KR100362013B1 - Liquified fly-ash mortar stabilization - Google Patents

Abstract

The fluidized solidification composition of the present invention is a mixture of Portland cement 50-240kg / ㎥, fly ash 280-700kg / ㎥, sand 1000-1400kg / ㎥, water 320kg / ㎥ and 8-83kg / ㎠ It has a compressive strength and a slump of 25 ± 1 cm.

In addition, Portland cement 50-240㎏ / ㎥, fly ash 280-700㎏ / ㎥ and sand 1000-1400㎏ / ㎥ are mixed by dry bibeam method and compressive strength of 8-83㎏ / ㎠ and 25 ± 1 It has a slump value of cm.

This fluidized solidifying composition is used as a filler when filling various underground cavities, and can solve resource rehabilitation and environmental problems by using a large amount of fly ash, which is an industrial by-product, and is economical because it replaces portland cement as a binder. Since it does not need to maintain high fluidity, it can be effectively used as a non-structural member filling material for various underground.

Description

LIQUIFIED FLY-ASH MORTAR STABILIZATION}

The present invention is carried out after drilling for investigation of hollow horizontal cavity or abandoned mine of abandoned mine, hot spring water or drinking water, agricultural water development and mine development investigation which occur after horizontal drawing dismantling of pipes in underground cavity road or various underground burial pipes. The present invention relates to a fluidized filling solidifying composition that can be effectively used for non-structural members such as ground voids and cavities such as underground subcavities and bridge alternating lower parts for burying abandoned waste holes.

If the underground cavity is left as it is, there is a risk of various accidents due to ground displacement or settlement by underground depression.

Therefore, in order to prevent this, a filling method using cement-injected solids, a fluidized soil in which cement is mixed with local soil, or a method using a solid-filled filler filled with bentonite and clay is commonly used.

However, since cement injection solids use a large amount of cement, there is a problem of dissolution of calcium ions in contact with groundwater and strength and economics. There is a problem in terms of adhesion and strength with the base material due to the shrinkage of the solid body afterwards. Bentonite and clay solids have good filling effect due to the expansion of bentonite, but they are mixed with cement at the same time.In order to solve the problem of causing abnormal quality of the solidified injection by the early reaction in the reaction with cement, two-component injection or mixing There is a problem that the improvement of the process is required.

In addition, once the cavity is filled with the material, its strength is so high that it is difficult to re-excavate.

In addition, the characteristics required as a filler for underground cavities are to reduce the resistance due to the friction of fluid movement in the pressure pipe during long distance pipe conveyance, and to maintain the fluidity for a long time when the long distance movement is necessary. Strength control may be required to facilitate this. In addition, the strength and strength characteristics of the same level as Jisan (地 山) is sometimes required.

On the other hand, coal-fired power plants that use coal-free coal usually require about 2 tonnes of coal for 1kw of production, and when burned, various types of ash (cinder ash, bottom ash, fly ash) within an average of about 12% are produced. Fly ash accounts for about 80-85% of the time. However, fly ash quality varies depending on the combustion mechanism, but in general, the quality is not constant depending on the type of coal, the combustion conditions of the boiler, and the type of dust collector. It has been refined by other methods and used in admixture, injection material, and fly ash cement of Portland cement, but its recycling rate is lower than that of foreign countries.

Accordingly, the present invention is to solve the above problems and to provide a filler that is easy to re-excavate in the future as a composite of the high-mobility of conventional Portland cement and hula ash.

In the present invention, as a result of reviewing the problems caused by the conventional filling materials, the use of cement is used by using a large amount of fly-ash as a binder as a by-product waste from the coal-fired power plant. Reducing environmental waste while reducing the leaching of calcium ions and improving the utilization rate of the plant headquarters (ash = ash pond), the biggest problem of thermal power plant operation in Korea, where the recycling rate is only 20-30%. The present invention has been developed with the idea that it can contribute to the extension.

Hereinafter, the present invention will be described in detail the configuration and operation as a means for solving the above problems.

The fluidized solidification composition according to the present invention is a mixture of Portland cement 50-240kg / ㎥, fly ash 280-700kg / ㎥, sand 1000-1400kg / ㎥, water 320kg / ㎥ and 8-83kg / ㎠ It is characterized by consisting of a high flow cement composite having a compressive strength of 25 ± 1 cm slump (slump) value.

In addition, materials other than water in the above-mentioned constituent materials may be blended by dry bibim method and packaged in a bag or the like in advance. The fluidized solidified composition thus packaged can be simply delivered to a site such as a construction site, and mixed with water in the site to be used as a filler.

If the cement content is less than 50 kg, the mixing property with fly ash is not good, and the strength is lowered.

When the fly ash is less than 280kg, the strength is lowered and the fluidity is lowered. When the fly ash is more than 700kg, the amount of cement is increased compared to the fly ash, so the strength is improved, but the cost is increased.

