Floor mudstone rapid hardening material and preparation method and application thereof

Abstract

The invention belongs to the technical field of mining materials, and particularly relates to a floor mudstone rapid hardening material and a preparation method and application thereof. The rapid hardening material for the bottom plate mudstone is prepared from the following components in parts by weight: 30 to 50 parts of sulphoaluminate cement, 20 to 30 parts of Portland cement, 30 to 40 parts of gypsum, 1 to 3 parts of lime, 0.5 to 2 parts of a water reducing agent, 1 to 4 parts of a sacrificial agent, 0.5 to 1 part of an early strength agent, 0.1 to 0.5 part of a retarder, 1 to 3 parts of fibers and 40 to 60 parts of water, the sacrificial agent comprises sodium tripolyphosphate, hexadecyl trimethyl ammonium bromide, citric acid and an aluminate coupling agent. The rapid hardening material for the bottom plate mudstone is mixed and stirred with softened aluminum soil mudstone of a bottom plate of a coal mine tunnel, a reinforcing layer with high strength and good toughness and water resistance can be rapidly formed, and normal passing of constructors and equipment is guaranteed.

Description

Technical Field

[0001] The present invention belongs to the technical field of mining materials, and particularly relates to a rapid hardening material for floor mudstone, a preparation method thereof, and an application thereof. Background Art

[0002] During the process of coal mine safety production, the stability of the roadway floor is an important factor for the daily passage and operation of staff and equipment. However, the composition of some roadway floors is mainly bauxitic mudstone, which has the characteristics of low strength and water softening. When facing roof seepage water, groundwater seepage, spraying water or construction operation water, etc., the mudstone absorbs water and quickly collapses, forming mud pits with different depths, seriously affecting the passage of personnel and equipment. Therefore, it is imperative to improve and reinforce bauxitic mudstone to enhance the stability of the roadway floor.

[0003] At present, the common treatment methods for the softening of bauxitic floor mudstone mainly include cleaning the mudstone and hardening it with concrete, electrochemical slurry penetration grouting reinforcement, mixing hardening materials with mudstone, etc. For example:

[0004] Chinese Patent Document CN117569843 A discloses a method for roadway tunneling and support in soft mudstone bodies. By electroosmosis method, CaCl2 solution and Na2SiO3 solution are respectively injected into the soft rock, so that Ca 2+ ions are exchanged with Fe 3+ ions in the mudstone, and a pozzolanic reaction occurs with the Na2SiO3 solution, thereby improving the strength of the mudstone. However, the overall construction process is relatively complex and is not suitable for the reinforcement application of bauxitic floor softening mudstone.

[0005] Chinese Patent Document CN101260639A discloses a method for rapidly reinforcing and treating the mudstone mud of the roadway floor by using fly ash-lime and civil engineering geocells. 50-80% of the mud, 10-20% of slaked lime and 10-30% of fly ash are mixed and stirred evenly to obtain a mud solidified body filler with a certain strength, and then these solidified body fillers are filled in the expanded civil engineering geocells to form a temporary road for unpaved roadways. However, the strength of the mud solidified body is only 1.78 MPa, which does not meet the passing requirements of large equipment.

[0006] Therefore, an improved technical solution is needed to address the deficiencies of the above-mentioned existing technologies. Summary of the Invention

[0007] The purpose of the present invention is to provide a rapid hardening material for floor mudstone, a preparation method thereof, and an application thereof, which helps to solve or improve the problem of softening of bauxitic floor mudstone and enhance the stability of the roadway floor.

[0008] To achieve the above object, the present invention provides the following technical solution: A rapid hardening material for floor mudstone. By weight, the rapid hardening material for floor mudstone comprises the following components in parts by weight: 30 - 50 parts of sulfoaluminate cement, 20 - 30 parts of portland cement, 30 - 40 parts of gypsum, 1 - 3 parts of lime, 0.5 - 2 parts of water reducing agent, 1 - 4 parts of sacrificial agent, 0.5 - 1 part of early strength agent, 0.1 - 0.5 part of retarder, 1 - 3 parts of fiber, and 40 - 60 parts of water; the sacrificial agent comprises sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid, and aluminate coupling agent.

[0009] Preferably, by weight, the sacrificial agent comprises: 20 - 25 parts of sodium tripolyphosphate, 0.25 - 0.5 part of cetyltrimethylammonium bromide, 5 - 10 parts of citric acid, and 20 - 25 parts of aluminate coupling agent.

[0010] Preferably, the sacrificial agent is obtained by mixing and grinding sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid, and aluminate coupling agent; the particle size of the sacrificial agent < 20μm.

[0011] Preferably, the sulfoaluminate cement is 72.5 calcium sulfoaluminate binder; the portland cement is P.O 42.5 ordinary portland cement.

[0012] Preferably, the gypsum is natural gypsum with a fineness of 600 mesh; the lime is quicklime with a fineness of 600 mesh.

[0013] Preferably, the water reducing agent is a naphthalene - based water reducing agent with a water reducing rate ≥ 20%; the early strength agent is aluminum sulfate with an industrial - grade purity; the retarder is sodium gluconate with an industrial - grade purity; the fiber is glass fiber with a length of 3 - 6mm.

[0014] The present invention also provides a preparation method of the above - mentioned rapid hardening material for floor mudstone, which adopts the following technical solution: The preparation method of the rapid hardening material for floor mudstone as described above comprises the following steps: Pour the sulfoaluminate cement, portland cement, gypsum, lime, water reducing agent, sacrificial agent, early strength agent, retarder, and fiber into a stirring bucket, add water in proportion, and mix evenly to obtain the rapid hardening material for floor mudstone.

[0015] Preferably, during mixing, use a hand - held pneumatic stirrer to stir at a speed of 120 - 150r / min for 0.8 - 1.5min, and then stir at a speed of 240 - 360r / min for 0.8 - 1.5min.

[0016] The present invention also provides a construction method for strengthening the floor mudstone. The construction method for strengthening the floor mudstone in the embodiments of the present invention includes the following steps: (1) Stir the softened mudstone on the floor with a hand-held pneumatic stirrer at a first rotation speed, and supplement water to keep the water content at 25%-35%, and then stir at a second rotation speed to mix the mudstone and water evenly to obtain a mudstone slurry; (2) Stir the mudstone slurry with a hand-held pneumatic stirrer at a third rotation speed, and continuously add the above-mentioned floor mudstone rapid hardening material at the same time, and then stir at a fourth rotation speed to mix evenly to obtain a mixed slurry; (3) Insert a pneumatic vibrating rod into the mixed slurry to vibrate it densely, and then level the surface with a spade.

