KR100567399B1 - Artificial fill materials for construction using industrial wastes - Google Patents

Abstract

The present invention is to provide an artificial fill material for construction and construction, characterized in that it comprises a natural soil material, and at least one reinforcing material selected from the group consisting of coal ash, waste concrete and slag.

According to the present invention, a natural soil material is mixed with at least one reinforcing material selected from the group consisting of coal ash, waste concrete and slag, and the artificial landfill material for construction workers has a liquid limit, plasticity index, Equal or superior effect can be obtained in modified CBR, permeability coefficient, stability, wear rate, and sand equivalent. In particular, the permeability performance is improved compared to conventional landfill materials using only natural soil materials, so it can be applied more effectively as construction materials for construction works where drainage functions are important, such as various sports stadiums, and are relatively expensive and have limited harvesting. By replacing some of the requirements with coal ash, waste concrete or slag generated as industrial by-products, it is possible to obtain the effects of waste recycling, conservation of the natural environment and prevention of environmental pollution.

Description

ARTIFICIAL FILL MATERIALS FOR CONSTRUCTION USING INDUSTRIAL WASTES}

The present invention relates to artificial soil materials for construction works, and more specifically, to natural ash materials, coal ash, waste concrete, or slag generated as industrial by-products in decommissioning works of various power plants, incinerators, various building structures, and various metal smelting processes. It relates to a new artificial landfill material used for construction.

Construction is a series of activities that create and build buildings and facilities. It is divided into construction works that build buildings and structures, civil works that are newly made by repairing land and rivers, and landscaping works that are carried out by subsidiary works of construction and civil works. do.

Various materials are used in this construction, and the most amount is consumed, and the materials used in various fields are basic materials.

Filling, landfilling, and covering each refers to the act of stacking soil, filling up soil, and covering the soil.However, landfilling and covering are often done through landfilling. It is common to regard the concept of filling as including landfilling and covering.

Soil materials have been used as soil materials in almost all fields until now. Generally, soil in construction works includes silt, clay, sand and gravel, and the classification of soil is KS F 2324 soil. It is represented as a combination of letters according to the engineering classification method of the symbols are as follows [Table 1] and [Table 2].

TABLE 1

First character Types of soil 2 characters Condition of soil  G S M C O Pt  Gravel Sand Silt (Mo Swedish) Clay Organic clay and silt Organic compressible organic soils -Assembly Soil W P M C  Well Graded Poorly Graded Non-plastic or low-plastic fine powder Fine-grained L H  Low Compressibility (LL <50) High Compressibility (LL> 50)

TABLE 2

Main division Classification code Representative Name  50% or less passed through 75㎛ sieve of granulated soil Gravel 4.75mm sieve 50% or less Clean pebbles GW Grain size distribution Good gravel or gravel sand mixture GP Particle size distribution Poor gravel or gravel sand mixture Gravel containing fine powder GM Silty gravel, gravel sand silt soil GC Clay gravel, gravel sand clay mix More than 50% of sand 4.75mm sieve passage Clean sand SW Particle size distribution good sand or sand mixed with gravel SP Particle size distribution Bad sand or gravel mixed sand Fine grained sand SM Silt sand, silt sand SP Clay sand, clay mixed sand  50% or more passed through fine grain 75㎛ sieve  Silt and Clay LL <50 ML Mineral clay, microfibers, fine silt and clay fines CL Low to medium mineral clay, gravel mixed clay, sand mixed clay, silt mixed clay, low viscosity clay OL Low plastic organic silt, organic silt clay  Silt and Clay LL〉 50 MH Mineral silt, mica or diatomaceous yarn or silt, elastic silt CH High-plastic mineral clay, viscous many clays OH Medium or High Plastic Organic Clay Organic soil Pt Other native soils such as peat

Filling works are carried out throughout the construction works such as civil works, building works, road works, and landscaping works. The filling materials are earth works, site facilities works, facility facilities work, designation and foundation work, road body, roadbed, frostbite prevention layer, auxiliary base, It is used for base works, site construction works, stop works, and landscaping pavement works.

