Rock similar model material for simulating water-induced weakening effect and preparation method of rock similar model
By using rock-like model materials of specific compositions, including quartz sand, barite powder, gypsum, cement, glycerin, water and gypsum retarder, and adding kaolin, the problem that rock-like model in the prior art is difficult to simulate water-induced weakening effect, and the effect of rapidly simulating the collapse process of dangerous rock mass is achieved.
Patent Information
- Application Number
- CN202411964687.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-30
- Publication Date
- 2025-05-13
AI Technical Summary
Existing rock-like model materials are difficult to quickly simulate the process of water softening, crack expansion and strength reduction in dangerous rock structure surfaces under water weakening, and cannot quickly induce collapse.
Rock-like model materials including quartz sand, barite powder, gypsum, cement, glycerin, water and gypsum retarder were used to simulate water-induced weakening effects by adjusting component proportions and adding kaolin.
The rapid softening and crack expansion of rock-like similar models under water-increasing conditions is achieved, which can quickly simulate the collapse process of dangerous rock mass, and improve the operability and authenticity of collapse-like models.
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Figure CN119977505A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of prevention and control of geological disasters of slope collapse, and in particular to a rock similarity model material for simulating water weakening effect and a preparation method of the rock similarity model. Background Art
[0002] The instability of dangerous rock mass on the slope will directly threaten the life safety of residents in front of the dangerous rock mass, the safety and normal operation of hydropower hubs, roads, railways, waterways and their corresponding structures, causing a large number of casualties and economic losses.
[0003] Collapse disasters often go through a long geological history from conception to instability. The dangerous rock mass and the bedrock break rapidly at the connection surface. This process is sudden and random, so it is difficult to capture the full process monitoring information of the actual dangerous rock mass destruction on site. Designing a collapse similarity simulation test can reproduce the entire process of damage, evolution, and destruction of the dangerous rock mass, and achieve controllable instability of the dangerous rock mass. Therefore, designing a collapse evolution similarity simulation test is the key to studying the destruction mechanism of collapse disasters and the evolution law of key indicators.
[0004] In order to ensure the repeatability and authenticity of the collapse evolution simulation test, it is necessary to make a rock similarity model with controllable physical and mechanical parameters and shape. Similarity experiments need to ensure that the physical and mechanical parameters of the rock similarity model are highly similar to those of the actual rock. The weakening of the strength of the main control structure surface of the dangerous rock mass caused by rainfall and the expansion of cracks are the key factors that induce collapse. Carrying out similar model tests to explore the evolution process of the dangerous rock mass under the effect of water weakening requires the rock similarity model to have a high softening coefficient and water absorption rate, so that the dangerous rock mass will become unstable and fall within an operable time.
[0005] The commonly used rock similarity model materials in the prior art mainly use gypsum and cement as binder materials. However, the above materials are hydraulic materials and are difficult to react with water. It is difficult to quickly simulate the process of structural surface softening of dangerous rock mass under water weakening, crack expansion and strength reduction.
[0006] Therefore, it is necessary to provide a rock-like model material that can simulate rapid collapse induced by rainfall erosion. Summary of the invention
[0007] 1. Technical issues to be resolved
[0008] In order to solve the problem that the rock similarity model materials in the prior art are difficult to quickly simulate the process of structural surface softening of dangerous rock mass under water weakening, crack expansion and strength reduction, and cannot quickly induce collapse, the present invention provides a rock similarity model material simulating the water weakening effect and a method for preparing a rock similarity model.
[0009] (II) Technical solution
[0010] In order to achieve the above object, the main technical solutions adopted by the present invention include:
[0011] In a first aspect, the present invention provides a rock-like model material for simulating water-induced weakening effects, including a rock-like material and a structural surface-like material; the rock-like material is used to prepare a bedrock-like model and a dangerous rock-like model, and the structural surface-like material is used to bond the bedrock-like model and the dangerous rock-like model;
[0012] The rock-like materials include aggregates composed of quartz sand and barite powder, gypsum, cement, glycerin, water and gypsum retarder;
[0013] The structural surface similar materials include aggregates composed of quartz sand and barite powder, gypsum, kaolin, glycerin, water and gypsum retarder.
