JP2004316282A - Balustrade block - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a balustrade block provided with a sufficient deviation preventive effect, stability/durability, crashproofness, capable of reducing weight, and facilitating transportation/installation work. <P>SOLUTION: The balustrade block is formed of at least cement, pozzolana fine powder, fine aggregate finer not more than 2 mm grain size, water reducing agent, and a hardener of a compound including water, and has a cavity in the inside. The balustrade block includes inorganic particles with a specific area of 2,500-30,000 cm<SP>2</SP>/g in brain specific area and having a larger brain specific area than the cement. The inorganic particles are constituted of inorganic particles A with 5,000-30,000 cm<SP>2</SP>/g in brain specific area and inorganic particles B with 2,500-5,000cm<SP>2</SP>/g in brain specific area. The balustrade block includes one or more kinds of fibers selected from a metallic fiber, an organic fiber, and a carbon fiber in the compound. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a railing block for a wall railing provided on a bridge such as a general road or an expressway.
[0002]
[Prior art]
Wall bridges are installed on bridges such as general roads and expressways. The wall railing is provided to prevent a vehicle that has deviated from the travel lane from deviating outside the road, and needs to have a sufficient departure prevention effect. In an emergency such as a brake trouble, the vehicle is also used for an emergency stop such that the vehicle is rubbed against a railing on the wall, and it is necessary to provide sufficient stability and impact resistance. As a wall tall having such characteristics, a concrete wall tall has conventionally been used (for example, Patent Document 1).
[0003]
[Patent Document 1]
JP-A-9-296414
[Problems to be solved by the invention]
2. Description of the Related Art In recent years, with the increase in traffic, oxidized substances contained in exhaust gas of vehicles have deteriorated concrete wall railings, and replacement of concrete wall railings has been required. It is a common practice to replace wall railings by tearing off existing wall railings and manufacturing new railings by casting concrete in place. However, the method of casting in place has a problem that the replacement work is very complicated and the number of working days is long. On the other hand, it is conceivable that the existing wall railing is demolished and a new railing block is installed. However, the conventional concrete wall railing block has a weight of 0.8 to 1.0 ton / m, which is heavy. -There is a problem that the installation work is very time-consuming.
[0005]
The present invention has been made in view of the above-mentioned problems of the related art, and its object is to provide a sufficient departure prevention effect, stability / durability and impact resistance, and to reduce the weight. It is an object of the present invention to provide a railing block that can be easily transported and installed.
[0006]
[Means for Solving the Problems]
The inventor of the present invention has made intensive studies to solve the above-mentioned problems, and as a result, has solved the above-mentioned problems by providing a row block made of a cured product of a compound containing a specific material and having a hollow portion inside. The present invention was completed.
[0007]
That is, the present invention is at least a column block made of a cured product of a cement, a pozzolanic fine powder, a fine aggregate having a particle size of 2 mm or less, a water reducing agent, and a compound containing water, and has a hollow portion therein. It is a high block block (claim 1). Since the row block constructed in this way is made of a cured body that exhibits a compressive strength of 130 MPa or more and a bending strength of 20 MPa or more, it can have a sufficient departure prevention effect, stability / durability, and impact resistance. In addition, since the railroad block of the present invention is made of the above-described ultra-high-strength cured body, it can have a hollow portion inside, and can achieve weight reduction.
The row block may contain inorganic particles having a specific surface area of 2500 to 30000 cm ² / g and a specific surface area larger than that of the cement in the composition (claim 2). By including the inorganic particles in the composition as described above, the fluidity of the composition and the strength and durability of the row block can be improved.
The inorganic particles may be composed of inorganic particles A of Blaine specific surface area 5000~30000cm ² / g, the Blaine specific surface area 2500~5000cm ² / g and inorganic particles B (claim 3). By using two kinds of inorganic particles having different Blaine specific surface areas as described above, the fluidity of the blend can be further improved.
