Multi-solid-waste roadbed filling material as well as preparation method and application thereof

Abstract

The invention discloses a multi-solid-waste subgrade filling material and a preparation method and application thereof.The multi-solid-waste subgrade filling material is prepared by adopting different types of industrial waste superfine slag powder, coal ash, coal gangue, carbide slag and steel slag micropowder as main raw materials, adding sodium hydroxide and sodium silicate in a proper proportion as active agents playing an excitation role, and conducting stirring and mixing technological treatment to obtain the multi-solid-waste subgrade filling material. And the multi-solid-waste roadbed filling material disclosed by the invention is obtained through chemical reaction under the condition of normal temperature. The solid waste-based filling material is applied to a roadbed with relatively small bearing capacity and relatively large settlement deformation by utilizing a roadbed treatment technology, so that the aims of increasing the bearing capacity of the roadbed and reducing the settlement deformation are fulfilled.

Description

Technical Field

[0001] The invention relates to the technical field of building materials of industrial solid waste compositions, and in particular to a multi-solid waste roadbed filling material and a preparation method and application thereof. Background Art

[0002] Research on resource utilization of different types of industrial solid waste is carried out, and new solid waste-based roadbed filling materials are developed using a variety of industrial solid waste materials (such as slag, fly ash, coal gangue, carbide slag, steel slag, etc.). While reducing the stockpile of industrial solid waste, it effectively alleviates the greenhouse effect and reduces project costs. It can also improve problems such as large shrinkage and poor water stability of cement-lime stabilized soil.

[0003] Steel slag is a by-product of the industrial steelmaking process, and the amount of steel slag discharged accounts for 15% to 20% of the total steel production. Large quantities of steel slag discharged and stored in open space not only occupy land resources, but also cause serious pollution to the surrounding water, soil and air environment. Therefore, the effective utilization of steel slag resources is an urgent requirement for achieving sustainable development of the steel industry.

[0004] Blast furnace slag is a smelting byproduct formed by complex chemical reactions and heat exchange when the furnace temperature is 1300-1500 degrees during pig iron smelting. Blast furnace slag is formed into spongy granulated slag (also called slag powder GGBS) through water quenching.

[0005] Carbide slag is a byproduct of the production of polyvinyl chloride (PVC). Every ton of PVC produced will produce 1.5 to 1.9 tons of carbide slag. The main component of carbide slag is calcium hydroxide. Its slag liquid is strongly alkaline and contains a small amount of inorganic and organic impurities. According to GB 5085-2007 "Hazardous Waste Identification Standard", it belongs to Class II general industrial solid waste. The reserves of carbide slag are huge. At present, the stockpile of carbide slag in China has reached more than 10 million tons.

[0006] Gangue is a kind of black-gray industrial waste slag composed of multiple rocks with low carbon content but harder than coal. It is produced during the mining and processing of coal. According to statistics, with the continuous mining of coal in my country, the cumulative stockpile of gangue has exceeded 5 billion tons, of which the stockpile of gangue in Shanxi accounts for about one-third of the national stockpile. In recent years, my country has invested a lot of manpower and material resources in the research on the utilization of gangue, and has made great progress, but the comprehensive utilization efficiency of gangue is still very low, and the unused gangue has caused serious impact on the environment. Summary of the invention

[0007] In order to solve the deficiencies of the above technical solutions, the object of the present invention is to provide a multi-solid waste roadbed filling material and a preparation method and application thereof.

[0008] The purpose of the present invention is achieved through the following technical solutions.

[0009] A multi-solid waste roadbed filling material comprises industrial waste and an activator, wherein the industrial waste is slag powder, fly ash, coal gangue, carbide slag and steel slag powder, wherein, by mass, the ratio of the slag powder, fly ash, coal gangue, carbide slag and steel slag powder is (20-35): (15-30): (17-35): (10-15): (8-15).

[0010] In the above technical solution, the mass of the active agent accounts for 2% to 8% of the mass of the industrial waste. Preferably, the mass of the active agent accounts for 2%, 4%, 6% or 8% of the mass of the industrial waste.