[0014] The rock-similar model material for simulating water-weakening effect as described above, preferably, in the rock-similar material, barite powder accounts for 20-80wt% of the aggregate, the mass ratio of glycerol to water is (0.05-0.15):1, the mass ratio of aggregate to gypsum is (7-8):1, the mass ratio of cement to gypsum is (0.5-1):1, the gypsum retarder is 2-4wt‰ of the gypsum, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and cement.
[0015] The rock similar model material for simulating water weakening effect as described above, preferably, in the structural surface similar material, barite powder accounts for 40-70wt% of the aggregate, the mass ratio of glycerol to water is (0.1-0.2):1, the mass ratio of aggregate to gypsum is (7-10):1, the mass ratio of kaolin to gypsum is (2-3):1, the gypsum retarder is 2-4wt‰ of gypsum, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and kaolin.
[0016] The rock-similar model material for simulating water-induced weakening effect as described above, preferably, in the rock-similar material, the particle size of quartz sand is 40-100 mesh, the particle size of barite powder is 100-300 mesh, the gypsum is 300-500 mesh α-type high-strength gypsum, and the cement is silicate PO42.5 cement.
[0017] The rock-similar model material for simulating the water-induced weakening effect as described above, preferably, in the structural surface similar material, the particle size of quartz sand is 40-100 mesh, the particle size of barite powder is 100-300 mesh, the gypsum is 300-500 mesh α-type high-strength gypsum, and the kaolin is calcined kaolin treated with calcination, the calcination temperature is 700-800°C, the calcination time is 3-5h, and the particle size of the calcined kaolin is 3000-5000 mesh.
[0018] In a second aspect, the present invention further provides a method for preparing a rock similarity model using the above rock similarity model material, comprising the following steps:
[0019] S1: Prepare bedrock similarity model and dangerous rock similarity model respectively by using rock similar materials;
[0020] S2: The bedrock similarity model and the dangerous rock similarity model are bonded together by structural surface similarity materials, and then maintained to obtain a rock similarity model.
[0021] In the method for preparing the rock similarity model as described above, preferably, in step S1, after mixing quartz sand and barite powder, gypsum and cement are added, and then glycerin, water and gypsum retarder are added, and mixed evenly to obtain a mixed material, the mixed material is poured, and after curing, a bedrock similarity model and a dangerous rock similarity model are obtained respectively.
[0022] In the method for preparing the rock similarity model as described above, preferably, in step S1, curing is performed at 20-30° C. for 2-3 days.
[0023] In the method for preparing the rock similarity model as described above, preferably, in step S2, after mixing quartz sand, barite powder and kaolin, gypsum is added, and then glycerol, water and gypsum coagulant are added, and mixed evenly to obtain a mixed material, and the mixed material is poured at the junction of the bedrock similarity model and the dangerous rock similarity model, and is allowed to stand and cure at 20-30°C for 7-10 days to obtain a rock similarity model.
[0024] In the method for preparing the rock similarity model as described above, preferably, the rock similarity model prepared in step S2 is a toppling collapse similarity model, a falling collapse similarity model or a sliding collapse similarity model.
[0025] (III) Beneficial effects
[0026] The rock similar model material of the present invention comprises rock similar material and structural surface similar material. The rock similar material is used to prepare bedrock similar model and dangerous rock similar model, and the structural surface similar material is used to bond the bedrock similar model and the dangerous rock similar model.
[0027] The materials of the bedrock and dangerous rock similar models in the present invention are different from the structural surface similar materials. The rock similar materials include quartz sand, barite powder, gypsum, cement, glycerin, water and gypsum retarder, which can better simulate the properties of bedrock and dangerous rock. The structural surface similar materials include quartz sand, barite powder, gypsum, kaolin, glycerin, water and gypsum retarder. Kaolin has the property of swelling when exposed to water and can cooperate with other components to simulate the weakening of the main control structural surface of the dangerous rock mass caused by the weakening effect of water and the phenomenon of crack expansion inducing the collapse of the dangerous rock mass, solving the problem that the structural surface of the dangerous rock mass in the existing collapse similar model is difficult to simulate softening when exposed to water and difficult to erode rapidly when exposed to water, and providing strong support for researchers to conduct research on the mechanism of collapse disasters of dangerous rock masses on slopes and monitoring and early warning tests.