If the sand is less than 1000 kg, the strength is lowered. If the sand is more than 1400 kg, the cost is increased. In some cases, a function can be added by using a admixture such as a water reducing agent or a foaming agent.

Fly ash is generally a glass sphere containing some crystalline material and some carbon, and its particle size is in the range of 0.5-100㎛, ranging in size from medium to coarse clay, and the powder level is 3000cm2 / In and around g, the specific gravity is 1.9-2.4, which is about two-thirds of the specific gravity of cement. When contained in cement, calcium silicate hydrate (CSH) reacts with calcium ions (Ca ⁺⁺ ) generated by hydration and silica (SiO ₂ ) and alumina (Al ₂ O ₃ ) eluted from fly ash. = Calcium Silicate Hydrorate) or Calcium Aluminate Hydrorate (CAH) is formed by the pozzolan activation reaction and solidifies over a long period of time to develop strength. In the present invention, by using the fly ash as a binder of the fluidized composite solid in large quantities by replacing some of the existing cement, the use of cement in Portland is reduced, thereby forming a highly flexible composite which does not need compaction as a filling material for the underground cavity. Characterized in that.

Therefore, the flowable solidified composition according to the present invention has problems such as when the filling amount of the underground cavity is small, the filling of the closed pores of the depth, or the scattering of the small amount of work locally is difficult to cope with the transportation of materials or the transportation is poor, and so on. If present, the filler of the present invention can be prepared by wrapping the packaging by dry bibim and simply pouring water on site, and filling can be made immediately, and when filling for refilling the pipe such as water supply, a pigment with pigment is added to the filler of the present invention. It is characterized by being able to respond easily when re-excavated at the time of post maintenance by construction.

In general, in case of underground cavity filling, there are many cases that require long distance pipe conveying by central plant according to local conditions. Cement fluid composition loses its fluidity according to the time of transporting distance, transporting time, on-site waiting time, etc., so that the inside of the transport pipe is blocked by scaling inside the pipe, which may interfere with work or deteriorate quality due to material separation. As a result, the slump-flow value generally needs to maintain fluidity around 500 mm (when ψ10x20 cm is used). In actual work, however, it is better to work with fluidity of more than 620mm. In general, when re-excavation is required in the future after the filling of the cavity, manpower work is possible at 5 kg / ㎠ or less in general soils, and equipment excavation work is possible at about 10-20㎏ / ㎠.

In this example, the specimens were tested by setting the strength of re-excavation easily, and the results are as follows. The power plant fly ash used a refined fly ash of B thermal power, and slump measurement and slump hollow test were performed by the KSF 2402 method. And the application of the present invention is not limited to the examples.

In the test examples, the compressive strength, material properties, etc. in the indoor test are described.

Table 1. Formula list (unit: kg)

Table 2. Compressive strength test result (sample size 5cm x 5cm x 5cm) (unit: ㎏ / ㎠)

Table 3 Material Properties (1)

Table 4. Material properties (2)

Here, the permeability coefficient (透水 係數) represents the degree of penetration of water, and according to the above table, it can be seen that the effect of significantly preventing the penetration of water.

The fluidized solidification composition as a high-flow cement composite of the present invention as used as a filler is used for the filling of various underground facilities, underground pipe lower charging or joint filling of the temporary forced beam drawing hole in the pipeline or underground wall construction site, groundwater It is possible to solve resource rehabilitation and environmental problems by using a large amount of industrial by-products, pulley ash, when filling various underground joints such as waste air filling to prevent contamination of the soil. Since it does not require high fluidity, it can be effectively used as a non-structural member filling material in various basements, and it is easy to use a filling material manufactured by dry bibimbly in a construction site with poor working conditions or poor logistics transportation. Since it can be poured immediately by adding water, it has excellent workability and convenient strength adjustment for various applications.

In addition, since the strength can be adjusted, re-excavation is easy.

In addition, the fluidized solidification composition according to the present invention has an excellent effect that can be used in construction by simply transported to the field by being prepared by mixing and packing in a bag or the like by the dry bibim method.

Claims (2)

Portland cement 50-240㎏ / ㎥, fly ash 280-700㎏ / ㎥, sand 1000-1400㎏ / ㎥, water 320㎏ / ㎥ and mixed with 8-83㎏ / ㎠ compressive strength and 25 ± 1㎝ A fluidized solidifying composition comprising a high flow cement composite having a slump value. Portland cement 50-240㎏ / ㎥, fly ash 280-700㎏ / ㎥, sand 1000-1400㎏ / ㎥ are mixed by dry bibeam method and compressive strength of 8-83㎏ / ㎠ and 25 ± 1㎝ A fluidized solidifying composition comprising a high flow cement composite having a slump value of.