In the construction work, drainage function is a very important matter to be considered in various ground compositions using landfill materials. If the drainage of rainwater and various waters flowing from the surface becomes poor, the settlement of the ground and the planting of the ground Growth, landfill leachate contamination can lead to several problems.

Therefore, during the construction of various construction projects, most of them require a material for excellent soil drainage in order to improve the drainage efficiency of rainwater and water, and to quickly drain surface water to the ground. Especially, it is paved with unpaved roads and permeable paving materials. It is a facility that works for various sports events such as roads, golf fields, grass fields, landfills, school grounds, tennis courts, baseball fields, soccer fields, etc., places to create greening systems such as roof gardens, and block floor layers for laying blocks. This is even more the case.

However, while most of the conventional landfill materials are made of natural materials, natural materials collection inevitably entails the problem of environmental destruction, and furthermore, the collection of natural aggregates in rivers, rivers, oceans and quarries is limited. As it is difficult to obtain the fill material that can show the drainage performance, the risk of secondary construction is always a problem, and development of alternative materials is urgently required.

Recently, some artificial soil materials are used as a countermeasure. However, most of them are simple substitutes for replacing only a small amount of existing soil materials, or mixed cement or solid materials with existing soil materials, or in the form of cement blocks or concrete blocks from the beginning. It is only manufactured and applied to fill, and construction waste materials such as waste concrete and waste asphalt are being considered, but there are still problems that cannot be solved in terms of conservation of natural environment and economic feasibility.

Therefore, it is urgent to develop a new material that can replace the existing soil material, in particular, a new fill material with excellent drainage function.

Meanwhile, coal ash, waste concrete, and slag are the largest industrial by-products generated annually. As of the end of 2004, about 6 million tons, 24 million tons, and 14 million tons are generated each year. Big.

Ash refers to the residues generated after the combustion or incineration material is burned and incinerated. In Korea, most of the ash is generated in the form of coal ash in large-scale thermal power plants. The main components of these ashes are mainly minerals such as SiO ₂ , Al ₂ O ₃ and Fe ₂ O ₃ , but they belong to recyclable materials, but they contain unburnt carbon, which is incidental, and irregular particle size distribution due to uneven particle size. This impedes technical application. Ash is generally classified into fly ash having a particle size of about 100 μm or less and bottom ash having a particle size of about 100 μm or more. Generally, about 80% of ash generated is fly ash and about 20%. Is a bottom ash.

Among these ashes, fly ash has been used in various fields such as cement admixtures, clay substitutes as cement raw materials, and lightweight aggregate production, and in particular, the use of concrete admixtures and cements as substitute raw materials is widely used. In addition, in the case of bottom ash, some parts are used in the manufacture of lightweight building materials, or fly ash is pulverized by pulverizing and then used in the field similar to fly ash, such as cement admixture and concrete admixture, but it is very insignificant in the degree and amount of practical use. It is true. In the case of coal ash, most of the thermal power plants, which produce about 40% of domestic electricity, are generated in large quantities because they use coal, and according to the government's long-term power supply plan, Emissions will continue to increase.

In addition, the waste concrete is mainly generated after crushing through a crusher in the field during the dismantling of large-scale facilities, generally coarse aggregates and fine aggregates are generated at a ratio of about 4: 1. In general, waste concrete has a low specific gravity and high absorption rate because of a large amount of waste mortar adhesion. Generally, the specific gravity is about 20 to 30% lower than the natural material, and the absorption rate is about 2 to 5 times higher.

Waste concrete is powdered to produce cement substitutes or recycled cement or used as recycled aggregates. However, in most cases, the amount of recycled concrete is lower than the performance required for the application. In the case of waste concrete, its generation will continue to increase in the future as the period of high growth in the last 40 years, especially the large-scale construction work since the 70s, and the life span expires, and redevelopment and reconstruction are activated.

