Silt dam material and preparation method thereof

Abstract

The invention belongs to the field of silt dam materials, and particularly relates to a silt dam material and a preparation method thereof. The silt dam material provided by the invention is prepared from the following components in parts by weight: 80 to 98 parts of loess, 20 to 28 parts of wood fiber, 26 to 38 parts of slag powder, 22 to 26 parts of cement, 10 to 16 parts of fly ash, 8 to 16 parts of epoxy resin, 6 to 8 parts of PVP-VA (Polyvinyl Pyrrolidone-Vinyl Acetate) copolymer, 3 to 6 parts of citrate, 5 to 9 parts of reinforcing agent, 3 to 5 parts of water reducing agent and 30 to 60 parts of water. The glass transition temperature of the PVP-VA copolymer is greater than or equal to 23 DEG C; the citrate comprises tributyl citrate, triethyl citrate and trioctyl citrate, and the mass ratio of the tributyl citrate to the triethyl citrate to the trioctyl citrate is (1-4): (0.5-2): 1. The silt dam material provided by the invention has better compressive strength and water stability coefficient, and can improve the safety of a dam body during use and reduce the risk of dam break.

Description

Technical Field

[0001] The invention belongs to the field of silt dam materials, and in particular relates to a silt dam material and a preparation method thereof. Background Art

[0002] A silt dam is a dam structure built in ditches at all levels in areas of soil erosion for the purpose of blocking mud and silting up the land. The land formed by blocking mud and silting up is called a dam land. In a river basin ditch, a dam used for silting up land is called a silt dam or production dam. The construction of multiple silt dams in a ditch is an important and unique ditch control engineering system in areas of severe soil erosion in the Loess Plateau of China. The main purpose is to retain floodwater, block mud, silt up land, store water, build farmland, develop agricultural production, and reduce sediment in the Yellow River.

[0003] Adaptive silt dam is a soil and water conservation engineering measure built in areas with severe soil erosion, especially in the Loess Plateau, to intercept sediment, maintain water and soil, and reclaim land. During the design, construction and operation of this type of silt dam, special attention is paid to adaptability to ensure its stable and safe operation under various natural conditions. When designing the silt dam, the stability, flood resistance and erosion resistance of the dam body must be considered. Appropriate dam materials and engineering technologies are used. The silt dam can adapt to changes in terrain, geology and hydrological conditions. Through reasonable spillway and water release structure design, it can effectively adjust the reservoir capacity and discharge, and reduce the downstream flood control pressure.

[0004] When building a silt dam, the materials used are crucial. Existing silt dams are mostly made of loess and some additional adhesives. The adhesives generally include cement, slag powder and the like, and the components are relatively simple. Since loess is collapsible, it is easy to sink and deform when it comes into contact with water, which may have an adverse effect on the stability of the dam body. The shear strength of loess is relatively low, especially under the action of water, its strength will be further reduced, increasing the risk of dam landslide or dam breach, and in long-term heavy rain weather, it is easy to cause dam breach. Summary of the invention

[0005] In view of this, an object of the present invention is to provide a silt dam material and a preparation method thereof. The silt dam material provided by the present invention has good compressive strength and water stability coefficient, which can improve the safety of the dam body during use and reduce the risk of dam breach.

[0006] The present invention provides a silt dam material, which comprises the following components in parts by weight:

[0007] Loess 80~98 parts;

[0008] 20-28 parts of wood fiber;

[0009] 26-38 parts of slag powder;

[0010] Cement 22~26 parts;

[0011] 10-16 parts of fly ash;

[0012] Epoxy resin 8-16 parts;

[0013] 6-8 parts of PVP-VA copolymer;

[0014] 3-6 parts of citrate;

[0015] Enhancer 5~9 parts;

[0016] 3~5 parts of water reducing agent;

[0017] 30~60 parts of water;

[0018] The glass transition temperature of the PVP-VA copolymer is ≥23°C;

[0019] The citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate, and the mass ratio of the tributyl citrate, triethyl citrate and trioctyl citrate is (1-4):(0.5-2):1.

[0020] Preferably, the water reducer is one or more of a polycarboxylic acid water reducer, an aminosulfonate water reducer and a naphthalene water reducer.

[0021] Preferably, the enhancer includes one or more of sodium sulfate, potassium sulfate and calcium oxide.

[0022] Preferably, the mass ratio of the sodium sulfate, potassium sulfate and calcium oxide is (2-4):(1-3):3.

[0023] Preferably, the cement is ordinary Portland cement or composite Portland cement.

[0024] The present invention provides a method for preparing the silt dam material described in the above technical solution, comprising the following steps:

[0025] a) mixing loess, wood fiber, slag powder, cement, fly ash, epoxy resin, PVP-VA copolymer, citrate, reinforcing agent, water reducing agent and water to obtain mixed soil;

[0026] b) compacting the mixed soil, covering it with a film, and curing it to obtain a silt dam material.

