Water-rich soft interlayer sandy mudstone analogue simulation material and preparation method thereof

Abstract

The application discloses a water-rich soft interlayer sandy mudstone similar simulation material and a preparation method thereof. The sandy mudstone similar simulation material takes river sand as an aggregate, takes gypsum and kaolin as cementing materials, and takes organic bentonite, polyurethane solution and 810 glue as additives. After the river sand and the gypsum and the kaolin are cemented, the sandy mudstone similar material has good brittleness and hardness. The organic bentonite has strong hydrophilicity, is easy to have a hydration reaction, and is beneficial to improving overall compactness. The 810 glue can effectively improve the adhesion of the sandy mudstone similar material, and meets the requirements of the compressive strength and the splitting strength of the silty mudstone. The isocyanate group in the polyurethane solution reacts with water, not only produces a water absorption and expansion effect, but also enhances the brittleness and strength of the sandy mudstone material, and better restores the mechanical properties and water physical properties (expansibility, permeability and water absorption) of the water-containing soft interlayer sandy mudstone.

Description

TECHNICAL FIELD

[0001] The present application relates to a kind of rock-like materials, specifically to a kind of water-rich soft interlayer sandy mudstone similar simulation material and preparation method thereof. BACKGROUND

[0002] The soft interlayer itself is loose, soft, broken and scattered, which shows obvious discontinuity and weakness, and is prone to rheology, which has a very adverse effect on geotechnical engineering projects. The sandy mudstone in the water-containing soft interlayer of the tunnel is a kind of soft rock widely distributed in the southwest mountainous area of China, which has the characteristics of dry shrinkage and wet expansion and easy weathering. The southwest mountainous area is located in the subtropical monsoon climate, with frequent rainfall and humid environment, and the environmental humidity seriously affects the strength of the sandy mudstone, which makes it easy to produce large deformation of the tunnel rock mass in the southwest region, and the phenomenon of sudden mud gushing and water gushing frequently occurs, which seriously affects the safety of tunnel construction. In order to ensure the safety of tunnel construction and operation, it is urgent to develop similar model materials for soft rock simulation to simulate different types of tunnel rock-soil to understand the influence of engineering construction on the tunnel rock mass.

[0003] Similar material simulation test is the main method to study rock mechanics engineering and scientific problems. In recent years, scholars at home and abroad have developed many types of similar materials, including soft and hard rock composite rock similar material, deep rock similar material, limestone similar material, limestone similar material, iron crystal sand cement similar material, PSTO simulation material, low strength and low elastic modulus soft rock similar material. However, previous studies on similar simulation of sandy mudstone often only focus on the basic mechanical properties of similar materials, and pay less attention to the water properties of the materials, but in actual complex working conditions, the influence of water must be considered, and there is little research on the preparation of similar materials for sandy mudstone in water-containing soft interlayer. The existing similar material preparation method cannot be similar to the important mechanical properties and water properties of the sandy mudstone in the water-containing soft interlayer. SUMMARY

[0004] The purpose of the present application is to provide a water-rich soft interlayer sandy mudstone similar simulation material and a preparation method thereof. The similar material for simulating water-containing soft interlayer is made of river sand as aggregate, gypsum and kaolin as cementing material, and organic bentonite TY-166, polyurethane solution and 810 glue as additive. The isocyanate group in the polyurethane solution reacts with water, not only producing water absorption and swelling effect, but also enhancing the brittleness and strength of the sandy mudstone material, better balancing the mechanical properties and water properties of the similar sandy mudstone material, and solving the above problems existing in the prior art.

[0005] The purpose of the present application is achieved by the following technical solutions:

[0006] A water-rich soft interlayer sandy mudstone similar simulation material, taking river sand as aggregate, taking gypsum and kaolin as cementing material, taking organic bentonite TY-166, polyurethane solution and 810 glue as additive, the proportion of the above raw materials is as follows: river sand 40-200 parts, gypsum 20-80 parts, kaolin 40-160 parts, organic bentonite TY-166 10-40 parts, polyurethane solution 10-40 parts, 801 glue 10-21 parts.