[0028] Therefore, the rock similarity model prepared by using the rock similarity model material of the present invention meets the rock mass similarity, has the density, brittle failure characteristics and hydraulic properties of rock materials, can simulate the differential weathering phenomenon of the rock mass, and quickly simulate the water-induced weakening phenomenon of the soft structural surface of the dangerous rock mass, and is suitable for indoor model test research on collapse. BRIEF DESCRIPTION OF THE DRAWINGS
[0029] Figure 1 The flowchart of the method for preparing the rock similarity model is shown in FIG.
[0030] Figure 2 The figure is a flow chart for preparing a bedrock similarity model and a dangerous rock similarity model in the present invention;
[0031] Figure 3 This is a schematic diagram of the structure of the dumped rock-like model prepared in Example 1;
[0032] Figure 4 This is a schematic diagram of the structure of the falling rock similarity model prepared in Example 2;
[0033] Figure 5 This is a schematic diagram of the structure of the landslide rock similarity model prepared in Example 3.
[0034] [Description of Reference Numerals]
[0035] 1: Bedrock; 2: Dangerous rock; 3: Structural surface. DETAILED DESCRIPTION
[0036] In order to better explain the present invention and facilitate understanding, the present invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods.
[0037] The present invention provides a rock similar model material for simulating water weakening effect, including rock similar material and structural surface similar material. The rock similar material is used to prepare bedrock similar model and dangerous rock similar model, and the structural surface similar material is used to bond the bedrock similar model and the dangerous rock similar model.
[0038] The rock-like materials include aggregates composed of quartz sand and barite powder, gypsum, cement, glycerin, water and gypsum retarder.
[0039] Similar materials in the structural surface include aggregates composed of quartz sand and barite powder, gypsum, kaolin, glycerin, water and gypsum retarder.
[0040] The materials of the bedrock and dangerous rock similar models in the present invention, that is, the rock similar materials and the structural surface similar materials have different compositions. The rock similar materials include quartz sand, barite powder, gypsum, cement, glycerin, water and gypsum retarder, which can better simulate the properties of bedrock and dangerous rock. The structural surface similar materials include quartz sand, barite powder, gypsum, kaolin, glycerin, water and gypsum retarder. Kaolin has the property of swelling when exposed to water and can cooperate with other components to simulate the weakening of the main control structural surface of the dangerous rock mass caused by the weakening effect of water and the phenomenon of crack expansion inducing the collapse of the dangerous rock mass, solving the problem that the structural surface of the dangerous rock mass in the existing collapse similar model is difficult to simulate softening when exposed to water and difficult to erode rapidly when exposed to water, and providing strong support for researchers to study the mechanism of collapse disasters of dangerous rock masses on slopes and conduct monitoring and early warning test research.
[0041] The rock similarity model prepared by using the rock similarity model material of the present invention meets the rock mass similarity, has the density, brittle failure characteristics and hydraulic properties of rock materials, can simulate the differential weathering phenomenon of the rock mass, and quickly simulate the water-induced weakening phenomenon of the weak structural surface of the dangerous rock mass, and is suitable for indoor model test research on collapse.
[0042] Preferably, in rock-similar materials, the proportion of barite powder to aggregate, that is, the weight-to-bone ratio A, is 20-80wt%, the mass ratio of glycerol to water, that is, the binder concentration B, is (0.05-0.15):1, the mass ratio of aggregate to gypsum, that is, the bone-cement ratio C, is (7-8):1, the mass ratio of cement to gypsum, that is, the mud-cement ratio D, is (0.5-1):1, the gypsum retarder is 2-4wt‰ of gypsum, preferably 3‰, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and cement, preferably 15%.
