Composite roadbed material, raw material proportioning method of roadbed material and roadbed preparation method

Abstract

The invention belongs to the technical field of road construction, and discloses a composite roadbed material, a raw material proportioning method of the roadbed material and a roadbed preparation method, the composite roadbed material comprises the following raw materials by mass: 70-80 parts of muck; 20 to 30 parts of recycled aggregate; and 4-12 parts of a curing agent. The residue soil particles have certain hardness and pores and can contain the recycled aggregate and fix building solid waste broken objects, the curing agent can react with the residue soil and enhance the stability of the residue soil, and gypsum, fly ash, mineral powder and an exciting agent in the curing agent component can adjust the material performance and delay the cement setting time. Cement and recycled aggregate are mixed, so that cement fully enters gaps of muck when being mixed with the recycled aggregate, the soil structure is denser, the porosity is reduced, the compactness and strength of a soil body are improved, the composite stabilized soil contains porous substances, pores are filled with air, air is extruded through rolling compaction, the compaction degree is increased, virtual laying is avoided, and the overall stability is enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of road construction, and in particular relates to a composite roadbed material, a raw material proportioning method of the roadbed material, and a roadbed preparation method. Background Art

[0002] With the rapid development of modern society and the acceleration of urbanization, resource consumption is increasing, resulting in a large amount of solid waste. According to statistics, the solid waste generated by my country's industry each year has exceeded 3 billion tons and is continuing to grow. According to the current growth trend, the amount of solid waste generated will likely continue to rise in the next few years, bringing great pressure to the environment. Among them, the amount of construction waste is the largest, and the resource utilization rate is still at a low level. The large amount of construction waste and the random dumping will cause serious environmental damage.

[0003] Moreover, in some soft soil areas, soft soil foundations are prone to large settlement under the load of buildings due to their low strength and high compressibility. This settlement may cause uneven settlement of buildings, causing them to tilt and crack, seriously affecting the normal use and safety of buildings. If engineering slag and construction solid waste can be recycled and reused, and a certain amount of curing agent can be added for hardening, it can not only be used as a resource, turning waste into treasure, reducing the cost of on-site disposal and transportation of slag, but also effectively solve the problem of soft soil foundation. At present, there have been many studies on this type of composite roadbed, but there are few studies on the recycling of solid waste materials. Most research methods are not green and environmentally friendly, and have a certain impact on the ecological environment.

[0004] Therefore, there is an urgent need to design a composite roadbed material, a raw material ratio method for roadbed materials, and a roadbed preparation method, which can not only make large-scale use of the construction solid waste that needs to be disposed of, but also make the use of green ecological circular composite roadbed as a road subbase design acceptance index close to the use of water-stabilizing materials, and at the same time avoid uneven settlement of the road surface and road collapse when used in soft soil areas. Summary of the invention

[0005] In order to solve the above problems, the present invention provides a composite roadbed material, a raw material ratio method of the roadbed material and a roadbed preparation method, which solves the problem of uneven settlement in soft soil areas.

[0006] The present invention is implemented by the following scheme: A composite roadbed material comprises the following raw materials in parts by weight:

[0007] 70-80 parts of slag;

[0008] 20-30 parts of recycled aggregate;

[0009] 4-12 parts of curing agent;

[0010] The slag includes one or more of crushed stone soil, sandy soil or fine-grained soil, and the recycled aggregate includes one or more of crushed construction solid waste, crushed stone or steel slag.

[0011] A further improvement of the composite roadbed material of the present invention is that the curing agent comprises cement, gypsum, fly ash, mineral powder and an activator.

[0012] A further improvement of the composite roadbed material of the present invention is that the ratio of cement, gypsum, fly ash, mineral powder and activator in the curing agent is 6:4:4:3:3 (kg / m).

[0013] A further improvement of the composite roadbed material of the present invention is that the particle size of the recycled aggregate is 5 mm to 25 mm.

