A rubber-plastic micro-powder fluidized solid waste light soil and a preparation method thereof
By preparing lightweight solid waste fluidized soil made of rubber and plastic micropowder, the problem of insufficient performance of EPS granular foam concrete after casting and setting was solved, realizing the resource reuse and performance improvement of rubber and plastic micropowder, and meeting the requirements for road construction and filling materials.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- GUANGDONG XINTANG SONG NEW TECHNOLOGY CO LTD
- Filing Date
- 2024-05-06
- Publication Date
- 2026-06-09
Smart Images
Figure CN118307285B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of road construction and filling materials technology, and mainly to a rubber-plastic micropowder fluidized solid waste lightweight soil and its preparation method. Background Technology
[0002] Traditional backfilling projects typically involve compaction using granular materials. However, granular materials have limitations, including large operational margins, high subsequent loss rates, and often insufficient strength to meet requirements, potentially leading to settlement risks. Furthermore, with increasingly stringent environmental regulations, high-quality backfill resources are becoming increasingly scarce, leading more and more backfilling projects to abandon granular materials. New, inexpensive, and readily available alternative backfilling materials have become a new research and development direction for infrastructure projects.
[0003] There is an urgent need to treat and reuse waste plastics or rubber on a large scale.
[0004] Lightweight soil, as a novel filling material, has a wide range of applications and is economical and practical. Currently, its lightweight nature generally comes from the addition of air to form foam. By mixing cementable materials with water and then injecting the foam into the mixture, a fluid, workable lightweight soil is formed. It can be used in both cast-in-place and precast applications. The materials used are relatively inexpensive, significantly reducing material costs compared to traditional stone and gravel, and allowing for the laying of more roads or backfilling within a limited budget. Furthermore, various types of lightweight soil have been proposed to replace the lightweight components according to specific needs. Currently, in the field of building insulation engineering, EPS foam particle concrete has been proposed. This concrete uses EPS foam particles as a lightweight component, allowing for the recycling and reuse of the white plastic in the EPS foam particles. Moreover, the amount used when filling roadbeds with lightweight soil is considerable, effectively reducing pollution. The EPS foam particles used are required to have a 5mm sieve residue of no more than 5%, which is good for the production of thermal insulation pre-components. However, the EPS particle foam concrete has problems with dispersibility and workability when cast in place, which limits its application in road construction filling fields that require large-scale cast-in-place construction. The performance after casting and setting is also difficult to meet the requirements of road filling.
[0005] Therefore, existing technologies still need to be improved and developed. Summary of the Invention
[0006] In view of the shortcomings of the prior art, the purpose of this application is to provide a lightweight solid waste material with rubber and plastic micro powder and its preparation method, which aims to solve the problem that the performance of existing EPS particle foam concrete after casting and setting is difficult to meet the requirements for filling.
[0007] The technical solution of this application is as follows:
[0008] In a first aspect, this application provides a lightweight soil material made from rubber and plastic micropowder fluidized solid waste, comprising the following raw materials:
[0009] (1) Solid materials; solid materials include solid waste binder and rubber and plastic micro powder; the solid waste binder, calculated by weight, includes:
[0010] 40-60 parts solid waste base material, 50-60 parts hydraulic cementitious material, 0.3-3 parts admixture, and 0.03-0.05 parts hydroxyethyl methyl cellulose;
[0011] The volume fraction of the rubber and plastic micro powder in the solid material is 10%-70%;
[0012] (2) Water; the weight ratio of water to solid material is 0.5-0.7:1.
[0013] The rubber-plastic micropowder fluidized solid waste lightweight soil provided in this application utilizes a large amount of solid waste base material, which can address the problem of solid waste disposal. By using rubber-plastic micropowder as a lightweight component in the fluidized solid waste lightweight soil, it can undergo good solidification under the action of hydraulic cementitious materials, and can also effectively solve the problem of recycling rubber or plastic waste. The resulting rubber-plastic micropowder fluidized solid waste lightweight soil also exhibits good compressive strength and fatigue resistance after hardening, demonstrating excellent overall performance. As a lightweight material, it can effectively meet the requirements for road construction and filling.
[0014] Furthermore, the particle size of the hydroxyethyl methyl cellulose is 80-160 μm.
[0015] Furthermore, the rubber and plastic micro powder is one or more of waste foamed PU micro powder, EPS micro powder and rubber micro powder; the volume content of the rubber and plastic micro powder is 20%-70%.
[0016] Furthermore, the particle size of the rubber and plastic micro powder is 0.5-1 mm.
[0017] Furthermore, the rubber-plastic micro powder is a combination of EPS micro powder and rubber micro powder, and the volume ratio of EPS micro powder to rubber micro powder is 1:9.
[0018] Furthermore, the additive is a combination of triethanolamine and sodium sulfate.