[0017] Preferably, in step (2), the mass ratio of the floor mudstone rapid hardening material to the mudstone slurry is 1:(2-4); the first rotation speed is 120-150 r / min, and the stirring time at the first rotation speed is 1.5-2.5 min; the second rotation speed is 240-360 r / min, and the stirring time at the second rotation speed is 1-2 min; the third rotation speed is 180-240 r / min; the fourth rotation speed is 240-360 r / min, and the stirring time at the fourth rotation speed is 1.5-2.5 min; in step (3), the vibrating time of inserting the pneumatic vibrating rod into the mixed slurry is 1-2 min.

[0018] Beneficial effects:

[0019] The floor mudstone rapid hardening material of the present invention is mixed and stirred with the bauxite mudstone softened at the bottom of the coal mine roadway, and can quickly form a reinforcement layer with high strength, good toughness and water resistance, ensuring the normal passage of construction personnel and equipment; it can also improve the utilization rate of mudstone solid waste resources and reduce the use of natural aggregates such as sand and gravel. Specific embodiments

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art belong to the scope of protection of the present invention.

[0021] The present invention will be described in detail below with reference to the embodiments. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0022] Aiming at the problem that the bauxite floor mudstone is softened during the production process at present, the present invention provides a floor mudstone rapid hardening material to help realize the reinforcement of the bauxite softened mudstone and enhance the stability of the roadway floor.

[0023] The rapid hardening material for floor mudstone in the embodiments of the present invention, by weight, the rapid hardening material for floor mudstone includes the following components in parts by weight: 30-50 parts of sulfoaluminate cement (such as 30 parts, 35 parts, 40 parts, 45 parts or 50 parts), 20-30 parts of portland cement (such as 20 parts, 25 parts or 30 parts), 30-40 parts of gypsum (such as 30 parts, 35 parts or 40 parts), 1-3 parts of lime (such as 1 part, 2 parts or 3 parts), 0.5-2 parts of water reducing agent (such as 0.5 parts, 1.0 part or 2 parts), 1-4 parts of sacrificial agent (such as 1 part, 2 parts, 3 parts or 4 parts), 0.5-1 part of early strength agent (such as 0.5 part or 1 part), 0.1-0.5 part of retarder (such as 0.1 part, 0.2 part, 0.3 part, 0.4 part or 0.5 part), 1-3 parts of fiber (such as 1 part, 1.5 parts, 2 parts, 2.5 parts or 3 parts) and 40-60 parts of water (such as 40 parts, 45 parts, 50 parts, 55 parts or 60 parts); the components of the sacrificial agent include sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid and aluminate coupling agent. Among them, both gypsum and lime are used to adjust the type of hydration products generated by the hydration of sulfoaluminate cement and portland cement, as well as the speed of hydration rate; if the dosage of gypsum is too small, the product of sulfoaluminate cement is mainly monosulfate hydrated calcium aluminate (AFm), and the strength and water resistance are poor; as the dosage of gypsum increases, the product of sulfoaluminate cement is mainly tricalcium sulfoaluminate hydrate (AFt), and the strength is high; however, when the dosage of gypsum is too high, the hydration rate of portland cement will decrease; on the one hand, lime can provide Ca 2+ and OH - , and at the same time, the dissolution of lime in water will release heat, both of which can increase the cement hydration rate; when the dosage of lime is small, the cement hydration rate is relatively slow; when the dosage of lime is high, the hydration rate of the cement is too fast, on the one hand, it will cause insufficient mixing time, and on the other hand, the porosity of the overall structure of the hardening material will be relatively large, and the water resistance will decrease; if the dosage of the water reducing agent is too large, it will lead to a relatively slow setting and hardening rate of the whole, and the cost will increase significantly; if the dosage of the sacrificial agent is too small, the effect of the water reducing agent will be relatively limited, the viscosity when mixing with mudstone is large, and the construction difficulty is great; if the dosage of the sacrificial agent is too large, it will cause the setting and hardening time of the slurry to be prolonged.

[0024] In the rapid hardening material for the floor mudstone of the present invention, the gelling mix ratio of sulfoaluminate cement, Portland cement, gypsum and lime is an important factor for ensuring the early working strength and water resistance; the combined use of a water reducer and a sacrificial agent can improve the viscosity and fluidity of the mixture during the hardening of the aluminous floor mudstone, enhancing the workability; the effect of solely using a water reducer on improving the fluidity of the mixture is relatively limited, and a certain amount of sacrificial agent needs to be compounded to improve the water reducing efficiency of the water reducer and the wetting and affinity relationship between the rapid hardening material for the aluminous floor mudstone and the aluminous mudstone; early strength agents and retarders can adjust the setting and hardening time and early strength of the aluminous floor mudstone during reinforcement, ensuring a certain construction time; fibers dispersed in the reinforcement layer after the hardening of the aluminous floor mudstone can improve its flexural resistance and fatigue resistance, ensuring the passage of large construction equipment.

[0025] Among the sacrificial agents, sodium tripolyphosphate can adsorb on the surface of cement particles and disperse the cement particles through electrostatic repulsion, improving the fluidity of the mixed mud; cetyltrimethylammonium bromide can be oriented on the surface of cement particles and at the water interface to form an adsorption film to reduce the interfacial tension, making the cement more easily wetted by water, and at the same time can also adjust the charge distribution on the surface of cement particles, further enhancing the dispersion stability of cement particles; citric acid combined with calcium ions can delay the hydration rate of cement, ensuring the construction time during the reinforcement of the floor mudstone; the silane oxy groups of aluminate coupling agents hydrolyze to generate highly active silanol groups, which combine with the active sites on the surface of the aluminous mudstone, hindering the interference of the mudstone on the adsorption of the water reducer on the surface of cement particles.

[0026] Preferably, the water reducer is a naphthalene-based water reducer. Among them, the combined use of the naphthalene-based water reducer and the specific sacrificial agent of the present invention has the best effect on improving the fluidity. When using a polycarboxylate water reducer, during the process of reinforcing the mudstone, the polycarboxylate water reducer will be adsorbed on the surface of the mudstone in large amounts, and the sacrificial agent will reduce the adsorption amount of the polycarboxylate water reducer on the surface of the mudstone. Although it can improve the water reducing effect of the cement, the effect is relatively limited.