[0014] A method for proportioning raw materials of roadbed materials comprises the following steps:

[0015] Providing raw material slag, recycled aggregate and curing agent, wherein the slag includes one or more of crushed stone soil, sandy soil or fine-grained soil, and the recycled aggregate includes one or more of crushed construction solid waste, crushed stone or steel slag;

[0016] The moisture content of the slag is tested, and the raw materials are proportioned according to the moisture content, and the slag is 70-80 parts, the recycled aggregate is 20-30 parts, and the curing agent is 4-12 parts.

[0017] A further improvement of the method for proportioning raw materials of roadbed materials of the present invention is that the step of proportioning the raw materials according to the moisture content of the detected slag comprises:

[0018] When the moisture content of the tested slag is ≤25%, the slag is 80 parts, the recycled aggregate is 20 parts and the curing agent is 4-7 parts;

[0019] When the moisture content of the tested slag is >25% and <32%, the slag is 75 parts, the recycled aggregate is 25 parts and the curing agent is 6-10 parts;

[0020] When the moisture content of the detected slag is ≥32%, the slag is 70 parts, the recycled aggregate is 30 parts and the curing agent is 7-12 parts.

[0021] A roadbed preparation method comprises the following steps:

[0022] Providing the composite roadbed material according to claim 1;

[0023] The composite roadbed material is mixed until the mixture is uniformly mixed, and then the mixture is laid, flattened and compacted to obtain a roadbed.

[0024] A further improvement of the roadbed preparation method of the present invention is that the roadbed meets the requirements of 7-day unconfined compressive strength ≥2.5MPa, compaction degree ≥97%, and deflection value ≤130 (0.01mm).

[0025] Compared with the prior art, the present invention has the following beneficial effects:

[0026] The roadbed material of the present invention is based on engineering slag. Based on the principle of local and nearby utilization, it makes extensive use of crushed stone, construction solid waste, steel slag, etc. that need to be disposed of, saving natural resources and social resources and protecting the environment. The slag particles have a certain hardness and porosity, which can accommodate recycled aggregates and realize the fixation of broken construction solid wastes. The curing agent can react with the slag to enhance the stability of the slag. The gypsum, fly ash, mineral powder and activator in the curing agent components can adjust the material properties and delay the cement solidification time, so that the cement can fully enter the slag gap when mixed with the recycled aggregate, making the soil structure more compact and reducing the porosity, thereby improving the density and strength of the soil. The composite stabilized soil contains porous materials, and the pores are filled with air. Rolling and compaction will squeeze out the air, increase the compaction degree, avoid empty paving, and enhance the overall stability. At the same time, by testing the moisture content of the slag used, the mass fraction of each raw material in the roadbed material is proportioned, so that the roadbed formed by the construction of the roadbed material of this application meets the requirements of 7-day unconfined compressive strength ≥2.5MPa, compaction degree ≥97%, bending settlement value ≤130 (0.01mm), etc., to form a composite solidified soil roadbed that can meet the strength requirements of the light traffic base or heavy traffic base of the secondary highway, avoid uneven settlement of the road surface, and solve the problems of road collapse and potholes in soft soil areas. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A schematic diagram of a conventional pavement structure in the prior art is shown.

[0028] In the figure: 1, upper layer; 2, lower layer; 3, sealing layer; 4, base layer; 5, subbase layer. DETAILED DESCRIPTION

[0029] In order to solve the problem of uneven settlement in soft soil areas, the present invention provides a composite roadbed material, a method for mixing raw materials of the roadbed material, and a method for preparing the roadbed. The composite roadbed material, the method for mixing raw materials of the roadbed material, and the method for preparing the roadbed are further described below with specific embodiments and accompanying drawings.

