JP4937701B2 - Grout composition, grout mortar and grout method - Google Patents

Description

  The present invention mainly relates to a grout composition, grout mortar, and grout method that are suitable for use in filling concrete repair sites and have low cure shrinkage and durability.

Conventionally, for concrete repair (cross-sectional repair), for example, a material containing a fast-hardening cement, a short fiber having a fiber length of 3 to 20 mm, and a re-emulsified powder resin is used (see Patent Document 1). In addition, a material in which cement is mixed with classified fly ash having a fineness of 5000 cm ² / g or more, short fibers having a fiber length of 3 to 20 mm, and re-emulsifying powder resin is disclosed (see Patent Document 2). Further, it contains a cement, at least one polymer of a polyacrylic ester resin system, a styrene butadiene synthetic rubber system, or a vinyl acetate berba acrylic copolymer system, and an organic shrinkage reducing agent having a surface-active action. A polymer cement composition is proposed (see Patent Document 3). Furthermore, materials containing fibers have been developed for the purpose of preventing initial cracking (see Non-Patent Document 1). Moreover, the manufacturing method of the melt-spun basalt fiber is disclosed (refer patent document 4).
JP 11-278903 A JP 2001-322858 A JP 2003-55018 A Toshisuke Hamada, Hisashi Suemori, Tadashi Saito, Takayuki Hirai: Experimental study on suppression of plastic shrinkage cracking of concrete with vinylon short fibers, Annual report on concrete engineering, vol. 22, no. 2, pp. 319-324, 2000 Japanese translation of National Publication No. 09-500080

However, the above materials are not clear for long-term durability, and also have good fluidity (grouting properties), no shrinkage, and bleeding characteristics, etc., required as a grout material for repairing concrete. It was not clear.
The present invention provides a grout composition, a grout mortar, and a grout method that solve the above problems.

That is, the present invention provides (1) Portland cement, an expanded material, a re-emulsifying powder resin, a melt-spun basalt fiber in a converged state in which single fibers having a fiber length of 2 to 15 mm and a fiber diameter of 2 to 50 μm are bundled A shrinkage reducing agent, a water reducing agent, an antifoaming agent, and an aggregate , the expansion material is 1 to 20 parts with respect to 100 parts of Portland cement, and the re-emulsifying powder resin is 100 parts in total of cement and expansion material. 3 to 20 parts, 0.1 to 10 parts of melt-spun basalt fiber to 100 parts of the total of Portland cement and expansion material, and 0.1% of shrinkage reducing agent to 100 parts of cement and expansion material. 3 to 7 parts, 0.05 to 3 parts in terms of solid matter with respect to a total of 100 parts of cement and expansion material, and 0.3 to 0 parts of defoaming agent with respect to a total of 100 parts of cement and expansion material .Part 1, aggregate is Portland cement Is 150 to 300 parts per 100 parts of the expandable member, grout composition, (2) (1) grout composition and water Ri greens were mixed, and the cement in an amount of water grout composition It is a grout mortar which is 30 to 50 parts with respect to a total of 100 parts of the expanding material, and a grout method using a grout mortar of ( 3 ) ( 2 ).

  The grout mortar using the grout composition of the present invention has the effects of high fluidity, low cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

Hereinafter, the present invention will be described in detail.
In the present invention, “parts” and “%” are based on mass unless otherwise specified.

  The Portland cement used in the present invention is not particularly limited, and is commonly used, such as normal, early strong, moderately hot, and very early strong Portland cement, such as Portland cement, fly ash and blast furnace Various mixed cements mixed with slag and the like, and those obtained by pulverizing these various mixed cements can also be used.

  The expansion material used in the present invention is not particularly limited, and generally used calcium sulfoaluminate expansion material, calcium aluminoferrite expansion material, quick lime expansion material, and the like can be used.

  The amount of the expansion material used is preferably 1 to 20 parts, more preferably 2 to 15 parts, with respect to 100 parts of Portland cement (hereinafter referred to as cement). If it is less than 1 part, shrinkage may not be sufficiently suppressed, and if it exceeds 20 parts, the amount of expansion may be excessive.