[0027] In a preferred embodiment of the rapid hardening material for floor mudstone of the present invention, by weight, the sacrificial agent includes: 20-25 parts of sodium tripolyphosphate (such as 20 parts, 21 parts, 22 parts, 23 parts, 24 parts or 25 parts), 0.25-0.5 parts of cetyltrimethylammonium bromide (such as 0.25 parts, 0.35 parts, 0.45 parts or 0.5 parts), 5-10 parts of citric acid (such as 5 parts, 6 parts, 7 parts, 8 parts, 9 parts or 10 parts) and 20-25 parts of aluminate coupling agent (such as 20 parts, 21 parts, 22 parts, 23 parts, 24 parts or 25 parts). Among them, if the dosage of sodium tripolyphosphate is too large, its adsorption on the surface of cement particles will hinder the normal hydration of cement, greatly prolonging the setting and hardening time; if the dosage of sodium tripolyphosphate is too small, its dispersing effect cannot be fully exerted, resulting in ineffective polymerization and hydration of cement particles, and the structure after setting and hardening is not dense enough, reducing the strength and water resistance; if the dosage of cetyltrimethylammonium bromide is too large, the phenomenon of foaming during mixing and stirring will increase, increasing the porosity after hardening; if the dosage of cetyltrimethylammonium bromide is too small, it is not enough to improve the compatibility between the cement composite cementitious system and aluminous mudstone, and the interfacial transition zone between the two is relatively poor; if the dosage of citric acid is too large, it will destroy the alkaline environment of the cement composite cementitious material, hinder the normal hydration of cement, and reduce the strength after setting and hardening; at the same time, the reaction between citric acid and aluminate coupling agent will affect the effect of aluminate coupling agent and the interfacial relationship between cement and aluminous mudstone; if the dosage of citric acid is too small, the setting and hardening rate of cement cannot be adjusted; if the dosage of aluminate coupling agent is too large, its self-aggregation will cause it to be unable to be evenly distributed at the interface between mudstone and cement material, and the defects formed by its self-aggregation will reduce the overall performance of the material; if the dosage of aluminate coupling agent is too small, it will affect the interfacial transition zone between mudstone and cement material not being dense enough, affecting the subsequent strength and water resistance.

[0028] In a preferred embodiment of the rapid hardening material for floor mudstone of the present invention, the sacrificial agent is obtained by mixing and grinding sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid and aluminate coupling agent; the particle size of the sacrificial agent < 20μm. Among them, if the particle size of the sacrificial agent is too large, it cannot be well dispersed in the mixing system during the mixing and stirring of aluminous mudstone and cement hardening material, making the overall fluidity worse; in addition, the increase in the particle size of the sacrificial agent will affect its hydration and dissolution rate, and sodium tripolyphosphate and citric acid cannot effectively adjust the hydration rate of cement, and the aluminate coupling agent cannot be evenly distributed at the interface between mudstone and hardening material and cannot effectively enhance the interfacial bonding force; moreover, the large-particle-size sacrificial agent will cause uneven mixing, resulting in defects in the internal structure of the hardened material.

[0029] Preferably, the sacrificial agent is obtained by mixing and grinding sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid and aluminate coupling agent in a planetary ball mill for 30 - 60 min (such as 30 min, 40 min, 50 min or 60 min).

[0030] In a preferred embodiment of the rapid hardening material for floor mudstone of the present invention, the sulfoaluminate cement is a 72.5 calcium sulfoaluminate binder; the Portland cement is a P.O 42.5 ordinary Portland cement.

[0031] In a preferred embodiment of the rapid hardening material for floor mudstone of the present invention, the gypsum is natural gypsum with a fineness of 600 mesh; the lime is quicklime with a fineness of 600 mesh. Among them, if the particle size of the gypsum is too large, it is difficult for the gypsum to disperse in the gelling system, and local accumulation is likely to occur, resulting in uneven mixing; at the same time, the gypsum is an important component for adjusting the hydration of sulfoaluminate cement and Portland cement. The increase in the particle size of the gypsum leads to a decrease in its dissolution rate, a decrease in the hydration rate of the sulfoaluminate cement, and a decrease in the early strength; if the particle size of the gypsum is too small, it will cause the gypsum to absorb too much water, thereby reducing the overall fluidity; the increase in the dissolution rate of the gypsum will also accelerate the setting and hardening process of the cement, resulting in insufficient mixing of the mudstone and the hardening material, affecting the construction quality; when the particle size of the lime is too large, on the one hand, it will also lead to uneven overall mixing; on the other hand, the lime provides an alkaline environment in the cement gelling system. The increase in its particle size reduces its dissolution rate, affects the hydration reaction of the Portland cement, and then delays the setting and hardening rate of the cement, reducing the early working strength; when the particle size of the lime is too small, its adsorption of a large amount of water will also affect the overall fluidity, and the increase in its dissolution rate leads to too strong an alkaline environment in the early stage, resulting in too fast a cement hardening rate, local overheating, and then affecting the construction time and quality.

[0032] In a preferred embodiment of the rapid hardening material for floor mudstone of the present invention, the water reducing agent is a naphthalene-based high-efficiency water reducing agent with a water reducing rate ≥ 20%; the early strength agent is aluminum sulfate with an industrial grade purity; the retarder is sodium gluconate with an industrial grade purity; the fiber is glass fiber with a length of 3 - 6 mm.

[0033] The present invention also proposes a preparation method for the rapid hardening material for floor mudstone. The preparation method of the rapid hardening material for floor mudstone in the embodiment of the present invention includes the following steps: Pour the sulfoaluminate cement, Portland cement, gypsum, lime, water reducing agent, sacrificial agent, early strength agent, retarder and fiber into a mixing barrel, add water in proportion, and mix evenly to obtain the rapid hardening material for floor mudstone.

[0034] In a preferred embodiment of the preparation method of the rapid hardening material for floor mudstone of the present invention, during mixing, a hand-held pneumatic stirrer is used to stir at a speed of 120 - 150 r / min (for example, 120 r / min, 130 r / min, 140 r / min, or 150 r / min) for 0.8 - 1.5 min (for example, 0.8 min, 1.0 min, 1.2 min, or 1.5 min), and then stir at a speed of 240 - 360 r / min (for example, 240 r / min, 270 r / min, 300 r / min, 330 r / min, or 360 r / min) for 0.8 - 1.5 min (for example, 0.8 min, 1.0 min, 1.2 min, or 1.5 min).

[0035] The present invention also provides a construction method for strengthening floor mudstone. The construction method for strengthening floor mudstone in the embodiments of the present invention includes the following steps: (1) Use a hand-held pneumatic stirrer to stir the softened mudstone on the floor at a first speed, and supplement water to keep the water content at 25% - 35% (for example, 25%, 27%, 29%, 31%, 33%, or 35%), and then stir at a second speed to mix the mudstone and water evenly to obtain a mud magma; (2) Use a hand-held pneumatic stirrer to stir the mud magma at a third speed, and continuously add the rapid hardening material for floor mudstone as described above, and then stir at a fourth speed to mix evenly to obtain a mixed slurry; (3) Insert a pneumatic vibrating rod into the slurry to vibrate it densely, and then level the surface with a spade.