Slag is an industrial by-product generated from various metal smelting processes, and its use and method are very similar to coal ash. Especially, in the case of finely powdered slag, it is widely used in cement and concrete fields. In the case of slag, a large amount of slag is generated in the steelmaking process of a global steelmaker.

As mentioned above, coal, waste concrete, and slag have been continuously increasing in recent years, and are used as reinforcement and substitute for cement admixtures, concrete admixtures, and various inorganic binders. It is used in the field of cement and concrete admixtures, and there is a lack of research on various other applications. In particular, there are very few studies on new utilization methods using coal ash, waste concrete, slag, etc. and synergistic effects in this case.

Therefore, recycling coal ash, waste concrete, slag, etc., which are inevitably generated in relation to the real life of humans, ensures stable power, promotes various development plans, preserves natural resources such as soil used in various construction works, In order to prevent the destruction of the natural environment due to improper disposal by illegal landfilling and dumping, it is a very necessary task.

Despite the necessity as described above, coal ash, waste concrete or slag was difficult to recycle due to characteristics such as unburned coal powder included in the components, conventional mortar attached to the surface, low specific gravity and high absorption rate.

An object of the present invention is to solve the above problems in the recycling of a large amount of industrial by-products of coal ash, waste concrete or slag, and at the same time, compared with the conventional soil material using only soil material, liquid limit, plasticity index, modified CBR To provide a new artificial fill material with equal or superior performance in terms of permeability, permeability, stability, wear rate and sand equivalent.

As a result of repeated studies to solve the above problems, the present inventors use only natural soil material by using it as an artificial landfill material for construction work including a reinforcement made of industrial ash by coal material, waste concrete, slag, etc. The present invention has been found to have equivalent or superior performances in liquid limit, plasticity index, modified CBR (califonia bearing ratio), permeability coefficient, stability, wear rate, sand equivalent, etc. compared to the case of filling material. It was.

That is, the present invention is to provide an artificial fill material for construction works, characterized in that it comprises a natural soil material, and at least one reinforcing material selected from the group consisting of coal ash, waste concrete and slag.

Hereinafter, the components used in the fill material of the present invention will be described in detail.

In general, as a fill material for construction works, a soil material in which one or more of clay, silt, sand, and gravel is mixed is used. The soil material for the fill is classified according to the KS F 2324 soil engineering method as described above. In the granulated soil having a 75 µm sieve fraction of 50% or less, the 4.75 mm sieve fraction of 50% or less is gravel and the 4.75 mm sieve fraction 50 If it is more than%, it is separated by sand. The specific gravity and absorption rate of coarse soils are correlated with each other, although they differ depending on the mother rock. That is, the specific gravity is large when water absorption is small, and the specific gravity is small when water absorption is large. In general, when the weathering of the granite soil is weathered, fine cracks are generated in the interior, which leads to a decrease in specific gravity and an increase in absorption rate. When such materials are used as soil materials for the construction work, the ground strength and modulus of elasticity decrease. It tends to increase dry shrinkage and lower durability against freeze-thawing. However, coal ash is a material produced after high-temperature combustion in a boiler or a furnace, and the specific gravity is not lowered due to weathering such as general soil, and the specific gravity is not reduced, but the melting of materials by high-temperature combustion, such as volcanic stone produced by volcanic eruptions. And because of the large number of pores generated inside the particles due to the explosion has a low specific gravity and high absorption rate porous particles are formed, but the strength is strong.

In addition, the waste concrete is generated by crushing or crushing concrete made of aggregate, sand, and cement, and the waste mortar made of sand and cement is attached to the existing aggregate. The absorption rate is increased due to the large number of pores formed in the mortar, and has almost the same performance as natural aggregate except for the attached mortar.

Slag is a molten non-ferrous component contained in the iron ore, coke and limestone charged in the furnace, SiO ₂ , CaO is an inorganic material, the main component is almost similar to coal ash.

