Anti-dispersion high-toughness in-situ polymerization grouting material, preparation method and application thereof

Abstract

The application belongs to the technical field of geotechnical engineering, and more particularly relates to an anti-dispersion high-toughness in-situ polymerization grouting material and a preparation method and application thereof. The application takes silicate cement as an inorganic base material, and constructs an "in-situ polymerization-interfacial bridging" synergistic regulation system by introducing acrylamide monomers and sodium lignosulfonate. In view of the technical bottleneck that traditional grouting materials are prone to dispersion loss and have large brittleness in a dynamic water environment, sodium lignosulfonate is used as a dynamic oxidation-reduction initiator to induce in-situ polymerization of acrylamide in a cement hydration environment, and a high-molecular polyacrylamide long chain is generated. At the same time, the interfacial bridging effect of the sodium lignosulfonate molecules is used to promote the formation of chemical anchoring between the organic polymer chain and the inorganic hydration product, so as to construct an organic-inorganic interpenetrating network structure at a microscale. This structure not only can improve the anti-dispersion property of the slurry through dynamic rheological response, but also can significantly enhance the ductility and toughness of the cementing body through the energy consumption effect of the organic component.

Description

Technical Field

[0001] This invention belongs to the field of geotechnical engineering technology, and more specifically relates to an anti-dispersion, high-toughness in-situ polymer grouting material, its preparation method, and its application. Background Technology

[0002] With the continuous growth in demand for the development and utilization of mineral resources such as coal and metals, as well as underground space, shallow resources are becoming increasingly depleted after years of intensive mining. Moving into deeper strata has become an inevitable trend in engineering construction and resource development. Currently, the operating depth of many core mines and underground projects in China has exceeded 1,000 meters. Against this backdrop, the engineering safety issues brought about by the complex geomechanical environment of deep underground areas, such as high ground stress, high osmotic pressure, and high ground temperature, are becoming increasingly prominent, placing higher demands on the stability analysis and safety control of deep underground engineering projects.

[0003] The coupling effect of strong disturbances and high ground stress during deep mining and construction exacerbates the damage and deterioration of the surrounding rock structure. Especially in deep, water-rich strata, fractured rock masses easily form water-conducting channels, inducing water inrush disasters. Deep groundwater typically has high osmotic pressure and dynamic flow velocity; the harsh dynamic water environment not only intensifies the erosion and expansion of fractures but also causes continuous mechanical erosion and deterioration of the surrounding rock support structure. Therefore, exploring how to effectively seal water-conducting fractures and enhance the bearing capacity and impermeability of the surrounding rock structure under conditions of high ground stress and high osmotic pressure dynamic water has become a critical scientific problem urgently needing to be solved in deep geotechnical engineering construction.

[0004] Engineering practice has shown that grouting technology has significant advantages in improving the properties of deep, water-rich, fractured rock masses. This technology utilizes hydraulic or pneumatic forces to inject grout into rock fissures, repairing the fissures, displacing water, and cementing the rock to form a high-strength, unified mass. Among various grouting materials, cement-based grouting materials, with their significant advantages of low cost, convenient preparation, and high mechanical strength, have become the preferred material for extending tunnel service life and improving the overall integrity of rock.

[0005] However, conventional cement-based grouting materials exhibit significant application defects in deep, water-rich, and high-stress environments, presenting a fundamental contradiction: a difficulty in simultaneously achieving optimal fluidity, anti-dispersion properties, and cementitious toughness. On the one hand, while high fluidity facilitates grout pumping and deep micro-crack penetration, it is highly susceptible to loss and dispersion under dynamic water scouring, leading to grouting failure. Improving scouring resistance by adding flocculants or anti-dispersion agents often comes at the cost of a dramatic increase in grout viscosity and a significant decrease in injectability. On the other hand, traditional cement-based binders are inherently brittle materials, prone to brittle fracture under deep, high-stress, and frequent dynamic disturbances, making it difficult to maintain long-term support effectiveness.

[0006] To address these issues, traditional methods often employ the addition of polymers for physical blending or surface modification. However, traditional polymer-modified materials often face bottlenecks such as high cost, difficulty in dispersing polymers in cement slurry, and weakening of the organic-inorganic interface due to simple physical mixing, making it difficult to fundamentally achieve a synergistic improvement in rheology and toughness.