[0036] In a preferred embodiment of the construction method for strengthening the floor mudstone of the present invention, in step (2), the mass ratio of the floor mudstone rapid hardening material to the mud magma is 1:(2 - 4) (for example, 1:2, 1:3 or 1:4); the first rotation speed is 120 - 150 r / min (for example, 120 r / min, 130 r / min, 140 r / min or 150 r / min), and the stirring time at the first rotation speed is 1.5 - 2.5 min (for example, 1.5 min, 1.8 min, 2.1 min, 2.3 min or 2.5 min); the second rotation speed is 240 - 360 r / min (for example, 240 r / min, 270 r / min, 300 r / min, 330 r / min or 360 r / min), and the stirring time at the second rotation speed is 1 - 2 min (for example, 1.0 min, 1.2 min, 1.5 min, 1.8 min or 2.0 min); the third rotation speed is 180 - 240 r / min (for example, 180 r / min, 200 r / min, 220 r / min or 240 r / min); the fourth rotation speed is 240 - 360 r / min (for example, 240 r / min, 270 r / min, 300 r / min, 330 r / min or 360 r / min), and the stirring time at the fourth rotation speed is 1.5 - 2.5 min (for example, 1.5 min, 1.8 min, 2.1 min, 2.3 min or 2.5 min); in step (3), the time for inserting the pneumatic vibrating rod into the mixed slurry and vibrating is 1 - 2 min (for example, 1.0 min, 1.2 min, 1.5 min, 1.8 min or 2.0 min).

[0037] The following specifically describes the floor mudstone rapid hardening material of the present invention, its preparation method and application through specific examples.

[0038] The sources of the main raw materials used in the following examples are as follows (unless otherwise specified, the raw materials used in the present invention can be purchased commercially): 72.5 calcium sulfoaluminate (CSA) binder, purchased from Tangshan Polar Bear Building Materials Co., Ltd.; PO 42.5 Ordinary Portland cement, purchased from Jiaozuo Qianye Cement Co., Ltd.; 600 mesh natural gypsum and lime, purchased from Jiaozuo Xieli Building Materials Co., Ltd., Henan Province; naphthalene-based high-efficiency water reducer, purchased from Hubei Aijin Chemical Co., Ltd.; sodium tripolyphosphate, purchased from Chongqing Chuandong Chemical (Group) Co., Ltd.; trimethyl hexadecyl ammonium bromide, purchased from Jinan Jinyu Chemical Co., Ltd.; citric acid, purchased from Suzhou Jiaxu Chemical Environmental Protection Technology Co., Ltd.; aluminate coupling agent, purchased from Shandong Shuntai New Materials Co., Ltd.; early strength agent, aluminum sulfate, purchased from Shandong Shantian Chemical Technology Co., Ltd.; retarder, sodium gluconate, purchased from Suzhou Xingang Chemical Co., Ltd.; fiber, 3 mm in length, purchased from Lingshou Taizhen Mineral Products Processing Plant; bauxite mudstone comes from Shanxi Coal Transportation and Marketing Group Huayang Coal Industry Co., Ltd., and its chemical composition is as follows:

[0039] Table 1 Chemical composition of bauxite mudstone

[0040]

[0041] Example 1

[0042] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight: 40 parts of sulphoaluminate cement, 20 parts of silicate cement, 40 parts of gypsum, 3 parts of lime, 0.5 parts of water reducer (naphthalene-based water reducer), 1 part of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 50 parts of water.

[0043] Among them, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 parts of trimethyl hexadecyl ammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0044] The preparation method of the floor mudstone rapid hardening material of the present embodiment comprises the following steps: pouring sulphoaluminate cement, silicate cement, gypsum, lime, water reducer, sacrificial agent, early strength agent, retarder and fiber uniformly mixed according to the material ratio into a mixing barrel, adding water in proportion, stirring at a low speed of 150 r / min for 1 minute with a handheld pneumatic stirrer, and then stirring at a high speed of 360 r / min for 1 minute to uniformly stir the raw materials, thereby obtaining the floor mudstone rapid hardening material of the present embodiment.

[0045] The construction method for reinforcing the bottom plate mudstone of this embodiment comprises the following steps:

[0046] (1) Use a hand-held pneumatic stirrer to stir the softened mudstone (bauxitic mudstone) on the bottom plate at a low speed of 150 r / min for 2 min, and appropriately supplement water to keep the water content of the mudstone magma at 30%. Then stir at a high speed of 360 r / min for 1 min to mix the mudstone and water evenly to obtain a mudstone magma;

[0047] (2) Use a hand-held pneumatic stirrer to stir the mudstone magma at a medium speed of 240 r / min, and continuously add the rapidly hardening material for the bottom plate mudstone of this embodiment (ready-to-use after mixing) while stirring evenly. Then stir at a high speed of 360 r / min for 2 min to mix the mudstone magma and the rapidly hardening material for the bottom plate mudstone of this embodiment evenly; wherein, the mass ratio of the rapidly hardening material for the bottom plate mudstone to the bottom plate mudstone is 1:2 (that is, the mass ratio of the rapidly hardening material for the bottom plate mudstone to the softened mudstone on the bottom plate before adding water in step (1) is 1:2).

[0048] (4) Insert the pneumatic vibrating rod into the slurry and vibrate it back and forth for 1 min to vibrate the mixed slurry densely, and then level the surface with a shovel.

[0049] Example 2

[0050] The rapidly hardening material for the bottom plate mudstone of this embodiment, by weight, includes: 50 parts of sulfoaluminate cement, 20 parts of portland cement, 30 parts of gypsum, 2 parts of lime, 0.5 part of water reducer, 1 part of sacrificial agent, 0.5 part of early strength agent, 0.1 part of retarder, 1 part of fiber, and 50 parts of water.

[0051] Among them, by mass, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of cetyltrimethylammonium bromide, 5 parts of citric acid, and 20 parts of aluminate coupling agent in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm).

[0052] The preparation method of the rapidly hardening material for the bottom plate mudstone of this embodiment and the construction method for strengthening the bottom plate mudstone are the same as those in Example 1 (the only difference from Example 1 is the different dosage ratios of the raw materials in the rapidly hardening material for the bottom plate mudstone used).

[0053] Example 3

[0054] The rapidly hardening material for the bottom plate mudstone of this embodiment, by weight, includes: 50 parts of sulfoaluminate cement, 20 parts of portland cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 part of early strength agent, 0.1 part of retarder, 1 part of fiber, and 50 parts of water.

[0055] Among them, by mass parts, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of trimethylhexadecylammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm).

