JP3480528B2 - Suspension manufacturing method - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a suspension, and more particularly to a method for improving soft ground, preventing spring water, and strengthening rock and concrete. The present invention relates to a method for producing a suspended grout which is used by filling a grout or a void. 2. Description of the Related Art Conventionally, cracks and voids are filled with suspended grout in which a cement powder is dispersed in water for improving soft ground, preventing spring water, and strengthening rock and concrete. Grout injection method is applied. The grout used in the grout injection method is generally a suspension in which a mixed powder of portland cement, clay mineral, blast furnace slag, fly ash and the like is dispersed in water. [0003] Conventionally, mixed powder for grout has been mixed and dispersed in a predetermined amount of water by a mixer to produce a suspended grout. As a mixer used for producing the suspension grout, there is a mixer in which a grout mixer and a pump are combined into one, or a mixer which also serves as a pumping machine such as a jet mixer or a canif mixer. In the grout mixer, a rotating shaft with rotating blades is attached to a tank, and the grout is kneaded by vortex generated by the rotating blades and convection in the tank. For bentonite and air mortar, those having a high rotation speed of a maximum of about 10,000 rpm are used. [0004] By the way, when grout is injected into concrete cracks or voids in the ground, in order to easily inject the grout, the dispersed particles in the grout must be made of soil particles or cracks. It is necessary that the particle diameter has such a size as to easily pass through the gap. However, a suspended grout obtained by dispersing a mixed powder of portland cement, clay mineral, and the like, which has been conventionally used for grout, in water with the above-mentioned mixer, in a state of being suspended in water, Actually, the respective powder particles aggregate with each other to form a large particle mass. The particle size of each powder used in grout is measured in a state close to complete dispersion, so the value of coarse particles is small, but in a suspended grout in which this is dispersed in water, the powder aggregates As a result, a large amount of coarse particle mass is generated. For this reason, in the conventional suspension grout, the aggregates are collected in a flow path such as a crack or a void near the injection port, and clogging occurs in a sudden change in the flow path width. As a result, grout cannot often penetrate into the interior. For these reasons, suspended grout could not be injected into the fine-grained sandstone layer, and ground improvement and bedrock strengthening could not be performed. By the way, in the conventional suspension grout production method, even if the mixture is stirred by a high-speed mixer, the particle mass formed by agglomeration of the powder in the grout is not loosened, and agglomerated coarse particles remain. Could not be injected into quality rock. [0007] Generally, it is said that the maximum particle size of cement used for grout for injection is 1/3 of the crack width and about 1/10 of the particle size of the stratum. Thus, the reason why the width of the interval through which grout penetrates is set to be much larger than the maximum particle diameter of cement is considered to be mainly due to the generation of the aggregated particle mass. [0008] Therefore, it can be said that if the aggregates having a large diameter are loosened, the permeability of the grout to the narrow space is improved. The present invention has been made in view of the above-mentioned conventional circumstances, and can obtain a strong dispersion promoting action for loosening agglomerated particles of powder, and therefore has excellent permeability and injection efficiency. It is an object of the present invention to provide a method for producing a suspension that can easily produce a high suspension grout. [0010] According to a first aspect of the present invention, there is provided a method of producing a suspension, wherein a powder containing cement as a main component is dispersed in water to produce a suspension grout. In the method,