[0043] Among rock-similar materials, quartz sand, as one of the main aggregates, has high hardness and wear resistance, can provide structural support, increase the hardness of the material, and help improve the overall strength and stability of the rock-similar model.
[0044] Barite powder has high density and good stability. It can increase the density of the material and make the rock-like model closer to the density of the actual rock. In rock-like materials, the weight-to-bone ratio is maintained at 20-80wt%, which can make the density and mechanical strength of bedrock and dangerous rock-like models closer to real rocks. Too low a weight-to-bone ratio will reduce the density of the material and fail to simulate high-density rocks. At the same time, the hardness and wear resistance of the material will also decrease. Although a high weight-to-bone ratio can increase the density of the material, it may cause the mixture to be too dense, with poor fluidity and difficult to pour evenly. In addition, too much barite powder may also reduce the overall strength and toughness of the material.
[0045] Gypsum is easy to hydrate and solidifies quickly. As a fast-setting binder, it can provide early strength and stiffness, allowing rock-like models to be quickly formed. The bone-cement ratio is maintained at (7-8):1, which can ensure the balance between aggregate and gypsum so that the rock-like model can achieve the required physical properties. When the bone-cement ratio is too high, that is, the aggregate ratio is too high, the binder may not be enough to fully wrap and bond all aggregate particles, resulting in a decrease in the overall strength and stiffness of the material, and cracks and fractures are prone to occur. In addition, too much aggregate will make the mixture too dry and rough, and the fluidity will deteriorate, making it difficult to mix and pour evenly. During the pouring process, voids, stratification or unevenness may occur, resulting in an insufficiently dense internal structure of the material and increased porosity. When the bone-cement ratio is too low, too much gypsum will cause the material to become more brittle, the crack resistance will decrease, and cracks will easily occur. It will also reduce the overall density of the material and cannot effectively simulate high-density rocks.
[0046] Cement can generate compounds such as calcium-silicon hydrates through hydration reactions. These compounds gradually harden over time, which can improve the strength and durability of the material and provide long-term strength and durability. The mud-paste ratio needs to be maintained at (0.5-1):1. Too large a mud-paste ratio will lead to longer curing time, reduced early strength of the material, and increased shrinkage cracks. Too small a mud-paste ratio will increase the brittleness of the material and reduce its density.
[0047] Glycerin has hygroscopicity and moisture retention, which helps to keep the mixture moist, facilitates subsequent pouring, increases the fluidity of the mixture, reduces the rate of water evaporation, and enhances the bonding force. The binder concentration is (0.05-0.15): 1. If the binder concentration is too high, the excessive glycerol content will increase the viscosity of the mixture, making it difficult to stir and pour evenly. Its poor fluidity may also cause the material to form cavities or bubbles in the mold, thereby affecting the uniformity and integrity of the model. In addition, excessive glycerol content may also prolong the curing time, causing uneven evaporation of water inside the material, cracks or deformation. If the binder concentration is too high, the mixture will lack fluidity, making it difficult to stir and pour evenly. During the pouring process, stratification or unevenness is likely to occur, affecting the uniformity and density of the model. In addition, insufficient glycerol may also cause the internal structure of the material to be not dense enough, increase porosity, and reduce its mechanical properties and durability.
[0048] Water acts as a solvent, enabling the other ingredients to be mixed evenly and participating in the hydration reaction of cement and gypsum.
[0049] The gypsum retarder can delay the setting time of the gypsum so that there is enough time for the pouring process and avoids the mixture from hardening prematurely before the mold is completely filled. Further, the gypsum retarder of the present invention can be citric acid, borax, etc.
[0050] Further preferably, among the rock-similar materials, the particle size of quartz sand is 40-100 mesh, the particle size of barite powder is 100-300 mesh, the gypsum is 300-500 mesh, preferably 400m mesh α-type high-strength gypsum, and the cement is silicate PO42.5 cement.