The row block may include one or more fibers selected from the group consisting of metal fibers, organic fibers, and carbon fibers in the composition (claim 4). By including metal fibers and the like in this manner, the bending strength, breaking energy, and the like of the row block can be improved.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail.
Examples of the cement used in the present invention include various Portland cements such as ordinary Portland cement, early-strength Portland cement, moderate heat Portland cement, and low heat Portland cement.
In the present invention, it is preferable to use early-strength Portland cement when it is intended to improve the early strength of the row block, and when it is intended to improve the fluidity of the composition, it is preferable to use a medium-heat Portland cement or the like. It is preferred to use low heat Portland cement.
[0009]
Blaine specific surface area of the cement, preferably ^{2500~5000cm 2 / g, 3000~4500cm 2 /} g is more preferable. If the value is less than 2500 cm ² / g, the hydration reaction becomes inactive, the strength development of the cured product is reduced, the strength of the row block is reduced, and it is difficult to reduce the weight of the row block. If it exceeds 5000 cm ² / g, it takes a long time to pulverize the cement, and the amount of water for obtaining a predetermined fluidity increases, so that the strength of the cured product decreases. Are reduced, and it becomes difficult to reduce the weight of the railing block.
[0010]
Examples of the pozzolanic fine powder include silica fume, silica dust, fly ash, slag, volcanic ash, silica sol, precipitated silica, and the like.
In general, silica fume and silica dust have a BET specific surface area of 5 to 25 m ² / g and do not require pulverization or the like, and thus are suitable as the pozzolanic fine powder of the present invention.
BET specific surface area of the pozzolanic substance fine powder is preferably ^{5~25m 2 / g, 8~25m 2 /} g is more preferable. When the value is less than 5 m ² / g, the strength of the cured product is reduced, so there are drawbacks such as a decrease in the strength of the high block and difficulty in reducing the weight of the high block, and more than 25 m ² / g. Then, since the amount of water for obtaining a predetermined fluidity increases, the strength of the cured product decreases, the strength of the high block decreases, and it becomes difficult to reduce the weight of the high block.
The compounding amount of the pozzolanic fine powder is 5 to 50 parts by mass, preferably 10 to 40 parts by mass with respect to 100 parts by mass of the cement. If the compounding amount is out of the range of 5 to 50 parts by mass, there is a drawback that the flowability is extremely reduced, so that it takes time and effort to produce a row block.
[0011]
In the present invention, fine aggregate having a particle size of 2 mm or less is used. Here, the particle size of the fine aggregate is an 85% mass cumulative particle size. If the particle size of the fine aggregate is more than 2 mm, the strength of the cured product is reduced, so that there are disadvantages such as a decrease in the strength of the column block and difficulty in reducing the weight of the column block, which is not preferable.
In the present invention, it is preferable to use a fine aggregate having a maximum particle size of 2 mm or less, and more preferably to use a fine aggregate having a maximum particle size of 1.5 mm or less, from the viewpoint of the strength development of the cured product. . In addition, from the viewpoint of the fluidity of the blend, it is preferable to use fine aggregate having a content of particles of 75 μm or less of 2.0% by mass or less, and a content of particles of 75 μm or less of 1.5% by mass or less. It is more preferable to use a certain fine aggregate.
As fine aggregate, river sand, land sand, sea sand, crushed sand, silica sand, and the like, or a mixture thereof can be used.
The blending amount of the fine aggregate is preferably from 50 to 250 parts by mass, and more preferably from 80 to 200 parts by mass, based on 100 parts by mass of the cement, from the viewpoint of the fluidity of the composition and the strength development of the cured product. Is more preferable.
[0012]
As the water reducing agent, a lignin-based, naphthalene-sulfonic acid-based, melamine-based, polycarboxylic acid-based water reducing agent, an AE water reducing agent, a high performance water reducing agent or a high performance AE water reducing agent can be used. Among these, it is preferable to use a high-performance water reducing agent or a high-performance AE water reducing agent having a large water-reducing effect, and it is particularly preferable to use a polycarboxylic acid-based high-performance water reducing agent or a high-performance AE water reducing agent.