[0027] Preferably, in step a), the mixing process specifically includes:

[0028] a1) mixing wood fiber, slag powder, cement and fly ash to obtain a mixture A;

[0029] a2) mixing the mixture A with water to obtain a mixture B;

[0030] a3) mixing the mixture B with an epoxy resin, allowing the mixture to stand, and then mixing the mixture with a PVP-VA copolymer and a citrate to obtain a mixture C;

[0031] a4) mixing the mixture C with the mixture D to obtain a mixture E; the mixture D comprises a water reducing agent, a reinforcing agent and water;

[0032] a5) Mixing the mixture E with loess to obtain mixed soil.

[0033] Preferably, step a2) specifically includes:

[0034] Add water to the mixture A and mix at a low speed for a period of time; then continue to add water and mix at a high speed for a period of time to obtain a mixture B;

[0035] The rotation speed of the low-speed mixing is 50-80 rpm, and the time is 30-40 min; the rotation speed of the high-speed mixing is 300-400 rpm, and the time is 50-65 min.

[0036] Preferably, in step a3), the mixing method with the PVP-VA copolymer and the citrate is forward and reverse intermittent stirring, and the specific process includes: stirring counterclockwise for 3 to 5 minutes, standing for 1 to 2 minutes, stirring clockwise for 3 to 4 minutes, and standing for 1 to 2 minutes, and the above process is repeated several times; wherein the rotation speed of the counterclockwise stirring is 100 to 120 rpm, and the rotation speed of the clockwise stirring is 130 to 150 rpm.

[0037] Preferably, in step b), the compaction degree of the mixed soil after compaction is 90-95%.

[0038] Compared with the prior art, the silt dam material and the preparation method thereof provided by the present invention have at least the following beneficial effects:

[0039] (1) PVP-VA copolymer (vinyl pyrrolidone-vinyl acetate copolymer) is added to the silt dam material of the present invention. Since vinyl pyrrolidone has good polymer film-forming properties, the copolymer can easily form a thin film or a network structure in the soil, which is convenient for strengthening the bonding force between soil particles and improving the compressive resistance of the soil. At the same time, the molecular chain of vinyl acetate in the copolymer has an ester functional group, which can react with cations such as calcium and magnesium or water molecules in the soil to form cross-linking points, thereby facilitating the tight connection between soil particles and polymer molecular chains, thereby enhancing the bonding force between soil particles.

[0040] (2) The silt dam material of the present invention contains tributyl citrate, triethyl citrate and trioctyl citrate in a specific proportion, so that the material has superior performance and is convenient for use of the dam body.

[0041] (3) The silt dam material of the present invention has good compressive strength and water stability coefficient, which, to a certain extent, improves the safety of the dam body during use and reduces the risk of dam breach. DETAILED DESCRIPTION

[0042] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0043] The present invention provides a silt dam material, which comprises the following components in parts by weight:

[0044] Loess 80~98 parts;

[0045] 20-28 parts of wood fiber;

[0046] 26-38 parts of slag powder;

[0047] Cement 22~26 parts;

[0048] 10-16 parts of fly ash;

[0049] Epoxy resin 8-16 parts;

[0050] 6-8 parts of PVP-VA copolymer;

[0051] 3-6 parts of citrate;

[0052] Enhancer 5~9 parts;

[0053] 3~5 parts of water reducing agent;

[0054] 30~60 parts of water.

[0055] In the silt dam material provided by the present invention, the natural density of the loess is preferably 1.6-1.8 g / cm 3 , more preferably 1.68 g / cm 3; The content of clay particles and fine powder particles (particle size less than 0.075 mm) in the particle composition of the loess preferably accounts for 45-55% of the total mass, more preferably 49%, and the content of sand particles (particle size between 0.075 mm and 2 mm) preferably accounts for 30-40% of the total mass, more preferably 35%. In the present invention, the content of the loess in the silt dam material can be specifically 80 parts by weight, 81 parts by weight, 82 parts by weight, 83 parts by weight, 84 parts by weight, 85 parts by weight, 86 parts by weight, 87 parts by weight, 88 parts by weight, 89 parts by weight, 90 parts by weight, 91 parts by weight, 92 parts by weight, 93 parts by weight, 94 parts by weight, 95 parts by weight, 96 parts by weight, 97 parts by weight or 98 parts by weight.

[0056] In the silt dam material provided by the present invention, the diameter of the wood fiber is preferably 30-40 μm; the length of the wood fiber is preferably 6-9 mm; the tensile strength of the wood fiber is preferably ≥100 MPa. In the present invention, the content of the wood fiber in the silt dam material can be specifically 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, 25 parts by weight, 26 parts by weight, 27 parts by weight or 28 parts by weight.