Therefore, coal ash, waste concrete, and slag, which are generated through the above-described generation process, have a good side as a fill material for construction work other than natural soil material. In other words, the high water absorption increases water retention capacity by increasing water retention, so it is well suited to the function of soil material for the drainage layer, and the characteristics of porosity also reflect the high permeability coefficient and porosity. It meets the characteristics of the functional fill material which can quickly drain all rainwater and various waters underground. In addition, due to its low specific gravity, it can be applied to a larger area and volume than natural aggregates at the same weight as natural soil materials, and can be applied more effectively than natural soil materials when applied to load-sensitive parts such as rooftops. have.

In particular, coal ash and slag having latent hydraulic properties generate calcium silicate, calcium aluminate and calcium aluminosilicate hydrate by alkali stimulation, and form hydrates around its own material, thereby continuously increasing the bearing capacity of the roadbed. It can help improve performance when used for fill.

Fly ash, bottom ash, or a mixture thereof may also be used as the coal ash used in the artificial landfill material of the present invention. It can be used in combination with the prescribed particle size and particle size distribution ratio according to the particle size standard of the soil area.The waste concrete can be used at the site of dismantling work or embedded in a landfill, but it can be additionally constructed such as washing and separation of particle size like coal ash. You may use the thing mix | blended in predetermined particle size and particle size distribution ratio according to the particle size standard by a fill area. The slag uses raw slag embedded or buried in the landfill, and, like coal ash, may be used in combination with a predetermined particle size and particle size distribution ratio in accordance with the particle size standards for each construction field.

Coal ash was used as the artificial material used for the filling of the present invention, generated from domestic coal-fired power plants, waste concrete used waste concrete generated after demolition work, and slag used from domestic steel companies. The natural soil material for the fill is in conformity with the quality standards of the soil material specified in the construction specifications, and it is used for the materials that are directly used in the construction site, such as the soil collected from quarrying work in Korea and the soil collected from the construction site. The collected one was used.

In addition, both the artificial soil material and the natural soil material used a particle diameter of 100 mm or less.

The absorption rate of coal ash and waste concrete as the soil material for construction and artificial soil for landfill is 5.48% coal sand, 8.7% waste concrete, 4.0% slag sand, 1.5% natural sand, 3.0% coal ash, waste concrete gravel 4.0%, slag gravel 3.0%, natural gravel 1.0%.

The content ratio of the industrial by-products (reinforcement) in the construction work artificial landfill material of the present invention is preferably 25% by weight or more, especially when the drainage function is required, the weight ratio of natural soil material: coal ash-containing reinforcement is 25:75 ~ 50 It is most preferable that the content is: 50 and the content of coal is 25% by weight or more, and when it is applied to the base layer during road construction, the weight ratio of natural soil material: waste concrete containing reinforcement is 25: 75-50: 50 and the content of waste concrete is It is most preferable that the fill ratio of 12.5 wt% or more, or the natural soil material: the slag-containing reinforcement is 25: 75-50: 50 and the slag content is 12.5 wt% or more. Most preferably, the content ratio is at least 95% by weight. When the content of industrial by-products, including coal ash, in the construction work artificial landfill material of the present invention is less than 25% by weight, the effect on the sand equivalent, porosity and permeability by the artificial landfill material of the present invention is insignificant, and the content is continuously increased. Sand equivalent, porosity and permeability are improved.

Hereinafter, the present invention will be described in detail with reference to the following examples, but the present invention is not limited thereto.

EXAMPLE

In order to compare the performance of the conventional landfill materials using natural soil materials and the artificial landfill materials of construction works according to the present invention using industrial by-products, natural coal materials are mixed with raw coal material, waste concrete, raw material slag, and the like. For each mixing ratio, the performance changes were examined through tests such as liquid limit, plastic index, modified CBR, permeability coefficient, stability, wear rate, and sand equivalent. Each test was carried out according to the test method specified in KS standard.

Example  1: natural as artificial fill material Soil material Coal ash, Waste concrete  And slag on  About Performance test

An experiment was conducted to see if the industrial by-products used in the fill material of the present invention, coal ash, waste concrete and slag satisfy various property standard values of the fill material.