[0019] Furthermore, the hydraulic cementitious material is a combination of cement and blast furnace slag powder, wherein the weight ratio of cement to blast furnace slag powder is 1:1-4.
[0020] Furthermore, the solid waste base material is one of the following: fly ash, desulfurization ash, desulfurization gypsum, red mud, alkali slag, ceramic polishing slag, carbide slag, tailings slag, phosphogypsum, and stone sawing mud.
[0021] Furthermore, the specific surface area of the solid waste base material is not less than 200 m². 2 / Kg.
[0022] Secondly, this application also provides a method for preparing lightweight solid waste material made of rubber and plastic micropowder as described in the first aspect, comprising the following steps:
[0023] The rubber and plastic micro powder, hydroxyethyl methyl cellulose and a portion of hydraulic cementitious material are mixed, allowed to stand, and then the additives are added and mixed to obtain a second mixture.
[0024] Then, the solid waste base material and the remaining hydraulic cementitious material are added to the second mixture to obtain the third mixture;
[0025] The third mixture and the water were mixed according to the water-to-solid ratio to obtain a wet rubber-plastic micropowder fluidized solid waste lightweight soil composition;
[0026] The particle size of the hydroxyethyl methyl cellulose is 80-160 μm;
[0027] The mass ratio of the partial hydraulic cementitious material to the remaining hydraulic cementitious material is 1:19;
[0028] The additive is a combination of triethanolamine and sodium sulfate.
[0029] Beneficial effects: The rubber and plastic micro-powder fluidized solid waste lightweight soil provided in this application can address the disposal problems of solid waste base materials and plastic rubber, achieving resource reuse. Furthermore, it exhibits good workability after preparation, allowing for large-scale in-situ casting or filling construction. It possesses excellent compressive strength and fatigue resistance, outperforming ordinary foamed lightweight soil, and effectively meets the construction and usage requirements of roadbeds or filling materials. Attached Figure Description
[0030] Figure 1 This is a graph showing the cumulative displacement and cumulative deformation curves of the compressive fatigue resistance of the rubber-plastic micropowder fluidized solid waste lightweight soil of Example 3 of this application. Detailed Implementation
[0031] This application provides a lightweight solid waste material in the form of rubber and plastic micropowder and its preparation method. To make the objectives, technical solutions, and effects of this application clearer and more explicit, the following provides a more detailed description. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0032] This application provides a lightweight, fluidized solid waste soil made of rubber and plastic micropowder, comprising the following raw materials:
[0033] (1) Solid materials; solid materials include solid waste binders and rubber and plastic powders; solid waste binders, calculated by weight, include:
[0034] 40-60 parts of solid waste base material;
[0035] 50-60 parts of hydraulic cementitious material;
[0036] Additive 0.3-3 parts;
[0037] Hydroxyethyl methylcellulose 0.03-0.05 parts;
[0038] The volumetric content of rubber and plastic micro powder in solid materials is 10%-70%;
[0039] (2) Water; the weight ratio of water to solid material is 0.5-0.7:1.
[0040] The rubber-plastic micropowder fluidized solid waste lightweight soil provided in this application utilizes a large amount of solid waste base material, which can address the problem of solid waste disposal. By using rubber-plastic micropowder as a lightweight component in the fluidized solid waste lightweight soil, it can undergo good solidification under the action of hydraulic cementitious materials, and can also effectively solve the problem of recycling rubber or plastic waste. The resulting rubber-plastic micropowder fluidized solid waste lightweight soil also exhibits good compressive strength and fatigue resistance after hardening, demonstrating excellent overall performance. As a lightweight material, it can effectively meet the requirements for road construction and filling.
[0041] The weight ratio of water to solid material in this application is the water-solid ratio. Maintaining the water-solid ratio at 0.5-0.7:1 helps to maintain the performance of lightweight soil and improve the workability of large-scale cast-in-place construction. It also helps to improve the distribution stability of rubber and plastic powder in the slurry.
[0042] Furthermore, the solid waste base material is one of the following: fly ash, desulfurization ash, desulfurization gypsum, red mud, alkali slag, ceramic polishing slag, aluminum ash, carbide slag, tailings slag, phosphogypsum, and stone sawdust (limestone powder). The solid waste base material selected in this application is industrial solid waste, which can generally be reused depending on local solid waste resources. Different solid waste base materials have different properties, and the corresponding hydraulic cementitious materials and water-to-solid ratio during preparation can be adjusted accordingly. For example, alkali slag contains more active components than other solid waste base materials, and some of its calcium components can also participate in the hydration reaction. When used as a solid waste base material, the amount of hydraulic cementitious material can be appropriately reduced, and the strength prepared using alkali slag as a solid waste base material is relatively higher. Similarly, desulfurization ash has a higher water requirement, so the water-to-solid ratio needs to be appropriately increased when used as a solid waste base material to ensure the hydration reaction proceeds. Furthermore, ceramic polishing slag has higher mechanical strength but also more inert components, so the amount of hydraulic cementitious material can be appropriately increased to ensure the bonding effect and strength.