[0057] In the silt dam material provided by the present invention, the specific surface area of ​​the slag powder is preferably 400-550m 2 / kg; the density of the slag powder is preferably 2.8~3.2g / cm 3 In the present invention, the content of the slag powder in the silt dam material can be specifically 26 parts by weight, 27 parts by weight, 28 parts by weight, 29 parts by weight, 30 parts by weight, 31 parts by weight, 32 parts by weight, 33 parts by weight, 34 parts by weight, 35 parts by weight, 36 parts by weight, 37 parts by weight or 38 parts by weight.

[0058] In the silt dam material provided by the present invention, the cement is preferably ordinary silicate cement or composite silicate cement; wherein the grade of the composite silicate cement is preferably P.C42.5, and the composite silicate cement of the above grade is provided by Guangzhou Qiangsheng Cement Grinding Co., Ltd. In the present invention, the content of the cement in the silt dam material can be specifically 22 parts by weight, 22.5 parts by weight, 23 parts by weight, 23.5 parts by weight, 24 parts by weight, 24.5 parts by weight, 25 parts by weight, 25.5 parts by weight or 26 parts by weight.

[0059] In the silt dam material provided by the present invention, the specific surface area of ​​the fly ash is preferably 300-500m 2 / kg; the 7-day activity index of the fly ash is preferably ≥60%; the 28-day activity index of the fly ash is preferably ≥90%; the density of the fly ash is preferably 2-2.5g / cm 3, more preferably 2.2 g / cm 3 In the present invention, the content of fly ash in the silt dam material can be specifically 10 parts by weight, 10.5 parts by weight, 11 parts by weight, 11.5 parts by weight, 12 parts by weight, 12.5 parts by weight, 13 parts by weight, 13.5 parts by weight, 14 parts by weight, 14.5 parts by weight, 15 parts by weight, 15.5 parts by weight or 16 parts by weight.

[0060] In the silt dam material provided by the present invention, the grade of the epoxy resin is preferably LX-02F, and the above grade of epoxy resin is provided by Shanghai Yuanxi Industrial Service Co., Ltd. In the present invention, the content of the epoxy resin in the silt dam material can be specifically 8 parts by weight, 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, 14 parts by weight, 15 parts by weight or 16 parts by weight.

[0061] In the silt dam material provided by the present invention, the glass transition temperature of the PVP-VA copolymer (vinyl pyrrolidone-vinyl acetate copolymer) is ≥23°C; the mass ratio of the VP unit to the VA unit in the PVP-VA copolymer is preferably (50-70): (50-30), more preferably 60:40; the number average molecular weight (Mn) of the PVP-VA copolymer is preferably 70000-80000 g / mol. In the present invention, the content of the PVP-VA copolymer in the silt dam material can be specifically 6 parts by weight, 6.2 parts by weight, 6.5 parts by weight, 6.7 parts by weight, 7 parts by weight, 7.3 parts by weight, 7.5 parts by weight, 7.8 parts by weight or 8 parts by weight.

[0062] In the silt dam material provided by the present invention, the citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate; the mass ratio of the tributyl citrate, triethyl citrate and trioctyl citrate is (1-4): (0.5-2): 1, wherein the mass ratio of the tributyl citrate and trioctyl citrate can be 1: 1, 1.5: 1, 2: 1, 2.5: 1, 3: 1, 3.5: 1 or 4: 1, and the mass ratio of the triethyl citrate and trioctyl citrate can be 0.5: 1, 1: 1, 1.5: 1 or 2: 1. In the present invention, the content of the citrate ester in the silt dam material can be 3 parts by weight, 3.2 parts by weight, 3.5 parts by weight, 3.7 parts by weight, 4 parts by weight, 4.2 parts by weight, 4.5 parts by weight, 4.7 parts by weight, 5 parts by weight, 5.2 parts by weight, 5.5 parts by weight, 5.7 parts by weight or 6 parts by weight.

[0063] In the silt dam material provided by the present invention, the reinforcing agent preferably includes one or more of sodium sulfate, potassium sulfate and calcium oxide; the mass ratio of the sodium sulfate, potassium sulfate and calcium oxide is preferably (2-4): (1-3): 3, wherein the mass ratio of the sodium sulfate and calcium oxide can be specifically 2: 3, 2.5: 3, 3: 3, 3.5: 3 or 4: 3, and the mass ratio of the potassium sulfate and calcium oxide can be specifically 1: 3, 1.5: 3, 2: 3, 2.5: 3 or 3: 3. In the present invention, the content of the reinforcing agent in the silt dam material can be specifically 5 parts by weight, 5.5 parts by weight, 6 parts by weight, 6.5 parts by weight, 7 parts by weight, 7.5 parts by weight, 8 parts by weight, 8.5 parts by weight or 9 parts by weight.