[0051] Preferably, in the structural surface similar material, the proportion of barite powder to aggregate, i.e., the weight-bone ratio A, is 40-70wt%, the mass ratio of glycerol to water, i.e., the concentration of binder B is (0.1-0.2): 1, the mass ratio of aggregate to gypsum, i.e., the bone-cement ratio C is (7-10): 1, the mass ratio of kaolin to gypsum, i.e., the soil-paste ratio E is (2-3): 1, the gypsum retarder is 2-4wt‰ of gypsum, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and kaolin. With the increase of the soil-paste ratio, the strength indicators of the structural surface similar materials, including compressive strength, tensile strength and elastic modulus, will decrease. When the addition amount of kaolin is greater than the soil-paste ratio upper limit defined above, the structural surface similar materials will undergo a more obvious strain softening phenomenon, the water absorption rate and water softening of the material will increase, and the structural surface similar materials will also be unsuitable for simulating water softening.
[0052] The functions of quartz sand, barite powder, gypsum, glycerin, water and gypsum retarder in the structural surface similar materials are the same as the functions of each component in the rock similar materials, and will not be repeated here.
[0053] Among the materials with similar structural surfaces, kaolin has the property of absorbing water and swelling, and can work synergistically with other components to simulate the phenomenon of weakening of the main controlling structural surface of the dangerous rock mass due to the water-induced weakening effect and the collapse of the dangerous rock mass induced by crack expansion, thereby solving the problem that the structural surface of the dangerous rock mass in the existing collapse similarity model is difficult to simulate the softening when exposed to water and the rapid erosion when exposed to water.
[0054] Further preferably, among the materials with similar structural surfaces, the particle size of quartz sand is 40-100 mesh, the particle size of barite powder is 100-300 mesh, the gypsum is 300-500 mesh α-type high-strength gypsum, and more preferably 400 mesh α-type high-strength gypsum, and the kaolin is calcined kaolin that has been calcined, the calcination temperature is 700-800°C, and the calcination time is 3-5h. The particle size of the kaolin after calcination is preferably 3000-5000 mesh, and more preferably 4000 mesh. The calcined kaolin in this particle size range has a larger specific surface area, and its adsorption, dispersibility and reactivity are more superior.
[0055] Kaolin contains more hydroxyl groups and has good water absorption performance. After calcination, it is generally believed that the water absorption capacity of kaolin will decrease significantly. However, the present invention can change the microstructure of kaolin after calcining kaolin at 700-800°C for 3-5 hours to form a complex pore network structure. These pores can serve as channels for water penetration and achieve rapid absorption of water through capillary action. Therefore, the pore structure formed in the kaolin treated with high temperature calcination in the present invention helps to distribute water more quickly to the entire structural surface of similar materials, thereby accelerating the progress of softening when exposed to water.
[0056] In addition, the surface of calcined kaolin particles becomes rougher. When encountering water, water quickly penetrates into the interior of the particles through the rough surface and pore network. The rough surface provides more paths for water molecules to enter. Moreover, as water penetrates, liquid bridges gradually form in the gaps between particles. The liquid bridges can not only fill the gaps, but also play a lubricating role, reducing the friction between particles, making it easier for particles to slide or separate when encountering water when mixed in materials with similar structural surfaces, thereby promoting the softening of the overall material.
[0057] Although uncalcined kaolin has certain water absorption properties, it does not form a complex pore network and cannot form liquid bridges when it comes into contact with water. Therefore, its softening performance when exposed to water is not as good as that of calcined kaolin.
[0058] Second, as Figure 1 As shown, the present invention also provides a method for preparing a rock similarity model using the above-mentioned rock similarity model material, comprising the following steps:
[0059] S1: Prepare bedrock similarity model and dangerous rock similarity model respectively using rock similar materials.
[0060] S2: The bedrock similarity model and the dangerous rock similarity model are bonded together by structural surface similarity materials, and then maintained to obtain a rock similarity model.
[0061] Preferably, refer to Figure 2 In the above step S1, the raw materials are weighed according to the model volume and ratio, and the quartz sand and barite powder are mixed and stirred, and then gypsum and cement are added as binders, and then glycerin, water and gypsum retarder are added, and mixed evenly to obtain a mixed material, and the mixed material is poured into the mold, compacted, and vibrated until no bubbles overflow, and demolded after curing to obtain a bedrock similar model and a dangerous rock similar model. Further preferably, in step S1, the curing can be carried out at 20-30°C for 2-3 days.