[0007] Therefore, breaking through the limitations of traditional physical blending and developing new grouting materials with the characteristics of "bulk toughening" and "dynamic flow control" has become an urgent need in the interdisciplinary field of geotechnical engineering and materials science. Summary of the Invention

[0008] The purpose of this invention is to provide an anti-dispersion, high-toughness in-situ polymeric grouting material, its preparation method, and its application. Specifically, based on an in-situ polymeric network construction strategy, by achieving in-situ growth of organic chains and chemical anchoring of the inorganic matrix in a cement-based system, an organic-inorganic interpenetrating network is synergistically constructed, achieving a synergistic effect of "anti-dispersion" and "high toughness". This not only effectively solves the problem of grout dispersion and loss in dynamic water environments, but also significantly enhances the ductile failure characteristics and strain tolerance of the cementitious body, ensuring the long-term stability of deep rock masses. It provides a high-performance, high-reliability protection solution for reinforcement projects under extreme conditions such as deep water-rich strata and high-stress mines.

[0009] To achieve the above objectives, the present invention provides the following solution: One of the technical solutions of this invention is to provide an anti-dispersion, high-toughness in-situ polymerized grouting material, which, by mass, comprises: 100 parts cement, 40-60 parts water, 2-8 parts acrylamide, 0.1-0.2 parts sodium lignosulfonate, 0.02-0.12 parts potassium persulfate, 0.01-0.08 parts sodium bisulfite, and 0.002-0.016 parts methylenebisacrylamide.

[0010] The anti-dispersion, high-toughness in-situ polymeric grouting material provided by this invention abandons the traditional physical blending approach. Through an in-situ polymeric network construction strategy, sodium lignosulfonate is introduced as a dynamic redox initiator and interfacial bridging molecule. This not only achieves dynamic adjustment of the grout rheological behavior (static thickening, shear viscosity reduction), but also significantly enhances the ductile failure characteristics and strain tolerance of the cementitious body by synergistically constructing an organic-inorganic interpenetrating network in a cement environment. This significantly improves the material's anti-dispersion ability and surrounding rock reinforcement effect under dynamic water scouring and high-stress disturbance environments, providing a dynamic flow control, underwater scouring resistance, and high-toughness crack resistance grouting solution for reinforcement projects in complex environments such as deep water-rich strata and high-stress mines.

[0011] Furthermore, by weight, the raw materials include: 100 parts cement, 40-60 parts water, 2-8 parts acrylamide, 0.1-0.2 parts sodium lignosulfonate, 0.025-0.1 parts potassium persulfate, 0.015-0.06 parts sodium bisulfite, and 0.0025-0.01 parts methylenebisacrylamide.

[0012] Optionally, by weight, the raw materials include: 100 parts cement, 50 parts water, 8 parts acrylamide, 0.2 parts sodium lignosulfonate, 0.1 parts potassium persulfate, 0.06 parts sodium bisulfite, and 0.01 parts methylenebisacrylamide.

[0013] Furthermore, the cement is PO 42.5 ordinary Portland cement.

[0014] The second technical solution of the present invention provides a method for preparing the above-mentioned anti-dispersion high-toughness in-situ polymerization grouting material, the steps of which include: Acrylamide, sodium lignosulfonate, potassium persulfate, sodium bisulfite, and methylenebisacrylamide were dissolved in a portion of water to obtain a mixed solution. The mixture, cement, and the remaining water are mixed and then subjected to low-speed premixing and high-speed stirring in sequence to obtain the anti-dispersion high-toughness in-situ polymer grouting material.

[0015] Furthermore, the preparation steps of the mixture include: adding acrylamide to a portion of water and stirring to dissolve it; then adding sodium lignosulfonate and stirring to dissolve it; then adding potassium persulfate, sodium bisulfite, and methylenebisacrylamide and stirring to mix evenly to obtain the mixture.

[0016] Furthermore, the amount of water in this portion is 10-80 wt% of the total water usage.

[0017] Furthermore, the low-speed premixing time is 120s and the rotation speed is 300rpm.

[0018] Furthermore, the rapid stirring time is 120 seconds and the rotation speed is 500 rpm.

