Hard rock tunneling slag resource utilization improvement process

Abstract

The application discloses a hard rock tunneling slag resource utilization improvement process and belongs to the technical field of slag resource utilization, and comprises the following steps: mixing hard rock tunneling slag with a dehydrating agent, uniformly stirring, covering and stewing the mixture for 8-12 hours, crushing and mixing, and obtaining pretreated slag; mixing the pretreated slag, a powder soil solidifying agent and reinforcing fillers, stirring and mixing at a speed of 500-600 r / min for 30-40 minutes, crushing and mixing, and obtaining resource utilization improved slag. Modified cellulose nanocrystals, modified graphene oxide, green acid modified chitosan and hydroxyethyl cellulose in the reinforcing fillers are mixed to form a three-dimensional network structure combined by hydrogen bonds, play a role in stress transfer, enhance the mechanical properties of the slag-based concrete, and the green acid modified chitosan and the hydroxyethyl cellulose can be adsorbed to the surface of the slag as the skeleton structure of the slag, further enhance the compactness of the slag and improve the mechanical properties.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of slag resource utilization, in particular to a hard rock tunneling slag resource utilization improvement process. BACKGROUND

[0002] Engineering slag is mainly derived from tunnel traffic, road construction, site leveling and other engineering, which has the characteristics of huge stock, wide source, complex composition and large difference. The huge amount of engineering slag not only pollutes the environment, but also wastes land resources, and has safety hazards. Therefore, improving the engineering waste slag and using it as roadbed filling material to realize resource utilization is an important way to promote the renewable development of the highway field. The current general method for improving engineering slag is to directly discharge it for natural drying, but the treatment efficiency is low and it is easy to cause secondary pollution. The improvement methods of engineering slag mainly include physical improvement, chemical improvement and biological improvement.

[0003] The use of dehydrating agent and slag curing agent to treat engineering slag can reduce the water content of engineering slag, and has good fluidity and suitable consistency, and is widely used in building materials, such as brick making and road construction. However, the mechanical properties of building materials prepared from engineering slag are poor, which affects the application of slag in building materials, and the engineering slag has a large number of pores and poor compactness. SUMMARY

[0004] The purpose of the present application is to provide a hard rock tunneling slag resource utilization improvement process: calcium carbonate particles are formed on the surface of polydopamine modified cellulose nanowhiskers, the formed nano calcium carbonate particles can penetrate into the pores of the slag, improve the compactness of the slag, and enhance the mechanical properties of the slag; nano alumina is formed on the surface of graphene oxide, providing a large number of rough surfaces, increasing the contact area with the slag, so that the graphene oxide loaded with nano alumina is closely combined with the slag, improving the mechanical properties of the slag; octamethylcyclotetrasiloxane is grafted on the surface of graphene oxide loaded with nano alumina, octamethylcyclotetrasiloxane can react with organic silicon in the slag, thereby enhancing the bonding force between the modified graphene oxide and the slag, further enhancing the compactness of the slag, and improving the mechanical properties of the slag; modified cellulose nanowhiskers, modified graphene oxide, green acid modified chitosan and hydroxyethyl cellulose are mixed to form a three-dimensional network structure combined by hydrogen bonds, which plays a role in transferring stress, further enhancing the mechanical properties of the slag-based concrete.

[0005] The technical problems solved by the present application are: the engineering slag soil is treated by a dehydrating agent and a slag soil curing agent, the water content of the engineering slag soil can be reduced, the engineering slag soil has good flow plasticity and suitable consistency, and is widely used in building materials, such as brick making and road construction, but the mechanical properties of the building materials prepared from the engineering slag soil are poor, which affects the application of the slag soil in building materials, and the engineering slag soil has a large number of pores and poor compactness.

[0006] To achieve the above object, the present application provides the following technical scheme:

[0007] A hard rock tunneling slag soil resource improvement process method, comprising the following steps:

[0008] S1. The hard rock tunneling slag soil is mixed with a dehydrating agent, stirred uniformly, covered and stewed for 8-12h, crushed, stirred and mixed to obtain pretreated slag soil;

[0009] S2. The pretreated slag soil, the powder soil curing agent and the reinforcing filler are mixed, stirred and mixed at a speed of 500-600r / min for 30-40min, crushed, stirred and mixed to obtain resource improved slag soil.

[0010] The reinforcing filler is obtained by mixing and reacting modified cellulose nanowhiskers, modified graphene oxide, green acid modified chitosan and hydroxyethyl cellulose;

[0011] The modified cellulose nanowhiskers are obtained by modifying cellulose nanowhiskers with polydopamine and then depositing calcium carbonate particles in situ;

[0012] The modified graphene oxide is obtained by mixing graphene oxide, aluminum nitrate solution and urea, then reacting after hydrothermal reaction, and then reacting with octamethylcyclotetrasiloxane.

[0013] Further, the mass ratio of the hard rock tunneling slag soil to the dehydrating agent is (80-100):(5-7).

[0014] Further, the dehydrating agent is quicklime.

[0015] Further, the mass ratio of the pretreated slag soil, the powder soil curing agent and the reinforcing filler is (80-100):(4-6):(8-10).

[0016] Further, the powder soil curing agent is obtained by mixing methyl sodium silicate, sodium alginate, sodium dodecylbenzenesulfonate, sodium chloride, lithium hydroxide and polycarboxylic acid superplasticizer according to a mass ratio of (3-5):(0.6-1):(1-1.5):(0.8-1.2):(0.1-0.3):(0.2-0.4).