[0062] Preferably, in the above step S2, after the quartz sand, barite powder and kaolin are mixed and stirred evenly, gypsum is added as a binder, and then glycerin, water and gypsum coagulant are added and mixed evenly to obtain a mixed material, and the mixed material is poured at the junction of the bedrock similar model and the dangerous rock similar model to bond the bedrock and the dangerous rock body, and is left to stand and cure at 20-30°C for 7-10 days to obtain a rock similar model.
[0063] The rock similarity model prepared in the above step S2 can be any one of a toppling collapse similarity model, a falling collapse similarity model or a sliding collapse similarity model.
[0064] In order to further clarify the scheme of the present invention and its technical advancement, the following is a description in conjunction with specific embodiments and technical effects.
[0065] Example 1
[0066] This embodiment provides a method for preparing a rock similarity model. The total volume of the bedrock similarity model and the dangerous rock similarity model in this embodiment is 0.051m 3 , a total of 127.5kg of rock-like materials are needed. To ensure sufficient rock-like materials, the material loss coefficient is 8%, and the total mass of rock-like materials actually weighed is 137.7kg. The volume of the structural surface is 0.0006m 3 , the mass of the material with similar structure surface is 0.126kg. In order to ensure the sufficient amount of material with similar structure surface, the material loss coefficient is 30%, and the total mass of the raw materials actually weighed is 0.164kg. The preparation method specifically comprises the following steps:
[0067] S1: According to A=0.7, B=0.15, C=8, D=0.5, weigh 29.76kg of quartz sand, 69.44kg of barite powder, 12.40kg of gypsum, 6.20kg of cement, 2.51kg of glycerine, 16.74kg of water, and 37.2g of gypsum retarder. Mix the quartz sand and barite powder and add gypsum and cement, then add glycerine, water, and gypsum retarder, then pour into the mold, vibrate and compact, and remove the mold after curing for 3 days to obtain the dangerous rock mass model and bedrock model respectively.
[0068] S2: According to A=0.7, B=0.2, C=8, E=2, weigh 31.2g of quartz sand, 72.8g of barite powder, 13g of gypsum, 26g of kaolin, 3.51g of glycerine, 17.55g of water, and 0.04g of gypsum retarder. Mix the quartz sand, barite powder and kaolin, add gypsum, and then add glycerine, water and gypsum retarder to obtain a structural surface similar material. Pour the structural surface similar material at the junction of the bedrock similar model and the dangerous rock similar model, bond the bedrock and the dangerous rock mass, and let it stand for 10 days to obtain the following: Figure 3 The dumping rock similarity model shown is the collapse similarity experimental model.
[0069] Example 2
[0070] This embodiment provides a method for preparing a rock similarity model. The total volume of the bedrock similarity model and the dangerous rock similarity model in this embodiment is 0.045m 3 , a total of 112.5kg of rock-like materials are needed. To ensure sufficient rock-like materials, the material loss coefficient is 8%, and the total mass of rock-like materials actually weighed is 121.5kg. The volume of the structural surface is 0.00053m 3 , the mass of the material with similar structure surface is 0.112kg. In order to ensure the sufficient amount of material with similar structure surface, the material loss coefficient is 30%, and the total mass of the raw materials actually weighed is 0.145kg. The preparation method specifically comprises the following steps:
[0071] S1: According to A=0.4, B=0.15, C=7, D=0.5, weigh 51.66kg of quartz sand, 34.44kg of barite powder, 12.30kg of gypsum, 6.15kg of cement, 2.21kg of glycerine, 14.76kg of water, and 37g of gypsum retarder. Mix the quartz sand and barite powder and add gypsum and cement, then add glycerine, water, and gypsum retarder, then pour into the mold, vibrate and compact, and remove the mold after curing for 2 days to obtain the dangerous rock mass model and bedrock model respectively.
