Eu 3+ Application of highly active β-Ca2SiO4 in grouting slurry diffusion tracing

Abstract

The application relates to the technical field of grouting, in particular to Eu 3+ Application of doped high-activity beta-Ca2SiO4 in grouting slurry diffusion tracing. 3+ The doped high-activity beta-Ca2SiO4 endows the beta-Ca2SiO4 with excellent luminescent performance without changing the original performance of the beta-Ca2SiO4, and the excellent luminescent performance can conveniently, directly and quickly trace the penetration depth and flow condition of the slurry. The material has physical and chemical properties similar to those of the actual engineering application material, and is expected to be used as a candidate material for verifying the accuracy of numerical simulation.

Description

Technical Field

[0001] This invention relates to the field of grouting technology, and in particular to Eu 3+ Application of highly active doped β-Ca2SiO4 in grout diffusion tracing. Background Technology

[0002] During grouting, a grout made of cement or other materials is injected into the object to be repaired, filling the cracks. Cracks are mostly randomly distributed, making it nearly impossible to accurately define the length, width, and direction of each crack. Furthermore, unlike water, grout is typically viscous and behaves as a non-Newtonian fluid. For these reasons, the flow of the grout after grouting is highly complex, making it difficult to analyze the penetration depth and flow of the grout within the cracks during the grouting process, thus hindering the evaluation of the grouting's effectiveness.

[0003] To characterize the diffusion of grout, scholars from various countries and regions have conducted extensive research on theoretical methods for grout diffusion analysis. In recent years, various numerical methods have been used to simulate the penetration depth of grout in the matrix, but there is still no simple way to determine the accuracy of numerical models in practical applications. In actual engineering projects, there are many ways to characterize the flow of grout; however, existing tracking methods require complex testing instruments or long testing cycles, making it still very laborious to track the distribution of grouting materials. Summary of the Invention

[0004] To address the aforementioned problems, the objective of this invention is to provide Eu 3+ Application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing. This invention utilizes Eu... 3+ Doping with highly active β-Ca₂SiO₄ imparts excellent luminescence properties to β-Ca₂SiO₄ without altering its original properties. This superior luminescence characteristic allows for convenient, intuitive, and rapid tracking of the penetration depth and flow characteristics of slurries. The material exhibits physicochemical properties similar to those of materials used in practical engineering applications, making it a promising candidate material for verifying the accuracy of numerical simulations.

[0005] In this invention, dicalcium silicate (Ca2SiO4) is one of the main minerals in cement and has a variety of crystal forms. Among them, the β phase Ca2SiO4 has characteristics that are completely different from traditional cement. Its production requires less raw materials and energy than traditional cement. It does not produce harmful gases during its production process and only emits a small amount of CO2. Its excellent physical and chemical properties make it show great potential in the field of inorganic grouting materials.

[0006] β-Ca₂SiO₄, due to its wide band gap, low phonon energy, and stable physical, chemical, and thermal properties, has been proven to be a suitable calcium silicate matrix material for lanthanide luminescent ions and is widely used in phosphors and scintillators. Therefore, modifying β-Ca₂SiO₄ with excellent hydration activity through rare earth ion doping, and utilizing the luminescent properties of rare earth ions, endows β-Ca₂SiO₄ with indicative capabilities during grouting. This allows for more intuitive tracking of grout penetration depth and flow patterns, and holds promise as a candidate material for verifying and improving the accuracy of numerical simulations.

[0007] The objective of this invention can be achieved through the following technical solutions:

[0008] This invention provides an Eu 3+ The application of highly active doped β-Ca2SiO4 in grouting slurry diffusion tracing includes the following steps (1) and (2), or (1) and (3):

[0009] (1) Pre-processed Eu 3+ Highly active β-Ca2SiO4 is added to water, and if necessary, water-reducing agents, suspension stabilizers and other additives can be added. After mixing, the grouting slurry is obtained.

[0010] (2) The grouting slurry prepared in step (1) is injected into the simulated sample according to the conventional grouting operation. After curing, the simulated sample is cut open and placed under a UV lamp to observe the slurry diffusion.

[0011] (3) The grouting slurry prepared in step (1) is injected into the on-site sample according to the conventional grouting operation. After curing, the sample is cut open and placed under ultraviolet light to observe the slurry diffusion.

[0012] In one embodiment of the present invention, the Eu 3+ The general chemical formula of doped highly active β-Ca₂SiO₄ is (Ca 2- x Eu x (Si) 0.96 B 0.04 )O4, where 0.02≤x≤0.05.