TABLE 3

division Example 1-1 Example 1-2 Example 1-3 Comparative example Natural soil material (% by weight) - - - 100 Coal ash (wt%) 100 - - - Waste Concrete (wt%) - 100 - - Slag (wt%) - - 100 - Liquid limit KS F 2303 NP ^※ NP NP NP Plasticity index KS F 2303 NP NP NP NP Modified CBR KS F 2320 35 75 57 80 Permeability coefficient (cm / sec) KS F 2322 1.435 × 10 ^-2 1.245 × 10 ^-2 1.194 × 10 ^-2 1.153 × 10 ^-2 stability (%) KS F 2507 19.2 15.2 18.7 12.9 Wear rate (%) KS F 2508 38.7 35.6 37.5 32.1 Sand equivalent (%) KS F 2340 68.5 61.8 59.8 58.4    ※ NP: Non-Plastic

In Table 3, the coal ash shows a higher coefficient of permeability than the natural soil material, because the coal ash produced in the combustion process has a structure containing a much larger amount of pores than the natural soil material. Waste concrete and slag, which have high absorption rate and pore like coal ash, also showed higher permeability coefficient than natural soil material. In addition, all of the fill material satisfies the standard 1.0 × 10 ^-2 cm / sec of the fill material permeability coefficient in the construction specifications.

As for the liquid limit and plasticity index, both natural soil material and artificial landfill material showed good values so that the numerical value was not measured, which satisfied both the liquid material liquid limit and the plasticity index standard of 20 or less in the construction specifications.

In addition, in the modified CBR, which means the target value of the strength of roadbed material in the field, waste concrete showed similar values to natural soil material, while coal and slag showed lower values than natural soil material. Was significantly lower than natural soil material. This is because waste concrete, which has the same performance as natural gravel, that is, natural earth, except waste mortar adhering to the surface, and the cement paste mixed with waste mortar has low sustained hydration during immersion. It is considered to be because it hardens due to the reaction. In case of coal ash, a sample with less glass content with relatively weak strength is used. It is believed to have occurred. However, in all cases, the CBR criterion of modified soil material in the construction specification was over 30.

In the wear rate showing the strength of the material, coal, waste concrete, and slag have a relatively poor value compared to natural soil material. It seems to be because it contains waste mortar which has been affected. These results directly affect the stability results, which can be confirmed from the similarity between the stability and the wear rate. However, in all cases, the construction material specification satisfies the below 40 standard of wear rate and the below 20 standard of stability.

In the sand equivalent representing the ratio of sand to clay, coal ash, waste concrete, slag, etc., which contained relatively little fine powder such as clay, appeared better than natural soil materials. This far exceeds the sand equivalent of 25 or more in the construction specifications.

In other words, coal ash, waste concrete, and slag all appear to meet the soil material property criteria in the construction specifications such as modified CBR and permeability coefficient.

Example  2: natural Soil material  Test for artificial fill material consisting of steel and coal ash

The landfill material of the present invention was prepared by mixing only natural soil material and coal ash, and various changes in physical properties of the landfill material according to the mixing ratio were examined.

TABLE 4

division Example 2-1 Example 2-2 Example 2-3 Example 1-1 Comparative example Natural soil material (% by weight) 75 50 25 0 100 Coal ash (wt%) 25 50 75 100 0 Liquid limit KS F 2303 NP NP NP NP NP Plasticity index KS F 2303 NP NP NP NP NP Modified CBR KS F 2320 76 69 56 35 80 Permeability coefficient (cm / sec) KS F 2322 1.135 × 10 ^-2 2.180 × 10 ^-2 1.876 × 10 ^-2 1.435 × 10 ^-2 1.153 × 10 ^-2 stability (%) KS F 2507 15.8 16.4 17.2 19.2 12.9 Wear rate (%) KS F 2508 35.7 36.1 37.5 38.7 32.1 Sand equivalent (%) KS F 2340 62.0 64.7 66.2 68.5 58.4

In Table 4, the permeation performance of the earthen material of the present invention is improved by mixing coal material having better permeability than natural soil material, and in particular, natural soil material: coal ash mixing ratio (weight ratio) in the range of 25:75 to 50:50. Permeability is greatly improved due to the synergistic effect of the combination of natural earth and coal ash.

