Slope protection material based on building beta gypsum as well as preparation method and construction method of slope protection material

Abstract

The invention relates to the technical field of gypsum, and discloses a slope protection material based on building beta gypsum as well as a preparation method and a construction method thereof, the slope protection material comprises 40-55 parts of building beta gypsum, 8-15 parts of phosphogypsum, 2-5 parts of a curing agent, 10-20 parts of fly ash and 40-60 parts of water; the curing agent comprises calcium hydroxide, potassium carbonate, acrylic resin and calcium carbonate. After the slope protection material provided by the invention is cured, the leachate of the slope protection material reaches the first-grade discharge water standard through a vibroflotation water method. The innovation ensures the environmental protection property of the material in the application process, solves the problem of low water stability of the traditional beta gypsum, increases the water softening coefficient of the building beta gypsum to 0.7, solves the influence on the environment in the treatment process, and meets the requirements of green construction and sustainable development.

Description

Technical Field

[0001] The invention relates to the technical field of gypsum, and in particular to a slope protection material based on building beta gypsum, a preparation method thereof, and a construction method thereof. Background Art

[0002] Phosphogypsum is a large amount of solid byproduct produced during the production of wet phosphoric acid in the phosphorus chemical industry. According to the current production process, about 5 tons of phosphogypsum will be discharged for every ton of phosphoric acid produced. However, the traditional method of treating phosphogypsum is mainly based on stockpiling, and the comprehensive utilization ratio is low. This not only occupies a large amount of land resources, but also poses a potential threat to the ecological environment.

[0004] Currently, the main uses of phosphogypsum are cement retarders and building β-gypsum products. However, in practical applications, there are problems such as (1) the residual soluble phosphorus and fluorine in phosphogypsum have high solubility and mobility, and are easy to flow with water, affecting the environmental safety and long-term stability of the material, and it is urgent to stabilize it through effective solidification technology. (2) The fluidity and operability of traditional phosphogypsum-based materials during the construction process are poor, and it is difficult to meet the construction requirements of large-scale engineering applications. At the same time, its strength and durability after consolidation also need to be improved. (3) The construction technology of phosphogypsum-based materials has not yet fully adapted to the actual needs of current projects. The traditional compaction construction method is complex and inefficient, and it is difficult to meet the requirements of rapid and efficient engineering construction. Summary of the invention

[0005] Technical problems solved by the present invention:

[0006] It is used to solve the problems that harmful substances in existing phosphogypsum are difficult to solidify, the mechanical properties of the prepared construction materials are insufficient, and the adaptability of the construction methods is insufficient.

[0007] The technical solution adopted by the present invention is:

[0008] In view of the above technical problems, the object of the present invention is to provide a slope protection material based on building beta gypsum, a preparation method thereof, and a construction method thereof.

[0009] Based on this, the specific implementation plan is:

[0010] First, the present invention provides a slope protection material based on building beta gypsum. The raw material components, measured by weight, include 40 to 55 parts of building beta gypsum, 8 to 15 parts of phosphogypsum, 2 to 5 parts of curing agent, 10 to 20 parts of fly ash, and 40 to 60 parts of water; the curing agent includes calcium hydroxide, potassium carbonate, acrylic resin, and calcium carbonate.

[0011] According to some preferred embodiments, the ratio of the components of the solidified raw materials is 4-5:0.4-0.5:0.08-0.11:0.1-0.2.

[0012] Second, the present invention provides a method for preparing the aforementioned slope protection material based on building beta gypsum, comprising the following steps:

[0013] (1) blending a mixture of building β-gypsum, phosphogypsum and water to obtain a first slurry;

[0014] (2) Add a curing agent and fly ash to the first slurry for blending to obtain a second slurry.

[0015] According to some preferred embodiments, the blending process is: 300-500 r / min, 15-60 s.

[0016] Third, the present invention provides a construction method of a slope protection material, comprising the following steps:

[0017] Spray the second slurry directly onto the slope surface with a spraying thickness of 5 to 10 cm and a construction speed of 2 to 3 m. 2 / min; After spraying, the slope protection surface is preliminarily arranged to ensure the slope is flat. If the slope is not evenly covered, local re-spraying is performed; after spraying, natural curing is carried out. The curing time is 7 days.

[0018] The technical mechanism and beneficial effects adopted by the present invention are as follows:

[0019] (1) The slope protection material provided by the present invention adopts a compounded curing agent to affect the nucleation and growth process of crystals in the early stage of hydration of building β-gypsum, thereby making the generated crystals more regular and flat, reducing the proportion of crystals with needle-shaped or other unfavorable shapes, and improving the overall quality of the material.

[0020] (2) The slope protection material provided by the present invention reacts with the soluble phosphorus and fluorine in the phosphogypsum by adding a curing agent to generate insoluble calcium salts and ettringite crystals. The curing agent also generates calcium hydroxide through a hydration reaction, which stimulates the gelling properties of building β-gypsum and phosphogypsum, wherein CaSO 4 ·2H 2 O forms Ca(OH) in hydration 2 Under excitation, it reacts with calcium aluminate, a hydration product of the curing agent, to form ettringite, which further enhances the strength and stability of the material.

[0021] (4) The slope protection material provided by the present invention can convert harmful components therein into harmless stable materials, and can also be wrapped by resin.