The compounding amount of the water reducing agent is preferably from 0.1 to 4.0 parts by mass, more preferably from 0.1 to 2.0 parts by mass, based on 100 parts by mass of cement in terms of solid content. If the compounding amount is less than 0.1 part by mass, kneading becomes difficult, and the fluidity is reduced. If the compounding amount exceeds 4.0 parts by mass, material separation or remarkable setting delay occurs, and the strength of the cured product is reduced, so that the strength of the row block is reduced and it becomes difficult to reduce the weight of the row block. There are disadvantages.
The water reducing agent can be used in either liquid or powder form.
[0013]
The amount of water is preferably from 10 to 30 parts by mass, more preferably from 12 to 25 parts by mass, based on 100 parts by mass of cement. If the amount of water is less than 10 parts by mass, kneading becomes difficult, and the fluidity is reduced. When the amount of water exceeds 30 parts by mass, the strength of the cured product is reduced, and thus there are drawbacks such as a decrease in the strength of the row block and difficulty in reducing the weight of the row block.
[0014]
In the present invention, from the viewpoint of improving the fluidity of the composition and the strength development and durability of the cured product, the composition has a Blaine specific surface area of 2500 to 30000 cm ² / g and is larger than the cement. It is preferable to include inorganic particles having a Blaine specific surface area.
Examples of the inorganic particles include slag, limestone powder, feldspar, mullite, alumina powder, quartz powder, fly ash, volcanic ash, silica sol, carbide powder, nitride powder and the like. Among them, slag, limestone powder and quartz powder are preferably used in terms of cost and quality stability after curing.
Inorganic particles, Blaine specific surface area of preferably 2500~30000cm ² / g, more preferably at 4500~20000cm ² / g, and has a large Blaine specific surface area than the cement particles. When the Blaine specific surface area of the inorganic particles is less than 2500 cm ² / g, the difference in the Blaine specific surface area with the cement becomes small, and it becomes difficult to secure high fluidity (self-filling property). When it exceeds 30,000 cm ² / g, it takes time and effort to pulverize, so that it becomes difficult to obtain materials, and it becomes difficult to obtain high fluidity. There are drawbacks.
[0015]
Since the inorganic particles have a larger Blaine specific surface area than the cement, the inorganic particles have a particle size that fills the gap between the cement and the pozzolanic fine powder, ensuring high fluidity (self-filling property). Can be.
Difference Blaine specific surface area of the inorganic particles and the cement, from the viewpoint of the strength developing property after curing and flowability of the formulation is preferably not less than ^{1000cm 2 / g, 2000cm 2 /} g or more is more preferable.
The amount of the inorganic particles is preferably 55 parts by mass or less, more preferably 10 to 50 parts by mass, based on 100 parts by mass of the cement, from the viewpoint of the fluidity of the composition and the strength development of the cured product.
[0016]
In the present invention, two different types of inorganic particles A and inorganic particles B can be used in combination as the inorganic particles.
In this case, the inorganic particles A and the inorganic particles B may use the same type of powder (eg, limestone powder) or different types of powder (eg, limestone powder and quartz powder).
The inorganic particles A have a Blaine specific surface area of 5,000 to 30,000 cm ² / g, preferably 6,000 to 20,000 cm ² / g. The inorganic particles A have a larger Blaine specific surface area than the cement and the inorganic particles B.
When the Blaine specific surface area of the inorganic particles A is less than 5000 cm ² / g, the difference in the Blaine specific surface area between the cement and the inorganic particles B becomes small, and the fluidity and the like are lower than in the case where the above-mentioned one kind of inorganic particles is used. Not only is the effect of improving the particle size small, but also the use of two types of inorganic particles makes preparation of the material time-consuming, which is not preferable. When the Blaine specific surface area exceeds 30,000 cm ² / g, it takes time and effort to pulverize, so that it becomes difficult to obtain a material, and it becomes difficult to obtain high fluidity. .