[0019] The third technical solution of the present invention provides an application of the above-mentioned anti-dispersion high-toughness in-situ polymer grouting material in the field of deep water-rich strata, high-stress mines and surrounding rock reinforcement projects in dynamic water environments.

[0020] The present invention discloses the following technical effects: This invention provides a high-toughness, anti-dispersion in-situ polymeric grouting material. By introducing in-situ polymeric monomers and functional interface bridging molecules into a cement-based system, the grout undergoes full-scale modification from microscopic network construction to macroscopic rheological toughness. This approach utilizes the in-situ generated organic-inorganic interpenetrating network to significantly enhance the material's energy absorption capacity and strain tolerance, altering the brittle fracture mode of cement-based materials. Simultaneously, by utilizing the dynamic rheological properties regulated by sodium lignosulfonate, the grout rapidly thickens to resist erosion under static conditions while maintaining good permeability under shear stress. This significantly improves the material's retention rate under dynamic water erosion conditions and its reinforcement effect on deep fractured rock masses, providing high-performance, high-toughness safety assurance for underground engineering construction under high ground stress and high permeability pressure environments. Attached Figure Description

[0021] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 The curves show the apparent viscosity of the grouting materials in Examples 1-4 and Comparative Examples 1-3 as a function of shear rate.

[0022] Figure 2 The mass retention rate of the grouting materials in Examples 1-4 and Comparative Examples 1-3 under dynamic water scouring.

[0023] Figure 3 The diagram shows the underwater anti-dispersion mechanism of the grouting materials of Example 1 (in-situ polymerized grouting material) and Comparative Example 1 (conventional grouting material).

[0024] Figure 4 The stress-strain curves are for the hardened stone bodies obtained from the grouting materials of Examples 1-4 and Comparative Examples 1-3.

[0025] Figure 5 This is a SEM image of the grouting material after curing in Comparative Example 1.

[0026] Figure 6 This is a SEM image of the grouting material after curing in Example 1. Detailed Implementation

[0027] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0028] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Any stated value or intermediate value within a stated range, as well as each smaller range between any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0029] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0030] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0031] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0032] Unless otherwise specified, all raw materials and reagents involved in the specific embodiments of this invention are commercially available products.

[0033] Among them, the cement was purchased from Zhucheng Yangchun Cement Co., Ltd. as P.O42.5 cement; acrylamide, sodium lignosulfonate, potassium persulfate, sodium bisulfite, and methylenebisacrylamide were all purchased from Shanghai Maclean Biochemical Technology Co., Ltd.

[0034] Unless otherwise specified, room temperature and normal temperature in the specific embodiments of this invention refer to 20-30℃.

[0035] It should be noted that any aspects not described in detail in this invention are conventional practices in the field and are not the focus of this invention.

[0036] To address the problems of traditional cement-based grouting materials being prone to cracking and failure due to their brittle nature in deep, water-rich, and high-stress environments, and easily becoming lost and dispersed in dynamic water conditions, this invention proposes a high-toughness, anti-dispersion in-situ polymeric grouting material. By introducing acrylamide (AM) as a polymerization unit and utilizing sodium lignosulfonate (SLS) as a dynamic redox initiator and interfacial bridging molecule, in-situ growth of organic chains is induced in the cement hydration environment, constructing an organic-inorganic interpenetrating network (IPN). This not only enhances the energy absorption capacity and toughness of the cementitious structure through the nucleation and anchoring effects of the polymer network, but also strengthens the grout's anti-dispersion properties through its dynamic rheological response characteristics. To overcome the difficulties in controlling the polymerization rate and poor interfacial compatibility of polymers in strongly alkaline environments, this invention employs a precise ratio of sodium lignosulfonate to the redox initiation system, achieving synergy between the polymerization reaction and the hydration process. This ensures the uniform construction of the organic network in the matrix and significantly improves the material's service durability under dynamic water erosion and complex stress environments.

[0037] In some specific embodiments, the present invention provides an anti-dispersion, high-toughness in-situ polymeric grouting material, which, by weight, comprises: 100 parts cement (PO 42.5 ordinary Portland cement), 40-60 parts water, 2-8 parts acrylamide, 0.1-0.2 parts sodium lignosulfonate, 0.02-0.12 parts potassium persulfate, 0.01-0.08 parts sodium bisulfite, and 0.002-0.016 parts methylenebisacrylamide.