[0022] (5) The slope protection material provided by the present invention, by adding fly ash, can form a hydration product with high strength with calcium ions in gypsum, thereby improving the overall strength of the slope protection material, while also reducing shrinkage cracks caused by drying, and further improving the volume stability of the material. In addition, it can also improve the workability and plasticity during spraying, making construction more convenient.

[0023] (6) The slope protection material provided by the present invention has the advantages of high strength, durability and water stability. It not only effectively utilizes the industrial by-product of phosphogypsum, but also improves the comprehensive performance of the material and solves the weaknesses of traditional materials in slope reinforcement.

[0024] (7) The present invention adopts wet spraying as a construction process, avoiding the complexity of the traditional compaction process. During the construction process, the wet spraying equipment is used to directly spray the material onto the slope protection surface, which not only reduces the construction process, but also improves the construction efficiency and reduces the labor and time costs. In addition, the wet spraying method can ensure uniform coverage of the material and improve the construction quality.

[0025] (8) After the slope protection material provided by the present invention is solidified, its leachate reaches the first-class discharge water standard through the vibratory water method. This innovation ensures the environmental friendliness of the material during application, solves the possible impact of traditional phosphogypsum treatment methods on the environment, and meets the requirements of green construction and sustainable development.

[0026] (9) The slope protection material provided by the present invention is suitable for a variety of engineering environments, including roads, foundation treatment, slope reinforcement and other fields, and has wide applicability and strong market prospects. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the technical scheme in the embodiments of the present invention will be described clearly and completely below. If the specific conditions are not specified in the embodiments, they are carried out according to conventional conditions or conditions recommended by the manufacturer. If the manufacturer of the reagents or instruments used is not specified, they are all conventional products that can be purchased commercially.

[0028] Example 1

[0029] A construction method of a slope protection material based on building beta gypsum comprises the following steps:

[0030] Weigh the raw material components in proportion, including 45 parts of building beta gypsum, 10 parts of phosphogypsum, 12 parts of fly ash and 3 parts of curing agent. The curing agent is composed of calcium hydroxide, potassium carbonate, acrylic resin and calcium carbonate in a ratio of 4:0.4:0.1:0.2.

[0031] A mixture of building β-gypsum, phosphogypsum and water was blended at 500 r / min for 30 seconds to obtain a first slurry; a curing agent and fly ash were added to the first slurry and blended at 500 r / min for 30 seconds to obtain a second slurry.

[0032] The second slurry is sprayed directly onto the slope protection surface through wet spraying equipment. The spraying thickness is controlled at 5-10cm according to the design requirements, and the construction speed is about 2-3m 2 / min. Keep the equipment running evenly during the spraying process to ensure that there are no voids or cracks on the construction surface. After the spraying is completed, the slope protection surface is preliminarily sorted to ensure that the slope is flat, and check whether the material coverage is uniform. If necessary, local re-spraying is performed. After the spraying construction is completed, natural curing treatment is carried out for 7 days.

[0033] Example 2

[0034] The difference between this embodiment and embodiment 1 is that the mass ratios of the slope protection materials are different.

[0035] 50 parts of building beta gypsum, 10 parts of phosphogypsum, 15 parts of fly ash, and 5 parts of curing agent.

[0036] Comparative Example 1

[0037] The difference between this comparative example and Example 1 is that no curing agent is added.

[0038] Test example

[0039] Using Examples 1-2 and Comparative Example 1 as samples, the 3h wet flexural strength and 7d compressive strength were measured. The results are shown in Table 1.

[0040] Table 1

[0041] Measurement indicators Example 1 Example 2 Comparative Example 1 Wet flexural strength MPa 2.5 2.6 1.8 Compressive strength MPa 5.8 5.4 3.6 Water softening coefficient 0.72 0.71 0.52 Water immersion strength MPa 4.2 3.8 1.9

[0042] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A slope protection material based on building beta gypsum, characterized in that: The raw material components are calculated by weight and include 40-55 parts of building beta gypsum, 8-15 parts of phosphogypsum, 2-5 parts of curing agent, 10-20 parts of fly ash and 40-60 parts of water; the curing agent includes calcium hydroxide, potassium carbonate, acrylic resin and calcium carbonate.

2. The slope protection material based on building beta gypsum according to claim 1, characterized in that: The ratio of each component of the solidified raw material is 4-5:0.4-0.5:0.08-0.11:0.1-0.

2.

3. The method for preparing the slope protection material based on building beta gypsum according to any one of claims 1 to 3, characterized in that: The steps include: (1) blending a mixture of building β-gypsum, phosphogypsum and water to obtain a first slurry; (2) Add a curing agent and fly ash to the first slurry for blending to obtain a second slurry.

4. The method for preparing the slope protection material based on building beta gypsum according to claim 4, characterized in that: Blending process: 300-500r / min, 15-60s.

5. A construction method for the slope protection material obtained by the preparation method according to claim 4 or 5, characterized in that: The steps include: The second slurry is sprayed directly onto the slope protection surface by wet spraying equipment; after spraying, the slope protection surface is preliminarily sorted to ensure that the slope surface is flat; after spraying construction is completed, natural curing treatment is carried out.

6. The construction method of the slope protection material according to claim 5, characterized in that: The spraying thickness is 5-10cm and the construction speed is 2-3m 2 / min.

7. The construction method of the slope protection material according to claim 5, characterized in that: If the slope surface is not evenly covered, local spraying should be carried out.

8. The construction method of slope protection material according to claim 5, characterized in that: The maintenance time is 7 days, and the maintenance method is natural maintenance.