JP2001206761A - High-early-strength type water-permeable site concrete and pavement of roadway - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide water-permeable site concrete expressing 4.5 N/mm2 or higher flexural strength at one day of age according to the material test regulation and having 0.1 cm/second or larger coefficient of water-permeability. SOLUTION: This water-permeable concrete is obtained from the kneaded material which has the composition consisting of coarse aggregate and paste or mortar of 30-80% volume ratio based on the volume of the coarse aggregate and is used for paving a roadway at site. The paste or mortar contains 100 parts weight cement or powdery mixture containing cement, 0-140 parts weight fine aggregate, 3-15 parts weight clinker-pulverized material, 0.1-5.0 parts weight gypsum, 0.4-2.2 parts weight water reducing agent and 16-29 parts weight water. The clinker-pulverized material consists of one or more compositions selected from among 3CaO.SiO2-2CaO.SiO2-CaO-gap filling material system clinker composition, 3CaO.SiO2-CaO-gap filling material system clinker composition, 2CaO.SiO2-CaO-gap filling material system clinker composition and CaO- gap filling material system clinker composition and contains 50-92 wt.% CaO crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an early-strength cast-in-place permeable concrete used for sidewalks, roadways, and the like.
The present invention relates to a high-strength cast-in-place permeable concrete that can exhibit a bending strength of 4.5 N / mm ² or more in one day of material and enables early traffic opening even when used on a roadway.

[0002]

2. Description of the Related Art Permeable concrete has characteristics such as good drainage of rainwater, sound absorption, and planting of vegetation. Therefore, permeable concrete is suitable for road pavement, side walls of roads, revetment of rivers, and the like. It is used for various applications. However, since the permeable concrete has voids inside, it has a lower bending strength than ordinary concrete, and it has been difficult to apply the permeable concrete to a road with a large traffic volume.

[0003] In recent years, as a result of research into overcoming the problem of strength, permeable concrete having both excellent water permeability and large bending strength has been developed, and has been used for paving roads with heavy traffic. Are also being considered. For example,
JP-A-10-252006 discloses that a water-permeable concrete pavement having a large bending strength and a good water-permeability coefficient can be obtained by specifying the amount of a paste or mortar used together with coarse aggregate, the constituent components, and the like. Is disclosed.

[0004]

In the cast-in-place permeable concrete pavement described in the above-mentioned publication, after laying the kneaded material of the pavement composition, the pavement is cured for two days or more in order to develop a predetermined bending strength. There is a need. Therefore, when the in-situ permeable concrete pavement is applied to roads, etc., 2
During the curing period of more than one day, traffic had to be cut off. Therefore, it is possible to shorten the curing period, and as a result, there has been a demand for a high-strength cast-in-place permeable concrete that can be quickly opened to traffic even when applied to a roadway or the like.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to solve the above-mentioned problems, and as a result, by specifying the components of concrete and their mixing ratios, it has been possible to obtain a certain level of good water permeability. It has been found that a permeable concrete having the above properties and exhibiting a certain strength or more in a short curing period can be obtained, and the present invention has been completed.

That is, the early-strength cast-in-place permeable concrete according to claim 1 is a kneaded product of a composition comprising a coarse aggregate and a paste or mortar having a volume ratio of 30 to 80% to the coarse aggregate. The permeable concrete is laid, the paste or mortar, cement or cement-containing powder mixture 100 parts by weight, fine aggregate 0-140 parts by weight,
Clinker ground material 3-15 parts by weight, gypsum 0.1-5.0 parts by weight, water reducing agent 0.4 to 2.2 parts by weight, contains water 16 to 29 parts by weight, the clinker pulverized _{material, 3CaO · SiO 2 -2CaO · SiO} 2 -CaO - interstitial material based clinker composition, 3CaO · SiO ₂ -CaO- gap material based clinker composition, 2CaO · SiO ₂ -CaO- gap material based clinker composition 1 selected from among CaO- gap material based clinker composition More than seeds, and 50-92% by weight of CaO crystals
It is characterized by containing. With this configuration, one day after the start of curing, a bending strength of 4.5 N / mm ² or more is developed, and a water permeability of 0.1 cm / sec or more can be secured. Here, the cement or the powder mixture containing the cement is, for example, 50 to 100% by weight of Portland cement, 50 to 0% by weight of blast furnace slag powder and / or
Or fly ash (claim 2). The early-strength cast-in-place permeable concrete is suitably used, for example, as a road pavement (claim 3).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The materials constituting the early-strength cast-in-place permeable concrete of the present invention and the mixing ratio thereof are as follows. (1) Coarse Aggregate The coarse aggregate includes gravel, crushed stone, a mixture thereof, and lightweight aggregate having a particle size of 2.5 to 20 mm.