[0072] S2: According to A=0.4, B=0.2, C=7, E=1, weigh 58.38g of quartz sand, 38.92g of barite powder, 13.9g of gypsum, 13.9g of kaolin, 3.36g of glycerin, 16.68g of water, and 0.04g of gypsum retarder. Mix the quartz sand, barite powder and kaolin, add gypsum, and then add glycerin, water, and gypsum retarder to obtain a structural surface similar material. Pour the structural surface similar material at the junction of the bedrock similar model and the dangerous rock similar model, bond the bedrock and the dangerous rock mass, and let it stand for 7 days to obtain the following Figure 4 Similar model of falling rock shown.
[0073] Example 3
[0074] This embodiment provides a method for preparing a rock similarity model. The total volume of the bedrock similarity model and the dangerous rock similarity model in this embodiment is 0.051m 3 , a total of 127.5kg of rock-like materials are needed. To ensure sufficient rock-like materials, the material loss coefficient is 8%, and the total mass of rock-like materials actually weighed is 137.7kg. The volume of the structural surface is 0.0006m 3 , the mass of the material with similar structure surface is 0.126kg. In order to ensure the sufficient amount of material with similar structure surface, the material loss coefficient is 30%, and the total mass of the raw materials actually weighed is 0.164kg. The preparation method specifically comprises the following steps:
[0075] S1: According to A=0.6, B=0.15, C=7, D=0.2, weigh 60.06kg of quartz sand, 40.04kg of barite powder, 14.30kg of gypsum, 2.86kg of cement, 3.43kg of glycerine, 17.16kg of water, and 42.9g of gypsum retarder. Mix the quartz sand and barite powder and add gypsum and cement, then add glycerine, water, and gypsum retarder, then pour into the mold, vibrate and compact, and remove the mold after curing for 3 days to obtain the dangerous rock mass model and bedrock model respectively.
[0076] S2: According to A=0.2, B=0.2, C=5, E=3, weigh 65.2g of quartz sand, 16.3g of barite, 16.3g of gypsum, 48.9g of kaolin, 2.93g of glycerin, 14.67g of water, and 0.05g of gypsum retarder. Mix the quartz sand, barite powder and kaolin, add gypsum, and then add glycerin, water, and gypsum retarder to obtain a structural surface similar material. Pour the structural surface similar material at the junction of the bedrock similar model and the dangerous rock similar model, bond the bedrock and the dangerous rock mass, and let it stand for 9 days to obtain the following Figure 5 The sliding rock similarity model shown is the collapse similarity experimental model.
[0077] Comparative Example 1
[0078] This comparative example provides a method for preparing a rock-similar model, which is different from Example 1 in that the kaolin is not calcined.
[0079] Rock physical and mechanical tests were performed on the rock similar models prepared in the above embodiments and comparative examples to obtain the physical and mechanical parameters of the rock similar materials and structural surface similar materials shown in Table 1.
[0080] Table 1 Statistical table of physical and mechanical parameters of similar materials in the embodiments and comparative examples
[0081]
[0082]
[0083] It can be seen from Table 1 that the softening coefficients of the rock-like materials of Examples 1-3 are in the range of 0.85-0.93, showing high water resistance like cement, and the relevant properties of the rock-like materials and structural surface-like materials of Examples 1-3 are close to the real rock properties, and the softening coefficients of the structural surface-like materials are in the range of 0.40-0.55, showing significant softening characteristics when exposed to water, because calcined kaolin is mixed therein. Uncalcined kaolin is used in Comparative Example 1. Although the density, compressive strength, tensile strength, cohesion, internal friction angle and elastic modulus of the structural surface-like materials are close to those of Example 1, the softening coefficient is 0.76, which is much higher than the softening coefficients of the structural surface-like materials in Examples 1-3. Therefore, if the calcined kaolin is replaced with uncalcined kaolin, it will be difficult to simulate the softening phenomenon when exposed to water. Therefore, the present invention overcomes the problem that the structural surface of dangerous rock mass in collapse similarity model is difficult to simulate the softening of dangerous rock mass when it encounters water. The present invention can simulate the water-induced weakening phenomenon of the weak structural surface of dangerous rock mass, simulate the differential weathering phenomenon of rock mass, and solve the problem that the collapse similarity model is difficult to be rapidly eroded by water, thus providing favorable support for researchers to conduct research on the mechanism of collapse disaster of dangerous rock mass on slope and monitoring and early warning experiments.