[0043] Furthermore, the specific surface area of the solid waste substrate is not less than 200 m². 2 / Kg. Solid waste base material, as a major component, significantly impacts the flowability of the rubber-plastic micropowder fluidized solid waste lightweight soil. By using solid waste base material with a large specific surface area to maintain a low particle size, the workability of the rubber-plastic micropowder fluidized solid waste lightweight soil is improved, facilitating casting and exhibiting higher activity. After hardening, it enhances the overall cementing effect of the rubber-plastic micropowder fluidized solid waste lightweight soil. Furthermore, this application's rubber-plastic micropowder fluidized solid waste lightweight soil also incorporates rubber-plastic micropowder. The smaller particle size of the solid waste base material further improves the dispersion of the rubber-plastic micropowder. During water mixing, it also enhances the bonding ability of the solid waste base material and hydraulic cementitious materials to the rubber-plastic micropowder, effectively encapsulating the rubber-plastic micropowder and preventing weak bonding areas from cracking after hardening. This effectively cements and solidifies the rubber-plastic micropowder within the rubber-plastic micropowder fluidized solid waste lightweight soil, facilitating large-scale in-situ casting of the rubber-plastic micropowder fluidized solid waste lightweight soil.
[0044] Furthermore, the hydraulic cementitious material is one or both of cement and mineral powder. The cement is silicate cement or ordinary silicate cement; the mineral powder is blast furnace slag powder. Existing granular materials used for filling generally provide strength through the friction and interlocking forces between particles, making self-stabilization difficult, resulting in mediocre filling effects and high loss rates. In this application, the hydraulic cementitious material is used to bind and consolidate the solid waste base material and rubber-plastic micropowder. Van der Waals forces constrain the components, resulting in a fluid solid waste lightweight soil made of rubber-plastic micropowder that maintains its filling effect and provides strength for a long time after hardening, with higher overall strength. Because this application incorporates a relatively large amount of solid waste base material and lightweight components, the amount of hydraulic cementitious material needs to be maintained at 50-60 parts to ensure the overall binding effect.
[0045] Furthermore, the hydraulic cementitious material is preferably a combination of cement and blast furnace slag powder, with a weight ratio of cement to blast furnace slag powder of 1:1-4. In this application, by using cement and blast furnace slag powder as the base material for the hydration reaction, the selected blast furnace slag powder can undergo a secondary hydration reaction by the hydration products of cement. This results in lower early strength but a faster rate of strength improvement in later stages. Besides reducing the amount of cement used, it also plays an active role in the hydration reaction. However, without adding additional activators, further increasing the amount of blast furnace slag powder cannot fully utilize the activity of the remaining blast furnace slag powder, resulting in a generally limited effect on improving early strength and potentially affecting the overall strength after hardening. Therefore, it is necessary to control the amount of blast furnace slag powder used within a certain range to maintain the strength of the rubber-plastic micro-powder fluidized solid waste lightweight soil and reduce material costs.
[0046] Furthermore, the additive is present in the solid waste binder at a weight ratio of 0.3-3 parts. The solid waste base material of this application has a relatively large content, and by using an appropriate amount of additive, the overall performance of the rubber and plastic micropowder fluidized solid waste lightweight soil can be improved.
[0047] Furthermore, the admixture is a combination of triethanolamine and sodium sulfate. Triethanolamine is a liquid, but the overall dosage of the admixture is relatively small; for ease of water-to-solid ratio calculation, the admixture is also considered a solid material. In this application, the use of triethanolamine can adjust the interfacial properties between the rubber-plastic powder and the cementitious matrix, improving fluidity and workability of the binder. The use of sodium sulfate can accelerate the setting speed, enhance the fixing effect on the rubber-plastic powder in the early setting stage, and improve the strength and durability of the binder after setting, thus improving workability. In actual use, the dosage of the admixture can be determined according to the performance requirements of specific working conditions.
[0048] In this application, the volumetric content of rubber-plastic micropowder in the solid material is 10%-70%. Generally, the higher the content of rubber-plastic micropowder in lightweight soil, the lower the strength of the lightweight soil. In actual working conditions, the volumetric content of rubber-plastic micropowder can be adjusted according to the required performance. In addition, increasing the volumetric content will reduce the fluidity of the resulting liquid solid waste lightweight soil, and since the scale of filling is relatively large, controlling the volumetric content can reduce costs while ensuring the casting performance of the lightweight soil.