By adding ultrasonic vibration in a mixer after or while adding the surfactant to loosen agglomerates of the powder, substantially no particles having a particle size of 12 μm or more are present. It is characterized by producing a suspension grout . [0011] Immediate Chi, the present inventors have found that permeability to loosen the agglomerated particles a mass of grout powder, injection results to diligent research to produce a superior suspension system grout efficiency, the suspension system grout It has been found that, when vibration is applied by ultrasonic waves during the production of, the aggregates of the cement-based powder are loosened, coarse particles disappear, and the permeability of the grout is dramatically improved. Also, at this time, if a surfactant that promotes dispersion of the powder in the grout is used, loosening of the agglomerated powder becomes easier, thereby increasing the injection amount and further improving the permeability. I found that I can do it. The present invention has been completed based on the above findings. Hereinafter, the present invention will be described in detail. The gist of the present invention is to disperse the powder for grout in water to produce a suspension, and to disperse the agglomerates of the powder particles, to remove the powder by a conventional rotary blade. together provide a stronger vibration than dispersing action, by the use of the interfacial active agent, and is characterized in that the particle size 12μm or more of the particles to produce a suspension grout substantially absent. Specifically, an ultrasonic wave is used. This vibration is desirably applied during and / or after stirring by the rotating blades because of its high dispersion efficiency. In addition, by using a surfactant that promotes dispersion during the dispersion treatment, the aggregated powder can be more effectively disintegrated, and the resulting grout can be increased in injection amount and permeated. Continuation time can be improved. Further, the time for applying the ultrasonic wave can be shortened. In the present invention, when applying vibration by ultrasonic waves, an ultrasonic transmitter having an output of about 10 to 2000 W may be used. In general, the method of the present invention comprises the steps of: mixing water and a powder for grout obtained by mixing cement or cement with clay mineral, blast furnace slag, fly ash, or the like;
For example, after stirring with a mixer at a speed of about 200 to 800 rpm for about 0.5 to 2 minutes with a water powder ratio of about 2 to 10 in a conventional manner, the obtained kneaded material is ultrasonically vibrated for about 0.5 to 5 minutes. It is carried out by applying a forced dispersion treatment for imparting. The boundary surface active agent, when the stirring process may be added to any of the forcible dispersion treatment, also may be used in premixed grout powder. The surfactants used include lignin sulfonates and derivatives thereof, oxycarboxylates, polyol derivatives, polycarboxylates, high condensates of formalin naphthalene sulfonate, condensates of melamine sulfonate formalin, alkyl allyl sulfones Acid polymer,
Chemical admixtures containing, as main components, highly condensed triazine compounds, methylol melamine condensates, nitrogen-containing sulfonates, amino sulfonates, and the like. The amount of the surfactant to be added is appropriately adjusted in view of the looseness of the agglomerated powder and the injection properties. In general, the amount is preferably 1 to 3% by weight based on the grout powder. preferable. According to the present invention, by forcibly dispersing by ultrasonic vibration,
The coarse particles of the agglomerates of the powder generated in a large amount in the dispersion system are effectively loosened and disappeared. As a result, a large amount of grout smoothly penetrates into the fine-grained sandstone rock and ground, which could not be injected due to the presence of coarse particles of agglomerates, even in the conventional grout using cement made of fine particles. Become like Furthermore, in order to reduce bubbles in grout,
The filling property of the grout after permeation becomes good. The method of the present invention is particularly effective for producing cement milk grout, and is also effective for improving the separation resistance of grout. [0022] In the present invention, it is possible to reduce the amount of the surfactant used for improving the dispersibility at low surfactant usage, it is possible to obtain a more excellent improving effects. The present invention will be described in more detail with reference to the following Examples and Comparative Examples. However, the present invention is not limited to the following Examples unless it exceeds the gist thereof. Comparative Example 1 An ultra-fine cement (Fine Hard) (maximum particle diameter: 12 μm) manufactured by Mitsubishi Materials Corporation was kneaded at a ratio of water cement of 6 with a hand mixer at 500 rpm for 30 seconds, and then the output during operation was kneaded. The beaker containing the kneaded material was immersed in a 150 W ultrasonic cleaner for 60 seconds to perform a forced dispersion treatment. With respect to the obtained suspension grout, the particle size distribution of the dispersed particles and the dispersibility and permeability were examined by the following method. The results are shown in Table 1. [Particle Size Distribution] The particle size distribution was measured by a laser diffraction type particle sizer in a state where forced dispersion treatment was not performed by ultrasonic waves or the like using water as a medium. [Dispersibility] The grout was placed in a graduated cylinder, and the sedimentation volume was measured over time to evaluate the dispersibility. [Permeability] 100 ml of grout is put into a beaker and 200 ml