[0084] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.
Claims
1. A rock-like model material for simulating water-induced weakening effects, characterized in that: It includes rock-like materials and structural surface-like materials; the rock-like materials are used to prepare bedrock-like models and dangerous rock-like models, and the structural surface-like materials are used to bond the bedrock-like models and dangerous rock-like models; The rock-like materials include aggregates composed of quartz sand and barite powder, gypsum, cement, glycerin, water and gypsum retarder; The structural surface similar materials include aggregates composed of quartz sand and barite powder, gypsum, kaolin, glycerin, water and gypsum retarder.
2. The rock-like model material for simulating water weakening effect according to claim 1, characterized in that: In the rock-similar material, barite powder accounts for 20-80wt% of the aggregate, the mass ratio of glycerol to water is (0.05-0.15):1, the mass ratio of aggregate to gypsum is (7-8):1, the mass ratio of cement to gypsum is (0.5-1):1, the gypsum retarder is 2-4wt‰ of the gypsum, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and cement.
3. The rock-like model material for simulating water weakening effect according to claim 1, characterized in that: In the structural surface similar material, barite powder accounts for 40-70wt% of the aggregate, the mass ratio of glycerol to water is (0.1-0.2):1, the mass ratio of aggregate to gypsum is (7-10):1, the mass ratio of kaolin to gypsum is (2-3):1, the gypsum retarder is 2-4wt‰ of gypsum, and water accounts for 12-18wt% of the total mass of aggregate, gypsum and kaolin.
4. The rock-like model material for simulating water weakening effect according to claim 1, characterized in that: Among the rock-similar materials, the particle size of quartz sand is 40-100 meshes, the particle size of barite powder is 100-300 meshes, the gypsum is 300-500 mesh α-type high-strength gypsum, and the cement is silicate PO42.5 cement.
5. The rock-like model material for simulating water weakening effect according to claim 1, characterized in that: Among the structural surface similar materials, the particle size of quartz sand is 40-100 mesh, the particle size of barite powder is 100-300 mesh, the gypsum is 300-500 mesh α-type high-strength gypsum, and the kaolin is calcined kaolin treated by calcination. The calcination temperature is 700-800°C, the calcination time is 3-5h, and the particle size of the calcined kaolin is 3000-5000 mesh.
6. A method for preparing a rock similarity model using the rock similarity model material according to any one of claims 1 to 5, characterized in that: The steps include: S1: Prepare bedrock similarity model and dangerous rock similarity model respectively by using rock similarity materials; S2: The bedrock similarity model and the dangerous rock similarity model are bonded together by structural surface similarity materials, and then maintained to obtain a rock similarity model.
7. The method for preparing a rock similarity model according to claim 6, characterized in that: In step S1, after quartz sand and barite powder are mixed and stirred evenly, gypsum and cement are added, and then glycerin, water and gypsum retarder are added, and mixed evenly to obtain a mixed material, and the mixed material is poured, and after curing, a bedrock similarity model and a dangerous rock similarity model are obtained respectively.
8. The method for preparing a rock similarity model according to claim 7, characterized in that: In step S1, the mixture is cured at 20-30°C for 2-3 days.
9. The method for preparing a rock similarity model according to claim 6, characterized in that: In step S2, after quartz sand, barite powder and kaolin are mixed and stirred evenly, gypsum is added, and then glycerin, water and gypsum coagulant are added, and mixed evenly to obtain a mixed material, and the mixed material is poured at the junction of the bedrock similarity model and the dangerous rock similarity model, and is allowed to stand and cure at 20-30°C for 7-10 days to obtain a rock similarity model.
10. The method for preparing a rock similarity model according to claim 6, characterized in that: The rock similarity model prepared in step S2 is a toppling collapse similarity model, a falling collapse similarity model or a sliding collapse similarity model.