and a powder containing the cement or cement. A high-performance water reducing agent having a weight ratio of 0.5 to 2.0% to the mixture, a shrinkage reducing agent having a weight ratio of 0.5 to 5.0% to the cement or a powder mixture containing the cement, and a shrinkage reducing agent And water, the total amount of which is 16 to 28% by weight with respect to the cement or the powder mixture containing the cement. 5. An alcohol compound represented by ROH (R represents an alkyl group having 4 to 6 carbon atoms or a cycloalkyl group having 5 to 6 carbon atoms), or RO (AO). _n H (R is an alkyl group having 4 to 6 carbon atoms, A is one or two alkylene groups having 2 to 3 carbon atoms, and n is an integer of 1 to 10). The pour-in-place permeable concrete pavement according to claim 4, which is an alkylene oxide adduct. 6. A powder mixture comprising the cement as described above,
The cast-in-place permeable concrete pavement according to any one of claims 1 to 5, comprising at least 50% by weight of cement and at most 50% by weight of blast furnace slag.