[0038] In some alternative embodiments, the mass ratio of acrylamide, potassium persulfate, sodium bisulfite, and methylenebisacrylamide is 1:(0.01~0.015):(0.005~0.01):(0.001~0.002).

[0039] In some preferred embodiments, the mass ratio of acrylamide, potassium persulfate, sodium bisulfite and methylenebisacrylamide is 1:0.0125:0.0075:0.00125.

[0040] In some preferred embodiments, the amount of acrylamide is 4 to 8 parts, and the amount of sodium lignosulfonate is 0.15 to 0.2 parts.

[0041] In some preferred embodiments, the amount of acrylamide is 8 parts and the amount of sodium lignosulfonate is 0.2 parts.

[0042] If the weight percentage of acrylamide is too low, the density of the organic network generated in situ within the system will be insufficient, making it difficult to form a continuous interpenetrating network structure at the microscale. This will not significantly improve the strain tolerance and toughness of the aggregate, and the effect on regulating the dynamic rheology of the slurry will be insignificant. Conversely, if the weight percentage of acrylamide is too high, the excessive organic chains will over-encapsulate the unhydrated cement particles, creating a physical shielding effect that severely hinders the growth of hydration products. This will result in a loose internal structure and a significant reduction in mechanical strength, while also causing the initial viscosity of the slurry to be too high, thus reducing its permeability.

[0043] If the amount of sodium lignosulfonate is too small, the initiation efficiency in the system will be low, the acrylamide polymerization will be insufficient, and there will be a lack of sufficient interfacial bridging molecules to promote the chemical anchoring of the organic-inorganic phase, resulting in limited reinforcement effect. If the amount of sodium lignosulfonate is too large, due to its strong retarding effect, it will significantly prolong the initial and final setting time of cement, and may even cause the material to be washed away and fail in a dynamic water environment due to slow hardening. At the same time, high concentrations of sodium lignosulfonate may change the polymerization kinetics and affect the uniformity of the organic network.

[0044] This invention uses silicate cement as the inorganic base material and constructs an "in-situ polymerization-interfacial bridging" synergistic regulation system by introducing acrylamide (AM) monomers and sodium lignosulfonate (SLS). Addressing the technical bottlenecks of traditional grouting materials' easy dispersion and loss in dynamic water environments and their high brittleness, sodium lignosulfonate is used as a dynamic redox initiator to induce in-situ polymerization of acrylamide in the cement hydration environment, generating long chains of high-molecular-weight polyacrylamide. Simultaneously, the interfacial bridging effect of sodium lignosulfonate molecules promotes chemical anchoring between the organic polymer chains and inorganic hydration products (such as CSH gel), thereby constructing an organic-inorganic interpenetrating network (IPN) structure at the microscale. This structure not only improves the anti-dispersion properties of the grout through dynamic rheological response (static thickening, shear viscosity reduction) but also significantly enhances the ductility and toughness of the binder through the energy-consuming effect of the organic components.

[0045] To address the challenges of controlling polymer polymerization rates and poor interfacial compatibility in strongly alkaline cement environments, this invention achieves a synergistic match between polymerization kinetics and cement hydration processes by limiting the ratio of sodium lignosulfonate to the redox initiation system. This ensures the uniform construction of the polymer network before and after the initial setting of the cement grout. Through the synergistic effect of physical shielding and chemical bonding, the components endow the material with excellent mechanical tolerance and dynamic flow control capabilities in deep, water-rich, and high-stress disturbance environments, providing a high-strength, tough, and erosion-resistant grouting solution for surrounding rock reinforcement in complex geological environments.

[0046] In some specific embodiments, the present invention provides a method for preparing an anti-dispersion, high-toughness in-situ polymerized grouting material, the steps of which include: S1. Prepare the raw materials according to the above proportions.

[0047] S2. Mix acrylamide with water accounting for 10-80 wt% of the total water volume, stir for 3 minutes to fully dissolve the monomer, then add sodium lignosulfonate, and stir magnetically at 200 rpm for 2 minutes to disperse until completely dissolved and a homogeneous system is formed. Finally, add potassium persulfate, sodium bisulfite and methylenebisacrylamide, and stir magnetically at 300 rpm for 2 minutes to fully mix them to obtain a mixture.