[0017]
In addition, since the inorganic particles A have a larger Blaine specific surface area than the cement and the inorganic particles B, the inorganic particles A have a particle size that fills the gap between the cement and the inorganic particles B and the pozzolanic fine powder. And more excellent fluidity and the like can be secured.
The difference in the Blaine specific surface area between the inorganic particles A and the cement and the inorganic particles B (in other words, the difference in the Blaine specific surface area between the inorganic particles A and the cement and the inorganic particles B having the larger Blaine specific surface area) From the viewpoint of the fluidity of the product and the strength development of the cured product, it is preferably at least 1000 cm ² / g, more preferably at least 2000 cm ² / g.
[0018]
The Blaine specific surface area of the inorganic particles B is 2500 to 5000 cm ² / g. The difference between the Blaine specific surface area of the cement and the inorganic particles B is preferably at least 100 cm ² / g, from the viewpoint of strength development of the fluidity and curing of the formulation, 200 cm ² / g or more is more preferable.
If the Blaine specific surface area of the inorganic particles B is less than 2500 cm ² / g, the flowability is lowered and self-filling becomes difficult to obtain, so that there is a drawback that it takes time and effort to manufacture a row block and 5000 cm ² / g. When the value exceeds 2, since the numerical value of the Blaine specific surface area approaches the inorganic particles A, the effect of improving the fluidity and the like is reduced as compared with the case of using the above-mentioned one kind of inorganic particles. Since it is used, it takes time to prepare the material, which is not preferable.
Further, when the difference in the specific surface area between the cement and the inorganic particles B is 100 cm ² / g or more, the filling property of the particles constituting the composition is improved, and more excellent fluidity and the like can be secured. .
[0019]
The mixing amount of the inorganic particles A is preferably 50 parts by mass or less, more preferably 10 to 40 parts by mass with respect to 100 parts by mass of cement. The mixing amount of the inorganic particles B is preferably 40 parts by mass or less, more preferably 5 to 35 parts by mass with respect to 100 parts by mass of the cement. When the blending amount of the inorganic particles A and the inorganic particles B is out of the above-mentioned range, the effect of improving the fluidity and the like is reduced as compared with the case where the one kind of inorganic particles is used, and two kinds of inorganic particles are used. Is not preferable because it takes time to prepare the material.
In addition, the total amount of the inorganic particles A and the inorganic particles B is preferably 55 parts by mass or less, more preferably 10 to 50 parts by mass with respect to 100 parts by mass of the cement.
[0020]
In the present invention, from the viewpoint of greatly increasing the bending strength and the breaking strength of the cured product, it is preferable to blend one or more fibers selected from the group consisting of metal fibers, organic fibers, and carbon fibers into the blend. .
Metal fibers are blended from the viewpoint of greatly increasing the bending strength and the like of the cured body.
Examples of the metal fibers include steel fibers, stainless fibers, and amorphous fibers. Among them, steel fibers are excellent in strength, and are preferable in view of cost and availability. The size of the metal fiber is 0.01 to 1.0 mm in diameter and 2 to 30 mm in length from the viewpoint of preventing material separation of the metal fiber in the compound and improving the bending strength of the cured product. More preferably, the diameter is 0.05 to 0.5 mm and the length is 5 to 25 mm. The aspect ratio (fiber length / fiber diameter) of the metal fiber is preferably 20 to 200, and more preferably 40 to 150.
[0021]
The shape of the metal fiber is preferably a shape (for example, a spiral shape or a waveform) that gives some physical adhesive force, rather than a linear shape. With a spiral shape or the like, the bending strength is improved because the metal fiber and the matrix pull out and secure the stress.
