KR100288940B1 - Method of paving cement concrete using waste calcium carbonate - Google Patents

Abstract

The present invention relates to a method for utilizing waste lime, which is a kind of industrial waste, as a base material in cement concrete pavement, and mixing and stirring waste lime 30 to 500 kg / 1 m3 with 80 to 160 kg / 1 m3 of water. fair; The slump value is mixed with the aggregate of 1300-2000kg / 1㎥ of aggregate which passes 90-100 at the basis of the percent by weight in cement 220-350kg / 1㎥ and 40mm sieve and 0-30% in the 5mm sieve. Forming a cement concrete mixture having a 0 cm and a compacted state reference compressive strength of 150 to 300 kg / cm 2; Laying and compacting the cement concrete mixture of the electrical process on a substrate; Sprinkling water within 1.2 kg per m 2 within 1 hour after compaction on the surface of the compacted substrate in the electrical process; And to provide a cement concrete paving method using waste lime, including the step of laying, compacting and curing the surface layer according to a conventional method on top of the base layer formed in the electrical process, environmental protection and The economic effect of waste recycling is enormous.

Description

Method of paving cement concrete using waste lime {Method of paving cement concrete using waste calcium carbonate}

The present invention relates to a method of using waste lime, which is a kind of industrial waste, as a base material in cement concrete pavement.

Waste lime is a residue left after refining soda ash and silicate from limestone or limestone, which contains harmful substances such as lead and cadmium, which may cause environmental pollution. Therefore, it cannot be used as a landfill or cover material. There is a problem that the economic burden is too high because it costs about 80,000 won per t to treat it as industrial waste. In addition, since the size of the waste lime is very small, as the particle size is 50 mesh or less, when it is stored in a yard, there is a problem of polluting air and streams by blowing in the wind or by rain.

This industrial waste waste lime, even in the Nam-dong Industrial Complex in Incheon, caused serious environmental problems due to the accumulation of about 3 million tons of waste lime in the yard as of January 1999 and the generation of hundreds of thousands of tons of waste lime annually. I'm doing it.

In order to solve this problem, studies on using waste lime as a material for cement concrete or asphalt concrete pavement have been conducted, but due to the characteristics of the waste lime being too small and the water content is too high, it is not suitable for use as a material for such pavement. It has been considered.

In more detail, when applied to asphalt concrete, waste lime has a specific gravity of 2.50 or less, so when used as a pavement material for asphalt concrete, the quality of pavement is deteriorated. It is known that it is not economical due to high fuel costs and cannot be used for asphalt concrete because it is likely to become agglomerate when drying the waste lime in a gel state.

In the application to cement concrete, the waste lime is mainly in the gel state, so it is difficult to add it to the mixer, and the bleeding becomes larger when the waste lime is mixed with ordinary (slumped) cement concrete. Accordingly, there is a problem in that the light weight of the waste lime lime rises up, so that the latans are large.

Rhetans refers to the formation of a film on the surface of cement concrete where the low specific gravity of the cement concrete mixture rises due to bleeding. Upon contact, the waste lime powder becomes particulate and floats in the air like dust, causing serious air pollution.

It is an object of the present invention to provide a method that can utilize waste lime as a material for cement concrete pavement, away from the conventional perception of the utilization of waste lime.

More specifically, the present invention is used by mixing the waste lime to cement concrete, but the slump value of the concrete mixture is 0cm and laid by the roller compact to eliminate the bleeding phenomenon, while the cement concrete mixed with the limestone has a surface layer It is used for the base layer of cement concrete pavement by avoiding direct contact with the wheels and by forming the non-water-permeable base layer in which the waste lime acts as a filler for the pores formed in the base layer. The purpose is to utilize as a material.

Hereinafter, the configuration and operation of the present invention will be described in detail.

In order for waste lime to be used as a material for cement concrete pavement, the following conditions must be met:

First, a plan must be prepared to easily inject waste lime into the mixer.

Waste lime has a high water content and is expensive to dry the moisture contained therein, and can not be used unless it is broken finely because it becomes agglomerated by heating. Therefore, waste lime cannot be used as a packaging material unless a method for easily injecting such waste lime into the mixer is provided.

Second, concrete layer mixed with waste lime is not used for surface layer because it is necessary to avoid contact of wheel tube.

Since the particles of waste lime are very small, less than 50 mesh, when the concrete layer mixed with the waste lime comes into direct contact with the wheels, the waste lime particles contained in the concrete may be broken and float in the air, causing air pollution.

Third, the slump of the concrete mixed with waste lime is set to 0 cm and laid out as a roller compaction, and the bleeding and the retardance phenomenon are prevented by allowing the waste lime to act as a filler for the voids formed during pavement.