[0013] In one embodiment of the present invention, the conventional grouting operation includes atmospheric pressure grouting and pressure grouting.

[0014] In one embodiment of the present invention, the Eu 3+ The preparation method of doped highly active β-Ca2SiO4 includes the following steps:

[0015] (a) The Ca-containing compound, the Si-containing compound, the Eu-containing compound and the B-containing compound were mixed evenly according to the stoichiometric ratio to obtain a mixed powder;

[0016] (b) The mixed powder obtained in step (a) is pretreated and then subjected to high-temperature calcination to obtain Eu. 3+ Highly active β-Ca2SiO4 doped.

[0017] In one embodiment of the present invention, in step (a), the Ca-containing compound is selected from one or both of calcium oxide and calcium carbonate;

[0018] The Si-containing compound is selected from one or both of silicon oxide and fumed silicon dioxide.

[0019] The Eu-containing compound is selected from one or both of europium oxide and europium nitrate;

[0020] The B-containing compound acts as a crystal stabilizer during the synthesis process (β-Ca2SiO4 is metastable and exists mostly as γ-Ca2SiO4 at room temperature. However, γ-Ca2SiO4 has extremely low hydration activity, so a crystal stabilizer needs to be added during production to prevent the formation of γ-Ca2SiO4 in the product), and is selected from one or both of boron oxide and boric acid.

[0021] In one embodiment of the invention, in step (b), the pretreatment involves pressing the mixed powder into a cake shape.

[0022] In one embodiment of the present invention, in step (b), the high-temperature calcination process is carried out in an air atmosphere at a temperature of 1400°C-1500°C for 2-4 hours.

[0023] In one embodiment of the invention, in step (b), the post-processing is to allow the material to cool naturally to room temperature.

[0024] In one embodiment of the present invention, the pretreatment in step (1) is mechanical crushing followed by grinding;

[0025] The Eu 3+ The particle size of the doped highly active β-Ca2SiO4 is less than 10 μm.

[0026] In one embodiment of the present invention, in step (2), the temperature during the curing process is 19℃-21℃, the humidity is 89%-91%, and the time is 72h.

[0027] The Eu of the present invention 3+ Highly active doped β-Ca2SiO4 exhibits excellent luminescence properties, enabling convenient, intuitive, and rapid tracking of the penetration depth and flow of slurries. It can serve as a candidate material for verifying the accuracy of numerical simulations.

[0028] Compared with the prior art, the present invention has the following beneficial effects:

[0029] Eu used in this invention 3+ The preparation process of doped highly active β-Ca2SiO4 is simple, the raw materials and energy required for production are low, no harmful gases are generated during the production process, there is no pollutant emission, only a small amount of CO2 is emitted, and the material itself is non-toxic, harmless and environmentally friendly.

[0030] Eu used in this invention 3+ The hydration and mechanical properties of doped highly active β-Ca2SiO4 are similar to those of materials used in practical engineering applications. It also has stable optical properties and emits strong red light under ultraviolet light excitation. The luminescence intensity does not decay with hydration time.

[0031] The Eu of the present invention 3+ In the application of highly active doped β-Ca2SiO4 in grout slurry diffusion tracing, Eu 3+ Highly active β-Ca2SiO4 can effectively simulate the diffusion of slurries in practical engineering applications. Furthermore, by utilizing the fluorescence properties of the slurry, the diffusion process can be tracked intuitively and quickly, enabling visualization of the slurry diffusion. This process is faster and more accurate, and it is expected to serve as a candidate material for verifying the accuracy of numerical simulations. Attached Figure Description

[0032] Figure 1 Eu obtained from the preparation of Example 1 3+ X-ray diffraction pattern of highly active β-Ca2SiO4 powder;

[0033] Figure 2 Eu obtained from the preparation of Example 1 3+ Figure showing the particle size analysis results of doped highly active β-Ca2SiO4 powder;

[0034] Figure 3 Eu obtained from the preparation of Example 1 3+ Excitation spectrum of highly active β-Ca2SiO4 powder;

[0035] Figure 4 Eu obtained from the preparation of Example 1 3+ Emission spectrum of highly active β-Ca2SiO4 powder;

[0036] Figure 5 Eu obtained from the preparation of Example 1 3+ Physical images of doped highly active β-Ca2SiO4 powder; left side under sunlight, right side under 395nm ultraviolet light;

[0037] Figure 6 Eu prepared in Example 2 3+A top view of highly active β-Ca2SiO4 applied to grout diffusion tracing; the left side is under 395nm ultraviolet light, and the right side is under sunlight;