[0064] In the silt dam material provided by the present invention, the water reducer is preferably one or more of a polycarboxylic acid water reducer, an aminosulfonate water reducer and a naphthalene water reducer; wherein the polycarboxylic acid water reducer is preferably KH-4, and the polycarboxylic acid water reducer of the above grade is provided by Wuhan Huaxuan High-tech Co., Ltd. In the present invention, the content of the water reducer in the silt dam material can be specifically 3 parts by weight, 3.2 parts by weight, 3.5 parts by weight, 3.7 parts by weight, 4 parts by weight, 4.2 parts by weight, 4.5 parts by weight, 4.7 parts by weight or 5 parts by weight.

[0065] In the silt dam material provided by the present invention, the content of water in the silt dam material can specifically be 30 parts by weight, 31 parts by weight, 32 parts by weight, 33 parts by weight, 34 parts by weight, 35 parts by weight, 36 parts by weight, 37 parts by weight, 38 parts by weight, 39 parts by weight, 40 parts by weight, 41 parts by weight, 42 parts by weight, 43 parts by weight, 44 parts by weight, 45 parts by weight, 46 parts by weight, 47 parts by weight, 48 parts by weight, 49 parts by weight, 50 parts by weight, 51 parts by weight, 52 parts by weight, 53 parts by weight, 54 parts by weight, 55 parts by weight, 56 parts by weight, 57 parts by weight, 58 parts by weight, 59 parts by weight or 60 parts by weight.

[0066] The present invention also provides a method for preparing the silt dam material described in the above technical solution, comprising the following steps:

[0067] a) mixing loess, wood fiber, slag powder, cement, fly ash, epoxy resin, PVP-VA copolymer, citrate, reinforcing agent, water reducing agent and water to obtain mixed soil;

[0068] b) compacting the mixed soil, covering it with a film, and curing it to obtain a silt dam material.

[0069] In the preparation method provided by the present invention, in step a), the mixing process specifically includes:

[0070] a1) mixing wood fiber, slag powder, cement and fly ash to obtain a mixture A;

[0071] a2) mixing the mixture A with water to obtain a mixture B;

[0072] a3) mixing the mixture B with an epoxy resin, allowing the mixture to stand, and then mixing the mixture with a PVP-VA copolymer and a citrate to obtain a mixture C;

[0073] a4) mixing the mixture C with the mixture D to obtain a mixture E; the mixture D comprises a water reducing agent, a reinforcing agent and water;

[0074] a5) Mixing the mixture E with loess to obtain mixed soil.

[0075] In the above mixing process provided by the present invention, in step a1), the mixing temperature is preferably 15-35° C., more preferably 25° C.; the mixing time is preferably 20-35 min, more preferably 28 min.

[0076] In the above mixing process provided by the present invention, step a2) specifically comprises: adding water to the mixture A, mixing at a low speed for a period of time; then continuing to add water, mixing at a high speed for a period of time, to obtain a mixture B. The rotation speed of the low-speed mixing is preferably 50-80 rpm, more preferably 70 rpm, the temperature is preferably 15-35°C, more preferably 25°C, and the time is preferably 30-40 min, more preferably 35 min; the rotation speed of the high-speed mixing is preferably 300-400 rpm, more preferably 350 rpm, the temperature is preferably 15-35°C, more preferably 25°C, and the time is preferably 50-65 min, more preferably 55 min.

[0077] In the above-mentioned mixing process provided by the present invention, in step a3), the temperature for mixing the mixture B and the epoxy resin is preferably 60-70°C, more preferably 65°C; the time for mixing the mixture B and the epoxy resin is preferably 10-15min, more preferably 13min; the standing temperature is preferably 60-70°C, more preferably 65°C; the standing time is preferably 1-3h, more preferably 2h.

[0078] In the above-mentioned mixing process provided by the present invention, in step a3), the temperature for mixing with the PVP-VA copolymer and the citrate is preferably 60-70°C, more preferably 65°C; the time for mixing with the PVP-VA copolymer and the citrate is preferably 2-3h, more preferably 2.5h. In the present invention, the method for mixing with the PVP-VA copolymer and the citrate is preferably forward and reverse intermittent stirring, and the specific process includes: stirring counterclockwise for 3-5min, standing for 1-2min, stirring clockwise for 3-4min, and standing for 1-2min, and the above process is repeated several times; wherein the rotation speed of the counterclockwise stirring is preferably 100-120rpm, more preferably 110rpm, and the rotation speed of the clockwise stirring is preferably 130-150rpm, more preferably 140rpm.

[0079] In the above-mentioned mixing process provided by the present invention, in step a4), the temperature of the mixture D is preferably 30-35°C, more preferably 33°C; the mixing temperature is preferably 55-65°C, more preferably 60°C; the mixing time is preferably 25-35min, more preferably 28min.