Preferable examples of the metal fiber include, for example, an interface adhesion strength to a matrix of a cement-based hardened body made of a steel fiber having a diameter of 0.5 mm or less and a tensile strength of 1 to 3.5 GPa and having a compressive strength of 120 MPa. One having a maximum tensile force per unit area of the adhered surface of 3 MPa or more is exemplified. In this example, the metal fibers can be processed into a corrugated or spiral shape. Further, a groove or a protrusion for resisting movement (slip in the longitudinal direction) with respect to the matrix can be provided on the peripheral surface of the metal fiber of the present example. In addition, the metal fiber of the present example has a metal layer having a Young's modulus smaller than the Young's modulus of the steel fiber on the surface of the steel fiber (for example, one or more kinds selected from zinc, tin, copper, aluminum, and the like). May be provided.
[0022]
The amount of the metal fibers is preferably 4% or less, more preferably 0.5 to 3%, and particularly preferably 1 to 3% by volume in the composition. If the compounding amount exceeds 4%, the unit water amount increases in order to secure fluidity and the like, and even if the compounding amount is increased, the reinforcing effect of the metal fiber is not improved, so that it is not economical. This is not preferable because a so-called fiber ball easily occurs in the film.
[0023]
The organic fiber and the carbon fiber are blended from the viewpoint of increasing the breaking energy and the like of the cured product.
Examples of the organic fiber include vinylon fiber, polypropylene fiber, polyethylene fiber, and aramid fiber. Above all, vinylon fibers and / or polypropylene fibers are preferably used in view of cost and availability.
Examples of the carbon fiber include PAN-based carbon fiber and pitch-based carbon fiber.
The dimensions of the organic fiber and the carbon fiber are 0.005 to 1.0 mm in diameter and 2 to 30 mm in length from the viewpoint of preventing material separation of these fibers in the blend and improving the breaking energy after curing. It is more preferable that the diameter is 0.01 to 0.5 mm and the length is 5 to 25 mm. Further, the aspect ratio (fiber length / fiber diameter) of the organic fiber and the carbon fiber is preferably 20 to 200, and more preferably 30 to 150.
[0024]
The compounding amount of the organic fiber and the carbon fiber is preferably 10.0% or less, more preferably 1.0 to 9.0%, particularly preferably 2.0 to 8.0% by volume percentage in the composition. . If the blending amount exceeds 10.0%, the unit water amount increases to secure fluidity, etc., and even if the blending amount is increased, the fiber reinforcing effect is not improved, so that it is not economical, It is not preferable because a so-called fiber ball is easily generated therein.
[0025]
Next, physical properties (flow value, compressive strength, bending strength, breaking energy) of the compound and the cured product will be described.
The flow value of the formulation is preferably at least 230 mm, more preferably at least 240 mm. In addition, in this specification, the flow value is a value measured without performing a falling motion 15 times (this method) in a method described in “JIS R 5201 (Physical test method of cement) 11. Flow test”. In the specification, it is also referred to as “0-stroke flow value”).
In the flow test, the time required for the flow value to reach 200 mm is preferably within 10.5 seconds, more preferably within 10.0 seconds.
The compressive strength of the cured product is preferably at least 130 MPa, more preferably at least 135 MPa.
The bending strength of the cured body is preferably 20 MPa or more, more preferably 22 MPa or more, and particularly preferably 25 MPa or more. In particular, when the composition contains metal fibers, the flexural strength of the cured product is preferably 30 MPa or more, more preferably 32 MPa or more, and particularly preferably 35 MPa or more.
Fracture energy of the cured product, for example, metal fibers, when blended with any one or more organic fibers and carbon fibers, preferably least 10 KJ / m ² or more, more preferably 20 kJ / m ² or more.
[0026]
Next, an example of a row block according to the present invention will be described with reference to the drawings.
FIG. 1 is a longitudinal sectional view in the width direction of an example of a row block according to the present invention. The row block 1 is formed of an outer wall portion 2 and a hollow portion 3.