The present invention satisfies all of the above conditions as a method of utilizing waste lime as a cement concrete pavement, the process of the present invention is as follows.

First step: preparing materials at the mixing ratio for compacted concrete for base

This process is to prepare materials for compacted concrete for substrates including waste lime at the following compounding ratio per 1㎥.

Water: 80 to 160 kg

Cement: 220 ~ 350㎏

Waste lime: 30 ~ 500㎏

Aggregate: 1300∼2000㎏

Cement concrete formed by this blending ratio is based on the slump 0cm, compressive strength (based on compaction state) 150 ~ 300㎏ / ㎠. In the aggregate, the aggregate passes 90 to 100 based on the percent by weight of the 40 mm sieve, and the aggregate passes through 0 to 30% in the 5 mm sieve.

Step 2: adding water to the waste lime and stirring

In the materials prepared in the above mixing ratio, 0.3 to 5 parts by weight of waste lime in 1 part by weight of water is added to a tank equipped with a stirrer to stir. At this time, it is preferable to add a dispersant (mixing agent) to the tank in order to increase the dispersing force. Determination of the input amount of waste lime is, for example, when the water content of the waste lime is 20%, when the mixture ratio of water and waste lime is 1: 2, when 200 kg of waste lime is blended with 100 kg of water, it is contained in the waste lime. Since there is 48 kg of water (40 kg of 48 kg is the weight of water functioned as water content in 200 kg of waste lime, the remaining 8 kg is the weight of water contained in 40 kg of waste lime added), the actual water mixed is 52 kg and waste lime Is 248 kg, and the total mixed amount is 300 kg.

3rd process: mixing materials

Mixing in the electric process It is a process of adding the remaining materials to the mixture of stirred water and waste lime. In the electrical process, the waste lime is mixed and stirred with water so that it is sufficiently diluted so that it can be easily mixed with other materials. In this process, reinforcing fibers may be added as necessary. As the reinforcing fibers, polypropylene, polyethylene, carbon fibers, steel fibers and the like can be used.

4th process: laying and compacting process

In the electric process, the asphalt concrete mixed with the Hunisha or the difficult installation is installed with manpower, fork-lane, biblet or other pavement. It is the process of compacting to more than 100% of.

5th process: watering process

This process is to spray water to remove the voids remaining on the surface and increase the adhesion of the surface layer after compaction of the ground compaction concrete. Spraying should be done within 1 hour after laying for base, and spraying quantity should be within 1.2kg per 1㎡.

6th step: Surface layer laying process

It is a process of depositing a surface layer on top of the base layer formed in the electrical process. As the surface layer, permeable or impermeable cement concrete is laid, compacted, and cured according to a conventional method to complete road paving.

On the other hand, since the base layer is made of impermeable, compacted compacted concrete, when the permeable concrete is laid on the upper part of the aggregate particle size different from that of the base layer, it is possible to totally drainage the pavement.

When permeable cement concrete is laid on the base for drainage pavement, it should be installed within 2 hours after compaction of the base compacted concrete, but the aggregate used is preferably a coarse aggregate whose maximum dimension is 19 mm or less. Depending on the 13mm, 10mm, 8mm, 6mm, etc. can be used, the particle size range is 90 to 100% pass on the basis of the percent by weight in the 19mm sieve, 0 to 30% pass in the 5mm sieve, 0-10% in the 2mm sieve Aggregate in the range should be used, and the Los Angeles wear rate should be less than 30%, but the mixing ratio should be as follows.

Water: 80 ~ 150㎏ / ㎥

Cement: 300 ~ 450㎏ / ㎥

Aggregate: 1450∼2000㎏ / ㎥

Admixture: Within 2% of cement usage

In the above formulation, the slump of cement concrete mixture should be 0cm, porosity 10-30%, permeability coefficient 20x10 ^-2 cm / sec or more, compressive strength 100-400㎏ / ㎠. Then, the cement concrete mixture is laid with a whisker, a machine, a manpower, etc., and compacted with more than 100% of the test specimens with a roller, and then cured with a vinyl and a curing cloth by a conventional method, and cured with a cutter. The polymer is sprayed with epoxy, acrylic, unsaturated resin or urethane.

Hereinafter, the present invention will be described based on Examples.

<Example>

The parking lot with an area of 100㎡ is packed and the strength is 210㎏ / ㎠ or more, 7cm of the total thickness of 10cm is used as the ground compaction concrete, but waste lime is used as the base material, and 3cm of the surface layer is made of drainage paving. The color is to be green.

(Step 1)

A tank capable of dilution was prepared, and 130 kg of water, 150 kg of waste lime, and 1 kg of a delayed water-sensitive dispersant were mixed and mixed with 1 m 3 of the compaction basis for the base compacted concrete. At this time, since the water content of waste lime is 35%, the water input is 60 kg, and the weight of waste lime is 220 kg.