[0017] Further, the reinforcing filler is prepared by the following steps:

[0018] A1. Add cellulose nanowhiskers into Tris-HCl buffer solution, stir until uniform, add dopamine, stir for 3-5h, filter, wash, dry, to obtain polydopamine modified cellulose nanowhiskers;

[0019] A2. Add calcium chloride into deionized water, stir until completely dissolved, add polydopamine modified cellulose nanowhiskers, stir until uniform, add ammonia to adjust pH to 7-9, place in a reaction kettle, pass in carbon dioxide and air, after the reaction is complete, collect the solid by filtration, dry the solid, to obtain modified cellulose nanowhiskers;

[0020] A3. Add graphene oxide into aluminum nitrate solution, stir until uniform, add urea, place in a high-pressure kettle at 140-160℃, perform hydrothermal reaction for 5-8h, cool to room temperature, collect the gelatinous material by filtration, calcine at 500-600℃ for 1-3h, to obtain graphene oxide loaded with nano-alumina;

[0021] A4. Add graphene oxide loaded with nano-alumina into deionized water, stir until uniform, add sulfuric acid and octamethylcyclotetrasiloxane, heat to 55-65℃, stir for 2-4h, cool to room temperature, filter, wash, dry, to obtain modified graphene oxide;

[0022] A5. Add nanocellulose and chlorogenic acid modified chitosan into deionized water, stir until uniform, add sodium hydroxide, stir at 50-60℃ for 10-15min, add modified graphene oxide and modified cellulose nanowhiskers, continue to stir for 10-20min, to obtain a reinforcing filler.

[0023] Further, during the reaction of step A1, dopamine can self-polymerize on the surface of cellulose nanowhiskers in the Tris-HCl buffer solution to form polydopamine, forming polydopamine modified cellulose nanowhiskers, which makes the cellulose nanowhiskers have good adhesion, and is conducive to the formation of calcium carbonate particles on the surface of the cellulose nanowhiskers.

[0024] Further, during the reaction of step A2, the phenolic hydroxyl groups contained on the surface of the polydopamine modified cellulose nanowhiskers can combine with the calcium ions in the calcium chloride, causing the calcium ions to deposit on the surface of the polydopamine modified cellulose nanowhiskers. After passing in carbon dioxide and air, a carbonization reaction is performed, which can form calcium carbonate crystals on the surface of the polydopamine modified cellulose nanowhiskers. As the reaction proceeds, the NH4 + can combine with the hydroxyl groups on the surface of the calcium carbonate crystals, promoting the aggregation and growth of the calcium carbonate crystals, and enabling calcium carbonate particles to be formed on the surface of the polydopamine modified cellulose nanowhiskers, to obtain modified cellulose nanowhiskers.

[0025] Further, in the reaction process of step A3, the oxygen-containing functional groups contained on the surface of graphene oxide can combine with aluminum ions in the aluminum nitrate solution, so that the aluminum hydroxide generated in the reaction process is deposited on the surface of graphene oxide. After hydrothermal treatment, the aluminum hydroxide is decomposed by heat to form aluminum oxide crystals. With the progress of the reaction, the aluminum oxide crystals grow to form nano-aluminum oxide on the surface of graphene oxide, and the graphene oxide loaded with nano-aluminum oxide is obtained.

[0026] Further, in the reaction process of step A4, octamethylcyclotetrasiloxane is ring-opening polymerized under acid catalysis, and the terminal hydroxyl groups of the polysiloxane chain react with the hydroxyl groups on the surface of the graphene oxide loaded with nano-aluminum oxide, so that octamethylcyclotetrasiloxane is grafted on the surface of the graphene oxide loaded with nano-aluminum oxide, and the modified graphene oxide is obtained.

[0027] Further, in the reaction process of step A5, the chlorogenic acid modified chitosan and the hydroxyethyl cellulose are combined by hydrogen bonds to form a cross-linked network structure, and the modified cellulose nanocrystal whiskers and the modified graphene oxide are embedded in the cross-linked network structure to form a three-dimensional network structure combined by hydrogen bonds, and the reinforcing filler is obtained.

[0028] Further, in step A1, the dosage ratio of cellulose nanocrystal whiskers, Tris-HCl buffer solution and dopamine is (1-2) g:(50-60) mL:(0.4-0.6) g.

[0029] Further, in step A2, the dosage ratio of calcium chloride, deionized water and polydopamine modified cellulose nanocrystal whiskers is (7-9) g:(75-85) mL:(3-5) g.

[0030] Further, in step A2, the volume ratio of carbon dioxide and air is (1-3):(5-7).

[0031] Further, in step A3, the dosage ratio of graphene oxide, aluminum nitrate solution and urea is (4-5) g:(45-55) mL:(4-6) g.

[0032] Further, in step A4, the dosage ratio of graphene oxide loaded with nano-aluminum oxide, deionized water, sulfuric acid and octamethylcyclotetrasiloxane is (4-6) g:(20-30) mL:(4-6) mL:(1-1.4) g.

[0033] Further, in step A5, the mass ratio of modified cellulose nanocrystal whiskers, modified graphene oxide, chlorogenic acid modified chitosan and hydroxyethyl cellulose is (2-4):(3-5):(8-10):(10-12).

[0034] Further, the concentration of the aluminum nitrate solution is 0.2-0.4 mol / L.