[0049] Furthermore, the rubber-plastic micro powder is one or more of waste foamed PU micro powder, EPS micro powder, and rubber micro powder. Foamed PU plastic, EPS granules, and rubber have wide applications and are used in large quantities daily, resulting in significant waste problems. They are readily available and reusable. The rubber-plastic micro powder used also possesses a certain degree of hydrophobicity, which, when mixed in, can improve the overall weather resistance of the fluidized solid waste lightweight soil, thus helping to reduce the loss rate after filling.
[0050] The volumetric content of the rubber and plastic micro powder is 20%-70%. Volumetric content represents the air content in the rubber and plastic micro powder. In this application, if the volumetric content of the rubber and plastic micro powder is too high, it is prone to accumulation or agglomeration, increasing the risk of pore collapse and a greater tendency to float upwards. This can also easily lead to defects during the solidification stage. Conversely, if the volumetric content of the rubber and plastic micro powder is too low, it is difficult to exert its lightweight effect. By controlling the volumetric content of the rubber and plastic micro powder, its lightweight effect in fluidized solid waste lightweight soil can be guaranteed, and the potential adverse effects of lightweight components can be mitigated, achieving recycling and reducing pollution.
[0051] Furthermore, the particle size of the EPS (expanded polystyrene) powder is no greater than 1 mm. Currently, general EPS particle foam concrete is prepared using EPS particles with larger particle sizes. These particles have poor workability, and as lightweight components, they are more prone to floating. They also exhibit poor compatibility and dispersibility in fluidized lightweight soil, easily leading to stratification, segregation, or partial accumulation. Moreover, the hydraulic cementitious materials in fluidized lightweight soil struggle to achieve good bonding with large-particle EPS particles, increasing weaknesses in the hardened lightweight soil and making it difficult to guarantee overall strength after hardening. Therefore, large-particle EPS not only makes large-scale in-situ casting difficult, causing challenges in concrete application, but also makes it difficult to ensure sufficient strength and compressive strength in the hardened lightweight soil. To address this issue, this application controls the use of rubber and plastic micro powder with a particle size of no more than 1 mm, thereby increasing the specific surface area of the rubber and plastic micro powder. This enhances the effect of the cementitious material on the rubber and plastic micro powder, making it easier for the rubber and plastic micro powder to be encapsulated and participate in cementation and solidification. The rubber micro powder is less likely to float, which also helps to improve the dispersion effect in fluid solid waste lightweight soil, reduce weak points, and improve the uniform distribution of the strength of the lightweight soil.
[0052] Preferably, the particle size of the rubber-plastic micro powder is 0.5-1 mm. In this application, after recovering waste foamed PU particles, waste EPS particles, or waste rubber with larger particle sizes, they can be mechanically crushed to the required particle size using a crusher, and then sieved, washed, and dried before being used as rubber-plastic micro powder. Generally speaking, the smaller the particle size of the rubber-plastic micro powder, the better its dispersion in fluidized solid waste lightweight soil, and the higher its strength. However, smaller particle sizes of the rubber-plastic micro powder result in higher costs, and compared to the reduction in strength after incorporation, the increase in strength is negligible. Furthermore, the lightweight soil provided in this application is mainly made from the recycling of existing waste rubber and plastic granules. The rubber and plastic micro powder is mainly obtained through re-crushing rather than active foaming. If the rubber and plastic micro powder is further crushed to a smaller particle size, the volume content of the rubber and plastic granules is not completely matched with the particle size, resulting in greater performance changes. Some uniform and closed cavity structures will be destroyed, leading to a decrease in volume content, especially for waste foamed PU granules and EPS granules. Further crushing to a smaller particle size will reduce the lightweight effect and thermal insulation effect. At larger dosages, the performance of the lightweight soil is more easily affected and difficult to control. Therefore, the particle size of the rubber and plastic micro powder in this application is more preferably 0.5-1mm, which is suitable for actual reuse conditions. This ensures the workability of the resulting fluidized solid waste lightweight soil while maintaining the basic properties of the rubber and plastic micro powder, thus guaranteeing the lightweight effect of the rubber and plastic micro powder in the fluidized solid waste lightweight soil.
[0053] In this application, the provided fluidized solid waste lightweight soil made from rubber and plastic micropowder is easy to prepare and readily available. When used for road construction filling, the preparation is generally based on local solid waste resources and recycled rubber and plastic resources, and the solid waste base material and rubber and plastic raw materials used are usually one of these, making mixing and preparation convenient. Among the rubber and plastic micropowders, rubber micropowder is the preferred choice. Rubber micropowder has a higher solid content than ordinary waste foamed PU micropowder or EPS micropowder, resulting in fluidized solid waste lightweight soil with relatively higher strength and improved toughness, which is beneficial for its application in roadbed filling. Using rubber micropowder as the main lightweight filler is more effective in reducing drying shrinkage deformation compared to using EPS micropowder or waste foamed PU micropowder, reducing shrinkage crack propagation and maintaining the overall strength and compressive fatigue resistance of the fluidized solid waste lightweight soil made from rubber and plastic micropowder. Therefore, using rubber micropowder as the main lightweight component is more effective.