[0007] A preparation method of the water-rich soft interlayer sandy mudstone similar simulation material, comprising the following steps:

[0008] S1, weighing raw materials: according to the mass fraction, respectively, river sand 40-200 parts, gypsum 20-80 parts, kaolin 40-160 parts, organic bentonite TY-166 10-40 parts;

[0009] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin are poured into the mixer at the same time, fully mixed and uniformly formed into a uniform solid mixture, the stirring speed is controlled to be 30-50 rad / s, and the stirring time is 5-10 min;

[0010] S3, 10-40 parts of polyurethane solution and 10-21 parts of 801 glue are poured into the uniform solid mixture in sequence, and the mixture is uniformly stirred to form a uniform mixture, the stirring speed is controlled to be 80-100 rad / s, and the stirring time is 2-5 min;

[0011] S4, the uniform mixture is poured into a mold for molding, the sample mold filled is placed into a constant temperature and humidity curing box with a temperature of 23±2 DEG C and a humidity of 95% or more for curing for 24-48 h, demolding, and then placed into a constant temperature and humidity box for curing for 7-10 d, so that the sandy mudstone similar simulation material is obtained, which can be applied in the field of tunnel surrounding rock simulation.

[0012] Compared with the prior art, the present application has the following advantages:

[0013] 1. The present invention uses river sand as aggregate, gypsum and kaolin as binders, and organic bentonite TY-166, polyurethane solution, and 810 glue as additives. The beneficial effects produced by the above raw materials include: after the river sand, gypsum, and kaolin are bonded, the sandy mudstone-like material has good brittleness and hardness; the organic bentonite TY-166 has strong hydrophilicity and is easy to undergo hydration reaction, which is beneficial to improving the overall density; the 810 glue can effectively improve the adhesion of sandy mudstone-like materials and meet the requirements of compressive strength and splitting strength of siltstone; the isocyanate group in the polyurethane solution reacts with water, not only producing a water absorption and expansion effect, but also enhancing the brittleness and strength of the sandy mudstone material, and better restoring the mechanical properties and hydraulic properties (swelling, permeability, and water absorption) of the water-containing weak interlayer sandy mudstone.

[0014] 2. The present invention can make the material reach the predetermined strength in a short time, save test time, have low cost, high production efficiency, and has wide practicality.

[0015] 3. The raw materials used in the present invention are widely available, low in price, non-toxic and harmless, the process is simple, the casting and compaction molding is convenient to operate.

[0016] 4. The sandy mudstone-like material of the present invention successfully simulates the characteristics of water-bearing weak interlayer sandy mudstone and has good plasticity and uniformity. DETAILED DESCRIPTION

[0017] The technical solution of the present invention is further described below with reference to the embodiments, but is not limited thereto. Any modification or equivalent replacement of the technical solution of the present invention that does not depart from the spirit and scope of the technical solution of the present invention should be included in the scope of protection of the present invention.

[0018] The present invention provides a water-rich, weakly intercalated sandy mudstone-like simulation material. The sandy mudstone-like simulation material uses river sand as aggregate, gypsum and kaolin as cementing materials, and organic bentonite TY-166, polyurethane solution, and 810 glue as additives. The proportions of the above raw materials, calculated by mass, are as follows: 40 to 200 parts of river sand, 20 to 80 parts of gypsum, 40 to 160 parts of kaolin, 10 to 40 parts of organic bentonite TY-166, 10 to 40 parts of polyurethane solution, and 10 to 21 parts of 801 glue, wherein:

[0019] The particle size of the river sand is 40 to 200 meshes, which is used to increase the brittleness of the material;

[0020] The particle size of the kaolin is 325-1250 mesh, which is used to improve the dense filling of the material;

[0021] The particle size of the gypsum is 2000-3000 mesh, and the gypsum hardness is 8.5mp, which is used to improve the setting time of the material and control the strength of the material;

[0022] The particle size of the organic bentonite TY-166 is 200-400 mesh, which is used to improve the compactness of the material;

[0023] The polyurethane solution is a mixed solution formed by isocyanate (MDI-50) and polyether polyol (N3O3), and the specific preparation method is as follows: isocyanate (MDI-50) and polyether polyol (N3O3) are mixed uniformly at room temperature according to a mass ratio of 1:1, which is used to improve the water absorption and swelling of the material.