[0035] Further, the hydrothermal reaction temperature is 140-160 DEG C, and the hydrothermal reaction time is 5-8h.

[0036] Further, the graphene oxide particle size is 0.2-1 mu m.

[0037] Further, the cellulose nanowhisker is prepared by the following steps:

[0038] The microcrystalline cellulose is added into the sulfuric acid solution, stirred uniformly, placed in 35-45 DEG C, stirred and reacted for 1-3h, diluted by adding deionized water to end the reaction, separated, and the collected nanowhisker is dispersed in deionized water, treated by dialysis, and freeze-dried to obtain the cellulose nanowhisker.

[0039] Further, the microcrystalline cellulose and the sulfuric acid solution are used in a ratio of (5-7)g:(80-100)mL.

[0040] Further, the chlorogenic acid modified chitosan is prepared by the following steps:

[0041] The chitosan is added into the acetic acid solution, stirred uniformly to obtain a chitosan solution, the chlorogenic acid, N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl) carbonyl diimide hydrochloride are added into ethanol, stirred and mixed, then added into the chitosan solution, stirred in an ice water bath until the reaction is completed, centrifuged to collect the supernatant, and the supernatant is freeze-dried to obtain the chlorogenic acid modified chitosan.

[0042] Further, in the above reaction process, the chlorogenic acid reacts with the chitosan, and then the chlorogenic acid is grafted on the chitosan to obtain the chlorogenic acid modified chitosan.

[0043] Further, the chitosan, the acetic acid solution, the chlorogenic acid, the N-hydroxysuccinimide, the 1-ethyl-(3-dimethylaminopropyl) carbonyl diimide hydrochloride and the ethanol are used in a ratio of (1-3)g:(45-55)mL:(0.4-0.6)g:(0.1-0.3)g:(0.2-0.24)g:(18-22)mL.

[0044] Further, compared with the prior art, the present application has the following beneficial effects:

[0045] (1) In the technical scheme of the present application, the polydopamine modified cellulose nanocrystal whisker makes the cellulose nanocrystal whisker have good adhesion, which is conducive to the formation of calcium carbonate particles on the surface of the cellulose nanocrystal whisker, and enhances the mechanical properties of the slag soil based concrete; the formation of calcium carbonate particles on the surface of the polydopamine modified cellulose nanocrystal whisker can penetrate into the pores of the slag soil on the one hand, improve the compactness of the slag soil, and enhance the mechanical properties of the slag soil; on the other hand, the cellulose nanocrystal whisker can be filled in the micropores and cracks of the slag soil, as a bridging structure, tightly connecting the slag soil together, significantly improving the strength and durability of the slag soil, in addition, the excellent aspect ratio of the cellulose nanocrystal whisker, which is randomly distributed in the slag soil, improves the impact resistance of the slag soil.

[0046] (2) In the technical scheme of the present application, the formation of nano-alumina on the surface of graphene oxide provides a large number of rough surfaces, increases the contact area with the slag soil, makes the graphene oxide loaded with nano-alumina tightly combined with the slag soil, and improves the mechanical properties of the slag soil; on the other hand, the formation of nano-alumina on the surface of graphene oxide as a nano material can fill the pores, improve the compactness of the slag soil, and is conducive to the transportation of the slag soil, and the formed slag soil based concrete has high mechanical properties; octamethylcyclotetrasiloxane is grafted on the surface of graphene oxide loaded with nano-alumina, which can react with organic silicon in the slag soil, thereby enhancing the bonding force between the modified graphene oxide and the slag soil, further enhancing the compactness of the slag soil, and improving the mechanical properties of the slag soil.

[0047] (3) In the technical scheme of the present application, chlorogenic acid is grafted on chitosan, and then mixed with modified cellulose nanocrystal whisker, modified graphene oxide and hydroxyethyl cellulose to form a three-dimensional network structure combined by hydrogen bond, which plays a role in transferring stress, further enhances the mechanical properties of the slag soil based concrete, and the chlorogenic acid modified chitosan and hydroxyethyl cellulose as the skeleton structure of the slag soil can be adsorbed to the surface of the slag soil, further enhancing the compactness of the slag soil and improving the mechanical properties. DETAILED DESCRIPTION

[0048] The technical scheme in the embodiments of the present application is described clearly and completely, obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor belong to the scope of protection of the present application.

[0049] The raw materials used in the embodiments of the present application are as follows, and the reagents used are all analytical grade.

[0050] The hard rock tunneling slag soil is selected from the slag soil generated by TBM (full-face rock tunneling machine) tunneling.

[0051] Hard rock excavation muck performance indicators are shown in the following table:

[0052] Table 1

[0053]

[0054] Quicklime was purchased from Jiangsu Yangzhou Yongshun Purification Materials Co., Ltd.

[0055] The graphene oxide particle size was 0.5 pm.

[0056] Microcrystalline cellulose was purchased from Shanghai Maikelin Biochemical Technology Co., Ltd.

[0057] The cellulose nanowhisker was prepared by the following steps:

[0058] 6 g of microcrystalline cellulose was added to 90 mL of a 64% by mass sulfuric acid solution, stirred uniformly, and placed in a 40°C water bath for stirring reaction for 2 h. 100 mL of deionized water was added to dilute and end the reaction. After separation, the collected nanowhisker was dispersed in 100 mL of deionized water, treated by dialysis, and freeze-dried at -20°C for 1 h to obtain the cellulose nanowhisker.