  Examples of the re-emulsification type powder resin (hereinafter referred to as powder resin) used in the present invention include polyacrylic acid ester, vinyl acetate, ethylene-vinyl acetate, vinyl acetate-vinyl versatate, styrene-acrylic acid ester, or acrylic ester- It is possible to use a powdery resin mainly composed of vinyl acetate-vinyl versatate, etc. Among them, those having acrylic acid ester-vinyl acetate-vinyl versatate as the main component from the viewpoint of durability. More preferred. The re-emulsified powder resin can be produced by any method, including a pulverization method and an anti-blocking method.

The polymer dispersion obtained by diluting a polymer with a solvent is usually a method in which a cement mortar premix product and water are weighed and mixed and used. However, the powder resin of the present invention has a moisture content higher than that of the polymer dispersion. Because it is extremely low in content, it is difficult to harden even if it is mixed with cement without adding water, so pre-mixing eliminates the cumbersome work of measuring and mixing polymers at the construction site. This improves construction workability.
Further, since the powder resin is premixed with the cement, the powder resin acts evenly dispersed, and therefore acts more advantageously in terms of adhesion strength to the concrete than in the case where it is added later.

  As for the usage-amount of powder resin, 3-20 parts is preferable with respect to a total of 100 parts of a cement and an expandable material. If it is less than 3 parts, durability and adhesion performance may be insufficient. If it exceeds 20 parts, the cost may increase and fluidity during freshness may not be ensured.

The melt-spun basalt fiber used in the present invention (hereinafter referred to as basalt fiber) is an amorphous artificial mineral fiber that is made from natural basalt and melt-spun at a high temperature. Its features are excellent heat resistance compared to organic fibers, superior chemical resistance compared to glass fibers and rock wool, and a density of approximately 2.8 g / cm ^3, which is similar to dry mortar and is uniformly mixed It is characterized by excellent properties.
The fiber diameter of the basalt fiber is preferably 2 to 50 μm, and more preferably 7 to 20 μm. If it is smaller than 2 μm, it is difficult to produce stably, and if it exceeds 50 μm, the effect of reducing initial cracks may be reduced.
2-15 mm is preferable and, as for the fiber length of a basalt fiber, 5-10 mm is more preferable. If it is less than 2 mm, the effect of reducing initial cracks is small, and if it exceeds 15 mm, the dispersibility when mixed in dry mortar may deteriorate.
The basalt fiber is not in a single fiber state in which the fibers are loosened independently (the fiber diameter is 0.1 mm or more), but in a converged state in which single fibers with a fiber diameter of 50 μm or less are bundled with a sizing agent or the like. It is preferable to use it. By making it into a convergent state with moderate adhesive strength, it can be easily loosened and mixed evenly when mixed with dry mortar.

  The amount of basalt fiber used is preferably from 0.1 to 10 parts, more preferably from 0.3 to 5 parts, based on a total of 100 parts of cement and expansion material. If it is less than 0.1 part, the cracking prevention effect may not be sufficient, and if it exceeds 10 parts, kneadability and workability may be deteriorated.

  The shrinkage-reducing agent used in the present invention is one that prevents the unreacted moisture of the kneaded water from escaping and suppresses the drying shrinkage of the cement hydrate. Specifically, the alcohol-based, lower alcohol alkylene oxide derivative is used. Organic compounds having surface activity such as system, glycol, glycol ether / amino alcohol derivative, and polyether can be used.

  The amount of the shrinkage reducing agent used is preferably 0.3 to 7 parts with respect to 100 parts in total of the cement and the expansion material. If it is less than 0.3 part, the shrinkage reducing agent effect may not be sufficient, and if it exceeds 7 part, the cost increases, and the fluidity at the time of freshness may decrease.

In the present invention, a water reducing agent is used in the grout composition in order to ensure fluidity as a grout mortar and reduce the unit water amount. The water reducing agent can be used in either powder or liquid form.
The water reducing agent is not particularly limited, and examples thereof include polyol derivatives, lignin sulfonates and derivatives thereof, and high-performance water reducing agents, and one or more of these can be used. Among these, a high performance water reducing agent is preferable from the viewpoint of fluidity and water reducing effect.