[0048] S3. Mix the mixture obtained in step S2, cement, and the remaining water, following the steps of "low-speed premixing, scraping and remixing, and rapid strengthening". First, stir at low speed (300 rpm) for 120 seconds to initially mix the materials. Then, stop stirring and use a scraper to scrape the slurry off the mixing paddle and the container wall (takes about 15 seconds). Finally, restart rapid stirring (500 rpm) for 120 seconds to make the system completely uniform and obtain the anti-dispersion high-toughness in-situ polymer grouting material.

[0049] This invention proposes an anti-dispersion, high-toughness in-situ polymeric grouting material. By introducing in-situ polymeric components and interfacial bridging components, it achieves modification from the molecular scale to the macroscopic properties. This not only solves the brittleness problem of traditional cement-based materials, but also provides a grouting solution with dynamic flow control and high toughness and crack resistance for deep engineering by constructing a stable organic-inorganic interpenetrating network.

[0050] Example 1 The preparation steps of a high-toughness, anti-dispersion in-situ polymerized grouting material include: S1. Prepare the following raw materials according to their weight: 100 parts cement (PO 42.5 ordinary Portland cement), 50 parts water, 4 parts acrylamide, 0.1 parts sodium lignosulfonate, 0.05 parts potassium persulfate, 0.03 parts sodium bisulfite, and 0.005 parts methylenebisacrylamide.

[0051] S2. Mix acrylamide with water accounting for 50 wt% of the total water volume, stir for 3 minutes to fully dissolve the solid monomer, then add sodium lignosulfonate, and stir magnetically at 200 rpm for 2 minutes to disperse until completely dissolved and a homogeneous system is formed. Finally, add potassium persulfate, sodium bisulfite and methylenebisacrylamide, and stir magnetically at 300 rpm for 2 minutes to fully mix them to obtain a mixture.

[0052] S3. Mix the mixture obtained in step S2, cement, and the remaining water, following the steps of "low-speed premixing, scraping and remixing, and rapid strengthening". First, stir at low speed (300 rpm) for 120 seconds to initially mix the materials. Then, stop stirring for 15 seconds and use a scraper to scrape the slurry off the stirring paddle and the container wall. Finally, restart rapid stirring (500 rpm) for 120 seconds to make the system completely uniform and obtain the anti-dispersion high-toughness in-situ polymer grouting material.

[0053] Example 2 The only difference from Example 1 is that the amount of sodium lignosulfonate used is 0.2 parts.

[0054] Example 3 Compared with Example 1, the difference lies in the following mass distribution of the raw materials: 100 parts cement (PO 42.5 ordinary Portland cement), 50 parts water, 8 parts acrylamide, 0.1 parts sodium lignosulfonate, 0.1 parts potassium persulfate, 0.06 parts sodium bisulfite, and 0.01 parts methylenebisacrylamide.

[0055] Example 4 Compared with Example 1, the difference lies in the following mass distribution of the raw materials: 100 parts cement (PO 42.5 ordinary Portland cement), 50 parts water, 8 parts acrylamide, 0.2 parts sodium lignosulfonate, 0.1 parts potassium persulfate, 0.06 parts sodium bisulfite, and 0.01 parts methylenebisacrylamide.

[0056] Comparative Example 1 The preparation steps for grouting materials include: S1. Prepare the following raw materials according to their weight: 100 parts cement (PO 42.5 ordinary Portland cement), 50 parts water.

[0057] S2. Mix cement and water. First, stir at low speed (300 rpm) for 120 seconds to initially mix the materials. Then, stop stirring for 15 seconds and use a scraper to scrape the slurry off the mixing paddle and the container wall. Finally, restart the stirring at high speed (500 rpm) for 120 seconds to make the system completely homogeneous and obtain the grouting material.

[0058] Comparative Example 2 The only difference from Example 1 is that the amount of sodium lignosulfonate used is 0 parts.