[0059] The chlorogenic acid modified chitosan was prepared by the following steps:

[0060] 2 g of chitosan was added to 50 mL of a 2% by mass acetic acid solution, stirred uniformly to obtain a chitosan solution. 0.5 g of chlorogenic acid, 0.2 g of N-hydroxysuccinimide, and 0.22 g of 1-ethyl-(3-dimethylaminopropyl) carbonyl diimide hydrochloride were added to 20 mL of ethanol, stirred and mixed for 2 h, and then added to the chitosan solution. The mixture was stirred in an ice water bath for reaction for 40 min, centrifuged at 10,000 r / min for 20 min, and the supernatant was collected. The supernatant was freeze-dried at -20°C for 20 min to obtain the chlorogenic acid modified chitosan.

[0061] The reinforcing filler of Example 1 was prepared by the following steps:

[0062] A1. 1.5 g of cellulose nanowhisker was added to 55 mL of Tris-HCl buffer solution with a pH of 8.5, stirred uniformly, 0.5 g of dopamine was added, and stirred for 4 h. After filtration, the product was washed with deionized water for 3 times, and dried in a 70°C oven for 10 min to obtain the polydopamine modified cellulose nanowhisker.

[0063] A2. 8 g of calcium chloride was added to 80 mL of deionized water, stirred until completely dissolved, 4 g of polydopamine modified cellulose nanowhiskers was added, stirred for 10 min, 30% ammonia water was added to adjust the pH to 8, placed in a reaction kettle, 2 mL of carbon dioxide and 6 mL of air were introduced at a rate of 2.5 L / min, reacted at 30°C for 2 h, the solid was collected by filtration, and the solid was dried in an oven at 105°C for 20 min to obtain modified cellulose nanowhiskers;

[0064] A3. 4.5 g of graphene oxide was added to 50 mL of 0.3 mol / L aluminum nitrate solution, stirred uniformly, 5 g of urea was added, placed in a 150°C autoclave, and hydrothermal reaction was carried out for 6 h, cooled to room temperature, and the gelatinous material was collected by filtration and calcined at 550°C for 2 h to obtain graphene oxide loaded with nano-alumina;

[0065] A4. 5 g of graphene oxide loaded with nano-alumina was added to 25 mL of deionized water, stirred uniformly, 5 mL of 3% sulfuric acid and 1.2 g of octamethylcyclotetrasiloxane were added, the temperature was raised to 60°C, and the reaction was stirred for 3 h, cooled to room temperature, filtered, washed with deionized water 3 times, and dried in an oven at 70°C for 10 min to obtain modified graphene oxide;

[0066] A5. 11 g of nanocellulose and 9 g of chlorogenic acid modified chitosan were added to 20 mL of deionized water, stirred uniformly, 7 g of sodium hydroxide was added, stirred at 55°C for 13 min, 4 g of modified graphene oxide and 3 g of modified cellulose nanowhiskers were added, and the stirring reaction was continued for 15 min to obtain the reinforcing filler.

[0067] Comparative Example 1 The difference between this comparative example and Example 1 is that the polydopamine modified cellulose nanowhiskers are replaced by cellulose nanowhiskers, and the remaining steps and raw materials are the same as in Example 1.

[0068] The reinforcing filler was prepared by the following steps:

[0069] A1. 8 g of calcium chloride was added to 80 mL of deionized water, stirred until completely dissolved, 4 g of cellulose nanowhiskers was added, stirred for 10 min, 30% ammonia water was added to adjust the pH to 8, placed in a reaction kettle, 2 mL of carbon dioxide and 6 mL of air were introduced at a rate of 2.5 L / min, reacted at 30°C for 2 h, the solid was collected by filtration, and the solid was dried in an oven at 105°C for 20 min to obtain modified cellulose nanowhiskers;

[0070] A2. 4.5 g of graphene oxide was added to 50 mL of aluminum nitrate solution with a concentration of 0.3 mol / L, stirred uniformly, 5 g of urea was added, placed in a 150°C autoclave, and hydrothermal reaction was carried out for 6 h, cooled to room temperature, the gelatinous substance was collected by filtration, and calcination was carried out at 550°C for 2 h to obtain graphene oxide loaded with nano-aluminum oxide;

[0071] A3. 5 g of graphene oxide loaded with nano-aluminum oxide was added to 25 mL of deionized water, stirred uniformly, 5 mL of sulfuric acid with a mass fraction of 3% and 1.2 g of octamethylcyclotetrasiloxane were added, the temperature was raised to 60°C, and stirring reaction was carried out for 3 h, cooled to room temperature, filtered, washed with deionized water for 3 times, and dried in a 70°C oven for 10 min to obtain modified graphene oxide;

[0072] A4. 11 g of nano-cellulose and 9 g of chlorogenic acid modified chitosan were added to 20 mL of deionized water, stirred uniformly, 7 g of sodium hydroxide was added, stirring was carried out at 55°C for 13 min, 4 g of modified graphene oxide and 3 g of modified cellulose nanowhisker were added, and stirring reaction was continued for 15 min to obtain a reinforcing filler.

[0073] Comparative Example 2 The difference between this comparative example and Example 1 is that the modified cellulose nanowhisker is replaced by polydopamine modified cellulose nanowhisker, and the remaining steps and raw materials are the same as Example 1.