[0054] Furthermore, the rubber-plastic micro-powder is a combination of EPS micro-powder and rubber micro-powder, with a volume ratio of EPS micro-powder to rubber micro-powder of 1:9. The volume content of EPS particles is generally relatively high, especially for commonly used EPS particles with a particle size of 5mm. Their contribution to the strength of the resulting lightweight soil is negligible, and further increasing the admixture ratio will reduce the overall strength of the lightweight soil. However, in this application, the inventors discovered through experiments that when rubber-plastic micro-powder is used primarily as a base, combined with waste foamed PU micro-powder or EPS micro-powder in a certain proportion, the compressive fatigue resistance of the fluidized solid waste lightweight soil is improved, with the combination of rubber micro-powder and EPS micro-powder being particularly superior. The inventors speculate that because the solid waste base material, EPS micro-powder, and rubber micro-powder used in this application have small particle sizes, the properties of small-particle-size micro-powders are more pronounced, and their influence on the strength of the fluidized solid waste lightweight soil is greater. Compared to waste foamed PU micropowder, the volume content difference between EPS micropowder and rubber micropowder is greater. By combining EPS micropowder and rubber micropowder as lightweight components and uniformly distributing them in lightweight soil, the rubber micropowder reduces shrinkage and provides a certain degree of toughness after hardening. Simultaneously, the property differences between EPS particles and rubber micropowder create a certain mechanical transfer transition within the lightweight soil, improving its compressive strength. After combined use, the overall deformation recovery of the fluidized solid waste lightweight soil is also better, thus improving its compressive fatigue resistance. In this combination, further increasing the amount of EPS micropowder has a greater impact on the strength reduction of EPS micropowder, while too small an amount of EPS micropowder makes it difficult to achieve the performance improvement effect. Therefore, the optimal volume ratio of EPS micropowder to rubber micropowder is 1:9. Maintaining this volume ratio helps to preserve the toughness-improving effect of rubber micropowder while improving the compressive fatigue resistance of the rubber-plastic micropowder fluidized solid waste lightweight soil.
[0055] Hydroxyethyl methyl cellulose (HEMC) can be used as an additive to improve the uniformity of solid lightweight soil composed of rubber-plastic micropowder. In this application, the rubber-plastic micropowder used has a higher degree of air isolation, and its properties are significantly different from those of mixed foam or foam-forming bubbles, resulting in a more pronounced upward floating tendency of the rubber-plastic micropowder during the setting process. The added HEMC has a thickening effect, which, after being formulated into a slurry, can improve the binding and encapsulation effect on the rubber-plastic micropowder, effectively suppressing its upward floating tendency. However, too little HEMC will have little effect, while too much will affect the water-to-solid ratio and fluidity of the lightweight soil, and may also lead to increased shrinkage. This application maintains the HEMC dosage at 0.03-0.05 parts to ensure the binding effect of the rubber-plastic micropowder in the lightweight soil and reduce the risk of shrinkage.
[0056] Furthermore, since the rubber-plastic micropowder is a directly incorporated lightweight component, its compatibility with other inorganic binders, as an organic compound, needs to be considered. This is especially true given the use of smaller-sized rubber-plastic micropowder in this application, which increases the specific surface area and makes its hydrophobic effect more pronounced. Since the consolidation of lightweight soil primarily occurs through hydration reactions, the filling effect of the hydration products at the interface between the cement matrix and the rubber-plastic micropowder is difficult to guarantee, resulting in relatively weak bonding at the interface. Increased dosage can easily lead to structural looseness or porosity, affecting the overall strength of the lightweight soil. To address this issue, the compatibility of the rubber-plastic micropowder in lightweight soil can be improved by hydrophilic modification. For example, the rubber-plastic micropowder can be treated with an alkaline solution by immersing it in sodium hydroxide solution to increase its hydrophilicity, thereby improving its compatibility in lightweight soil.
[0057] However, alkaline treatment also has limitations. For example, if the EPS powder is soaked in a high-concentration sodium hydroxide solution for a long time, the hydrophobic effect of the EPS powder is greatly weakened, making it difficult to improve the weather resistance. Moreover, the remaining cavities of the EPS powder are easily damaged, so the effect on improving the overall performance of lightweight soil is not ideal.