[0011] In the above technical solution, the active agents are sodium hydroxide and sodium silicate.

[0012] In the above technical solution, when the mass of the active agent accounts for 2% of the mass of the industrial waste, the unconfined compressive strength is 1.89MPa to 2.27MPa;

[0013] When the mass of the active agent accounts for 4% of the mass of the industrial waste, the unconfined compressive strength is 2.53MPa to 3.08MPa;

[0014] When the mass of the active agent accounts for 6% of the mass of the industrial waste, the unconfined compressive strength is 3.58MPa to 4.20MPa;

[0015] When the mass of the active agent accounts for 8% of the mass of the industrial waste, the unconfined compressive strength is 3.81 MPa to 4.74 MPa.

[0016] Another aspect of the present invention also includes a method for preparing the multi-solid waste roadbed filling material, the steps of which are as follows: slag powder, fly ash, coal gangue, carbide slag and steel slag powder are mixed evenly, and then an activator is added and mixed evenly.

[0017] Another aspect of the present invention also includes the use of the multi-solid waste roadbed filling material in a highway roadbed.

[0018] The advantages and beneficial effects of the present invention are:

[0019] 1. The multi-solid waste roadbed filling material of the present invention uses different types of industrial waste slag powder, fly ash, coal gangue, carbide slag, steel slag powder as main raw materials, and adds appropriate proportions of sodium hydroxide and sodium silicate as activating agents to solve the problem that the CBR value of existing roadbed filling materials used to characterize the stability of road engineering soil is generally unqualified;

[0020] 2. The multi-solid waste roadbed filling material of the present invention adopts different types of industrial waste, slag powder, fly ash, coal gangue, carbide slag and steel slag powder, which not only overcomes the defect of industrial waste seriously polluting the environment and makes effective use of it, but also promotes the solution to the problem of alkali slag accumulation, and has important social benefits.

[0021] 3. The multi-solid waste roadbed filling material of the present invention has abundant raw materials for preparation, simple production process, low price, energy saving, and qualified engineering indicators. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is further described below in conjunction with specific embodiments.

[0023] Example 1

[0024] A method for preparing a multi-solid waste roadbed filling material comprises the following steps: uniformly mixing industrial waste materials of 35% slag powder, 30% fly ash, 17% coal gangue, 10% carbide slag and 8% steel slag powder according to mass percentage, adding a mixture of sodium hydroxide and sodium silicate (sodium hydroxide and sodium silicate each account for 1%) accounting for 2% of the total mass of the industrial waste as an activator, and then uniformly stirring to obtain the multi-solid waste roadbed filling material.

[0025] The unconfined compressive strength of the multi-solid waste roadbed filling material obtained in this example was measured, and the results are shown in Table 1:

[0026] Table 1

[0027]

[0028] It can be seen from Table 1 that the multi-solid waste roadbed filling material has high compressive strength, with an unconfined compressive strength of 1.89MPa to 2.27MPa, which can meet the corresponding engineering bearing capacity requirements such as roadbed filling, and the compressive strength at 28 days old is increased compared to the compressive strength at 7 days old.

[0029] Example 2

[0030] A method for preparing a multi-solid waste roadbed filling material comprises the following steps: mixing industrial waste materials of 30% slag powder, 25% fly ash, 23% coal gangue, 12% carbide slag and 10% steel slag powder evenly by mass percentage, adding a mixture of sodium hydroxide and sodium silicate (sodium hydroxide and sodium silicate each account for 2%) accounting for 4% of the total mass of the industrial waste as an activator, and then stirring evenly to obtain the multi-solid waste roadbed filling material.

[0031] The unconfined compressive strength of the multi-solid waste roadbed filling material obtained in this example was measured, and the results are shown in Table 2:

[0032] Table 2

[0033]

[0034] It can be seen from Table 2 that the multi-solid waste roadbed filling material has high compressive strength, with an unconfined compressive strength of 2.53MPa to 3.08MPa, which can meet the corresponding engineering bearing capacity requirements such as roadbed filling, and the compressive strength at 28 days old is increased compared to the compressive strength at 7 days old.