[0080] In the above-mentioned mixing process provided by the present invention, in step a5), the mixing temperature is preferably 50-60°C, more preferably 55°C; the mixing speed is preferably 150-200rpm, more preferably 180rpm; the mixing time is preferably 1-1.5h, more preferably 1.3h.

[0081] In the preparation method provided by the present invention, in step b), the compaction degree of the mixed soil after compaction is preferably 90-95%, more preferably 93%; the curing time is preferably 5-10 days, specifically 5 days, 6 days, 7 days, 8 days, 9 days or 10 days.

[0082] For the purpose of greater clarity, the present invention is described in detail with reference to the following examples and comparative examples.

[0083] In the following embodiments and comparative examples of the present invention, the cement used is composite silicate cement, purchased from Guangzhou Qiangsheng Cement Grinding Co., Ltd., with a product brand of P.C42.5; the water reducer used is a polycarboxylic acid water reducer, purchased from Wuhan Huaxuan High-tech Co., Ltd., with a product brand of KH-4; the natural density of the loess used is 1.68 g / cm 3In the particle composition of loess, clay particles and fine powder particles (particle size less than 0.075mm) account for about 49% of the total mass, and sand particles (particle size between 0.075mm and 2mm) account for 35% of the total mass; the diameter of the wood fiber used is 30~40μm, the length is 6~9mm, and the tensile strength is 100MPa; the specific surface area of ​​the slag powder used is 400~550m 2 / kg, density is 2.8~3.2g / cm 3 The specific surface area of ​​fly ash used is 300~500m 2 / kg, 7-day activity index ≥60%, 28-day activity index ≥90%, density 2.2g / cm 3 ; The glass transition temperature of the PVP-VA copolymer used is greater than 23°C, the mass ratio of VP unit to VA unit in the copolymer is 60:40, and the number average molecular weight (Mn) of the copolymer is 70,000~80,000 g / mol; The epoxy resin used was purchased from Shanghai Yuanxi Industrial Service Co., Ltd., and the product brand is LX-02F.

[0084] In the following examples and comparative examples of the present invention, unless otherwise specified, related operations are carried out at room temperature (25° C.) and normal pressure (0.1 MPa).

[0085] Example 1

[0086] (1) Raw material composition

[0087] The composition includes the following components by weight: 80 parts of loess, 20 parts of wood fiber, 26 parts of slag powder, 22 parts of cement, 10 parts of fly ash, 8 parts of epoxy resin, 6 parts of PVP-VA copolymer, 3 parts of citrate, 30 parts of water, 5 parts of reinforcing agent, and 3 parts of water reducing agent;

[0088] The citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate, wherein the weight ratio of tributyl citrate, triethyl citrate and trioctyl citrate is 2:1:1;

[0089] The enhancer includes sodium sulfate, potassium sulfate and calcium oxide, wherein the weight ratio of sodium sulfate, potassium sulfate and calcium oxide is 3:2:3.

[0090] (2) Preparation of silt dam materials, including the following steps:

[0091] S1: Put wood fiber, slag powder, cement and fly ash into a container and stir and mix them for 28 minutes to obtain mixture A;

[0092] S2: Add water to mixture A and stir at a low speed for 35 minutes. After stirring, continue to add water and stir at a high speed for 55 minutes to obtain mixture B. When stirring at a low speed, the speed is 70 rpm, and when stirring at a high speed, the speed is 350 rpm;

[0093] S3: Heat the mixture B to 65°C, add epoxy resin to the mixture B, stir for 13 minutes, and let it stand at a constant temperature for 2 hours. Then, add PVP-VA copolymer and citrate, stir for 2.5 hours, and use positive and negative interval stirring to mix the various substances evenly to obtain a mixture C; when using positive and negative interval stirring, stir counterclockwise for 4 minutes, let it stand for 1.5 minutes, then stir clockwise for 3.5 minutes, and then let it stand for 1.5 minutes. When stirring counterclockwise, the rotation speed is 110 rpm, and when stirring clockwise, the rotation speed is 140 rpm;

[0094] S4: Mix water, enhancer and water reducer evenly, heat to 33°C to obtain mixture D, and let stand for later use;

[0095] S5: Add mixture D to mixture C while stirring. After complete addition, control the temperature at 60° C. and continue stirring for 28 minutes to obtain mixture E.

[0096] S6: Mix the loess with the mixture E and stir for 1.3 h. The temperature is controlled at 55°C and the rotation speed is 180 rpm to obtain the mixed soil. The mixed soil is compacted. The compaction degree of the compacted mixed soil is 93%;

[0097] S7: Cover with a film and cure the compacted mixed soil for 7 days to obtain a finished product.