[0038] Figure 7 Eu prepared in Example 2 3+ Cross-sectional view of highly active β-Ca2SiO4 used for diffusion tracing in grouting slurry; left side under 395nm ultraviolet light, right side under sunlight;

[0039] Figure 8 Eu prepared in Example 3 3+ A top view of highly active β-Ca2SiO4 applied to grout diffusion tracing; the left side is under 395nm ultraviolet light, and the right side is under sunlight;

[0040] Figure 9 Eu prepared in Example 3 3+ Cross-sectional view of highly active β-Ca2SiO4 used for grout diffusion tracing; left side under 395nm UV light, right side under sunlight. Detailed Implementation

[0041] This invention provides an Eu 3+ The application of highly active doped β-Ca2SiO4 in grouting slurry diffusion tracing includes the following steps (1) and (2), or (1) and (3):

[0042] (1) Pre-processed Eu 3+ Highly active β-Ca2SiO4 is added to water, and if necessary, water-reducing agents, suspension stabilizers and other additives can be added. After mixing, the grouting slurry is obtained.

[0043] (2) The slurry prepared in step (1) is injected into the simulated sample according to the conventional grouting operation. After curing, the simulated sample is cut open and placed under a UV lamp to observe the slurry diffusion.

[0044] (3) The grout prepared in step (1) is injected into the on-site sample according to the conventional grouting operation. After curing, the sample is cut open and placed under ultraviolet light to observe the grout diffusion.

[0045] In one embodiment of the present invention, the Eu 3+ The general chemical formula of doped highly active β-Ca₂SiO₄ is (Ca 2- x Eu x (Si) 0.96 B 0.04 )O4, where 0.02≤x≤0.05.

[0046] In one embodiment of the present invention, the conventional grouting operation includes atmospheric pressure grouting and pressure grouting.

[0047] In one embodiment of the present invention, the Eu 3+ The preparation method of doped highly active β-Ca2SiO4 includes the following steps:

[0048] (a) The Ca-containing compound, the Si-containing compound, the Eu-containing compound and the B-containing compound were mixed in stoichiometric ratio and then ground in a mortar mill to obtain a mixed powder;

[0049] (b) The mixed powder obtained in step (a) is pretreated and then subjected to high-temperature calcination to obtain Eu. 3+ Highly active β-Ca2SiO4 doped.

[0050] In one embodiment of the present invention, in step (a), the Ca-containing compound is selected from one or both of calcium oxide and calcium carbonate;

[0051] The Si-containing compound is selected from one or both of silicon oxide and fumed silicon dioxide.

[0052] The Eu-containing compound is selected from one or both of europium oxide and europium nitrate;

[0053] The B-containing compound acts as a crystal stabilizer during the synthesis process and is selected from one or both of boron oxide and boric acid.

[0054] In one embodiment of the invention, in step (b), the pretreatment involves pressing the mixed powder into a cake shape.

[0055] In one embodiment of the present invention, in step (b), the high-temperature calcination process is carried out in an air atmosphere at a temperature of 1400°C-1500°C for 2-4 hours.

[0056] In one embodiment of the invention, in step (b), the post-processing is to allow the material to cool naturally to room temperature.

[0057] In one embodiment of the present invention, the pretreatment in step (1) is mechanical crushing followed by grinding;

[0058] The Eu 3+ The particle size of the doped highly active β-Ca2SiO4 is less than 10 μm.

[0059] In one embodiment of the present invention, in step (2), the temperature during the curing process is 19℃-21℃, the humidity is 89%-91%, and the time is 72h.

[0060] The Eu of the present invention 3+Highly active doped β-Ca2SiO4 exhibits excellent luminescence properties, enabling convenient, intuitive, and rapid tracking of the penetration depth and flow of slurries. It can serve as a candidate material for verifying the accuracy of numerical simulations.

[0061] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0062] Unless otherwise specified, all reagents used in the following embodiments are commercially available reagents, and all detection methods and techniques used are conventional detection methods and techniques in the art.

[0063] Example 1

[0064] This embodiment provides an Eu 3+ Highly active doped β-Ca2SiO4 powder and its preparation method.

[0065] (1) After mixing the raw materials CaCO3, SiO2, Eu2O3 and H3BO3, put them into a mortar and pestle mill and grind them evenly at 100 rpm for 2 hours to ensure that all raw materials are fully mixed and uniform to obtain a mixed powder.