[0056] The preparation method of the rapid hardening material for floor mudstone and the construction method for floor mudstone reinforcement in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is the dosage ratio of each raw material in the rapid hardening material for floor mudstone used).

[0057] Embodiment 4

[0058] The rapid hardening material for floor mudstone in this embodiment, by weight parts, includes: 50 parts of sulfoaluminate cement, 20 parts of portland cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducing agent, 4 parts of sacrificial agent, 1 part of early strength agent, 0.1 part of retarder, 1 part of fiber and 50 parts of water.

[0059] Among them, by mass parts, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of trimethylhexadecylammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm).

[0060] The preparation method of the rapid hardening material for floor mudstone and the construction method for floor mudstone reinforcement in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is the dosage ratio of each raw material in the rapid hardening material for floor mudstone used).

[0061] Embodiment 5

[0062] The rapid hardening material for floor mudstone in this embodiment, by weight parts, includes: 50 parts of sulfoaluminate cement, 20 parts of portland cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducing agent, 4 parts of sacrificial agent, 0.5 part of early strength agent, 0.5 part of retarder, 1 part of fiber and 50 parts of water.

[0063] Among them, by mass parts, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of trimethylhexadecylammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm).

[0064] The preparation method of the rapid hardening material for floor mudstone and the construction method for floor mudstone reinforcement in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is the dosage ratio of each raw material in the rapid hardening material for floor mudstone used).

[0065] Embodiment 6

[0066] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight, 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 3 parts of fiber and 50 parts of water.

[0067] Among them, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 parts of trimethyl hexadecyl ammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0068] The preparation method of the rapid hardening material for bottom plate mudstone and the construction method for reinforcing the bottom plate mudstone in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is that the proportion of each raw material used in the rapid hardening material for bottom plate mudstone is different).

[0069] Example 7

[0070] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight, 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 60 parts of water.

[0071] Among them, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 parts of trimethyl hexadecyl ammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0072] The preparation method of the rapid hardening material for bottom plate mudstone and the construction method for reinforcing the bottom plate mudstone in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is that the proportion of each raw material used in the rapid hardening material for bottom plate mudstone is different).

[0073] Example 8

[0074] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight, 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 50 parts of water.

[0075] Among them, the sacrificial agent is obtained by mixing and grinding 25 parts of sodium tripolyphosphate, 0.5 parts of trimethyl hexadecyl ammonium bromide, 5 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 30 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0076] The preparation method of the rapid hardening material for bottom plate mudstone and the construction method for reinforcing the bottom plate mudstone in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is that the proportion of each raw material used in the rapid hardening material for bottom plate mudstone is different).

[0077] Example 9

[0078] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight, 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 50 parts of water.

[0079] Among them, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 parts of trimethyl hexadecyl ammonium bromide, 10 parts of citric acid and 20 parts of aluminate coupling agent in a planetary ball mill for 60 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0080] The preparation method of the rapid hardening material for bottom plate mudstone and the construction method for reinforcing the bottom plate mudstone in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is that the proportion of each raw material used in the rapid hardening material for bottom plate mudstone is different).

[0081] Example 10

[0082] The rapid hardening material for the bottom plate mudstone of the present embodiment includes, by weight, 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 3 parts of lime, 2 parts of water reducer, 4 parts of sacrificial agent, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 50 parts of water.

[0083] Among them, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 parts of trimethyl hexadecyl ammonium bromide, 5 parts of citric acid and 25 parts of aluminate coupling agent in a planetary ball mill for 60 minutes (the particle size of the sacrificial agent is less than 20 μm).

[0084] The preparation method of the rapid hardening material for bottom plate mudstone and the construction method for reinforcing the bottom plate mudstone in this embodiment are the same as those in Embodiment 1 (the only difference from Embodiment 1 is that the proportion of each raw material used in the rapid hardening material for bottom plate mudstone is different).

[0085] Comparative Example 1

[0086] The bottom plate mudstone hardening material of this comparative example is different from that of Example 2 only in that, by weight, it includes: 50 parts of sulphoaluminate cement, 20 parts of silicate cement, 30 parts of gypsum, 2 parts of lime, 0.5 parts of water reducer, 0.5 parts of early strength agent, 0.1 parts of retarder, 1 part of fiber and 50 parts of water; the rest are consistent with Example 2.

[0087] Comparative Example 2

[0088] The difference between this comparative example and Example 2 is only that the construction method of the bottom plate mudstone reinforcement is different (the bottom plate mudstone hardening material used and its preparation method are the same as those in Example 2).

[0089] The construction method of the bottom plate mudstone reinforcement of this comparative example comprises the following steps:

[0090] (1) The mudstone softened on the bottom plate was stirred at a low speed of 120 r / min for 2 min by a handheld pneumatic stirrer, and water was appropriately added to keep the water content of the mudstone slurry at 30%, and then stirred at a high speed of 240 r / min for 1 min to mix the mudstone and water evenly to obtain mudstone slurry;

[0091] (2) The mudstone slurry is stirred at a medium speed of 180 r / min by a handheld pneumatic stirrer, and the bottom plate mudstone rapid hardening material of this embodiment (ready-to-use) is continuously added and stirred evenly, and then stirred at a high speed of 240 r / min for 2 minutes to evenly stir the mudstone slurry and the bottom plate mudstone rapid hardening material of this embodiment; wherein the mass ratio of the bottom plate mudstone rapid hardening material to the bottom plate mudstone is 1:2.

[0092] (4) Insert the pneumatic vibrator into the mud and vibrate it back and forth for 1 minute to compact the mixed slurry, and then use a shovel to smooth the surface.

[0093] Comparative Example 3

[0094] The difference between this comparative example and Example 2 is that in step (2) of the construction method for reinforcing the bottom plate mudstone of this comparative example, the mass ratio of the bottom plate mudstone rapid hardening material to the bottom plate mudstone is 1:4; the rest is consistent with Example 2.

[0095] Comparative Example 4

[0096] The bottom plate mudstone hardening material of this comparative example is different from that of Example 2 only in that, by weight, it includes 20 parts of sulphoaluminate cement; the rest is consistent with Example 2.

[0097] Comparative Example 5

[0098] The bottom plate mudstone hardening material of this comparative example is different from that of Example 2 only in that, by weight, it includes 70 parts of sulphoaluminate cement; the rest is consistent with Example 2.

[0099] Comparative Example 6

[0100] The bottom plate mudstone hardening material of this comparative example is different from that of Example 2 only in that, by weight, it includes 10 parts of silicate cement; the rest is consistent with Example 2.

[0101] Comparative Example 7

[0102] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, it includes: 40 parts of portland cement; the rest are the same as those in Example 2.

[0103] Comparative Example 8

[0104] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, it includes: 20 parts of gypsum; the rest are the same as those in Example 2.