[0035] Example 3

[0036] A method for preparing a multi-solid waste roadbed filling material comprises the following steps: mixing industrial waste materials of 25% slag powder, 20% fly ash, 29% coal gangue, 14% carbide slag and 12% steel slag powder evenly by mass percentage, adding a mixture of sodium hydroxide and sodium silicate (sodium hydroxide and sodium silicate each account for 3%) accounting for 6% of the total mass of the industrial waste as an activator, and then stirring evenly to obtain the multi-solid waste roadbed filling material.

[0037] The unconfined compressive strength of the multi-solid waste roadbed filling material obtained in this example was measured, and the results are shown in Table 3:

[0038] Table 3

[0039]

[0040] It can be seen from Table 3 that the multi-solid waste roadbed filling material has high compressive strength, with an unconfined compressive strength of 3.58MPa to 4.20MPa, which can meet the corresponding engineering bearing capacity requirements such as roadbed filling, and the compressive strength at 28 days old is increased compared to the compressive strength at 7 days old.

[0041] Example 4

[0042] A method for preparing a multi-solid waste roadbed filling material comprises the following steps: mixing industrial waste materials of 20% slag powder, 15% fly ash, 35% coal gangue, 15% carbide slag and 15% steel slag powder evenly by mass percentage, adding a mixture of sodium hydroxide and sodium silicate (sodium hydroxide and sodium silicate each account for 4%) accounting for 8% of the total mass of the industrial waste as an activator, and then stirring evenly to obtain the multi-solid waste roadbed filling material.

[0043] The unconfined compressive strength of the multi-solid waste roadbed filling material obtained in this example was measured, and the results are shown in Table 4:

[0044] Table 4

[0045]

[0046] It can be seen from Table 4 that the multi-solid waste roadbed filling material has high compressive strength, with an unconfined compressive strength of 3.81MPa~4.74MPa, which can meet the corresponding engineering bearing capacity requirements such as roadbed filling, and the compressive strength at 28 days old is increased compared with the compressive strength at 7 days old.

[0047] The present invention is described above by way of example. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or other equivalent replacement that can be made by those skilled in the art without inventive effort falls within the protection scope of the present invention.

Claims

1. A multi-solid waste roadbed filling material, characterized in that: The invention comprises industrial waste and an active agent, wherein the industrial waste is slag powder, fly ash, coal gangue, carbide slag and steel slag powder, wherein, by weight, the ratio of the slag powder, fly ash, coal gangue, carbide slag and steel slag powder is (20-35): (15-30): (17-35): (10-15): (8-15).

2. The multi-solid waste roadbed filling material according to claim 1, characterized in that: The mass of the active agent accounts for 2% to 8% of the mass of the industrial waste.

3. The multi-solid waste roadbed filling material according to claim 1, characterized in that: The mass of the active agent accounts for 2%, 4%, 6% or 8% of the mass of the industrial waste.

4. The multi-solid waste roadbed filling material according to claim 1, characterized in that: The active agents are sodium hydroxide and sodium silicate.

5. The multi-solid waste roadbed filling material according to claim 1, characterized in that: When the mass of the active agent accounts for 2% of the mass of the industrial waste, the unconfined compressive strength is 1.89MPa to 2.27MPa; When the mass of the active agent accounts for 4% of the mass of the industrial waste, the unconfined compressive strength is 2.53MPa to 3.08MPa; When the mass of the active agent accounts for 6% of the mass of the industrial waste, the unconfined compressive strength is 3.58MPa to 4.20MPa; When the mass of the active agent accounts for 8% of the mass of the industrial waste, the unconfined compressive strength is 3.81 MPa to 4.74 MPa.

6. The method for preparing a roadbed filling material made of multiple solid wastes according to any one of claims 1 to 5, characterized in that: Mix slag powder, fly ash, coal gangue, carbide slag and steel slag powder evenly, then add the activator and mix evenly.

7. Use of the multi-solid waste roadbed filling material as claimed in any one of claims 1 to 5 in highway roadbed.

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