[0074] A1. 1.5 g of cellulose nanowhisker was added to 55 mL of Tris-HCl buffer with a pH of 8.5, stirred uniformly, 0.5 g of dopamine was added, and stirring was carried out for 4 h, filtered, washed with deionized water for 3 times, and dried in a 70°C oven for 10 min to obtain polydopamine modified cellulose nanowhisker;

[0075] A2. 4.5 g of graphene oxide was added to 50 mL of aluminum nitrate solution with a concentration of 0.3 mol / L, stirred uniformly, 5 g of urea was added, placed in a 150°C autoclave, and hydrothermal reaction was carried out for 6 h, cooled to room temperature, the gelatinous substance was collected by filtration, and calcination was carried out at 550°C for 2 h to obtain graphene oxide loaded with nano-aluminum oxide;

[0076] A3. 5 g of graphene oxide loaded with nano-aluminum oxide was added to 25 mL of deionized water, stirred uniformly, 5 mL of sulfuric acid with a mass fraction of 3% and 1.2 g of octamethylcyclotetrasiloxane were added, the temperature was raised to 60°C, and stirring reaction was carried out for 3 h, cooled to room temperature, filtered, washed with deionized water for 3 times, and dried in a 70°C oven for 10 min to obtain modified graphene oxide;

[0077] A4. 11 g nanocellulose and 9 g chlorogenic acid modified chitosan were added into 20 mL deionized water, stirred uniformly, 7 g sodium hydroxide was added, stirred at 55°C for 13 min, 4 g modified graphene oxide and 3 g modified cellulose nanowhisker were added, and the stirring reaction was continued for 15 min to obtain the reinforcing filler.

[0078] Comparative Example 3 The difference between this comparative example and Example 1 is that the nanometer alumina loaded graphene oxide is replaced by graphene oxide, and the remaining steps and raw materials are the same as Example 1.

[0079] The reinforcing filler was prepared by the following steps:

[0080] A1. 1.5 g cellulose nanowhisker was added into 55 mL Tris-HCl buffer with pH of 8.5, stirred uniformly, 0.5 g dopamine was added, stirred for 4 h, filtered, washed with deionized water for 3 times, and dried in an oven at 70°C for 10 min to obtain the polydopamine modified cellulose nanowhisker;

[0081] A2. 8 g calcium chloride was added into 80 mL deionized water, stirred until completely dissolved, 4 g polydopamine modified cellulose nanowhisker was added, stirred for 10 min, 30% ammonia water was added to adjust the pH to 8, and the reaction kettle was placed, 2 mL carbon dioxide and 6 mL air were introduced at a rate of 2.5 L / min, and the reaction was carried out at 30°C for 2 h. The solid was collected by filtration, and the solid was dried in an oven at 105°C for 20 min to obtain the modified cellulose nanowhisker;

[0082] A3. 5 g graphene oxide was added into 25 mL deionized water, stirred uniformly, 5 mL 3% sulfuric acid and 1.2 g octamethylcyclotetrasiloxane were added, the temperature was raised to 60°C, and the stirring reaction was carried out for 3 h. After cooling to room temperature, the mixture was filtered, washed with deionized water for 3 times, and dried in an oven at 70°C for 10 min to obtain the modified graphene oxide;

[0083] A4. 11 g nanocellulose and 9 g chlorogenic acid modified chitosan were added into 20 mL deionized water, stirred uniformly, 7 g sodium hydroxide was added, stirred at 55°C for 13 min, 4 g modified graphene oxide and 3 g modified cellulose nanowhisker were added, and the stirring reaction was continued for 15 min to obtain the reinforcing filler.

[0084] Comparative Example 4 The difference between this comparative example and Example 1 is that the modified graphene oxide is replaced by nanometer alumina loaded graphene oxide, and the remaining steps and raw materials are the same as Example 1.

[0085] The reinforcing filler was prepared by the following steps:

[0086] A1. 1.5 g of cellulose nanowhiskers was added into 55 mL of Tris-HCl buffer solution with pH of 8.5, stirred uniformly, 0.5 g of dopamine was added, stirred for 4 h, filtered, washed with deionized water for 3 times, dried in an oven at 70℃ for 10 min, to obtain polydopamine modified cellulose nanowhiskers;

[0087] A2. 8 g of calcium chloride was added into 80 mL of deionized water, stirred until completely dissolved, 4 g of polydopamine modified cellulose nanowhiskers was added, stirred for 10 min, 30% ammonia water was added to adjust the pH to 8, placed in a reaction kettle, 2 mL of carbon dioxide and 6 mL of air were introduced at a rate of 2.5 L / min, reacted at 30℃ for 2 h, the solid was collected by filtration, and the solid was dried in an oven at 105℃ for 20 min to obtain modified cellulose nanowhiskers;

[0088] A3. 4.5 g of graphene oxide was added into 50 mL of aluminum nitrate solution with a concentration of 0.3 mol / L, stirred uniformly, 5 g of urea was added, placed in a high-pressure kettle at 150℃, and subjected to hydrothermal reaction for 6 h, cooled to room temperature, and the gelatinous material was collected by filtration, and calcined at 550℃ for 2 h to obtain graphene oxide loaded with nano-aluminum oxide;

[0089] A4. 11 g of nanocellulose and 9 g of chlorogenic acid modified chitosan were added into 20 mL of deionized water, stirred uniformly, 7 g of sodium hydroxide was added, stirred at 55℃ for 13 min, 4 g of graphene oxide loaded with nano-aluminum oxide and 3 g of modified cellulose nanowhiskers were added, and the stirring reaction was continued for 15 min to obtain the reinforcing filler.