[0024] A preparation method of the above-mentioned water-rich soft interlayer sandy mudstone similar simulation material, comprising the following steps:

[0025] S1, weighing the raw materials: according to the mass fraction, respectively weighing river sand 40-200 parts, gypsum 20-80 parts, kaolin 40-160 parts, and organic bentonite TY-166 10-40 parts;

[0026] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin are poured into the mixer at the same time, and are fully mixed and uniformly formed into a uniform solid mixture, the stirring speed is controlled at 30-50 rad / s, and the stirring time is 5-10 min;

[0027] S3, 10-40 parts of polyurethane solution and 10-21 parts of 801 glue are poured into the uniform solid mixture in turn, and are quickly stirred uniformly to form a uniform mixture, the stirring speed is controlled at 80-100 rad / s, and the stirring time is 2-5 min;

[0028] S4, the uniform mixture is poured into a mold for molding, the filled sample mold is put into a constant temperature and humidity curing box with a temperature of 23±2℃ and a humidity of more than 95%, and is cured for 24-48h, then is demolded and put into a constant temperature and humidity box for curing for another 7-10d, and the sandy mudstone similar simulation material is obtained, wherein: the molding method is: after the uniform mixture is poured into the mold, it is compacted, the compactness of each layer is 0.75-0.85, and then is demolded after standing.

[0029] Example 1

[0030] S1, weighing river sand 100 parts, gypsum 20 parts, kaolin 80 parts, and organic bentonite TY-166 40 parts, wherein: the particle size of the river sand is 40 mesh, the particle size of the kaolin is 325 mesh, the particle size of the quartz powder is 240 mesh, the particle size of the gypsum is 2000 mesh, and the particle size of the organic bentonite TY-166 is 300 mesh.

[0031] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin is poured into the mixer at the same time, fully mixes and mixes evenly, the stirring speed is controlled to be 50 rad / s, and the stirring time is 10 min, and a uniform solid mixture is formed.

[0032] S3, 10 parts of polyurethane solution and 20 parts of 801 glue are poured into the uniform solid mixture in sequence, and the mixture is stirred quickly and uniformly, the stirring speed is controlled to be 100 rad / s, and the stirring time is 5 min, and a uniform mixture is formed.

[0033] S4, the uniform mixture is poured into a mold for compaction, the compaction degree of each layer is 0.8, each layer is stably compacted for 2 minutes, the filled sample mold is placed in a constant temperature and humidity curing box with a temperature of 23±2 DEG C and a humidity of more than 95%, and cured for 24 hours, demolded, placed in a constant temperature and humidity box for curing for 7 days, and a sandy mudstone similar simulation material is obtained.

[0034] Example 2

[0035] S1, 100 parts of river sand, 20 parts of gypsum, 80 parts of kaolin and 40 parts of organic bentonite TY-166 are weighed, wherein the particle size of the river sand is 40 meshes, the particle size of the kaolin is 325 meshes, the particle size of the quartz powder is 240 meshes, the particle size of the gypsum is 2000 meshes, and the particle size of the organic bentonite TY-166 is 300 meshes.

[0036] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin is poured into the mixer at the same time, fully mixes and mixes evenly, the stirring speed is controlled to be 50 rad / s, and the stirring time is 10 min, and a uniform solid mixture is formed.

[0037] S3, 10 parts of polyurethane solution and 20 parts of 801 glue are poured into the uniform solid mixture in sequence, and the mixture is stirred quickly and uniformly, the stirring speed is controlled to be 100 rad / s, and the stirring time is 5 min, and a uniform mixture is formed.

[0038] S4, the uniform mixture is poured into a mold for compaction, the compaction degree of each layer is 0.8, each layer is stably compacted for 2 minutes, the filled sample mold is placed in a constant temperature and humidity curing box with a temperature of 23±2 DEG C and a humidity of more than 95%, and cured for 24 hours, demolded, placed in a constant temperature and humidity box for curing for 7 days, and a sandy mudstone similar simulation material is obtained.