[0058] Furthermore, the particle size of hydroxyethyl methyl cellulose is 80-160 μm. To overcome the limitations of existing modification methods, using hydroxyethyl methyl cellulose with a suitable particle size can further improve the compatibility of rubber-plastic micropowder in lightweight soil. In this application, the surface of the crushed rubber-plastic micropowder has a certain microporous, cavitary, or recessed structure, and its size is generally within a certain range. By using hydroxyethyl methyl cellulose with a particle size within a suitable range, it can be adapted to the microporous structure in the rubber-plastic micropowder. The mixed microporous structure more easily adsorbs and traps hydroxyethyl methyl cellulose, resulting in a better fixation effect. Hydroxyethyl methyl cellulose (HMC) also has water-absorbing and water-retaining properties. After adhering to the surface, it provides sites for easy participation in the hydration reaction of the rubber-plastic micropowder. It doesn't need to completely cover the micropowder, so when mixed with other raw materials, the properties of HMC can temporarily weaken the hydrophobic effect of the micropowder, improving its compatibility in lightweight soil. Simultaneously, as the hydration reaction proceeds, hydration products are generated near the micropowder, improving the filling density at the interface and reducing defects. This also helps reduce the deformation of the lightweight soil containing fluidized solid waste. Furthermore, after the HMC-coated rubber-plastic micropowder is evenly distributed in the lightweight soil, the solidification process can improve the continuity of the cementation of hydration products, facilitating the transfer of mechanical energy and improving toughness, thus enhancing the uniformity of internal stress distribution in the lightweight soil under load. Moreover, after complete solidification, the hydrophobic properties of the rubber and plastic micro powder can be maintained, thus preserving its effect on improving the weather resistance of the fluidized solid waste lightweight soil, which is beneficial to improving the crack resistance and impermeability of the lightweight soil.
[0059] The rubber and plastic micropowder fluidized solid waste lightweight soil provided in this application can address the disposal issues of solid waste materials and plastic rubber, achieving resource recycling. Furthermore, it exhibits good workability after preparation, allowing for large-scale in-situ casting or filling construction. It also possesses good compressive strength and fatigue resistance, effectively meeting the construction and usage requirements of roadbeds or filling materials.
[0060] This application also provides a method for preparing the rubber and plastic micropowder fluidized solid waste lightweight soil as described above, which includes the following steps:
[0061] Solid waste base material, hydraulic cementitious material, additives and hydroxyethyl methyl cellulose are mixed to obtain a first mixture;
[0062] The first mixture and water were mixed according to the water-to-solid ratio to obtain a wet rubber-plastic micropowder fluidized solid waste lightweight soil composition.
[0063] In actual working conditions, the wet rubber-plastic micropowder fluidized solid waste lightweight soil composition is spread onto the surface of the substrate and solidified to obtain rubber-plastic micropowder fluidized solid waste lightweight soil.
[0064] In this process, the solid waste base material, hydraulic cementitious material, admixture, and hydroxyethyl methyl cellulose are mixed to obtain a first mixture, which can then be allowed to stand before being mixed with water. In this application, the volume of the rubber-plastic micropowder is significantly affected by temperature. During the mixing process, friction causes a temperature rise, leading to softening and expansion of the micropowder, as well as enlargement of some surface pores. This improves the adhesion of hydroxyethyl methyl cellulose with a suitable particle size. After mixing, the first mixture can be allowed to stand until stable, causing the volume of the rubber-plastic micropowder to shrink. This helps to hold and fix the hydroxyethyl methyl cellulose, improving the bonding effect between the micropowder and hydroxyethyl methyl cellulose, and thus enhancing the cementing performance of the micropowder in lightweight soil.
[0065] Furthermore, the method for preparing the rubber and plastic micropowder fluidized solid waste lightweight soil of this application includes the following steps:
[0066] Rubber and plastic micro powder, hydroxyethyl methyl cellulose and some hydraulic cementitious materials are mixed, allowed to stand, and then additives are added and mixed to obtain a second mixture;
[0067] Then, solid waste base material and residual hydraulic cementitious material are added to the second mixture to obtain the third mixture;
[0068] The third mixture and water were mixed according to the water-to-solid ratio to obtain a wet rubber-plastic micropowder fluidized solid waste lightweight soil composition.
[0069] The hydroxyethyl methyl cellulose has a particle size of 80-160 μm; the mass ratio of part of the hydraulic cementitious material to the remaining hydraulic cementitious material is 1:19; the admixture is a combination of triethanolamine and sodium sulfate.
[0070] In this application, the cement and blast furnace slag powder products and sodium sulfate admixture products in the hydraulic cementitious materials generally have particle size requirements and small particle sizes. By first mixing the rubber-plastic micro-powder with hydroxyethyl methyl cellulose of suitable particle size and a portion of the hydraulic cementitious materials, the bonding effect between the rubber-plastic micro-powder and hydroxyethyl methyl cellulose is improved. Simultaneously, a small portion of the hydraulic cementitious materials is sealed within the cavities of the rubber-plastic micro-powder. After static stabilization, the addition of triethanolamine from the admixture provides a certain degree of fixation. When subsequently mixed with the remaining materials and water, triethanolamine also regulates the interfacial properties of the rubber-plastic micro-powder, improving its compatibility in lightweight soil. During the solidification process, the hydroxyethyl methyl cellulose and hydraulic cementitious materials on the rubber-plastic micro-powder also regulate its hydrophobic properties, while the distributed sodium sulfate accelerates the hydration reaction near the rubber-plastic micro-powder. This preparation method further improves the setting performance of the rubber-plastic micro-powder fluidized solid waste lightweight soil composition, and the performance retention after setting is also good.