[0098] Example 2

[0099] (1) Raw material composition

[0100] The composition includes the following components by weight: 89 parts of loess, 24 parts of wood fiber, 32 parts of slag powder, 24 parts of cement, 13 parts of fly ash, 12 parts of epoxy resin, 7 parts of PVP-VA copolymer, 4.5 parts of citrate, 45 parts of water, 7 parts of reinforcing agent, and 4 parts of water reducing agent;

[0101] The citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate, wherein the weight ratio of tributyl citrate, triethyl citrate and trioctyl citrate is 2:1:1;

[0102] The enhancer includes sodium sulfate, potassium sulfate and calcium oxide, wherein the weight ratio of sodium sulfate, potassium sulfate and calcium oxide is 3:2:3.

[0103] (2) Preparation of silt dam materials, including the following steps:

[0104] S1: Put wood fiber, slag powder, cement and fly ash into a container and stir and mix them for 28 minutes to obtain mixture A;

[0105] S2: Add water to mixture A and stir at a low speed for 35 minutes. After stirring, continue to add water and stir at a high speed for 55 minutes to obtain mixture B. When stirring at a low speed, the speed is 70 rpm, and when stirring at a high speed, the speed is 350 rpm;

[0106] S3: Heat the mixture B to 65°C, add epoxy resin to the mixture B, stir for 13 minutes, and let it stand at a constant temperature for 2 hours. Then, add PVP-VA copolymer and citrate, stir for 2.5 hours, and use positive and negative interval stirring to mix the various substances evenly to obtain a mixture C; when using positive and negative interval stirring, stir counterclockwise for 4 minutes, let it stand for 1.5 minutes, then stir clockwise for 3.5 minutes, and then let it stand for 1.5 minutes. When stirring counterclockwise, the rotation speed is 110 rpm, and when stirring clockwise, the rotation speed is 140 rpm;

[0107] S4: Mix water, enhancer and water reducer evenly, heat to 33°C to obtain mixture D, and let stand for later use;

[0108] S5: Add mixture D to mixture C while stirring. After complete addition, control the temperature at 60° C. and continue stirring for 28 minutes to obtain mixture E.

[0109] S6: Mix the loess with the mixture E and stir for 1.3 h. The temperature is controlled at 55°C and the rotation speed is 180 rpm to obtain the mixed soil. The mixed soil is compacted. The compaction degree of the compacted mixed soil is 93%;

[0110] S7: Cover with a film and cure the compacted mixed soil for 7 days to obtain a finished product.

[0111] Example 3

[0112] (1) Raw material composition

[0113] The following components are included by weight: 98 parts of loess, 28 parts of wood fiber, 38 parts of slag powder, 26 parts of cement, 16 parts of fly ash, 16 parts of epoxy resin, 8 parts of PVP-VA copolymer, 6 parts of citrate, 60 parts of water, 9 parts of reinforcing agent, and 5 parts of water reducing agent;

[0114] The citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate, wherein the weight ratio of tributyl citrate, triethyl citrate and trioctyl citrate is 2:1:1;

[0115] The enhancer includes sodium sulfate, potassium sulfate and calcium oxide, wherein the weight ratio of sodium sulfate, potassium sulfate and calcium oxide is 3:2:3.

[0116] (2) Preparation of silt dam materials, including the following steps:

[0117] S1: Put wood fiber, slag powder, cement and fly ash into a container and stir and mix them for 28 minutes to obtain mixture A;

[0118] S2: Add water to mixture A and stir at a low speed for 35 minutes. After stirring, continue to add water and stir at a high speed for 55 minutes to obtain mixture B. When stirring at a low speed, the speed is 70 rpm, and when stirring at a high speed, the speed is 350 rpm;

[0119] S3: Heat the mixture B to 65°C, add epoxy resin to the mixture B, stir for 13 minutes, and let it stand at a constant temperature for 2 hours. Then, add PVP-VA copolymer and citrate, stir for 2.5 hours, and use positive and negative interval stirring to mix the various substances evenly to obtain a mixture C; when using positive and negative interval stirring, stir counterclockwise for 4 minutes, let it stand for 1.5 minutes, then stir clockwise for 3.5 minutes, and then let it stand for 1.5 minutes. When stirring counterclockwise, the rotation speed is 110 rpm, and when stirring clockwise, the rotation speed is 140 rpm;

[0120] S4: Mix water, enhancer and water reducer evenly, heat to 33°C to obtain mixture D, and let stand for later use;

[0121] S5: Add mixture D to mixture C while stirring. After complete addition, control the temperature at 60° C. and continue stirring for 28 minutes to obtain mixture E.

[0122] S6: Mix the loess with the mixture E and stir for 1.3 h. The temperature is controlled at 55°C and the rotation speed is 180 rpm to obtain the mixed soil. The mixed soil is compacted. The compaction degree of the compacted mixed soil is 93%;

[0123] S7: Cover with a film and cure the compacted mixed soil for 7 days to obtain a finished product.