[0039] Example 3

[0040] S1, 100 parts of river sand, 20 parts of gypsum, 80 parts of kaolin and 40 parts of organic bentonite TY-166 are weighed, wherein the particle size of the river sand is 40 meshes, the particle size of the kaolin is 325 meshes, the particle size of the quartz powder is 240 meshes, the particle size of the gypsum is 2000 meshes, and the particle size of the organic bentonite TY-166 is 300 meshes.

[0041] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin is poured into the mixer at the same time, fully mixes and mixes evenly, the stirring speed is controlled to be 50 rad / s, and the stirring time is 10 min, and a uniform solid mixture is formed.

[0042] S3, 20 parts of polyurethane solution and 20 parts of 801 glue are poured into the uniform solid mixture in sequence, and the mixture is quickly stirred evenly, the stirring speed is controlled to be 100 rad / s, and the stirring time is 5 min, and a uniform mixture is formed.

[0043] S4, the mixed material is poured into a mold for compaction, the compaction degree of each layer is 0.8, each layer is stably compacted for 2 minutes, the filled sample mold is placed in a constant temperature and humidity curing box with a temperature of 23±2℃ and a humidity of more than 95%, and cured for 24 hours, demolded, and placed in a constant temperature and humidity box for curing for 7 days, and a sandy mudstone similar simulation material is obtained.

[0044] Example 4

[0045] S1, 100 parts of river sand, 20 parts of gypsum, 80 parts of kaolin, and 40 parts of organic bentonite TY-166 are weighed, wherein the particle size of the river sand is 40 meshes, the particle size of the kaolin is 325 meshes, the particle size of the quartz powder is 240 meshes, the particle size of the gypsum is 2000 meshes, and the particle size of the organic bentonite TY-166 is 300 meshes.

[0046] S2, the weighed river sand, gypsum, organic bentonite TY-166, kaolin is poured into the mixer at the same time, fully mixes and mixes evenly, the stirring speed is controlled to be 50 rad / s, and the stirring time is 10 min, and a uniform solid mixture is formed.

[0047] S3, 20 parts of polyurethane solution and 20 parts of 801 glue are poured into the uniform solid mixture in sequence, and the mixture is quickly stirred evenly, the stirring speed is controlled to be 100 rad / s, and the stirring time is 5 min, and a uniform mixture is formed.

[0048] S4, the mixed material is poured into a mold for compaction, the compaction degree of each layer is 0.8, each layer is stably compacted for 2 minutes, the filled sample mold is placed in a constant temperature and humidity curing box with a temperature of 23±2℃ and a humidity of more than 95%, and cured for 24 hours, demolded, and placed in a constant temperature and humidity box for curing for 7 days, and a sandy mudstone similar simulation material is obtained.

[0049] Example 5

[0050] S1, 100 parts of river sand, 20 parts of gypsum, 80 parts of kaolin, and 40 parts of organic bentonite TY-166 are weighed, wherein the particle size of the river sand is 40 meshes, the particle size of the kaolin is 325 meshes, the particle size of the quartz powder is 240 meshes, the particle size of the gypsum is 2000 meshes, and the particle size of the organic bentonite TY-166 is 300 meshes.

[0051] S2. Pour the weighed river sand, gypsum, organic bentonite TY-166 and kaolin into the mixer at the same time, mix them thoroughly and evenly, control the stirring speed to 50 rad / s and the stirring time to 10 min to form a uniform solid mixture.

[0052] S3. Pour 30 parts of polyurethane solution and 20 parts of 801 glue into the uniform solid mixture in sequence, stir quickly and evenly, control the stirring speed to 100 rad / s, and stir for 5 minutes to form a uniform mixture.

[0053] S4. Pour the uniform mixture into the mold and compact it. The compaction degree of each layer is 0.8. Each layer is kept at steady pressure for 2 minutes. Place the filled sample mold in a constant temperature and humidity curing box at 23±2℃ and humidity above 95% for 24 hours. Remove the mold and place it in a constant temperature and humidity box for another 7 days to obtain a sandy mudstone-like simulation material.

[0054] The sandy mudstone-like simulation materials prepared in Examples 1 to 5 were made into standard specimens using standard molds and tested for parameters such as compressive strength, tensile strength, permeability, swelling, and water absorption. The results were compared with those of the water-bearing sandy mudstone material. The specific results are shown in Table 1.