[0105] Comparative Example 9

[0106] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, it includes: 50 parts of gypsum; the rest are the same as those in Example 2.

[0107] Comparative Example 10

[0108] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, it includes: 0 part of lime; the rest are the same as those in Example 2.

[0109] Comparative Example 11

[0110] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, it includes: 5 parts of lime; the rest are the same as those in Example 2.

[0111] Comparative Example 12

[0112] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: the particle sizes of both lime and gypsum are 1200 mesh; the rest are the same as those in Example 2.

[0113] Comparative Example 13

[0114] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: the water reducing agent is a polycarboxylate water reducing agent; the rest are the same as those in Example 2.

[0115] Comparative Example 14

[0116] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: the length of the fiber is 9 mm, and the rest are the same as those in Example 2.

[0117] Comparative Example 15

[0118] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: 80 parts of water, and the rest are the same as those in Example 2.

[0119] Comparative Example 16

[0120] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of cetyltrimethylammonium bromide, and 5 parts of citric acid in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm). The rest are the same as those in Example 2.

[0121] Comparative Example 17

[0122] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of cetyltrimethylammonium bromide, 5 parts of citric acid, and 60 parts of aluminate coupling agent in a planetary ball mill for 30 min (the particle size of the sacrificial agent is less than 20 μm). The rest are the same as those in Example 2.

[0123] Comparative Example 18

[0124] The difference between the floor mudstone hardening material of this comparative example and that of Example 2 is only that: by weight, the sacrificial agent is obtained by mixing and grinding 20 parts of sodium tripolyphosphate, 0.25 part of cetyltrimethylammonium bromide, 5 parts of citric acid, and 20 parts of aluminate coupling agent in a planetary ball mill for 5 min (the particle size of the sacrificial agent is greater than 80 μm). The rest are the same as those in Example 2.

[0125] Experimental Example

[0126] The fluidity, setting time, mechanical properties, and water resistance of the floor mudstone rapid hardening materials of the above examples and the mixed materials of the comparative examples were tested respectively (the tests were carried out after the construction of softening mudstone reinforcement); among them, the fluidity test referred to the "Standard Test Method for Fluidity of Cement Mortar" GB / T 2419-2005 and was tested through a truncated cone mold; the setting time test referred to the "Standard Test Method for Water Requirement of Normal Consistency, Setting Time and Soundness of Cement" GB / T 1346-2011 and was tested through a Vicat apparatus; the uniformly mixed materials were poured into molds of 70 mm×70 mm×70 mm and 40 mm×40 mm×160 mm, the surface was scraped flat, wrapped with plastic wrap, and cured in a curing room at a temperature of (20±2) °C and a relative humidity greater than 96% for a certain period of time and then demolded. After reaching the specified age, referring to the "Test Method for Strength of Cement Mortar (ISO Method)" GB / T 0506-2005, it was tested through a fully automatic cement flexural and compressive testing machine; among them, the water resistance test was to soak the specimens pre-cured for 1 day in water for 28 days, and calculate the ratio of the strength of the eroded specimens to that of the specimens cured under standard conditions. The specific results are shown in Table 1 below:

[0127] Table 1 Performance test results of floor mudstone rapid hardening materials

[0128]

[0129] Analysis of the above data shows that: the content of sulfoaluminate cement in Example 1 is 40%, compared with Example 2, the setting and hardening time is relatively long and the early strength is relatively low; in Example 3, the contents of water reducing agent and sacrificial agent increase, the fluidity of the mixture is improved, there is a little loss in the early strength of the mixture, but the later strength and water resistance are improved; Examples 4 and 5 illustrate that changing the contents of early strength agent and retarder can adjust the setting and hardening time and early strength of the mixture, and has little effect on the later strength; in Example 6, the fiber content increases, the fluidity of the mixture decreases, and the flexural strength is improved; in Example 7, the water consumption increases, the fluidity of the mixture is improved, the setting and hardening time is prolonged, and the strength and water resistance are reduced; in Example 8, the proportion of sodium tripolyphosphate and cetyltrimethylammonium bromide of the sacrificial agent increases, the charge distribution, electrostatic repulsion and surface tension on the surface of cement particles are improved, the dispersibility of cement particles is further improved, the fluidity and uniformity of the mixture are improved, and the strength and water resistance are improved; in Example 9, the proportion of citric acid of the sacrificial agent increases, and the adsorption of calcium ions by citric acid results in a prolonged setting and hardening time of the mixture and a relatively lower early strength; in Example 10, the proportion of aluminate coupling agent of the sacrificial agent increases, and the adsorption of the aluminate coupling agent on the surface of cement particles can improve the wetting and affinity relationship between cement and bauxite mudstone, improve the interfacial transition zone between the two, and improve the strength and water resistance of the mixture.

[0130] In Comparative Example 1, no sacrificial agent was added to the bauxite floor mudstone rapid hardening material. Comparing with Construction Example 2, it was found that the fluidity of the mixture decreased significantly, and the strength and water resistance of the mixture also decreased significantly. This is because adding the sacrificial agent to the bauxite floor mudstone rapid hardening material can adsorb on the surface of cement particles and improve the dispersibility of cement. The adsorption of the sacrificial agent on the surface of bauxite mudstone can reduce the influence of mudstone on the work of the water reducing agent and improve the water reducing efficiency of the water reducing agent. At the same time, the overall increase in the fluidity of the mixture can make the mixing of cement and bauxite mudstone more uniform, the strength of the interfacial transition zone between cement and bauxite mudstone better, and the strength and water resistance of the overall structure higher.

[0131] In Comparative Example 2, when the bauxite floor mudstone rapid hardening material was used to reinforce bauxite mudstone during construction, the decrease in the hand-held pneumatic stirring rate led to a decrease in the strength and water resistance of the mixture. This is because during low-speed stirring, the mixing uniformity of cement and bauxite mudstone is relatively reduced, the coating effect of cement on mudstone is relatively reduced, and the dispersion effect of cement inside the mixture does not reach the best, resulting in a decrease in the strength and water resistance after setting and hardening.

[0132] In Comparative Example 3, compared with Construction 2, the ratio of the aluminous floor mudstone rapid hardening material to reinforce mudstone increased from 1:2 to 1:4, resulting in an extended setting and hardening time of the mixture, as well as reduced fluidity, strength, and water resistance. This is mainly because the increase in the proportion of mudstone requires more water reducers and sacrificial agents in the mixture to improve the wettability and dispersibility between cement and mudstone to ensure the original fluidity of the mudstone. The decrease in the fluidity of the mixture also leads to a decrease in the degree of uniform dispersion of cement in the mixture. Moreover, the decrease in the cement content leads to a decrease in the strength of the mixture on the one hand and a decrease in the degree of cement coating on the mudstone on the other hand, resulting in a reduction in the overall water resistance.