[0124] Example 4

[0125] The same components as those in Example 1 are followed, but the preparation method is different from that in Example 1 in that in step S7, a film is covered and the compacted mixed soil is cured for 5 days to obtain a finished product.

[0126] Example 5

[0127] The same components as those in Example 1 are followed, but the preparation method is different from that in Example 1 in that in step S7, a film is covered and the compacted mixed soil is cured for 10 days to obtain a finished product.

[0128] Comparative Example 1

[0129] (1) Raw material composition

[0130] The composition includes the following components by weight: 80 parts of loess, 20 parts of wood fiber, 26 parts of slag powder, 22 parts of cement, 10 parts of fly ash, 8 parts of epoxy resin, 6 parts of PVP-VA copolymer, 30 parts of water, 5 parts of reinforcing agent, and 3 parts of water reducing agent;

[0131] The enhancer includes sodium sulfate, potassium sulfate and calcium oxide, wherein the weight ratio of sodium sulfate, potassium sulfate and calcium oxide is 3:2:3.

[0132] (2) Preparation of silt dam materials, including the following steps:

[0133] S1: Put wood fiber, slag powder, cement and fly ash into a container and stir and mix them for 28 minutes to obtain mixture A;

[0134] S2: Add water to mixture A and stir at a low speed for 35 minutes. After stirring, continue to add water and stir at a high speed for 55 minutes to obtain mixture B. When stirring at a low speed, the speed is 70 rpm, and when stirring at a high speed, the speed is 350 rpm;

[0135] S3: Heat the mixture B to 65°C, add epoxy resin to the mixture B, stir for 13 minutes, and let it stand at a constant temperature for 2 hours. Then, add PVP-VA copolymer, stir for 2.5 hours, and use positive and negative interval stirring to mix the various substances evenly to obtain a mixture C; when using positive and negative interval stirring, stir counterclockwise for 4 minutes, let it stand for 1.5 minutes, then stir clockwise for 3.5 minutes, and then let it stand for 1.5 minutes. When stirring counterclockwise, the rotation speed is 110 rpm, and when stirring clockwise, the rotation speed is 140 rpm;

[0136] S4: Mix water, enhancer and water reducer evenly, heat to 33°C to obtain mixture D, and let stand for later use;

[0137] S5: Add mixture D to mixture C while stirring. After complete addition, control the temperature at 60° C. and continue stirring for 28 minutes to obtain mixture E.

[0138] S6: Mix the loess with the mixture E and stir for 1.3 h. The temperature is controlled at 55°C and the rotation speed is 180 rpm to obtain the mixed soil. The mixed soil is compacted. The compaction degree of the compacted mixed soil is 93%;

[0139] S7: Cover with a film and cure the compacted mixed soil for 7 days to obtain a finished product.

[0140] Comparative Example 2

[0141] (1) Raw material composition

[0142] The composition includes the following components by weight: 80 parts of loess, 20 parts of wood fiber, 26 parts of slag powder, 22 parts of cement, 10 parts of fly ash, 8 parts of epoxy resin, 30 parts of water, 5 parts of reinforcing agent, and 3 parts of water reducing agent;

[0143] The enhancer includes sodium sulfate, potassium sulfate and calcium oxide, wherein the weight ratio of sodium sulfate, potassium sulfate and calcium oxide is 3:2:3.

[0144] (2) Preparation of silt dam materials, including the following steps:

[0145] S1: Put wood fiber, slag powder, cement and fly ash into a container and stir and mix them for 28 minutes to obtain mixture A;

[0146] S2: Add water to mixture A and stir at a low speed for 35 minutes. After stirring, continue to add water and stir at a high speed for 55 minutes to obtain mixture B. When stirring at a low speed, the speed is 70 rpm, and when stirring at a high speed, the speed is 350 rpm;

[0147] S3: Heat the mixture B to 65°C, add epoxy resin to the mixture B, stir for 13 minutes, and keep it at a constant temperature for 2 hours to obtain a mixture C;

[0148] S4: Mix water, enhancer and water reducer evenly, heat to 33°C to obtain mixture D, and let stand for later use;

[0149] S5: Add mixture D to mixture C while stirring. After complete addition, control the temperature at 60° C. and continue stirring for 28 minutes to obtain mixture E.

[0150] S6: Mix the loess with the mixture E and stir for 1.3 h. The temperature is controlled at 55°C and the rotation speed is 180 rpm to obtain the mixed soil. The mixed soil is compacted. The compaction degree of the compacted mixed soil is 93%;

[0151] S7: Cover with a film and cure the compacted mixed soil for 7 days to obtain a finished product.