[0030] Example 1

[0031] The present embodiment provides a composite roadbed material, comprising the following raw materials: slag, recycled aggregate and curing agent; wherein the curing agent comprises cement, gypsum, fly ash, mineral powder and activator, and the ratio of cement, gypsum, fly ash, mineral powder and activator in the curing agent is 6:4:4:3:3 (kg / m3); the slag is crushed stone soil, the recycled aggregate is crushed solid waste of construction, and the particle size distribution of the crushed solid waste of construction is 5 mm;

[0032] The raw material proportioning method of the roadbed material comprises the following steps:

[0033] Providing raw material slag, recycled aggregate and curing agent, wherein the slag includes one or more of crushed stone soil, sandy soil or fine-grained soil, and the recycled aggregate includes one or more of crushed construction solid waste, crushed stone or steel slag;

[0034] The moisture content of the slag is detected, and the raw materials are proportioned according to the moisture content, and the slag is 70-80 parts, the recycled aggregate is 20-30 parts, and the curing agent is 4-12 parts; wherein the step of proportioning the raw materials according to the moisture content of the detected slag includes:

[0035] When the moisture content of the tested slag is ≤25%, the slag is 80 parts, the recycled aggregate is 20 parts and the curing agent is 4-7 parts;

[0036] When the moisture content of the tested slag is >25% and <32%, the slag is 75 parts, the recycled aggregate is 25 parts and the curing agent is 6-10 parts;

[0037] When the moisture content of the detected slag is ≥32%, the slag is 70 parts, the recycled aggregate is 30 parts and the curing agent is 7-12 parts.

[0038] The mass proportions of each raw material are: 75 parts of crushed stone soil, 25 parts of crushed construction solid waste and 8 parts of curing agent.

[0039] The construction method of the roadbed comprises the following steps:

[0040] Providing the composite roadbed material described above;

[0041] The raw materials in the composite roadbed material are mixed until the mixture is evenly mixed, turned over and has a uniform color, and then the mixture is laid, flattened and compacted to obtain a roadbed. The obtained roadbed meets the requirements of 7-day unconfined compressive strength ≥2.5MPa, compaction degree ≥97%, and deflection value ≤130 (0.01mm).

[0042] Example 2

[0043] The present embodiment provides a composite roadbed material, which is consistent with the embodiment 1; the present embodiment provides a raw material proportioning method for roadbed materials, which is different from the embodiment 1 in that the mass proportions of each raw material obtained by proportioning are: 75 parts of crushed stone soil, 25 parts of crushed construction solid waste and 10 parts of curing agent; the present embodiment provides a roadbed construction method which is consistent with the embodiment 1.

[0044] Example 3

[0045] This embodiment provides a composite roadbed material. Compared with Example 1, the difference is that the slag is sandy soil, and the particle size distribution of the screened material of the crushed construction solid waste is 10 mm; this embodiment provides a raw material proportioning method for roadbed materials, which is consistent with Example 1; this embodiment provides a roadbed construction method, which is consistent with Example 1.

[0046] Example 4

[0047] The present embodiment provides a composite roadbed material, which is consistent with the embodiment 1; the present embodiment provides a raw material ratio method for roadbed materials, which is different from the embodiment 1 in that the mass proportions of each raw material obtained by the ratio are: 70 parts of crushed stone soil, 30 parts of crushed construction solid waste and 10 parts of curing agent; the present embodiment provides a roadbed construction method, which is consistent with the embodiment 1.

[0048] Comparative Example 1

[0049] This embodiment provides an existing conventional road surface, whose structure includes a surface layer, a sealing layer, a base layer and a subbase layer arranged in sequence from top to bottom, wherein the surface layer includes an upper layer and a lower layer, see Figure 1 As shown, the upper layer 1 adopts 4 cm fine-grained asphalt concrete AC-13C (SBS modified asphalt), the lower layer 2 adopts 6 cm medium-grained asphalt concrete AC-20C (SBS modified asphalt), the sealing layer 3 adopts 0.6 cm emulsified asphalt slurry sealing layer PC-2, the base layer 4 adopts 15 cm cement stabilized gravel (3.5 MPa) + 15 cm cement stabilized gravel (3.5 MPa), and the subbase layer 5 is 20 cm graded crushed stone.

[0050] Example 5

[0051] This embodiment provides a road surface, and its structure is the same as that of comparative example 1, except that the base layer 4 is completely replaced by the roadbed obtained by construction in embodiment 1, and the thickness is 30 cm.