[0090] Comparative Example 5 The difference between this comparative example and Example 1 is that no nanocellulose and chlorogenic acid modified chitosan is added, and the remaining steps and raw materials are the same as Example 1.

[0091] The reinforcing filler was prepared by the following steps:

[0092] A1. 1.5 g of cellulose nanowhiskers was added into 55 mL of Tris-HCl buffer solution with pH of 8.5, stirred uniformly, 0.5 g of dopamine was added, stirred for 4 h, filtered, washed with deionized water for 3 times, dried in an oven at 70℃ for 10 min, to obtain polydopamine modified cellulose nanowhiskers;

[0093] A2. 8 g of calcium chloride was added to 80 mL of deionized water, stirred until completely dissolved, 4 g of polydopamine modified cellulose nanowhiskers was added, stirred for 10 min, 30% ammonia water was added to adjust the pH to 8, placed in a reaction kettle, 2 mL of carbon dioxide and 6 mL of air were introduced at a rate of 2.5 L / min, reacted at 30℃ for 2h, the solid was collected by filtration, and the solid was dried in an oven at 105℃ for 20 min to obtain modified cellulose nanowhiskers;

[0094] A3. 4.5 g of graphene oxide was added to 50 mL of 0.3 mol / L aluminum nitrate solution, stirred uniformly, 5 g of urea was added, placed in a 150℃ autoclave, and hydrothermal reaction was carried out for 6h, cooled to room temperature, and the gelatinous material was collected by filtration, and calcined at 550℃ for 2h to obtain graphene oxide loaded with nano-alumina;

[0095] A4. 5 g of graphene oxide loaded with nano-alumina was added to 25 mL of deionized water, stirred uniformly, 5 mL of 3% sulfuric acid and 1.2 g of octamethylcyclotetrasiloxane were added, the temperature was raised to 60℃, and the reaction was stirred for 3h, cooled to room temperature, filtered, washed with deionized water 3 times, and dried in an oven at 70℃ for 10 min to obtain modified graphene oxide;

[0096] A5. 20 mL of deionized water, 7 g of sodium hydroxide, 4 g of modified graphene oxide and 3 g of modified cellulose nanowhiskers were stirred at 55℃ for 15 min to obtain a reinforcing filler.

[0097] Example 2 A hard rock tunneling spoil resource modification process and method, comprising the following steps:

[0098] S1. The hard rock tunneling spoil was mixed with lime, stirred uniformly, covered and stewed for 8h, crushed and sieved to obtain pretreated spoil;

[0099] S2. The pretreated spoil, the powder soil stabilizer and the reinforcing filler prepared in example 1 were mixed, stirred at a speed of 500 r / min for 30 min, crushed and sieved to obtain a resource modified spoil;

[0100] The mass ratio of hard rock tunneling spoil to lime is 80:5;

[0101] The mass ratio of pretreated spoil, powder soil stabilizer and reinforcing filler prepared in example 1 is 80:4:8;

[0102] The powder soil stabilizer is a mixture of methyl sodium silicate, sodium alginate, sodium dodecylbenzenesulfonate, sodium chloride, lithium hydroxide and polycarboxylic acid superplasticizer in a mass ratio of 3:0.6:1:0.8:0.1:0.2.

[0103] Embodiment 3 A hard rock tunneling spoil resource utilization improvement process method, comprising the following steps:

[0104] S1. The hard rock tunneling spoil is mixed with quicklime, stirred uniformly, covered and stewed for 10h, crushed and sieved to obtain pretreated spoil;

[0105] S2. The pretreated spoil, the powder soil solidifying agent and the reinforcing filler prepared in Embodiment 1 are mixed, stirred and mixed at a speed of 550r / min for 35min, crushed and sieved to obtain the resource utilization improved spoil;

[0106] The mass ratio of the hard rock tunneling spoil to the quicklime is 90:6.

[0107] The mass ratio of the pretreated spoil, the powder soil solidifying agent and the reinforcing filler prepared in Embodiment 1 is 90:5:9.

[0108] The powder soil solidifying agent is mixed by methyl sodium silicate, sodium alginate, sodium dodecyl benzene sulfonate, sodium chloride, lithium hydroxide and polycarboxylic acid superplasticizer according to a mass ratio of 4:0.8:1.3:1:0.2:0.3.

[0109] Embodiment 4 A hard rock tunneling spoil resource utilization improvement process method, comprising the following steps:

[0110] S1. The hard rock tunneling spoil is mixed with quicklime, stirred uniformly, covered and stewed for 12h, crushed and sieved to obtain pretreated spoil;

[0111] S2. The pretreated spoil, the powder soil solidifying agent and the reinforcing filler prepared in Embodiment 1 are mixed, stirred and mixed at a speed of 600r / min for 40min, crushed and sieved to obtain the resource utilization improved spoil;

[0112] The mass ratio of the hard rock tunneling spoil to the quicklime is 100:7.

[0113] The mass ratio of the pretreated spoil, the powder soil solidifying agent and the reinforcing filler prepared in Embodiment 1 is 100:6:10.

[0114] The powder soil solidifying agent is mixed by methyl sodium silicate, sodium alginate, sodium dodecyl benzene sulfonate, sodium chloride, lithium hydroxide and polycarboxylic acid superplasticizer according to a mass ratio of 5:1:1.5:1.2:0.3:0.4.