[0152] Effect evaluation

[0153] The finished materials for the silt dam prepared in Example 1, Example 2, Example 3, Example 4, Example 5, Comparative Example 1 and Comparative Example 2 were respectively obtained for testing, and each finished material was tested with reference to JTJ057 Testing Procedure for Inorganic Binder Stabilized Materials for Highway Engineering, and an unconfined compressive strength test was performed. A water stability performance test was performed according to the determination method of the water stability coefficient of rock in rock mechanics, and the test results were recorded as shown in the following table:

[0154] Compressive strength MPa Water stability coefficient% Example 1 5.8 87 Example 2 5.6 86 Example 3 5.9 88 Example 4 5.4 79 Example 5 6.1 88 Comparative Example 1 4.3 67 Comparative Example 2 2.7 72

[0155] According to the test results, the materials and preparation methods of the safe adaptive silt dam provided by the present invention have better performance in compressive strength and water stability coefficient. By comparing the values ​​of compressive strength and water stability coefficient of each embodiment and each comparative example, it can be seen that the present invention adds PVP-VA copolymer and citrate, so that the obtained finished product has a more obvious improvement in compressive strength and water stability coefficient. From the values ​​of compressive strength and water stability coefficient of Example 1, Example 4 and Example 5 in the comparison table, it can be seen that when the prepared components are the same and the preparation method only differs in the number of curing days, the mixed soil product cured for 10 days has better compressive strength and water stability coefficient than the mixed soil products cured for 5 days and 7 days. Comparing Comparative Example 1 and Comparative Example 2, it can be seen that the mixed soil product with PVP-VA copolymer and citrate added has better compressive strength and water stability coefficient than the mixed soil product with only PVP-VA copolymer added.

[0156] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A silt dam material, characterized in that: In parts by weight, it includes the following components: Loess 80~98 parts; 20-28 parts of wood fiber; 26-38 parts of slag powder; 22~26 parts of cement; 10-16 parts of fly ash; Epoxy resin 8-16 parts; 6-8 parts of PVP-VA copolymer; 3-6 parts of citrate; Enhancer 5~9 parts; 3~5 parts of water reducing agent; 30~60 parts of water; The glass transition temperature of the PVP-VA copolymer is ≥23°C; The citrate ester includes tributyl citrate, triethyl citrate and trioctyl citrate, and the mass ratio of the tributyl citrate, triethyl citrate and trioctyl citrate is (1-4):(0.5-2):

1.

2. The silt dam material according to claim 1, characterized in that: The water reducer is one or more of a polycarboxylic acid water reducer, an aminosulfonate water reducer and a naphthalene water reducer.

3. The silt dam material according to claim 1, characterized in that: The enhancer includes one or more of sodium sulfate, potassium sulfate and calcium oxide.

4. The silt dam material according to claim 3, characterized in that: The mass ratio of the sodium sulfate, potassium sulfate and calcium oxide is (2-4):(1-3):

3.

5. The silt dam material according to claim 1, characterized in that: The cement is ordinary Portland cement or composite Portland cement.

6. A method for preparing the silt dam material according to any one of claims 1 to 5, characterized in that: The following steps are involved: a) mixing loess, wood fiber, slag powder, cement, fly ash, epoxy resin, PVP-VA copolymer, citrate, reinforcing agent, water reducing agent and water to obtain mixed soil; b) compacting the mixed soil, covering it with a film, and curing it to obtain a silt dam material.

7. The preparation method according to claim 6, characterized in that: In step a), the mixing process specifically includes: a1) mixing wood fiber, slag powder, cement and fly ash to obtain a mixture A; a2) mixing the mixture A with water to obtain a mixture B; a3) mixing the mixture B with an epoxy resin, allowing the mixture to stand, and then mixing the mixture with a PVP-VA copolymer and a citrate to obtain a mixture C; a4) mixing the mixture C with the mixture D to obtain a mixture E; the mixture D comprises a water reducing agent, a reinforcing agent and water; a5) Mixing the mixture E with loess to obtain mixed soil.

8. The preparation method according to claim 7, characterized in that: Step a2) specifically includes: Add water to the mixture A and mix at a low speed for a period of time; then continue to add water and mix at a high speed for a period of time to obtain a mixture B; The rotation speed of the low-speed mixing is 50-80 rpm, and the time is 30-40 min; the rotation speed of the high-speed mixing is 300-400 rpm, and the time is 50-65 min.

9. The preparation method according to claim 7, characterized in that: In step a3), the mixing method with the PVP-VA copolymer and the citrate is forward and reverse intermittent stirring, and the specific process includes: stirring counterclockwise for 3 to 5 minutes, standing for 1 to 2 minutes, stirring clockwise for 3 to 4 minutes, and standing for 1 to 2 minutes, and the above process is repeated several times; wherein the rotation speed of the counterclockwise stirring is 100 to 120 rpm, and the rotation speed of the clockwise stirring is 130 to 150 rpm.

10. The preparation method according to claim 6, characterized in that: In step b), the compaction degree of the mixed soil after compaction is 90-95%.