(2) Cement or Powder Mixture Containing Cement As the cement, for example, Portland cement such as ordinary, fast-strength, moderate heat, low heat Portland cement, white cement, alumina cement and the like are used. The powder mixture containing cement refers to a mixture obtained by adding one or more inorganic powders selected from blast furnace slag powder, fly ash, limestone powder, silica stone powder, silica fume and the like to the cement. Among inorganic powders, blast furnace slag powder or fly ash is preferred. The proportion of cement in the powder mixture containing cement is preferably set to 50% by weight or more in order to ensure strength development.

(3) Fine aggregate The fine aggregate includes river sand, sea sand, mountain sand, crushed sand, or a mixture thereof. As fine aggregate, when the particle size of the coarse aggregate is 5 mm or more, the particle size is less than 5 mm, preferably 2.5 m
m or less, more preferably 1.0 mm or less granules are used, and when the particle size of the coarse aggregate is 2.5 mm or more and less than 5 mm, the particle size is 2.5 mm
Particles having a diameter of less than 1.5 mm, preferably 1.5 mm or less, more preferably 0.5 mm or less are 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 amount of the fine aggregate to be added is 0 to 140 parts by weight, preferably 40 to 130 parts by weight, based on 100 parts by weight of the cement or the powder mixture containing the cement. By adding fine aggregate, shrinkage due to drying after curing can be suppressed. When the amount of fine aggregate exceeds 140 parts by weight,
It is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of timber age, and it is difficult to open the traffic early when it is used on a roadway.

[0011] (4) clinker pulverized clinker _{grind, 3CaO · SiO 2 -2CaO · SiO} 2 -CaO- gap material based clinker composition, 3CaO · SiO ₂ -CaO- gap material based clinker composition, 2CaO · SiO _It contains at least one selected from the group consisting of a _2- CaO-intercalated substance clinker composition and a CaO-intercalated substance clinker composition, and contains 50 to 92% by weight of CaO crystals. In other words, clinker ground product comprises at least CaO crystal and the gap material as a major minerals, alite as an optional component (3CaO · SiO ₂₎ and / or grinding the clinker composition comprising a belite (2CaO · SiO ₂₎ And containing 50 to 92% by weight of CaO crystals.

In this specification, "3CaO.SiO"_Two
−2CaO ・ SiO_Two-CaO-interstitial material-based clinker composition "
Is 0.5% by weight or more of alite (3CaO.SiO_Two) And 0.5
Belite (2CaO ・ SiO)_Two) And CaO crystal
And interstitial material. "3C
aO ・ SiO_Two-CaO-interstitial material clinker composition ''
Weight of alite (3CaO ・ SiO_Two) And CaO crystal
And interstitial material, belite (2CaO.SiO_Two)of
It is defined as having a content of less than 0.5% by weight. "2Ca
O ・ SiO_Two-CaO-interstitial material clinker composition ''
Belite (2CaO ・ SiO)_Two) And CaO crystal
And interstitial material, alite (3CaO.SiO _Two)of
It is defined as having a content of less than 0.5% by weight. "CaO
-Interstitial clinker composition "means CaO crystals and interstitial
Quality and contains alite (3CaO ・ SiO_Two) And Be Light
(2CaO ・ SiO_Two) Are less than 0.5% by weight
Is defined as

When the content of CaO crystals contained in the clinker pulverized product is less than 50% by weight, it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age, so that an early use when used on a roadway is difficult. Opening traffic becomes difficult. When the content exceeds 92% by weight, the paste or mortar becomes difficult to be coated on the coarse aggregate, and it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age. It becomes difficult to open traffic.

The interstitial material is similar to a mineral that fills a space between alite and belite in the pulverized cement clinker, and specifically, a calcium ferrite mineral such as 2CaO.Fe ₂ O ₃ , 3CaO.Al ₂ calcium aluminate mineral O ₃ or the like, _{or, 6CaO · Al 2 O 3 ·} Fe 2 O 3, 4CaO · Al 2 O 3 · F
e ₂ O _3, calcium alumino ferrite minerals such as _{6CaO · 2Al 2 O 3 · Fe} 2 O 3. The content of the interstitial substance contained in the clinker pulverized product is usually 0.5% by weight or more.

The amount of the pulverized clinker to be added is 3 to 15 parts by weight, preferably 4 to 12 parts by weight, based on 100 parts by weight of cement or a powder mixture containing cement. 3 added
If it is less than the weight part, it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age, and it is difficult to open the traffic early when it is used on a roadway. If the amount exceeds 15 parts by weight, the water permeability will decrease and the cost will increase. It is preferable to use a clinker pulverized material having a Blaine specific surface area of 3,000 cm ² / g or more.
It is particularly preferred to use those of ~ 6,000 cm ² / g.