[0115] Comparative Example 6 The difference between this comparative example and Embodiment 3 is that the reinforcing filler prepared in Embodiment 1 is replaced by the substance prepared in Comparative Example 1, and the remaining steps are implemented synchronously with Embodiment 3.

[0116] Comparative Example 7 The difference between this comparative example and Example 3 is that the reinforcing filler prepared in Example 1 is replaced by the substance prepared in Comparative Example 2, and the remaining steps are the same as in Example 3.

[0117] Comparative Example 8 The difference between this comparative example and Example 3 is that the reinforcing filler prepared in Example 1 is replaced by the substance prepared in Comparative Example 3, and the remaining steps are the same as in Example 3.

[0118] Comparative Example 9 The difference between this comparative example and Example 3 is that the reinforcing filler prepared in Example 1 is replaced by the substance prepared in Comparative Example 4, and the remaining steps are the same as in Example 3.

[0119] Comparative Example 10 The difference between this comparative example and Example 3 is that the reinforcing filler prepared in Example 1 is replaced by the substance prepared in Comparative Example 5, and the remaining steps are the same as in Example 3.

[0120] The performance of the resource-modified slag soil prepared in Examples 2-4 and Comparative Examples 6-10 is now detected.

[0121] The compressive strength of the resource-modified slag soil prepared above after 7d and 28d is tested using a strain-controlled unconfined compression instrument.

[0122] The test data is shown in Table 2 below:

[0123] Table 2

[0124]

[0125]

[0126] As can be seen from the data in Table 2, the mechanical properties of the concrete prepared by replacing the polydopamine-modified cellulose nanowhisker with the cellulose nanowhisker in Comparative Example 6 are decreased, which may be because the polydopamine-modified cellulose nanowhisker has better adhesion, which is conducive to the formation of calcium carbonate particles on the surface of the cellulose nanowhisker, thereby enhancing the mechanical properties of the slag soil-based concrete. However, in Comparative Example 6, the cellulose nanowhisker surface lacks polydopamine, so the mechanical properties of the slag soil-based concrete prepared are decreased.

[0127] In Comparative Example 7, the modified cellulose nanowhisker is replaced by the polydopamine-modified cellulose nanowhisker to prepare the reinforcing filler, which is added to the resource-modified slag soil to prepare the concrete, and the mechanical properties of the concrete are decreased, which may be because the polydopamine-modified cellulose nanowhisker forms calcium carbonate particles on the surface, and the formed nano-calcium carbonate particles can penetrate into the pores of the slag soil, thereby improving the density of the slag soil and enhancing the mechanical properties of the slag soil. However, in Comparative Example 7, the polydopamine-modified cellulose nanowhisker surface lacks polydopamine, so the mechanical properties of the slag soil-based concrete prepared are decreased.

[0128] The mechanical properties of the concrete prepared by adding the reinforcing filler prepared by replacing the modified graphene oxide in Example 1 with the graphene oxide in Comparative Example 8 into the resource-modified slag soil decrease, which can be because the nanometer alumina is formed on the surface of the graphene oxide, providing a large number of rough surfaces, increasing the contact area with the slag soil, and making the graphene oxide loaded with nanometer alumina closely combined with the slag soil, thereby improving the mechanical properties of the slag soil. Therefore, the mechanical properties of the slag soil-based concrete prepared by Comparative Example 8 decrease because the surface of the graphene oxide in Comparative Example 8 lacks nanometer alumina.

[0129] The mechanical properties of the concrete prepared by adding the reinforcing filler prepared by replacing the modified graphene oxide in Example 1 with the graphene oxide loaded with nanometer alumina in Comparative Example 9 into the resource-modified slag soil decrease, which can be because the octamethylcyclotetrasiloxane is grafted on the surface of the graphene oxide loaded with nanometer alumina, and the octamethylcyclotetrasiloxane can react with the organosilicon in the slag soil, thereby further enhancing the binding force between the modified graphene oxide and the slag soil and further enhancing the compactness of the slag soil, thereby improving the mechanical properties of the slag soil. Therefore, the mechanical properties of the slag soil-based concrete prepared by Comparative Example 9 decrease because the surface of the graphene oxide loaded with nanometer alumina in Comparative Example 9 lacks octamethylcyclotetrasiloxane.

[0130] The mechanical properties of the concrete prepared by adding the reinforcing filler prepared by replacing the modified graphene oxide in Example 1 with the graphene oxide loaded with nanometer alumina in Comparative Example 9 into the resource-modified slag soil decrease, which can be because the octamethylcyclotetrasiloxane is grafted on the surface of the graphene oxide loaded with nanometer alumina, and the octamethylcyclotetrasiloxane can react with the organosilicon in the slag soil, thereby further enhancing the binding force between the modified graphene oxide and the slag soil and further enhancing the compactness of the slag soil, thereby improving the mechanical properties of the slag soil. Therefore, the mechanical properties of the slag soil-based concrete prepared by Comparative Example 9 decrease because the surface of the graphene oxide loaded with nanometer alumina in Comparative Example 9 lacks octamethylcyclotetrasiloxane.

[0131] The data in Table 2 show that the resource-modified slag soil prepared in Examples 2-4 meets the performance requirements of the test, and the resource-modified slag soil prepared in Comparative Examples 6-10 does not meet the performance requirements of the standard, indicating that the resource-modified slag soil prepared by the present application has good mechanical properties and compactness.

