CN112174568B - Modified toughening material for well cementation - Google Patents
Modified toughening material for well cementation Download PDFInfo
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- CN112174568B CN112174568B CN202011031920.1A CN202011031920A CN112174568B CN 112174568 B CN112174568 B CN 112174568B CN 202011031920 A CN202011031920 A CN 202011031920A CN 112174568 B CN112174568 B CN 112174568B
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B40/00—Processes, in general, for influencing or modifying the properties of mortars, concrete or artificial stone compositions, e.g. their setting or hardening ability
- C04B40/0028—Aspects relating to the mixing step of the mortar preparation
- C04B40/0039—Premixtures of ingredients
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/04—Portland cements
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/02—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing hydraulic cements other than calcium sulfates
- C04B28/06—Aluminous cements
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K8/00—Compositions for drilling of boreholes or wells; Compositions for treating boreholes or wells, e.g. for completion or for remedial operations
- C09K8/42—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells
- C09K8/46—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells containing inorganic binders, e.g. Portland cement
- C09K8/467—Compositions for cementing, e.g. for cementing casings into boreholes; Compositions for plugging, e.g. for killing wells containing inorganic binders, e.g. Portland cement containing additives for specific purposes
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2201/00—Mortars, concrete or artificial stone characterised by specific physical values
- C04B2201/50—Mortars, concrete or artificial stone characterised by specific physical values for the mechanical strength
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- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- C09K2208/00—Aspects relating to compositions of drilling or well treatment fluids
- C09K2208/08—Fiber-containing well treatment fluids
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Materials Engineering (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Structural Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
The invention discloses a modified toughening material for well cementation, and relates to the technical field of well cementation materials. The modified toughening material for well cementation comprises the following raw materials in percentage by mass: 70-90% of fiber material, 5-10% of organic dispersing auxiliary agent and 5-20% of inorganic dispersing auxiliary agent; putting the fiber material and the organic dispersant into a mixing device for mixing; and (3) placing the mixed prefabricated fiber material into a ball mill, grinding for 20-30min, placing the ground prefabricated fiber material and an inorganic dispersant into a mixing device, mixing, and obtaining the modified toughening material after mixing. The invention can disperse the fiber in the gel material such as cement material, reduce the agglomeration, increase the use proportion of the fiber in the cement-based material, improve the compression strength, crack resistance, toughness and durability of cement paste and reduce the shrinkage. The pumpability of fiber cement is realized during the underground operation, the cracks of cement stone are reduced, the gas channeling and the water channeling are prevented, and the safety of well cementation operation is improved.
Description
Technical Field
The invention relates to the technical field of well cementation materials, in particular to a modified toughening material for well cementation.
Background
To enhance cementitious properties, fibers are often used in a variety of cementitious materials, including mortar, concrete, and fiber cement products, and while such randomly sized fibers may improve certain mechanical properties of concrete, the mixing and dispersion requirements are generally higher due to the possibility of "balling" or flocculation and non-uniform dispersion of the fibers.
In the well cementation industry, long fibers are not easy to pump, the difficulty of fiber mixing and dispersion limits the using amount of the fibers, in the well cementation cement, the actual adding amount of the fibers into slurry is less than 2 percent, the length of the fibers for well cementation materials is not more than 10mm, and the performance of the fibers in cement products such as mortar, concrete and the like can not be better exerted.
Disclosure of Invention
The invention aims to provide a modified toughening material for well cementation, which can disperse fibers in gel materials such as cement materials and the like, reduce agglomeration, increase the use proportion of the fibers in the cement-based materials, improve the compressive strength, the crack resistance, the toughness, the durability and reduce shrinkage of cement paste. The pumpability of fiber cement is realized during the underground operation, the cracks of cement stone are reduced, the gas channeling and the water channeling are prevented, and the safety of well cementation operation is improved.
In order to solve the problems in the prior art, the invention is realized by the following technical scheme:
a modified toughening material for well cementation is characterized in that: the composite material comprises the following raw materials in percentage by mass: 70-90% of fiber material, 5-10% of organic dispersing auxiliary agent and 5-20% of inorganic dispersing auxiliary agent; the inorganic dispersing auxiliary agent is a silicon-rich material; the organic dispersing auxiliary agent is a amylopectin substance; the modified toughening material is prepared by the following preparation method:
step A, putting the fiber material and the organic dispersant into a mixing device for mixing and stirring to mix;
step B, putting the mixed prefabricated fiber material obtained in the step A into a ball mill, and grinding for 20-30 min;
and C, putting the ground prefabricated fiber material obtained in the step B and an inorganic dispersant into a mixing device for mixing to obtain the modified toughening material.
The fiber material is one or a mixture of more of cellulose fiber and renewable fiber.
The cellulose fiber includes wood fiber such as oak, aspen, bagasse, ramie, etc.; the renewable fibers include pulp fibers derived from paper products.
The fiber length of the fiber material is 0.01-20 mm.
The inorganic dispersing auxiliary agent is one or a mixture of more of fly ash, micro silicon powder and metakaolin.
The amylopectin is potato starch and/or corn starch.
In order to solve the problems in the prior art, the invention also provides a fiber toughness well cementing material adopting the modified toughening material. The fiber can be dispersed in gel materials such as cement materials and the like, the agglomeration is reduced, the use proportion of the fiber in the cement-based materials is increased, the compressive strength, the crack resistance, the toughness and the durability of cement paste are improved, and the shrinkage is reduced. The pumpability of fiber cement is realized during the underground operation, the cracks of cement stone are reduced, the gas channeling and the water channeling are prevented, and the safety of well cementation operation is improved.