The method for producing the clinker pulverized product is as follows. First, calcareous raw materials, clay raw materials, quartzite, slags,
After mixing the gypsum and the like to obtain a raw material mixture, using a rotary kiln or the like, under a temperature condition of 1,300 to 1,600 ° C., sufficiently bake the raw material mixture until a target clinker mineral composition is obtained. Baking to obtain a clinker composition. Thereafter, the obtained clinker composition may be pulverized so as to have a desired Blaine specific surface area.

(5) Gypsum Gypsum includes anhydrous gypsum, hemihydrate gypsum, dihydrate gypsum, or a mixture thereof. Above all, it is preferable to use anhydrous gypsum from the viewpoint of strength development. The amount of gypsum added is 0.1 to 5.0 parts by weight, preferably 0.1 to 2.0 parts by weight, based on 100 parts by weight of cement or a powder mixture containing cement.
Parts by weight. If the addition amount is less than 0.1 part by weight, it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age, and it is difficult to quickly open the traffic when used in a roadway, and the workability is also deteriorated. If the amount exceeds 5.0 parts by weight, the water permeability will decrease and the cost will increase. It is preferable to use gypsum having a specific surface area of 2,500 cm ² / g or more, and 3,000 to 10,000 c
It is particularly preferred to use those of m ² / g.

(6) Water reducing agent Examples of the water reducing agent include alkyl allyl sulfonic acid, naphthalene sulfonic acid, melamine sulfonic acid,
Various water reducing agents such as oxycarboxylic acid type and polycarboxylic acid type (water reducing agent, AE water reducing agent, high performance water reducing agent, high performance AE water reducing agent) are exemplified. Among them, high performance water reducing agent and high performance A
The E water reducing agent is preferable because it has a large water reducing effect. One type of water reducing agent may be used alone, or two or more types may be used in combination, and either a liquid or a powdery type can be used.

The amount of the water reducing agent is 0.4 to 2.2 parts by weight based on 100 parts by weight of cement or a powder mixture containing cement. If the addition amount is less than 0.4 parts by weight, 4.5N / day
It is difficult to obtain a bending strength of not less than mm ^2, and it is difficult to open the traffic early when used on a roadway. If the addition amount exceeds 2.2 parts by weight, 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.

(7) Water The amount of water depends on the amount of cement or powder mixture containing cement.
It is 16 to 29 parts by weight with respect to parts by weight. If the amount of water is less than 16 parts by weight, it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age, and it is difficult to open the traffic early when used on a roadway. If the amount of water exceeds 29 parts by weight, 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.

The volume ratio of the paste or mortar to the coarse aggregate is 30 to 80% (outside ratio) with respect to 100% of the coarse aggregate. If the volume ratio is less than 30%, it is difficult to obtain a bending strength of 4.5 N / mm ² or more in one day of the material age, and it is difficult to open the traffic early when used on a roadway. If the volume ratio exceeds 80%, the granules after granulation are bonded to each other, do not become independent granules, and the paste or mortar flows down.
Permeability decreases.

The mixer used for kneading is not particularly limited, and may be kneaded with a conventional mixer such as a pan-type mixer or a twin-screw mixer. As a kneading method, a method in which materials are collectively put into a mixer and kneaded for 1 minute or more, or a material other than a water reducing agent and water is put in a mixer and kneaded,
A method in which a water reducing agent and water are charged and kneaded for 1 minute or more is exemplified. The transport of the kneaded material from the concrete factory to the construction site may be performed using any of a dump truck and an agitator truck.

At the time of construction, the above kneaded material is compacted by a pressure vibrator and spread on a 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, the concrete pavement surface is covered with a curing sheet and cured for one day. The early-strength cast-in-place permeable concrete of the present invention can exhibit a bending strength of 4.5 N / mm ² or more in one day of material age. The thickness of concrete pavement is usually about 25 to 30 cm in the case of a road with heavy traffic. Concrete pavement can be applied to sidewalks, parking lots, river banks, and the like, in addition to roadways.

In the present invention, a thermoplastic resin such as an ethylene / vinyl acetate copolymer or an acrylic copolymer may be added to the paste or mortar as long as the purpose is not impaired. Blending strength can be improved by blending these thermoplastic resins. Further, a pigment such as red iron oxide may be added as long as the purpose is not impaired.