[0132] In the description of the specification, the description of the terms "one embodiment", "example", "specific example", and the like means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In the specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0133] The above merely illustrates and describes the present application, and those skilled in the art can make various modifications or supplements to the described specific embodiments or adopt similar ways to replace, as long as the modifications or supplements do not deviate from the present application or exceed the scope defined by the present application, and should belong to the protection scope of the present application.

Claims

1. A hard rock tunneling muck resource utilization improvement process method, characterized in that, It comprises the following steps: S1. Mix the hard rock tunneling spoil with a dehydrating agent, stir evenly, cover and stew for 8-12 hours, crush, stir and mix to obtain pretreated spoil; S2. Mix the pretreated spoil, powder soil solidifying agent and reinforcing filler, stir and mix at a speed of 500-600 r / min for 30-40 min, crush, stir and mix to obtain resourceized improved spoil; The reinforcing filler is obtained by mixing and reacting modified cellulose nanowhiskers, modified graphene oxide, green acid modified chitosan and hydroxyethyl cellulose; The modified cellulose nanowhiskers are obtained by modifying cellulose nanowhiskers with polydopamine and then depositing calcium carbonate particles in situ; The modified graphene oxide is obtained by mixing graphene oxide, aluminum nitrate solution and urea, then performing hydrothermal reaction, and then reacting with octamethylcyclotetrasiloxane; The reinforcing filler is obtained by the following steps: A1. Add cellulose nanowhiskers to Tris-HCl buffer solution, stir evenly, add dopamine, stir for 3-5 h, filter, wash and dry to obtain polydopamine modified cellulose nanowhiskers; A2. Add calcium chloride to deionized water, stir until completely dissolved, add polydopamine modified cellulose nanowhiskers, stir evenly, add ammonia to adjust the pH to 7-9, place in a reaction kettle, pass in carbon dioxide and air, stir until the reaction is complete, then filter to collect the solid, and dry the solid to obtain modified cellulose nanowhiskers; A3. Add graphene oxide to aluminum nitrate solution, stir evenly, add urea, place in a high-pressure kettle at 140-160℃, perform hydrothermal reaction for 5-8 h, cool to room temperature, filter to collect the gelatinous material, and calcine at 500-600℃ for 1-3 h to obtain graphene oxide loaded with nano-alumina; A4. Add graphene oxide loaded with nano-alumina to deionized water, stir evenly, add sulfuric acid and octamethylcyclotetrasiloxane, heat to 55-65℃, stir for 2-4 h, cool to room temperature, filter, wash and dry to obtain modified graphene oxide; A5. Add nanocellulose and green acid modified chitosan to deionized water, stir evenly, add sodium hydroxide, stir at 50-60℃ for 10-15 min, add modified graphene oxide and modified cellulose nanowhiskers, continue to stir for 10-20 min to obtain the reinforcing filler.

2. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The dehydrating agent is quicklime, and the mass ratio of hard rock tunneling spoil to dehydrating agent is (80-100):(5-7).

3. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The mass ratio of pretreated spoil, powder soil solidifying agent and reinforcing filler is (80-100):(4-6):(8-10); The powder soil solidifying agent is obtained by mixing sodium methyl silicate, sodium alginate, sodium dodecylbenzenesulfonate, sodium chloride, lithium hydroxide and polycarboxylic acid superplasticizer in a mass ratio of (3-5):(0.6-1):(1-1.5):(0.8-1.2):(0.1-0.3):(0.2-0.4).

4. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The concentration of the aluminum nitrate solution is 0.2-0.4 mol / L; the hydrothermal reaction temperature is 140-160 DEG C, and the hydrothermal reaction time is 5-8 h.

5. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The particle size of the graphene oxide is 0.2-1 mu m.

6. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The cellulose nanowhisker is prepared by the following steps: The microcrystalline cellulose is added into a sulfuric acid solution, stirred uniformly, and placed in a 35-45 DEG C stirring reactor for 1-3 h, then deionized water is added for dilution to end the reaction, the collected nanowhisker is dispersed in deionized water, treated by dialysis, and freeze-dried to obtain the cellulose nanowhisker.

7. The hard rock tunneling muck resource utilization improvement process and method of claim 6, wherein, The dosage ratio of the microcrystalline cellulose and the sulfuric acid solution is (5-7) g:(80-100) mL.

8. The hard rock tunneling and muck resource utilization and improvement process and method of claim 1, wherein, The green acid modified chitosan is prepared by the following steps: The chitosan is added into an acetic acid solution, stirred uniformly to obtain a chitosan solution, the green acid, N-hydroxysuccinimide and 1-ethyl-(3-dimethylaminopropyl) carbonyl diimide hydrochloride are added into ethanol, stirred and mixed, then added into the chitosan solution, stirred in an ice water bath until the reaction is completed, centrifuged to collect the supernatant, and the supernatant is freeze-dried to obtain the green acid modified chitosan.

9. The hard rock tunneling muck resource utilization improvement process and method of claim 8, wherein, The dosage ratio of the chitosan, the acetic acid solution, the green acid, N-hydroxysuccinimide, 1-ethyl-(3-dimethylaminopropyl) carbonyl diimide hydrochloride and ethanol is (1-3) g:(45-55) mL:(0.4-0.6) g:(0.1-0.3) g:(0.2-0.24) g:(18-22) mL.

10. The hard rock tunneling muck resource utilization improvement process and method of claim 1, wherein, The mass ratio of the modified cellulose nanowhisker, the modified graphene oxide, the green acid modified chitosan and the hydroxyethyl cellulose is (2-4):(3-5):(8-10):(10-12).

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