[0055] Table 1 Performance parameters of Examples 1 to 5

[0056]

[0057] As shown in Table 1, the compressive strength of the sandy mudstone-like simulation materials with water-bearing weak interlayers ranges from 0.86 to 1.32 MPa, the tensile strength ranges from 0.03 to 0.012 MPa, the water absorption ranges from 4.5 to 11.3%, and the permeability coefficient ranges from 1.1×10 -5 ~7.8×10 -5 cm / s, and the expansion rate ranges from 1.2 to 4.6%. Among them, Example 2 has a high degree of similarity in mechanical properties and hydraulic properties to water-bearing sandy mudstone, indicating that this similar material can well simulate actual water-bearing mudstone interlayers. By adjusting the ratio, it can also simulate other water-rich soft rocks.

Claims

1. A similar simulation material of water-rich weak interlayer sandy mudstone, characterized in that The sandy mudstone similar simulation material uses river sand as aggregate, gypsum and kaolin as binders, and organic bentonite, polyurethane solution, and 810 glue as additives. The proportions of the above raw materials are as follows, calculated by mass: 40 to 200 parts of river sand, 20 to 80 parts of gypsum, 40 to 160 parts of kaolin, 10 to 40 parts of organic bentonite, 10 to 40 parts of polyurethane solution, and 10 to 21 parts of 801 glue.

2. The water-rich weak interlayer sandy mudstone similar simulation material according to claim 1 is characterized in that The particle size of the river sand is 40 to 200 meshes.

3. The water-rich weak interlayer sandy mudstone similar simulation material according to claim 1 is characterized in that The particle size of the kaolin is 325-1250 meshes.

4. The water-rich weak interlayer sandy mudstone similar simulation material according to claim 1 is characterized in that The particle size of the gypsum is 2000-3000 meshes, and the hardness of the gypsum is 8.5 mp.

5. The water-rich weak interlayer sandy mudstone similar simulation material according to claim 1 is characterized in that The organic bentonite is organic bentonite TY-166, and the particle size is 200-400 meshes.

6. The water-rich weak interlayer sandy mudstone similar simulation material according to claim 1 is characterized in that The polyurethane solution is a mixed solution formed by isocyanate and polyether polyol, and the mass ratio of isocyanate to polyether polyol is 1:

1.

7. A method for preparing a similar simulation material of water-rich weak intercalated sandy mudstone according to any one of claims 1 to 6, characterized in that The method comprises the following steps: S1. Weigh the raw materials: weigh 40-200 parts of river sand, 20-80 parts of gypsum, 40-160 parts of kaolin, and 10-40 parts of organic bentonite respectively according to the mass ratio; S2. Pour the weighed river sand, gypsum, organic bentonite and kaolin into a blender at the same time and mix thoroughly to form a uniform solid mixture; S3. Pour 10 to 40 parts of polyurethane solution and 10 to 21 parts of 801 glue into the uniform solid mixture in sequence, and stir quickly to form a uniform mixture; S4. Pour the uniform mixture into a mold for molding. Place the filled sample mold in a constant temperature and humidity curing box at 23±2℃ and humidity above 95% for curing for 24 to 48 hours. De-mold and place it in a constant temperature and humidity box for another 7 to 10 days to obtain a sandy mudstone-like simulation material.

8. The method for preparing a similar simulation material of water-rich weak interlayer sandy mudstone according to claim 7, characterized in that In the S2, the stirring speed is 30-50 rad / s, and the stirring time is 5-10 min; in the S3, the stirring speed is 80-100 rad / s, and the stirring time is 2-5 min.

9. The method for preparing a similar simulation material of water-rich weak interlayer sandy mudstone according to claim 7, characterized in that In said S4, the molding method is: pouring the uniform mixture into the mold and then compacting it, with the compaction degree of each layer being 0.75 to 0.85, and then demoulding after standing.

10. Use of the water-rich soft interlayer sandy mudstone similar simulation material according to any one of claims 1 to 6 in the field of tunnel surrounding rock simulation.

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