[0059] Comparative Example 3 Compared with Example 1, the difference lies in the following mass distribution of the raw materials: 100 parts cement (PO 42.5 ordinary Portland cement), 50 parts water, 8 parts acrylamide, 0 parts sodium lignosulfonate, 0.1 parts potassium persulfate, 0.06 parts sodium bisulfite, and 0.01 parts methylenebisacrylamide.

[0060] Test case After the grouting materials prepared in the examples and comparative examples were left to stand for 1 minute, they were poured into the corresponding molds and placed in a curing box with a curing temperature of 20°C and a humidity of 98% for curing. After reaching the corresponding curing age, they were taken out for testing.

[0061] Figure 1 The graph shows the apparent viscosity of the grouting materials in Examples 1-4 and Comparative Examples 1-3 as a function of shear rate. As can be seen from the graph, the apparent viscosity of Comparative Example 1 (pure cement grout) is low and does not change significantly with shear rate. The apparent viscosity of Comparative Examples 2 and 3 (acrylamide monomer only) is higher than that of Comparative Example 1, reflecting the physical resistance of the generated polymer network to grout flow. Examples 1 to 4, due to the introduction of the in-situ polymerization and sodium lignosulfonate (SLS) synergistic system, exhibit more significant shear thinning (i.e., shear viscosity reduction) characteristics. At low shear rates, SLS promotes the interweaving and interfacial bonding of polymer long chains and cement particles, forming a strong spatial network structure, giving the grout a higher initial viscosity (thickening upon standing). As the shear rate increases, the polymer molecular chains deentangle, and SLS exerts its water-reducing and electrostatic dispersing effects, releasing the trapped water and rapidly decreasing the apparent viscosity. This dynamic rheological property gives the grouting material good fluidity and injectability during the pumping stage, and it can quickly thicken after being injected into the fissure and left to stand, effectively resisting the erosion of moving water.

[0062] Figure 2 The mass retention rate of the grouting materials in Examples 1-4 and Comparative Examples 1-3 under dynamic water scouring.

[0063] Figure 3 The diagram shows the underwater anti-dispersion mechanism of the grouting materials of Example 1 (in-situ polymerized grouting material) and Comparative Example 1 (conventional grouting material).

[0064] Depend on Figure 2 and Figure 3It can be seen that Comparative Example 1, without any added polymer components, is highly susceptible to dispersion and loss under flowing water, with a mass retention rate of only 32.51%. Comparative Examples 2 and 3, after introducing acrylamide alone, saw their mass retention rates increase to 59.19% and 87.86%, respectively. This indicates that the in-situ generated polymer network has a basic physical encapsulation effect on resisting water flow erosion. In contrast, the anti-dispersion ability of the examples was further synergistically enhanced. For example, Example 4, by introducing 0.2 parts of SLS based on Comparative Example 3, saw its mass retention rate further jump from 87.86% to 94.35%. Figure 3 As can be seen from the underwater anti-dispersion mechanism diagram, this invention utilizes the interfacial bridging effect of sodium lignosulfonate to enable the in-situ generated organic macromolecular chains to more firmly entangle and anchor discrete cement particles, forming a highly dense flocculent structure. This enhanced organic-inorganic three-dimensional network not only locks in free water within the system but also greatly enhances the cohesive force between cementitious materials, thus exhibiting excellent underwater erosion and anti-dispersion performance on a macroscopic scale.

[0065] Figure 4 The figures show the stress-strain curves of the hardened stone bodies obtained from the grouting materials of Examples 1-4 and Comparative Examples 1-3. As can be seen from the figures, Comparative Example 1 exhibits typical brittle fracture characteristics; after reaching the peak stress, the curve drops vertically instantaneously, indicating abrupt failure with extremely low strain tolerance. While Comparative Examples 2 and 3 show a certain stress plateau after the peak stress, the lack of an effective interfacial bridging agent results in weak interfacial bonding between the pure polymer network and the inorganic framework, leading to lower peak stresses and a rapid decrease in residual bearing capacity with increasing strain. In contrast, the curves of Examples 1 to 4 show more pronounced strain hardening and an extremely long ductile failure stage after reaching the yield point. This is mainly due to the crucial role played by the organic-inorganic interpenetrating network (IPN) constructed within the matrix. During deformation under load, the flexible polymer macromolecular chains are firmly bonded to the inorganic framework through the chemical anchoring effect of sodium lignin sulfonate, absorbing a large amount of deformation energy through the stretching, slippage of the macromolecular chain segments, and the debonding friction of the interface. This "high toughness" effect effectively inhibits the rapid unstable propagation of microcracks, significantly improves the material's ultimate strain and deformation adaptability, and enables it to cope with the high ground stress and frequent dynamic disturbances of deep surrounding rocks.