[0066] (2) The mixed powder obtained in step (1) is pressed into blocks with a diameter of 50 mm and a thickness of 2 cm under a pressure of 2 MPa. Each block weighs about 100 g and is held under pressure for 2 minutes. Then it is placed in a muffle furnace and calcined at 1450 °C in air atmosphere for 3 hours to obtain the calcined product.

[0067] (3) After the calcined product obtained in step (2) is naturally cooled to room temperature, it is mechanically crushed, then uniformly ground at 100 rpm for 2 hours using a mortar and pestle mill, and then further ground using an air jet mill to finally obtain Eu. 3+ Highly active doped β-Ca2SiO4 powder: (Ca 1.95 Eu 0.05 (Si) 0.96 B 0.04 )O4.

[0068] The (Ca) prepared in this embodiment 1.95 Eu 0.05 (Si) 0.96 B 0.04 The X-ray powder diffraction pattern of O4 is as follows: Figure 1 As shown, the intensity and position of its diffraction peaks are basically consistent with the β-Ca2SiO4 standard card, with no impurity peaks or other phases.

[0069] The (Ca) prepared in this embodiment 1.95 Eu 0.05 (Si) 0.96 B 0.04 The particle size analysis results of O4 are as follows: Figure 2As shown, the average particle size is 6.857 μm.

[0070] The (Ca) prepared in this embodiment 1.95 Eu 0.05 (Si) 0.96 B 0.04 The excitation and emission spectra of O4 monitored at room temperature are shown below. Figure 3 and Figure 4 As shown. The results indicate that (Ca 1.95 Eu 0.05 (Si) 0.96 B 0.04 The optimal excitation wavelength for O4 is 395 nm, under which strong fluorescence is produced, mainly red light with a wavelength of 703 nm.

[0071] The (Ca) prepared in this embodiment 1.95 Eu 0.05 (Si) 0.96 B 0.04 Photos of O4 taken under sunlight and 395nm ultraviolet light, as shown below. Figure 5 As shown. The results indicate that (Ca 1.95 Eu 0.05 (Si) 0.96 B 0.04 O4 is a white powder under sunlight. When irradiated with a 395nm ultraviolet lamp, the powder emits a strong red light and can maintain uniform luminescence.

[0072] Example 2

[0073] This embodiment describes a method for preparing Eu from Example 1. 3+ Application of highly active doped β-Ca2SiO4 in grout diffusion tracing.

[0074] (1) 10g of the (Ca) prepared in Example 1 1.95 Eu 0.05 (Si) 0.96 B 0.04 Add O4 to 10g of water and mix well to prepare a slurry with a water-cement ratio of 1.0;

[0075] (2) Use a standard sieve to separate sand particles with a diameter of 20-30 mesh, and add 50g of sand particles into a transparent plastic cup; in order to facilitate the later shooting of the cross-sectional view, cut the transparent plastic cup in half along the center line in advance, and then glue it together with transparent tape;

[0076] (3) Take 1 ml of the slurry prepared in step (1) and drip it at a rate of 12 drops / minute to the center of the sand particles prepared in step (2), allowing it to flow in naturally. When dripping, pay attention to the position of each drop of slurry in a circular area with a diameter of 1 cm at the center. After the slurry has completely penetrated, place the transparent plastic cup in a constant temperature and humidity chamber for three days. The curing conditions should be strictly controlled at a temperature of 20℃ (±1℃) and a humidity of 90% (±1%).

[0077] Three days later, the transparent plastic cup was removed, and top-view photos of the rim were taken under sunlight and a 395nm ultraviolet light. Then, the transparent plastic cup was placed horizontally, the transparent tape was peeled off, and the upper half of the transparent plastic cup was removed. The remaining lower half of the transparent plastic cup was smoothed of any grit with a brush, and cross-sectional views were taken under sunlight and a 395nm ultraviolet light (e.g., ...). Figure 6 and Figure 7 (As shown).

[0078] Example 3

[0079] This embodiment describes a method for preparing Eu from Example 1. 3+ Application of highly active doped β-Ca2SiO4 in grout diffusion tracing.