(2nd step)

1,650 kg of aggregate passed through 100% of cement 270kg, 25mm and 15% in a 5mm sieve was mixed per 1m3 of the compacted concrete for the base to mixed waste lime mixed with water in the electric process.

(3rd step)

In the electric process, the mixed concrete is transported by a damp truck, laid out using a fork-lane, cleaned up by manpower, and then compacted with more than 100% of the test specimens with tantemola, and then sprayed onto the base compacted concrete within one hour. 50 kg of water was sprayed per m 2.

(4th step)

The permeable cement concrete mixture was laid on top of the ground compaction concrete sprayed in the electric process by using a fork crane, and smoothed out by manpower, and then compacted to more than 100% of the test specimens by using Laura and Compacta. At this time, the permeable concrete is mixed per 1m 3, water 110kg, cement 320kg, and the aggregate uses the maximum size of coarse aggregate 10mm, when the particle size analysis is passed 100% in 19mm sieve, 7% in 5mm sieve, 1.2% pass through 2mm sieve is 1,650 kg of aggregate of particle size distribution, green is used for pigment, 20 kg is used for delayed water-sensitive dispersant.

(5th process)

The permeable concrete layer laid and compacted in the electrical process was covered with vinyl after curing and cured. After 3 days, the vinyl was peeled off, and horizontal and vertical joints were installed at intervals of 5 mm with a cutaway.

(Step 6)

After grasping the dryness of the surface of the permeable concrete layer of the electric process, the green layer is mixed with 15% of the amount of epoxy used in the dry state, and 20% of the diluent is mixed with the epoxy to facilitate spraying. Spread evenly over the sieve and wrap it with vinyl or tape to prevent material from getting on the other part.

In this way, an impervious base layer was formed of cement concrete containing waste lime, and permeable cement concrete was installed on the upper portion thereof to complete the parking lot of the drainage pavement.

The porosity, compressive strength, and permeability coefficient of the drainage parking lot packaged according to the above embodiment were examined, and the results are shown in Table 1 below.

Slump (cm) Porosity (%) Compressive strength (㎏ / ㎠) Permeability coefficient (cm / sec) Substrate 0 - 247 - For surface use 0 22 251 5.7 * 10 For base substrate 0 - 210 or more - For base surface 0 10-30 210 or more 20 * 10 or more

As described in detail above, the cement concrete pavement according to the present invention forms a base layer in pavement such as a road or a parking lot by using waste lime, and can use waste lime which is industrial waste, thereby protecting the environment and recycling waste. The economic effect of this is huge.

In addition, since the cement concrete base layer using waste lime has sufficient compressive strength and becomes an impermeable impermeable layer, when the permeable cement concrete pavement is formed on the upper part thereof, the pavement is generally drained, so the present invention is applicable to general roads and highways requiring drainage. It is a very useful thing to do.

Claims (4)

Mixing and stirring 30 to 500 kg / m 3 of waste lime in 80 to 160 kg / m 3 of water; The slump value is 0cm by mixing 1300-2000kg / m3 of aggregate, which passes 90-100 based on the percentage of the weight of the cement through 220-350kg / m3 of cement and 40mm sieve, and 0-30% in 5mm sieve. Forming a cement concrete mixture having a compaction state reference compressive strength of 150 to 300 kg / cm 2; Laying and compacting the cement concrete mixture of the electrical process on a substrate; Sprinkling water within 1.2 kg per m 2 within 1 hour after compaction on the surface of the compacted substrate in the electrical process; Cement concrete paving method using waste lime, including the step of laying, compacting and curing the surface layer according to a conventional method on top of the base layer formed in the electrical process. The method of claim 1, wherein the surface layer is a permeable cement concrete layer. The aggregate used in the permeable cement concrete layer has a coarse aggregate maximum dimension of 19 mm or less, and the grain size ranges from 90 to 100% based on the percentage of weight passed in a 19 mm sieve, and 0 to 30% passes in a 5 mm sieve, and 2 mm. Cement concrete pavement method using waste lime, the aggregate of which ranges from 0 to 10% in sieve, and the Los Angeles wear rate is within 30%. The mixing ratio of water-permeable cement concrete according to claim 3, wherein the mixing ratio of water-permeable cement concrete is water: 80-150 kg / m 3, cement: 300-450 kg / m 3, aggregate: 1450-2000 kg / m 3 and admixture: within 2% of the amount of cement used. A cement concrete pavement method using waste lime, which has a slump of 0 cm, a porosity of 10 to 30%, a permeability of 20 × 10 ⁻² / sec or more, and a compressive strength of 100 to 400 kg / cm 2.