In the row block of the present invention, the thickness of the outer wall portion is preferably 2 to 10 cm from the viewpoint of the strength of the row block, durability and impact resistance, and further, from the viewpoint of weight reduction of the row block. More preferably, it is 4 to 8 cm.
In addition, the shape of the railing block of the present invention can be the same shape as the conventionally used cast-in-place concrete wall railing or railing block.
[0027]
A method for manufacturing a row block according to the present invention will be described.
The method of kneading the compound of the present invention is not particularly limited. For example, (1) water and a material other than a water reducing agent are previously mixed to prepare a premix material, and the premix material is prepared. A method in which water and a water reducing agent are put into a mixer and kneaded, (2) a powdery water reducing agent is prepared, materials other than water are mixed in advance to prepare a premix material, and the premix material and A method in which water is charged into the mixer and kneaded, (3) a method in which each material is individually charged into the mixer and kneaded, and the like can be adopted.
The mixer used for kneading may be any type used for kneading ordinary concrete, for example, an oscillating mixer, a pan-type mixer, a biaxial kneading mixer, or the like.
[0028]
After kneading, the compound is poured into a predetermined mold and molded, and then cured to produce the row block of the present invention.
Curing may be carried out by steam curing or aerial curing.
[0029]
The formulation used in the present invention has a value measured in the method described in “JIS R 5201 (Physical test method for cement) 11. Flow test” without performing 15 falling movements (in the present specification, The "0-strike flow value" is 230 mm or more, which is excellent in fluidity and has self-filling property, so that it is possible to easily manufacture (especially, mold) a row block.
Further, the cured product of the composition of the present invention exhibits a compressive strength of 130 MPa or more and a bending strength of 20 MPa or more. The row block made of the cured product can be provided with a hollow portion therein to reduce the weight. Can be achieved.
Further, the cured product of the composition of the present invention is extremely dense, and the row block made of the cured product is excellent in durability against exhaust gas and the like of vehicles.
[0030]
The railroad block according to the present invention can be installed on a bridge such as a general road or a highway using an anchor bolt or the like.
[0031]
【Example】
Hereinafter, the present invention will be described with reference to examples.
[1. Materials used]
The following materials were used.
(1) Cement; Low heat Portland cement (manufactured by Taiheiyo Cement Corporation; Blaine specific surface area 3200 cm ² / g)
(2) Pozzolanic fine powder; silica fume (BET specific surface area 10 m ² / g)
(3) Inorganic particles A; quartz powder A (Brain specific surface area 7500 cm ² / g)
(4) Inorganic particles B; quartz powder B (Brain specific surface area 4000 cm ² / g)
(5) Fine aggregate; silica sand (maximum particle diameter 0.6 mm, content of particles of 75 μm or less 0.3 mass%)
(6) Metal fiber; steel fiber (diameter: 0.2 mm, length: 13 mm)
(7) Water reducing agent; polycarboxylic acid-based high-performance AE water reducing agent (8) Water; tap water
Example 1
100 parts by mass of low-heat Portland cement, 32 parts by mass of silica fume, 39 parts by mass of quartz powder A, 120 parts by mass of silica sand, 1.0 part by mass of a high-performance AE water reducing agent (solid content relative to cement), and 22 parts by mass of water are put into a twin-screw mixer And kneaded.
The flow value of the composition was measured without performing a dropping motion 15 times in the method described in “JIS R 5201 (Physical test method for cement) 11. Flow test”. As a result, the flow value was 260 mm.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The compressive strength (average value of three strands) of the cured product was 210 MPa.
Further, the composition was poured into a 4 × 4 × 16 cm mold, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The bending strength (average value of three pieces) of the cured product was 25 MPa.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The water permeability of the cured product was measured by a variable water permeability test method according to “Geotechnical Society of Japan Standard JGS 0231 (Soil Permeability Test Method)”. As a result, no permeation of water was recognized, and the permeation depth was zero.