[0080] (1) 10g of the (Ca) prepared in Example 1 1.95 Eu 0.05 (Si) 0.96 B 0.04 Add O4 to 20g of water and mix well to prepare a slurry with a water-cement ratio of 2.0;

[0081] (2) Use a standard sieve to separate sand particles with a diameter of 20-30 mesh, and add 50g of sand particles into a transparent plastic cup; in order to facilitate the later shooting of the cross-sectional view, cut the transparent plastic cup in half along the center line in advance, and then glue it together with transparent tape;

[0082] (3) Take 1 ml of the slurry prepared in step (1) and drip it at a rate of 12 drops / minute to the center of the sand particles prepared in step (2), allowing it to flow in naturally. When dripping, pay attention to the position of each drop of slurry in a circular area with a diameter of 1 cm at the center. After the slurry has completely penetrated, place the transparent plastic cup in a constant temperature and humidity chamber for three days. The curing conditions should be strictly controlled at a temperature of 20℃ (±1℃) and a humidity of 90% (±1%).

[0083] Three days later, the transparent plastic cup was removed, and top-view photos of the rim were taken under sunlight and a 395nm ultraviolet light. Then, the transparent plastic cup was placed horizontally, the transparent tape was peeled off, and the upper half of the transparent plastic cup was removed. The remaining lower half of the transparent plastic cup was smoothed of any grit with a brush, and cross-sectional views were taken under sunlight and a 395nm ultraviolet light (e.g., ...). Figure 8 and Figure 9 (As shown).

[0084] pass Figure 6-9 It can be observed that, using Eu 3+ The fluorescence properties of doped β-Ca2SiO4 allow for rapid and intuitive observation of the diffusion of slurries with different water-cement ratios in quartz sand. Figure 6 and Figure 7 It can be seen that when the water-cement ratio is 1.0, the red light emitted by the slurry is stronger and the diffusion range on the horizontal plane is larger, but the penetration depth is lower, only 0.44 cm; when the water-cement ratio increases to 2.0, the diffusion situation is as follows. Figure 8 and Figure 9 As shown, the fluorescence effect is significantly weakened at this point, and the penetration depth increases to 0.90 cm.

[0085] The results of Examples 2 and 3 show that Eu is effective in grouting processes. 3+ The excellent fluorescence properties of doped highly active β-Ca2SiO4 provide a more intuitive way to trace the flow of the grout, making the distribution of the grout in the matrix visible.

[0086] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the interpretation of the present invention, without departing from the scope of the invention, should be within the protection scope of the present invention.

Claims

1. A Eu 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, Includes the following steps: (1) Pre-treated Eu 3+ Highly active β-Ca2SiO4 is added to water and mixed to obtain grouting slurry; (2) The grouting slurry prepared in step (1) is injected into the simulated sample or the sample to be repaired on site. After curing, it is post-treated and placed under ultraviolet light to observe the diffusion of the slurry. Among them, Eu 3+ Highly active doped β-Ca2SiO4 emits a strong red light under ultraviolet light; The Eu 3+ The general chemical formula of doped highly active β-Ca₂SiO₄ is (Ca 2-x Eu x (Si) 0.96 B 0.04 O4, where 0.02 ≤ x ≤ 0.05; The Eu 3+ The preparation method of doped highly active β-Ca2SiO4 includes the following steps: (a) The Ca-containing compound, the Si-containing compound, the Eu-containing compound and the B-containing compound are mixed evenly according to the stoichiometric ratio to obtain a mixed powder; (b) The mixed powder obtained in step (a) is pretreated and then subjected to high-temperature calcination to obtain Eu after post-treatment. 3+ Highly active β-Ca2SiO4 doping; In step (a), the B-containing compound is selected from one or both of boron oxide and boric acid, and is used as a crystal form stabilizer; In step (b), the high-temperature calcination process is carried out in an air atmosphere at a temperature of 1400℃-1500℃ for 2-4 hours.

2. The Eu according to claim 1 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, In step (a), the Ca-containing compound is selected from one or both of calcium oxide and calcium carbonate; The Si-containing compound is silicon oxide; The Eu-containing compound is selected from one or both of europium oxide and europium nitrate.

3. An Eu according to claim 1 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, In step (b), the pretreatment involves pressing the mixed powder into a cake shape.

4. An Eu according to claim 1 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, In step (b), the post-processing is to allow the air to cool to room temperature naturally.

5. An Eu according to claim 1 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, In step (1), the pretreatment involves mechanical crushing followed by grinding to obtain Eu. 3+ Highly active β-Ca2SiO4 powder is doped.

6. An Eu according to claim 5 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, Eu 3+ The particle size of the doped highly active β-Ca2SiO4 powder is less than 10 μm.

7. An Eu according to claim 1 3+ The application of highly active doped β-Ca₂SiO₄ in grout slurry diffusion tracing is characterized by, In step (2), the temperature during the curing process is 19℃-21℃, the humidity is 89%-91%, and the time is 72h.

Images