[0133] In Comparative Example 4, the content of sulfoaluminate cement in the aluminous floor mudstone rapid hardening material was reduced to 20 parts, resulting in an extended setting and hardening time of the mixture, as well as reduced strength and water resistance. This is because the hydration rate of sulfoaluminate cement is fast, which can rapidly generate a large amount of products such as AFt, improving the early strength. At the same time, in an alkaline environment, sulfoaluminate cement can react with some active substances in aluminous mudstone to improve the overall strength.

[0134] In Comparative Example 5, the content of sulfoaluminate cement in the aluminous floor mudstone rapid hardening material was increased to 70 parts, resulting in an extended setting and hardening time of the mixture, as well as reduced strength and water resistance. This is because the hydration of sulfoaluminate requires the consumption of a certain amount of gypsum and lime, and the increase in the amount of sulfoaluminate cement leads to a disorder in the overall reaction with Portland cement, gypsum, and water-cement ratio, affecting the hydration reaction process and thus the overall strength. At the same time, the hydration heat release of sulfoaluminate cement is fast and the heat release amount is large. The increase in its dosage leads to a large temperature difference between the inside and outside of the mixture, resulting in the formation of microcracks of different sizes inside, thus affecting its strength and water resistance.

[0135] In Comparative Example 6, the content of Portland cement in the aluminous floor mudstone rapid hardening material was reduced to 10 parts, resulting in an extended setting and hardening time of the mixture and a reduction in the overall strength. This is because tricalcium silicate in Portland cement can react quickly with sulfoaluminate cement to form calcium aluminofeldspar, improving the early strength. At the same time, calcium hydroxide generated by the hydration of Portland cement can accelerate the hydration rate of sulfoaluminate cement. The reduction in the content of Portland cement leads to a weakening of the synergistic reaction between cementitious materials, affecting the overall strength development.

[0136] In Comparative Example 7, the content of Portland cement in the aluminous floor mudstone rapid hardening material was increased to 40 parts, resulting in an extended setting and hardening time of the mixture and a serious reduction in the early strength. This is because compared with sulfoaluminate cement, the hydration rate of Portland cement itself is relatively slow. Since the porosity of the hydration products of Portland cement is relatively large, and its increase affects the synergistic reaction process with sulfoaluminate cement, gypsum, and lime, the later strength is also reduced.

[0137] In Comparative Example 8, the gypsum content in the aluminous floor mudstone rapid hardening material was reduced to 20 parts, resulting in an extended setting and hardening time of the mixture, as well as reduced strength and water resistance. This is because the decrease in gypsum content led to a reduction in the formation of AFt during the hydration of sulfoaluminate cement, slowing down the setting and hardening process and reducing the early strength.

[0138] In Comparative Example 9, the gypsum content in the aluminous floor mudstone rapid hardening material was increased to 50 parts, resulting in an extended setting and hardening time of the mixture, as well as reduced strength and water resistance. This is because excessive gypsum would cause a large amount of AFt to be formed during the hydration of sulfoaluminate cement, making the internal structure of the material loose and increasing the porosity. At the same time, the excessive gypsum and calcium hydroxide formed during the hydration of portland cement would lead to an increase in the secondary hydration reaction, and the formed secondary AFt and calcium sulfate, etc. would damage the original structure, further reducing the overall strength and water resistance.

[0139] In Comparative Examples 4, 6, and 8, the fluidity of the mixture increased because the proportion of the cementitious material decreased and the proportion of the admixture increased. Similarly, in Comparative Examples 5, 7, and 9, the fluidity of the mixture decreased because the proportion of the admixture decreased.

[0140] In Comparative Example 10, the lime content in the aluminous floor mudstone rapid hardening material was reduced to 0 part, resulting in better fluidity, an extended setting and hardening time, and reduced strength and water resistance of the mixture. This is because lime in the mixture would absorb some moisture and react to form calcium hydroxide, promoting the formation of hydration products such as AFt and C-S-H gel, thereby shortening the setting and hardening time and improving the strength, density, and water resistance of the overall structure.

[0141] In Comparative Example 11, the lime content in the aluminous floor mudstone rapid hardening material was increased to 5 parts, resulting in changes in the fluidity of the mixture, a shortened setting and hardening time, and a decrease in strength and water resistance. This is because after the lime dosage increased, the absorbed moisture increased and the alkaline environment improved, thereby leading to an accelerated early hydration rate of the cement. However, due to the excessive lime, the rate of formation of AFt from sulfoaluminate cement increased, and the growth of AFt was uneven, forming a relatively loose structure. At the same time, the excessive lime would consume a certain amount of sulfate ions, affecting the degree of hydration of the cement. Therefore, the overall strength and water resistance of the material decreased relatively.

[0142] In Comparative Example 12, the particle size of lime and gypsum in the aluminous floor mudstone rapid hardening material was increased from 600 mesh to 1200 mesh, resulting in a decrease in the fluidity of the mixture, an acceleration of the setting and hardening time, and a decrease in strength and water resistance. This is mainly because finer lime and gypsum require more water during stirring, resulting in a decrease in the free water content in the mixture, and thus a decrease in fluidity. Due to the poor overall fluidity of the mixture and the relatively fast setting and hardening rate, the degree of uniformity between the aluminous floor mudstone rapid hardening material and the aluminous mudstone is relatively low, thereby leading to a decrease in its strength and water resistance.

[0143] In Comparative Example 13, a polycarboxylate water reducer was used in the aluminous floor mudstone rapid hardening material, resulting in poor fluidity, strength and water resistance of the mixture. This is because the naphthalene-based water reducer molecules have a linear structure and are adsorbed relatively evenly on the surfaces of cement and mudstone particles, which can effectively disperse the particles and improve fluidity. The molecular structure of the polycarboxylate water reducer is comb-shaped, and its adsorption on the surfaces of cement and mudstone particles is an important prerequisite for its water-reducing property. Due to the extremely high specific surface area of a large amount of clay minerals in the mudstone, a large number of polycarboxylate water reducer molecules are preferentially adsorbed, resulting in a decrease in the adsorption amount on the cement particle surface and a decrease in the dispersion effect on the particles, poor fluidity of the mixture, and further a decrease in the uniformity of the reinforcing material and the mudstone in the mixture, as well as a decrease in strength and water resistance.

[0144] In Comparative Example 14, the length of the fiber in the aluminous floor mudstone rapid hardening material was increased from 3 mm to 9 mm, resulting in a decrease in the fluidity, strength and water resistance of the mixture. This is mainly because the fiber length is too long, increasing the difficulty of stirring the aluminous mudstone and the rapid hardening material, and the fiber is mainly concentrated inside the hardening material and is difficult to be evenly dispersed in the mudstone, thereby leading to a decrease in strength and water resistance.