[0033]
Example 2
100 parts by mass of low heat Portland cement, 32 parts by mass of silica fume, 26 parts by mass of quartz powder A, 13 parts by mass of quartz powder B, 120 parts by mass of silica sand, 1.0 part by mass of high-performance AE water reducing agent (solid content relative to cement), 22 parts by mass of water Was charged into a twin-screw mixer and kneaded.
The flow value of the composition was measured without performing a dropping motion 15 times in the method described in “JIS R 5201 (Physical test method for cement) 11. Flow test”. As a result, the flow value was 285 mm.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The compressive strength (average value of three strands) of the cured product was 230 MPa.
Further, the composition was poured into a 4 × 4 × 16 cm mold, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The bending strength (average value of three pieces) of the cured product was 28 MPa.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The water permeability of the cured product was measured by a variable water permeability test method according to “Geotechnical Society of Japan Standard JGS 0231 (Soil Permeability Test Method)”. As a result, no permeation of water was recognized, and the permeation depth was zero.
[0034]
Example 3
100 parts by mass of low heat Portland cement, 32 parts by mass of silica fume, 26 parts by mass of quartz powder A, 13 parts by mass of quartz powder B, 120 parts by mass of silica sand, 1.0 part by mass of high-performance AE water reducing agent (solid content relative to cement), 22 parts by mass of water , Steel fibers (2% of the volume in the blend) were charged into a twin-screw mixer and kneaded.
The flow value of the composition was measured without performing a dropping motion 15 times in the method described in “JIS R 5201 (Physical test method for cement) 11. Flow test”. As a result, the flow value was 265 mm.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The compressive strength (average value of three strands) of the cured product was 230 MPa.
Further, the composition was poured into a 4 × 4 × 16 cm mold, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The bending strength (average value of three pieces) of the cured product was 47 MPa.
Further, the composition was poured into a mold of φ50 × 100 mm, placed at 20 ° C. for 48 hours, and then steam-cured at 90 ° C. for 48 hours. The water permeability of the cured product was measured by a variable water permeability test method according to “Geotechnical Society of Japan Standard JGS 0231 (Soil Permeability Test Method)”. As a result, no permeation of water was recognized, and the permeation depth was zero.
[0035]
【The invention's effect】
As described above, since the railroad block of the present invention is made of a cured body that exhibits a compression strength of 130 MPa or more and a bending strength of 20 MPa or more, it can have a sufficient departure prevention effect, stability, and impact resistance. . In addition, since the railroad block of the present invention is made of the above-described super-high-strength cured body, it can have a hollow portion inside and can be reduced in weight, so that transportation and installation work can be easily performed. Further, since the hardened body is extremely dense, the row block of the present invention made of the hardened body is excellent in durability against exhaust gas and the like of a vehicle.
[0036]
The composition used in the present invention has a flowability of 230 mm or more in the method described in “JIS R 5201 (Physical test method for cement) 11. Flow test” without performing 15 falling movements. And high self-filling properties, it is possible to easily manufacture (especially, mold) a high-rail block.
[Brief description of the drawings]
FIG. 1 is a longitudinal sectional view in the width direction showing an example of a row block according to the present invention.
[Explanation of symbols]
1 high rail block 2 outer wall 3 hollow

Claims (4)

At least a highway block comprising a hardened material of a composition containing cement, fine pozzolanic powder, fine aggregate having a particle size of 2 mm or less, a water reducing agent, and water, and having a hollow portion therein. block. The formulation, by Blaine specific surface area of 2500~30000cm ² / g, and railing block of claim 1 further comprising inorganic particles having a large Blaine specific surface area than the cement. Inorganic particles, and inorganic particles A of Blaine specific surface area 5000~30000cm ² / g, railing block according to claim 2, wherein comprising an inorganic particles B of Blaine specific surface area 2500~5000cm ² / g. The row block according to any one of claims 1 to 3, wherein the blend contains one or more fibers selected from the group consisting of metal fibers, organic fibers, and carbon fibers.

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