Since coal ash with low modified CBR is mixed with natural soil material, the modified CBR decreases with increasing coal ash content, but still meets the fill material specification criteria.

In addition, the sand equivalent also increases than the case of using only natural soil material, and generally shows better performance than natural soil material, and it can be seen that coal ash, which is an industrial by-product, serves as an appropriate reinforcement material for natural soil material.

Example  3: natural Soil material , Coal ash and Waste concrete  For artificial fill material Performance test

The soil material of the present invention was prepared by mixing coal material and waste concrete with natural soil material, and the replacement rate of natural soil material was fixed to 50% by weight, which shows the best permeability coefficient in Example 2, to change in the content of coal ash and waste concrete. Various performances of fill materials were measured.

TABLE 5

division Example 3-1 Example 3-2 Example 3-3 Comparative example Natural soil material (% by weight) 50 50 50 100 Coal ash (wt%) 12.5 25 37.5 0 Waste Concrete (wt%) 37.5 25 12.5 0 Liquid limit KS F 2303 NP NP NP NP Firing limit KS F 2303 NP NP NP NP Modified CBR KS F 2320 80.5 78.9 76.1 80 Permeability coefficient (cm / sec) KS F 2322 1.297 × 10 ^-2 1.347 × 10 ^-2 1.568 × 10 ^-2 1.153 × 10 ^-2 stability (%) KS F 2507 15.7 14.9 14.1 12.9 Wear rate (%) KS F 2508 35.7 34.8 36.8 32.1 Sand equivalent (%) KS F 2340 68.7 67.9 68.9 58.4

As shown in Table 5, the landfill material of the present invention consisting of natural soil material, coal ash and waste concrete can be applied to the base layer at the time of road construction because the modified CBR is close to 80 despite the mixing of coal ash having a low modified CBR. Not only does it appear good enough, but the permeability coefficient and sand equivalent also show excellent performance compared to the case of using only natural soil material, and satisfy the respective property standard values in the specification of the fill material.

That is, for better performance, it is preferable to use coal ash and waste concrete together than when only coal ash is mixed with natural soil materials, and it can be seen that waste concrete plays a role of appropriate reinforcing material for coal ash.

Example  4: natural Soil material , Coal ash and With slag  For artificial fill material Performance test

The landfill material of the present invention was prepared by mixing coal material and slag with natural soil material, and the replacement rate of the natural earth material was fixed at 50% by weight as in Example 3 to improve various performances of the landfill material according to the change in the content of coal material and slag. Measured.

TABLE 6

division Example 4-1 Example 4-2 Example 4-3 Comparative example Natural soil material (% by weight) 50 50 50 100 Coal ash (wt%) 12.5 25 37.5 0 Slag (wt%) 37.5 25 12.5 0 Liquid limit KS F 2303 NP NP NP NP Firing limit KS F 2303 NP NP NP NP Modified CBR KS F 2320 81.2 80 78.5 80 Permeability coefficient (cm / sec) KS F 2322 1.218 × 10 ^-2 1.387 × 10 ^-2 1.497 × 10 ^-2 1.153 × 10 ^-2 stability (%) KS F 2507 15.9 16.1 16.9 12.9 Wear rate (%) KS F 2508 34.4 33.7 32.4 32.1 Sand equivalent (%) KS F 2340 58.7 58.5 58.9 58.4

In Table 6, the landfill material of the present invention consisting of natural soil material, coal ash and slag is mixed with coal ash and slag having significantly lower CBR than natural soil material, but the modified CBR of landfill material is approximate 80. Although the slag with the relatively low permeability coefficient was mixed, the permeability coefficient of the fill material was better than that of the natural soil material, and the sand equivalent was similar to that of the natural soil material. Indicated. In addition, the measurement result of the other items also satisfies the respective property reference values on the specification of the fill material.