[0145] In Comparative Example 15, the water content in the aluminous floor mudstone rapid hardening material was increased from 50 parts to 80 parts, resulting in an extension of the setting and hardening time of the mixture, and a decrease in strength and water resistance. This is mainly because excessive water will increase the distance between cement particles, reducing the probability of cement particles contacting water and undergoing hydration reactions, resulting in a slower hydration reaction rate. Excessive water forms a large number of pores inside the cement stone, reducing the density of the cement stone. When subjected to external forces, stress concentration occurs around the pores, easily causing crack propagation, thus reducing the strength of the material. At the same time, these pores provide a convenient channel for the intrusion of water. Water is more likely to enter the interior of the cement stone and dissolve some soluble substances therein, such as calcium hydroxide, thereby destroying the structure of the cement stone and reducing its water resistance.

[0146] In Comparative Example 16, the aluminate coupling agent was not added to the sacrificial agent, resulting in a decrease in the strength and water resistance of the mixture. This is mainly because the aluminate coupling agent can improve the interfacial properties of the material and enhance the interfacial bonding effect between the bauxitic mudstone and the rapid-hardening material. The absence of the aluminate coupling agent leads to insufficient interfacial bonding between the mudstone and the hardening material, and cracks are likely to occur at the interface when the material is stressed, thereby affecting the strength and water resistance of the material.

[0147] In Comparative Example 17, the amount of the aluminate coupling agent in the sacrificial agent was increased to 60 parts, which also led to a decrease in the strength and water resistance of the mixture. This is because when the dosage of the aluminate coupling agent is too large, the coupling agent will agglomerate itself and cannot be evenly distributed at the interface between the mudstone and the hardening material, resulting in a relatively reduced improvement effect on the interfacial bonding. Moreover, the defects formed by the agglomeration will also affect the overall strength and water resistance of the material.

[0148] In Comparative Example 18, the mixing and grinding time of the sacrificial agent in the planetary ball mill was reduced, and the particle size of the sacrificial agent increased, resulting in a decrease in the fluidity, strength, and water resistance of the mixture. On the one hand, it is because the sacrificial agent with a larger particle size is difficult to be evenly dispersed in the mixture, the protection of the water-reducing effect of the water reducer is reduced, and the decrease in the fluidity of the mixture leads to a decrease in the uniformity of the mixture. On the other hand, it is because the release rate of each component in the sacrificial agent is reduced, and sodium tripolyphosphate, citric acid, cetyltrimethylammonium bromide, and the aluminate coupling agent cannot be released and function in time, resulting in a relatively reduced effect on the cement hydration process and the interfacial modification effect.

[0149] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, various changes and modifications can be made to the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A rapid hardening material for floor mudstone, characterized in that, In parts by weight, the rapid hardening material for floor mudstone comprises the following components in parts by weight: 30-50 parts of sulfoaluminate cement, 20-30 parts of portland cement, 30-40 parts of gypsum, 1-3 parts of lime, 0.5-2 parts of water reducing agent, 1-4 parts of sacrificial agent, 0.5-1 part of early strength agent, 0.1-0.5 part of retarder, 1-3 parts of fiber and 40-60 parts of water; The sacrificial agent includes sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid and aluminate coupling agent.

2. The rapid hardening material for floor mudstone according to claim 1, characterized in that, In parts by weight, the sacrificial agent includes: 20-25 parts of sodium tripolyphosphate, 0.25-0.5 part of cetyltrimethylammonium bromide, 5-10 parts of citric acid and 20-25 parts of aluminate coupling agent.

3. The rapid hardening material for floor mudstone according to claim 1, characterized in that, The sacrificial agent is obtained by mixing and grinding sodium tripolyphosphate, cetyltrimethylammonium bromide, citric acid and aluminate coupling agent; The particle size of the sacrificial agent < 20μm.

4. The quick-hardening material for floor mudstone according to claim 1, characterized in that, The sulfoaluminate cement is 72.5 calcium sulfoaluminate binder; The portland cement is P.O 42.5 ordinary portland cement.

5. The quick-hardening material for floor mudstone according to claim 1, wherein The gypsum is natural gypsum with a fineness of 600 mesh; The lime is quicklime with a fineness of 600 mesh.

6. The rapid hardening material for floor mudstone according to claim 1, characterized in that, The water reducing agent is a naphthalene series water reducing agent with a water reducing rate ≥ 20%; The early strength agent is aluminum sulfate with an industrial grade purity; The retarder is sodium gluconate with an industrial grade purity; The fiber is glass fiber with a length of 3-6mm.

7. The preparation method of the floor mudstone rapid hardening material according to any one of claims 1-6, characterized in that, It includes the following steps: Pour the sulfoaluminate cement, portland cement, gypsum, lime, water reducing agent, sacrificial agent, early strength agent, retarder and fiber into a mixing barrel, add water in proportion, and mix evenly to obtain the rapid hardening material for floor mudstone.

8. The preparation method of the floor mudstone rapid hardening material according to claim 7, characterized in that, During mixing, stir with a hand-held pneumatic stirrer at a speed of 120-150 r / min for 0.8-1.5 min, and then stir at a speed of 240-360 r / min for 0.8-1.5 min.

9. A construction method for reinforcing floor mudstone, characterized in that It includes the following steps: (1) Stir the softened mudstone of the floor with a hand-held pneumatic stirrer at a first speed, and supplement water to keep the water content at 25%-35%, then stir at a second speed to mix the mudstone and water evenly to obtain a mudstone slurry; (2) Stir the mudstone slurry with a hand-held pneumatic stirrer at a third speed, and continuously add the rapid hardening material for floor mudstone as described in any one of claims 1-6, then stir at a fourth speed and mix evenly to obtain a mixed slurry; (3) Insert a pneumatic vibrating rod into the mixed slurry to vibrate it densely, and then level the surface with a shovel.

10. The construction method for reinforcing floor mudstone as described in claim 9, characterized in that, In step (2), the mass ratio of the rapid hardening material for floor mudstone to the mudstone slurry is 1:(2-4); The first speed is 120-150 r / min, and the stirring time at the first speed is 1.5-2.5 min; The second speed is 240-360 r / min, and the stirring time at the second speed is 1-2 min; The third speed is 180-240 r / min; The fourth speed is 240-360 r / min, and the stirring time at the fourth speed is 1.5-2.5 min; In step (3), the time for inserting the pneumatic vibrator into the mixing slurry and vibrating is 1 - 2 minutes.

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