[0071] In this application, after the wet rubber-plastic micropowder fluidized solid waste lightweight soil composition is prepared, it can be transported and poured using pipelines or concrete pump trucks. Moreover, since the rubber-plastic micropowder fluidized solid waste lightweight soil composition does not contain foam and there is no defoaming problem, it can also be transported by concrete mixer trucks and directly poured onto the project site via chutes.
[0072] The preparation method provided in this application is simple and efficient, and can be applied to large-scale preparation with simple adjustments. The resulting fluidized solid waste lightweight soil has good workability and can be cast in place on a large scale. The resulting rubber-plastic micro powder fluidized solid waste lightweight soil can also effectively meet the requirements for use as a filling material after hardening.
[0073] The following specific examples provide further details.
[0074] The method for preparing lightweight solid soil from rubber and plastic micropowder according to this application includes the following steps:
[0075] Rubber and plastic micro powder, hydroxyethyl methyl cellulose and some hydraulic cementitious materials are mixed, allowed to stand, and then additives are added and mixed to obtain a second mixture;
[0076] Then, solid waste base material and residual hydraulic cementitious material are added to the second mixture to obtain the third mixture;
[0077] The third mixture and water were mixed according to the water-to-solid ratio to obtain a wet rubber-plastic micropowder fluidized solid waste lightweight soil composition.
[0078] Among them, the specific surface area of the solid waste base material is not less than 200m². 2 / Kg; the particle size of hydroxyethyl methyl cellulose is 120μm; the mass ratio of hydraulic cementitious material to residual hydraulic cementitious material is 1:19.
[0079] Example 1
[0080] The rubber-plastic micropowder fluidized solid waste lightweight soil of Example 1 includes the following raw materials:
[0081] (1) Solid materials; solid materials include solid waste binder and rubber and plastic powder; solid waste binder is calculated by weight parts, including: 40 parts fly ash, 30 parts cement, 30 parts blast furnace slag powder, 1.5 parts triethanolamine, 1.5 parts sodium sulfate, and 0.05 parts hydroxyethyl methyl cellulose;
[0082] The volumetric content of rubber and plastic micro powder in solid materials is 65%;
[0083] The rubber and plastic micro powder is EPS micro powder with a particle size of 0.75mm;
[0084] (2) Water; the weight ratio of water to solid material is 0.65.
[0085] The wet rubber-plastic micropowder fluid solid waste lightweight soil composition of Example 1 was prepared by the provided preparation method. After standard curing for 7 days, the strength reached 0.73 MPa, and after 28 days, the strength reached 1.07 MPa.
[0086] Example 2
[0087] Example 2's rubber-plastic micropowder fluidized solid waste lightweight soil comprises the following raw materials:
[0088] (1) Solid materials; solid materials include solid waste binder and rubber and plastic powder; solid waste binder is calculated by weight parts, including: 50 parts fly ash, 10 parts cement, 40 parts blast furnace slag powder, 1.5 parts triethanolamine, 1.5 parts sodium sulfate, and 0.05 parts hydroxyethyl methyl cellulose;
[0089] The volumetric content of rubber and plastic micro powder in solid materials is 64%;
[0090] The rubber-plastic micro powder is a rubber micro powder with a particle size of 0.75 mm;
[0091] (2) Water; the weight ratio of water to solid material is 0.65.
[0092] The wet rubber-plastic micropowder fluidized solid waste lightweight soil composition of Example 2 was prepared by the provided preparation method. After standard curing for 7 days, the strength reached 0.92 MPa, and after 28 days, the strength reached 1.13 MPa.
[0093] Example 3
[0094] Example 3, a fluidized solid waste lightweight soil made of rubber and plastic micropowder, comprises the following raw materials:
[0095] (1) Solid materials; solid materials include solid waste binder and rubber and plastic powder; solid waste binder is calculated by weight parts, including: 40 parts fly ash, 30 parts cement, 30 parts blast furnace slag powder, 1.5 parts triethanolamine, 1.5 parts sodium sulfate, and 0.05 parts hydroxyethyl methyl cellulose;
[0096] The volumetric content of rubber and plastic micro powder in solid materials is 66%;
[0097] The rubber-plastic micro powder is a combination of EPS micro powder and rubber micro powder, both with a particle size of 0.75 mm, and the volume ratio of EPS micro powder to rubber micro powder is 1:9.