Standard sand for cement strength test (particle diameter 0.1-0.3mm) filled into a 200mm thick cylindrical separating funnel
, And the depth of penetration was measured. Comparative Example 2 A grout was prepared in the same manner as in Comparative Example 1 except that the forced dispersion treatment was not carried out, and the particle size distribution, dispersibility and permeability were similarly examined. The results are shown in Table 1. As is clear from Table 1, after kneading with a mixer, by forcibly dispersing with ultrasonic waves, aggregated coarse particles are reduced, and dispersibility and permeability to a sand layer are dramatically improved. In particular, in the forced dispersion processing using ultrasonic waves,
The tendency is remarkable. [Table 1] Comparative Example 3 An ultrafine cement (Finehard) (maximum particle diameter: 12 μm) and kaolin (maximum particle diameter: 5 μm) manufactured by Mitsubishi Materials Corporation were mixed at equal weights to obtain a powder for injection, and a water-powder ratio was determined. After kneading at a rate of 6 with a hand mixer at 500 rpm for 30 seconds, grout was obtained by performing forced dispersion treatment in the same manner as in Comparative Example 1, and the particle size distribution, dispersibility, and permeability were examined in the same manner. It was shown to. Example 1 In Comparative Example 3 , before starting kneading with a hand mixer,
The same procedure was performed except that 3% by weight of a naphthalenesulfonic acid-based surfactant (Kaio's admixture “Mighty 100” manufactured by Kao Corporation) was added to the powder, and the particle size distribution, dispersibility, and permeability were similarly determined. And the results are shown in Table 2. Comparative Example 4 Comparative Example 3 was carried out in the same manner as in Comparative Example 3 except that the forced dispersion treatment was not carried out. Similarly, the particle size distribution, dispersibility and permeability were examined. The results are shown in Table 2. As is evident from Table 2, after kneading with a mixer, by forcibly dispersing with ultrasonic waves, agglomerated coarse particles are greatly reduced, and dispersibility and permeability to a sand layer are dramatically improved. Further, when a surfactant that promotes dispersion of the powder is used in combination, the tendency becomes remarkable. [Table 2] As described above in detail, according to the method for producing a suspension of the present invention, it is possible to disperse powder containing cement as a main component in water to produce a suspension grout. By effectively loosening agglomerates of powder particles, the formation of coarse particles can be prevented, and a suspension grout having excellent uniform dispersibility can be obtained. Therefore, the method for producing a suspension according to the present invention prevents the production of coarse particles in which powder particles are aggregated, when producing a suspended grout by dispersing cement-based powder in water. A suspension grout having excellent permeability and high injection efficiency can be produced. The suspension grout produced by the method of the present invention is excellent in permeability, so that it can be easily poured into soft ground, fine cracks or voids in rock or concrete, which could not be poured with conventional suspension grout. It is possible to effectively infiltrate the ground, rock, and concrete, and it is possible to strengthen and improve the ground. [0036] In particular, for use of a surfactant, it is possible to obtain a superior effect.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification code FI C09K 17/48 C09K 17/48 PC09K 103: 00 103: 00 (56) References JP-A-59-109613 (JP, A) JP-A-62-225235 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09K 17/10, 17/44, 17/48 B01F 3/12, 11/02 B28C 5 / 48

Claims (1)

(57) [Claim 1] In a method for producing a suspension grout by dispersing powder containing cement as a main component in water to produce a suspension grout, after adding a surfactant. Or while adding the mixer
A suspension grout in which particles having a particle size of 12 μm or more are substantially absent by applying ultrasonic vibration within the medium to loosen agglomerates of the powder. Manufacturing method .