[0052] Deflection detection was performed on multiple lanes of multiple pile numbers on the road surface formed by the roadbed constructed by Examples 1-4, and the detection results are shown in Table 1;

[0053] Table 1:

[0054]

[0055] It can be seen from Table 1 that the average value of roadbed deflection is 95 (0.01mm), the maximum value is 110 (0.01mm), the minimum value is 81 (0.01mm), and the value of each test is more than 130 (0.01mm), which meets the requirements for deflection value of composite solidified soil roadbed with light traffic base or heavy traffic subbase of secondary highway.

[0056] Furthermore, the deflection value, 7d unconfined compressive strength and compaction degree of the conventional roadbed in Reference Document 1 and the composite roadbed in Example 5 were tested, and the test results are shown in Table 2;

[0057] Table 2:

[0058]

[0059] It can be seen from Table 2 that the pavement deflection value, 7d unconfined compressive strength and compaction degree of the conventional roadbed in Comparative Example 1 do not meet the standards. When the roadbed in Example 5 of the present application replaces the roadbed in Comparative Example 1 (cement stabilized gravel layer), the pavement deflection value, 7d unconfined compressive strength and compaction degree all meet the standards.

[0060] From the above tests, it can be known that the composite roadbed of the present invention has a 7d unconfined compressive strength of ≥2.5MPa, a compaction degree of ≥97%, and a deflection value of ≤130 (0.01mm), forming a composite solidified soil roadbed that can meet the strength requirements of the light traffic base or heavy traffic subbase of a secondary highway, avoiding uneven settlement of the road surface, and solving the problems of road collapse and potholes in soft soil areas.

[0061] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0062] The present invention is described in detail above in conjunction with the embodiments of the accompanying drawings. A person skilled in the art can make various variations of the present invention according to the above description. Therefore, certain details in the embodiments should not constitute a limitation of the present invention, and the scope of protection of the present invention shall be defined by the scope of the attached claims.

Claims

1. A composite roadbed material, characterized in that: Including the following raw materials by mass: 70-80 parts of slag; 20-30 parts of recycled aggregate; 4-12 parts of curing agent; The slag includes one or more of crushed stone soil, sandy soil or fine-grained soil, and the recycled aggregate includes one or more of crushed construction solid waste, crushed stone or steel slag.

2. The composite roadbed material according to claim 1, characterized in that: The curing agent includes cement, gypsum, fly ash, mineral powder and activator.

3. The composite roadbed material according to claim 2, characterized in that: The proportion of cement, gypsum, fly ash, mineral powder and activator in the curing agent is 6:4:4:3:3 (kg / m).

4. The composite roadbed material according to any one of claims 1 to 3, characterized in that: The particle size distribution of the recycled aggregate is 5 mm to 25 mm.

5. A method for mixing raw materials of roadbed materials, characterized in that: The steps include: Providing raw material slag, recycled aggregate and curing agent, wherein the slag includes one or more of crushed stone soil, sandy soil or fine-grained soil, and the recycled aggregate includes one or more of crushed construction solid waste, crushed stone or steel slag; The moisture content of the slag is tested, and the raw materials are proportioned according to the moisture content, and the slag is 70-80 parts, the recycled aggregate is 20-30 parts, and the curing agent is 4-12 parts.

6. The method for mixing raw materials of roadbed materials according to claim 5, characterized in that: The step of proportioning the raw materials according to the moisture content of the detected slag comprises: When the moisture content of the tested slag is ≤25%, the slag is 80 parts, the recycled aggregate is 20 parts and the curing agent is 4-7 parts; When the moisture content of the tested slag is >25% and <32%, the slag is 75 parts, the recycled aggregate is 25 parts and the curing agent is 6-10 parts; When the moisture content of the detected slag is ≥32%, the slag is 70 parts, the recycled aggregate is 30 parts and the curing agent is 7-12 parts.

7. A roadbed preparation method, characterized in that: The steps include: Providing the composite roadbed material according to claim 1; The composite roadbed material is mixed until the mixture is uniformly mixed, and then the mixture is laid, flattened and compacted to obtain a roadbed.

8. The roadbed preparation method according to claim 7, characterized in that: The roadbed meets the requirements of 7-day unconfined compressive strength ≥2.5MPa, compaction degree ≥97%, and deflection value ≤130 (0.01mm).

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