[0098] (2) Water; the weight ratio of water to solid material is 0.5.
[0099] The wet rubber-plastic micropowder fluidized solid waste lightweight soil composition of Example 3 was prepared by the provided preparation method. After standard curing for 7 days, the strength reached 1.18 MPa, and after 28 days, the strength reached 1.45 MPa.
[0100] Performance testing
[0101] The wet rubber-plastic micro-powder fluidized lightweight solid waste soil composition of Example 3, using fly ash as the solid waste base material, was molded into standard prism precast components. The standard precast components were subjected to 2 million cycles of cyclic loading and unloading at 15 kPa to conduct compressive fatigue performance tests, simulating traffic loads. The test results are as follows: Figure 1 As shown.
[0102] Through observation Figure 1 It can be observed that after 2 million cycles of the compressive fatigue resistance test, the cumulative displacement was 0.7507 mm and the cumulative deformation was 2.502 mm / m. Furthermore, the displacement curve and deformation curve maintained a basically linear relationship with the number of cycles. This indicates that the rubber-plastic micro-powder fluidized solid waste lightweight soil of Example 1 can still maintain good basic properties and elasticity under multiple load cycles, with little change in strength. It can undergo recoverable elastic deformation under traffic loads and play a good buffering role. After being used as a roadbed for filling, it can withstand the cyclic action of traffic loads, meet the compressive fatigue resistance requirements of multiple cyclic loads, and improve the service life of the road.
[0103] The rubber and plastic micro-powder fluidized solid waste lightweight soil provided in this application has good performance. Its compressive strength can meet the requirements for roadbed filling or filling. It also has the characteristics of compressive fatigue resistance, which is conducive to maintaining performance in long-term use. It can realize the resource reuse of waste resources, solve the disposal problem, and realize the comprehensive utilization of solid waste materials for roads. It is of great significance to environmental protection and infrastructure construction.
[0104] It should be understood that the application of this application is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of this application.
Claims
1. A lightweight solid waste material made from rubber and plastic micropowder, characterized in that, Including the following raw materials: (1) Solid materials; Solid materials include solid waste binders and rubber and plastic powders; The solid waste binder, calculated by weight, includes: 40-60 parts solid waste base material, 50-60 parts hydraulic cementitious material, 0.3-3 parts admixture, and 0.03-0.05 parts hydroxyethyl methyl cellulose; The volume fraction of the rubber and plastic micro powder in the solid material is 10%-70%; (2) Water; The weight ratio of water to solid material is 0.5-0.7:1; The particle size of the hydroxyethyl methyl cellulose is 80-160 μm; The additive is a combination of triethanolamine and sodium sulfate; The solid waste base material is one of the following: fly ash, desulfurization ash, desulfurization gypsum, red mud, alkali slag, ceramic polishing slag, carbide slag, tailings slag, phosphogypsum, and stone sawing mud; The specific surface area of the solid waste base material is not less than 200 m². 2 / Kg.
2. The lightweight solid waste material made of rubber and plastic micropowder according to claim 1, characterized in that, The rubber-plastic micro powder is one or more of waste foamed PU micro powder, EPS micro powder and rubber micro powder; the volume content of the rubber-plastic micro powder is 20%-70%.
3. The lightweight solid waste material made of rubber and plastic micropowder according to claim 2, characterized in that, The particle size of the rubber and plastic micro powder is 0.5-1mm.
4. The lightweight solid waste material made of rubber and plastic micropowder according to claim 3, characterized in that, The rubber-plastic micro powder is a combination of EPS micro powder and rubber micro powder, and the volume ratio of EPS micro powder to rubber micro powder is 1:
9.
5. The lightweight solid waste material made of rubber and plastic micropowder according to claim 1, characterized in that, The hydraulic cementitious material is a combination of cement and blast furnace slag powder, wherein the weight ratio of cement to blast furnace slag powder is 1:1-4.
6. A method for preparing lightweight solid waste fluidized bed of rubber and plastic micropowder as described in any one of claims 1-5, characterized in that, Includes the following steps: The rubber and plastic micro powder, hydroxyethyl methyl cellulose and a portion of hydraulic cementitious material are mixed, allowed to stand, and then the additives are added and mixed to obtain a second mixture. Then, the solid waste base material and the remaining hydraulic cementitious material are added to the second mixture to obtain the third mixture; The third mixture and the water were mixed according to the water-to-solid ratio to obtain a wet rubber-plastic micropowder fluidized solid waste lightweight soil composition; The particle size of the hydroxyethyl methyl cellulose is 80-160 μm; The mass ratio of the partial hydraulic cementitious material to the remaining hydraulic cementitious material is 1:19; The additive is a combination of triethanolamine and sodium sulfate.