In other words, for better performance, it is preferable to use coal ash and slag together than natural ash mixed with coal ash only, and the synergistic effect of the combination of the fill material is remarkable when coal ash and slag are mixed. .

Example  5: natural Soil material Coal ash, Waste concrete  And With slag  For artificial fill material Performance test

From the results of Examples 3 and 4, it can be seen that the waste concrete or slag is a suitable component for reinforcing coal ash as a substitute for natural soil material, and the coal soil, waste concrete, and slag are mixed with natural soil material. Materials were prepared, and various performances of fill materials were measured according to the change of the content of coal ash, waste concrete and slag.

TABLE 7

division Example 5-1 Example 5-2 Example 5-3 Example 5-4 Comparative example Natural soil material (% by weight) 25 25 50 50 100 Coal ash (wt%) 25 50 25 12.5 0 Waste Concrete (wt%) 25 12.5 12.5 25 0 Slag (wt%) 25 12.5 12.5 12.5 0 Liquid limit KS F 2303 NP NP NP NP NP Firing limit KS F 2303 NP NP NP NP NP Modified CBR KS F 2320 82.1 76.9 80.3 81.5 80 Permeability coefficient (cm / sec) KS F 2322 1.542 × 10 ^-2 1.687 × 10 ^-2 1.357 × 10 ^-2 1.262 × 10 ^-2 1.153 × 10 ^-2 stability (%) KS F 2507 15.9 16.1 13.9 14.1 12.9 Wear rate (%) KS F 2508 36.8 35.8 34.1 33.8 32.1 Sand equivalent (%) KS F 2340 65.4 66.7 65.1 64.8 58.4

In Table 7, the landfill material of the present invention consisting of natural soil material, coal material, waste concrete, and slag is modified to have a modified CBR of approximately 80 even though the mixture of coal ash and slag has a significantly lower CBR than natural soil material. Not only does it appear good enough to be applied to the base layer during construction, but the permeability coefficient and sand equivalent also show excellent performances compared to the case of using only natural soil material, and satisfy each property standard value in the specification of the fill material. In particular, in the case of Examples 5-1 and 5-2, the improvement of the permeability coefficient can also be confirmed in comparison with the improvement of the modified CBR as described above and the respective components of the fill material.

In view of the results of the above embodiment, natural soil material: coal material containing a coal ash reinforcement is 25:75 ~ 50:50 weight ratio of 25% by weight or more of coal material is efficient in terms of improving drainage function, natural soil Material: Filling material containing 25:75 ~ 50:50 of waste concrete reinforcement and 12.5 wt% or more of waste concrete, or natural earth material: 25:75 ~ 50:50 weight ratio of reinforcing material containing slag It can be seen that the fill material having a content of 12.5 wt% or more is effective in terms of improvement of the modified CBR.

According to the present invention, a natural soil material is mixed with at least one reinforcing material selected from the group consisting of coal ash, waste concrete and slag, and the artificial landfill material for construction workers has a liquid limit, plasticity index, Equal or superior effect can be obtained in modified CBR, permeability coefficient, stability, wear rate, and sand equivalent. In particular, the water permeation performance is improved compared to conventional landfill materials using only natural soil materials, so that the drainage function can be effectively applied as an important soil material in construction work. By replacing with coal ash, waste concrete or slag generated as an industrial by-product can be obtained the effect of waste recycling, natural environment conservation and environmental pollution prevention.

Claims (6)

In the artificial landfill material for construction works comprising (i) natural soil material, and (ii) reinforcement consisting of coal ash and slag, the content ratio of the coal ash is 25% by weight or more, the content ratio of the slag is 12.5% by weight or more Artificial fill material for construction workers, characterized in that. The method of claim 1, Wherein (ii) the reinforcing material further comprises waste concrete, the content of the content of the waste concrete artificial fill material for construction works, characterized in that more than 12.5% by weight. The method according to claim 1 or 2, The particle size of the (i) natural earth material and (ii) reinforcement material is artificial fill material for construction works, characterized in that less than 100mm. delete delete delete