  Examples of the high-performance water reducing agent include a naphthalene sulfonate, a melamine sulfonate, a formalin condensate of an alkyl allyl sulfonate, and a polycarboxylic acid polymer compound. Among these, it is more preferable to selectively use one or more of naphthalene sulfonate, melamine sulfonate, and polycarboxylic acid polymer compound, which have high setting retarding effect, fluidity, and pumpability.

  The amount of water-reducing agent used is preferably 0.05 to 3 parts, more preferably 0.1 to 2 parts, in terms of solid matter, with respect to 100 parts in total of cement and expansion material. If the amount is less than 0.05 part, good fluidity may not be obtained. If the amount exceeds 3 parts, setting delay may be caused more than necessary, and the strength development may be adversely affected.

  The antifoaming agent used in the present invention is not particularly limited, and it reduces entrained air when mixing the powder resin and contributes to improving the compression / bending strength of the hardened cement body. Nonionic surfactants such as polyoxyalkylene fatty acid esters can be used.

  The use amount of the antifoaming agent is preferably 0.01 to 0.05 part with respect to 100 parts in total of the cement and the expansion material. If it is less than 0.01 part, the defoaming effect may be insufficient, and if it exceeds 0.05 part, the effect may not be enhanced and the strength may be lowered.

The aggregate used in the present invention is not particularly limited, and is used for improving the fluidity of the cement kneaded product and improving the durability of the cement hardened body, such as river sand, sea sand, and quartz sand. It can be used.
Furthermore, in order to obtain a hardened cement body having desired characteristics, there is a range suitable for the particle size constitution and blending amount, and the particle size of the aggregate is preferably 4 mm or less, and further less than 1.2 mm Is preferably 50 to 75%, and 1.2 to 4 mm is preferably 50 to 25%, and more preferably a mixture of 1.2 to 4 mm is 45 to 25%. When the maximum particle size exceeds 4 mm, the fluidity and filling properties are affected. When the ratio of 1.2 to 4 mm is less than 25%, the durability is affected. When it exceeds 50%, sufficient early strength may not be obtained. is there.

  The amount of aggregate used is preferably 150 to 300 parts, more preferably 150 to 250 parts, with respect to 100 parts in total of cement and intumescent material. If it is less than 150 parts, cracks may easily occur, and if it exceeds 300 parts, it may be difficult to ensure sufficient fluidity.

  In the present invention, it can also be used in combination with fiber materials other than basalt fibers such as various organic fibers, carbon fibers, and steel fibers within a range that does not affect the performance. Furthermore, if necessary, other admixtures or admixtures within the range that does not impair the purpose of the grout mortar of the present invention, that is, pozzolanic substances such as fly ash and silica fume, rust preventives, non-separable admixtures in water such as methylcellulose , Thickeners, water retention agents, waterproofing agents, foaming agents, antifreeze agents, and coloring agents can be used in combination.

  The grout mortar of the present invention is preferably used in a premix type that can be used by mixing all of the components constituting the grout composition in advance, adding water and kneading on site, but some of the components Alternatively, it is also possible to prepare the whole by mixing at the site of use.

  The amount of water used in the present invention is preferably from 30 to 50 parts, more preferably from 35 to 45 parts, based on 100 parts in total of cement and expansion material in the grout composition. If it is less than 30 parts, sufficient fluidity may not be obtained, and if it exceeds 50 parts, sufficient durability may not be obtained.

  The construction method using the grout mortar of the present invention is not particularly limited.For example, the concrete deterioration portion is suspended, the reinforcing bars are rusted, the primer treatment is performed, the mold is installed, Examples thereof include a method of filling the frame with the grout mortar of the present invention and curing it.

  The grout mortar of the present invention, for example, not only repairs concrete deterioration parts under piers and harbors, but also subsidences and cracks on the surface of roads, sidewalks, treatment plants, and parking lots paved with asphalt or concrete. It can also be used to repair etc.

  EXAMPLES Hereinafter, although this invention is demonstrated concretely based on an Example, this invention is not limited to these.