[0025]

The present invention will be described below with reference to examples. [Examples 1 to 15, Comparative Examples 1 to 11] Materials used (1) Clinker pulverized limestone, clay, silica, iron raw material, anhydrous gypsum, CaO: 94.7
Wt%, SiO _2; 2.3 wt%, Al ₂ O _3; 0.7 wt%, Fe ₂ O _3;
0.2% by weight, MgO; 0.9% by weight, SO ₃ ; 0.1% by weight, CaO crystal; 89.7% by weight, alite; 0.2% by weight, belite; 6.6% by weight, interstitial substance: 2.2% by weight A raw material mixture was prepared so as to have a composition. The raw material mixture was baked in a rotary kiln at a firing temperature of 1,300 to 1,600 ° C. and a residence time of 60 to 120 minutes to produce a clinker, and the obtained clinker was pulverized to a Blaine specific surface area of 4,500 cm ² / g.

(2) Materials other than pulverized clinker The following materials were used. Cement; ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.) Blast furnace slag; fine cement 10A (manufactured by Daiichi Cement Co., Ltd.) High-performance water reducing agent: "Mighty 100" (trade name) (manufactured by Kao Corporation) aggregate; Ichihara producing fine pit sand (particle diameter 2.5mm or less) coarse aggregate; Ome producing crushed stone No.6 (particle size 5～13Mm) gypsum; anhydrite (first cement Co., Blaine specific surface area 4,000 cm ² / g) Water; tap water

2. Mixing and Kneading of Porous Concrete Using the above-mentioned materials, the mixture was put into a biaxial forced kneading mixer (0.1 m ³ ) at a time according to the mixing shown in Table 1, and kneaded for 4 minutes.
Independent granules in a state where the coarse aggregate was covered with a paste or mortar made of a material other than the coarse aggregate were prepared.

[0028]

[Table 1]

3. Molding Each of the above granules is put into a 50 × 40 × 10 cm formwork, and the porosity is
It was laid with a plate compactor (MVC-110H; manufactured by Mikasa Corporation) so as to have a concentration of 15%. After laying, cover the concrete pavement surface with a curing sheet and cure for one day, then 100x60x15c
m permeable pavement slab was prepared.

The pavement slab was cut to prepare three specimens of 10 × 10 × 40 cm, and the flexural strength was measured according to “JIS A 1106 (Method of testing flexural strength of concrete)”. Also, cut the above paving slab, and set a 10 × 10 × 20 cm specimen
This was prepared and the permeability was measured in accordance with "Interlocking Block Pavement Design and Construction Procedure 8-3 Permeability Test".
Table 2 shows the results.

[0031]

[Table 2]

[0032]

The early-strength cast-in-place permeable concrete of the present invention can exhibit a large bending strength (4.5 N / mm ² or more) in one day of material and a large coefficient of water permeability (0.1 cm / day). se
c or more). Therefore, the curing period can be shortened from two or more days in the past to about one day, and when applied to a roadway or the like, traffic can be opened early.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) C04B 22/14 C04B 22/14 B 28/08 28/08 E01C 7/14 E01C 7/14 // C04B 103 : 30 C04B 103: 30 111: 00 111: 00 (72) Inventor Katsutoshi Ichikawa 2-4-2 Daisaku, Sakura-shi, Chiba Pref. Inside the Sakura Research Institute, Pacific Cement Co., Ltd. (72) Inventor Kazuyoshi Shirai 2 Daisaku, Sakura-shi, Chiba -4-2 Taiheiyo Cement Co., Ltd. Sakura Research Institute (72) Inventor Yoshihide Shimoyama 2-4-2 Daisaku, Sakura City, Chiba Pref. PA27 PA29 PB03 PB04 PB11 PC01 PC03

Claims (3)

[Claims] 1. The method of claim 1, wherein the volume ratio of the coarse aggregate to the coarse aggregate is 30.
~ 80% paste or mortar and a kneaded mixture of a composition comprising a kneaded material, wherein the paste or mortar is cement or cement, 100 parts by weight of a powder mixture containing cement, 0-140 parts by weight of fine aggregate, 3-15 parts by weight of pulverized clinker, 0.1-5.0 parts by weight of gypsum, water reducing agent
0.4 to 2.2 parts by weight, contains water 16 to 29 parts by weight, the clinker pulverized _{material, 3CaO · SiO 2 -2CaO · SiO} 2 -CaO
- interstitial material based clinker composition, 3CaO · SiO ₂ -CaO- gap material based clinker composition, 2CaO · SiO ₂ -CaO- gap material based clinker composition 1 selected from among CaO- gap material based clinker composition More than seeds, and CaO crystal 50 ~ 9
Early-strength cast-in-place permeable concrete characterized by containing 2% by weight. 2. The cement or a powder mixture containing the cement comprises 50-100% by weight of Portland cement,
2. The early-strength cast-in-place permeable concrete according to claim 1, comprising blast furnace slag powder and / or fly ash in an amount of about 0% by weight. 3. A pavement for roadways comprising the early-strength cast-in-place permeable concrete according to claim 1.