[0066] Figure 5 This is a SEM image of the grouting material after curing in Comparative Example 1.

[0067] Figure 6 This is a SEM image of the grouting material after curing in Example 1.

[0068] Depend on Figures 5-6 It can be seen that, Figure 5The microstructure of the ordinary grouting material in Comparative Example 1 is relatively loose, mainly composed of needle-like ettringite (AFt), flake-like calcium hydroxide (CH), and amorphous CSH gel discretely stacked, with weak interfacial bonding. However, from... Figure 6 As can be clearly observed, within the in-situ polymerized grouting material of Example 1 of this invention, a large number of organic polymer films and fibrous bridging structures are generated between the hydration products. The organic network constructed by sodium lignosulfonate and polyacrylamide is interspersed within the inorganic framework, playing a significant role in "interfacial bridging" and "microscopic stitching." This structure firmly connects the originally loose hydration products into a tight whole, fully demonstrating from a microscopic mechanism the improvement in macroscopic anti-dispersion ability and the significant leap in mechanical toughness of the material of this invention.

[0069] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0070] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high-toughness, anti-dispersion in-situ polymerizable grouting material, characterized in that, By weight, the raw materials include: 100 parts cement, 40-60 parts water, 2-8 parts acrylamide, 0.1-0.2 parts sodium lignosulfonate, 0.02-0.12 parts potassium persulfate, 0.01-0.08 parts sodium bisulfite, and 0.002-0.016 parts methylenebisacrylamide.

2. The anti-dispersion, high-toughness in-situ polymerization grouting material as described in claim 1, characterized in that, By weight, the raw materials include: 100 parts cement, 40-60 parts water, 2-8 parts acrylamide, 0.1-0.2 parts sodium lignosulfonate, 0.025-0.1 parts potassium persulfate, 0.015-0.06 parts sodium bisulfite, and 0.0025-0.01 parts methylenebisacrylamide.

3. The anti-dispersion, high-toughness in-situ polymerization grouting material as described in claim 1, characterized in that, By weight, the raw materials include: 100 parts cement, 50 parts water, 8 parts acrylamide, 0.2 parts sodium lignosulfonate, 0.1 parts potassium persulfate, 0.06 parts sodium bisulfite, and 0.01 parts methylenebisacrylamide.

4. The anti-dispersion, high-toughness in-situ polymerization grouting material as described in claim 1, characterized in that, The cement is P.O42.5 ordinary Portland cement.

5. A method for preparing the anti-dispersion, high-toughness in-situ polymerized grouting material according to any one of claims 1-4, characterized in that the step... include: Acrylamide, sodium lignosulfonate, potassium persulfate, sodium bisulfite, and methylenebisacrylamide were dissolved in a portion of water to obtain a mixed solution. The mixture, cement, and the remaining water are mixed and then subjected to low-speed premixing and high-speed stirring in sequence to obtain the anti-dispersion high-toughness in-situ polymer grouting material.

6. The preparation method according to claim 5, characterized in that, The preparation steps of the mixture include: adding acrylamide to a portion of water and stirring to dissolve it; then adding sodium lignosulfonate and stirring to dissolve it; then adding potassium persulfate, sodium bisulfite, and methylenebisacrylamide and stirring to mix evenly to obtain the mixture.

7. The preparation method according to claim 5, characterized in that, The amount of water mentioned is 10-80 wt% of the total water usage.

8. The preparation method according to claim 5, characterized in that, The low-speed premixing time is 120s, and the rotation speed is 300rpm.

9. The preparation method according to claim 5, characterized in that, The rapid stirring time is 120 seconds and the rotation speed is 500 rpm.

10. The application of the anti-dispersion high-toughness in-situ polymer grouting material according to any one of claims 1-4 in the field of deep water-rich strata, high-stress mines and surrounding rock reinforcement engineering in dynamic water environments.

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