  100 parts of cement, 5 parts of expansion material, and further 100 parts of cement and expansion material, 8 parts of powder resin, 0.5 part of basalt fiber with the length shown in Table 1, 4 parts of shrinkage reducing agent, water reducing agent A grout composition was prepared by blending 0.3 part, 0.02 part of antifoaming agent, and 180 parts of aggregate having an aggregate A / aggregate B mass ratio of 60/40. 40 parts of water is added and kneaded to 100 parts of the cement and the expansion material in the grout composition to prepare a grout mortar, the stationary flow value of the grout mortar, the amount of cure shrinkage, the compressive strength, the adhesion The strength and durability were measured and evaluated. The results are shown in Table 1.

<Materials used>
Cement α: Ordinary Portland cement, Commercial product cement β: Early strength Portland cement, Commercial product expansion material: Calcium sulfoaluminate-based expansion material, Commercial product powder resin: Acrylate ester-vinyl acetate-Versatic acid vinyl powder resin, commercial product Water reducing agent: Main component polycarboxylate, powdery, commercially available basalt fiber: Fiber diameter 10 μm, convergence type, manufactured by Kanae, trade name “Basart Fiber”
Shrinkage reducing agent: lower alcohol alkylene oxide derivative system, powder, commercial product antifoaming agent: main component silicone system, powder, commercial product aggregate A: natural sand from Himekawa, Niigata, grain size less than 1.2 mm, specific gravity 2 .62
Aggregate B: natural sand from Himekawa, Niigata Prefecture, particle size 1.2-4mm, specific gravity 2.65

<Measurement and evaluation method>
Static flow value: according to JIS R 5201-1997, when no falling motion is given 15 times, evaluation of fresh properties at 20 ° C. Curing shrinkage: according to JIS A 1171 “Testing method for polymer cement mortar” A test specimen was prepared, and the drying shrinkage at 28 days of age was measured at 20 ° C. and 60% according to JIS A 1129 “Method for length change of mortar and concrete”. Compressive strength: Under water according to JIS R 5201-1997 Adhesion strength evaluated at age of 28 days of curing: According to JHS 416 “Adhesion with mortar cross-section restoration material / concrete”, the concrete surface is filled with 1 cm thickness, and adhesion strength of 28 days at 20 ° C. and 85% Durability measured with a Kenken type tensile tester: A test specimen was prepared by filling a 30 × 30 cm concrete plate with 1 cm thick grout mortar. The cured specimen was placed outdoors, and the number of days until crack initiation and the degree of cracking were evaluated. More than the number of days until the cracks occur 60 days, ○ what crack width is less than 0.1mm, the number of days those of 0.2m m or less under more than crack width is the 0.1mm in less than 60 days △, number of days The crack width is 0 in less than 60 days. What exceeded 2 mm was set as x.

  From Table 1, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

  100 parts of cement alpha, 100 parts of cement and the amount of expansive material shown in Table 2, and 8 parts of powder resin, 0.5 part of basalt fiber 6 mm in length, shrinkage, for a total of 100 parts of cement and expansive material A grout composition was prepared by blending 4 parts of a reducing agent, 0.3 part of a water reducing agent, 0.02 part of an antifoaming agent, and 180 parts of an aggregate having a mass ratio of aggregate A / aggregate B of 60/40. Except for this, the same procedure as in Example 1 was performed. The results are shown in Table 2.

  From Table 2, it can be seen that the grout mortar of the present invention has high fluidity, little curing shrinkage, high strength expression, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and 100 parts of cement and expansion material in total, the amount of powder resin shown in Table 3, 0.5 part of basalt fiber with a length of 6 mm, 4 parts of shrinkage reducing agent, water reduction Example 1 except that 0.3 part of an agent, 0.02 part of an antifoaming agent, and 180 parts of an aggregate having an aggregate A / aggregate B mass ratio of 60/40 were blended to prepare a grout composition. As well as. The results are shown in Table 3.

  From Table 3, it can be seen that the grout mortar of the present invention has high fluidity, little curing shrinkage, high strength expression, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansive material, and further 100 parts of cement and expansive material, 8 parts of powder resin, 6 mm long basalt fiber in the amount shown in Table 4, shrinkage reducing agent 4 parts, water reducing agent 0 .3 parts, antifoaming agent 0.02 parts, and aggregate A / aggregate B mass ratio 60/40 of the aggregate of 180 parts, the same as in Example 1 except that the grout composition was prepared. went. The results are also shown in Table 4.

  From Table 4, it can be seen that the grout mortar of the present invention has high fluidity, little curing shrinkage, high strength expression, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and further 100 parts of cement and expansion material, 8 parts of powder resin, 0.5 part of basalt fiber with a length of 6 mm, amount of shrinkage reducing agent shown in Table 5 and water reduction Example 1 except that 0.3 part of the agent, 0.02 part of the antifoaming agent, and 180 parts of the aggregate with an aggregate A / aggregate B mass ratio of 60/40 were prepared to prepare a grout composition. The same was done. The results are shown in Table 5.

  From Table 5, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and further 100 parts of cement and expansion material, 8 parts of powder resin, 0.5 part of basalt fiber with a length of 6 mm, 4 parts of shrinkage reducing agent, amounts shown in Table 6 As in Example 1, except that 0.02 part of the water reducing agent, 0.02 part of the defoaming agent, and 180 parts of the aggregate having an aggregate A / aggregate B mass ratio of 60/40 were blended to prepare a grout composition. went. The results are shown in Table 6.

  From Table 6, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and 100 parts of cement and expansion material in total, 8 parts of powder resin, 0.5 part of basalt fiber with a length of 6 mm, 4 parts of shrinkage reducing agent, 0.3 part of water reducing agent Parts, an antifoaming agent in the amount shown in Table 7, and 180 parts of aggregate with a mass ratio of aggregate A / aggregate B of 60/40, and the same as in Example 1 except that a grout composition was prepared. went. The results are shown in Table 7.

  From Table 7, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength expression, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and 100 parts of cement and expansion material, 8 parts of powder resin, 0.5 part of basalt fiber with a length of 6 mm, 4 parts of shrinkage reducing agent, 0. Example 1 except that 3 parts, 0.02 part of antifoaming agent, and aggregates in an amount shown in Table 8 having a mass ratio of aggregate A / aggregate B of 60/40 were prepared to prepare a grout composition. As well as. The results are shown in Table 8.

  From Table 8, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

  100 parts of cement α, 5 parts of expansion material, and 100 parts of cement and expansion material, 8 parts of powder resin, 0.5 part of basalt fiber with a length of 6 mm, 4 parts of shrinkage reducing agent, 0. 3 parts, 0.02 part of antifoaming agent, and 180 parts of aggregate with a mass ratio of Aggregate A / Aggregate B of 60/40 were prepared to prepare a grout composition. Was carried out in the same manner as in Example 1 except that grout mortar was prepared. The results are shown in Table 9.

  From Table 9, it can be seen that the grout mortar of the present invention has high fluidity, little cure shrinkage, high strength development, high adhesion strength to concrete, and excellent durability.

  The grout mortar using the grout composition of the present invention has excellent fluidity, small change in length, excellent durability, and excellent adhesion strength to concrete, etc. It can be suitably used for repair work, in particular, repair of cross sections around bridges, repair of concrete parts of harbor structures, and filling and repairing pavements such as asphalt and concrete on roadways and sidewalks.

Claims (3)

Portland cement, expansive material, re-emulsifying powder resin, converging melt-spun basalt fiber bundled with single fibers with fiber length of 2-15 mm and fiber diameter of 2-50 μm , shrinkage reducing agent, water reducing agent, Containing foaming agent and aggregate , expandable material is 1-20 parts for 100 parts of Portland cement, re-emulsifying powder resin is melted for 3-20 parts for a total of 100 parts of cement and expandable material Spun basalt fiber is 0.1 to 10 parts for 100 parts of Portland cement and expansion material, shrinkage reducing agent is 0.3 to 7 parts for 100 parts of cement and expansion material, water reducing agent is cement. And 0.05 to 3 parts in terms of solid matter for a total of 100 parts of the expansion material, 0.01 to 0.1 part for the defoaming agent to a total of 100 parts of cement and the expansion material, and the aggregate is Portland cement And 100 parts of expanded material Is 150 to 300 parts of Te, grout composition. Claim 1 Ri name by mixing the grout composition and water according to, 30 to 50 parts per 100 parts of the amount of water with cement grout composition expansive grout mortar. A grout method using the grout mortar according to claim 2 .