A fiber toughness well cementing material adopting a modified toughening material is characterized in that: the composite material comprises the following raw materials in percentage by mass:
70-90% of inorganic gel material, 2-8% of modified toughening material, 1-10% of reinforcing material and 1-15% of filling material;
the modified toughening material comprises the following raw materials in percentage by mass: 70-90% of fiber material, 5-10% of organic dispersing auxiliary agent and 5-20% of inorganic dispersing auxiliary agent; the inorganic dispersing auxiliary agent is a silicon-rich material; the organic dispersing auxiliary agent is a amylopectin substance; the modified toughening material is prepared by the following preparation method:
step A, putting the fiber material and the organic dispersant into a mixing device for mixing and stirring to mix;
step B, putting the mixed prefabricated fiber material obtained in the step A into a ball mill, and grinding for 20-30 min;
and C, putting the ground prefabricated fiber material obtained in the step B and an inorganic dispersant into a mixing device for mixing to obtain the modified toughening material.
The inorganic gel material is one of Portland cement and sulphoaluminate cement.
The reinforcing material is graphite powder, and the graphite powder is one or a mixture of several of flaky graphite powder, spherical graphite powder and colloidal graphite powder; the particle size of the graphite powder is 200-400 meshes, and the purity is more than 80%.
The filling material is superfine calcium carbonate powder, and the specific surface area of the superfine calcium carbonate powder is more than 800 cm2/g。
The fiber material is one or a mixture of more of cellulose fiber and renewable fiber.
The cellulosic fibers include wood fibers and the renewable fibers include pulp fibers derived from paper products.
The fiber length of the fiber material is 0.01-20 mm.
The inorganic dispersing auxiliary agent is one or a mixture of more of fly ash, micro silicon powder and metakaolin.
The amylopectin is potato starch and/or corn starch.
Compared with the prior art, the beneficial technical effects brought by the invention are as follows:
1. the invention adopts starch as the dispersing auxiliary agent, can improve the fiber dispersing performance and reduce agglomeration, and can embody better performance after being mixed with the inorganic gel material. The starch and the silicon-rich material in the modified toughening material are easy to obtain and have low price.
2. The starch is used as a dispersing aid because of the basic principle of non-covalent bond modification, and is a macromolecular carbohydrate formed by dehydrating and polymerizing a plurality of glucose molecules. However, potato starch and corn starch belong to amylopectin, which is the largest of natural high molecular compounds, and amylopectin is easily soluble in water to form a stable solution. The starch and the fiber generate stronger interaction force (such as Van der Waals force, pi-pi stacking effect, hydrogen bond and the like), so that starch molecules are adsorbed on the surface of the fiber, the repulsive force (electrostatic repulsive force or steric hindrance effect) between the sheets is increased, and a stable colloid dispersion system is formed, so that the fiber is not easy to form balls and agglomerate, and the purpose of dispersion is achieved.
3. Compared with the prior art in which starch is directly added into cement, the modified toughening material provided by the application needs to pretreat starch and fiber through a ball mill, pretreat the fiber through the ball mill, damage the surface of the fiber by a ball milling medium, increase the mechanical bonding force between the fiber and a cement stone matrix, and achieve the purpose of increasing the tensile force. Through the ball milling dispersion mode, a plurality of branches or extensions are generated from the surface of the fiber, so that the bonding effect between the fiber and the mineral-based material matrix is improved, the bonding strength between the fiber and cement is facilitated, and the fiber reinforcement performance is more facilitated. Silicon-rich materials such as fly ash, metakaolin, micro-silicon wind and the like are added into the fibers treated by the ball mill, and the fibers can cover the surface of the silicon-rich materials through hydrogen bonds, so that the surface charges of the silicon-rich materials are more negative, and the dispersibility of the silicon-rich materials covered by the fibers in water is enhanced through stronger electrostatic repulsion. Meanwhile, the fibers are dispersed again through mixing, so that the formation of large lumps and large balls is reduced.
4. The modified fiber prepared by the method of the invention increases the doping amount in the well cementation cement, and can increase the doping amount in the well cementation cement to 8 percent due to the improvement of the dispersion performance of the fiber, thereby better reflecting the performance of the fiber.
5. The addition of fiber, graphite and other tough material can raise the fracture resistance of cement stone, but owing to the characteristic of the material affecting the compression strength of cement stone, superfine CaCO is added into the cement3The hydration heat release rate of the cement is promoted, and the hydration heat release is increased along with the superfine CaCO3The addition amount is increased, and the portland cement is hydrated to generate Ca (OH)2The content and the amount of chemically bound water are both increased, and the superfine CaCO3Can be filled in the gap between the fiber and the inorganic cementing material, so that the cement stone is more compact, and the flexural strength and the compressive strength of the cement-based material are improved.
Detailed Description
The technical solution of the present invention is further elaborated below with reference to specific examples.
Example 1
As a preferred embodiment of the present invention, the present embodiment discloses a blending ratio of a modified toughening material, which is specifically as follows:
1. 40% of bagasse, 42% of ramie fibers, 5% of potato starch, 5% of fly ash and 8% of micro silicon; putting bagasse, ramie fiber and potato starch into a mixing device, and mixing for 2 min; then putting the mixture of the bagasse, the ramie fiber and the potato starch which are mixed and stirred into a ball mill, and grinding for 20 min; and (3) putting the mixture of the ground bagasse, ramie fiber and potato starch, the fly ash and the micro-silicon into a mixing device, and mixing for 3min to obtain the modified toughening material A.
2. 70% of paper pulp fiber, 10% of corn starch, 10% of metakaolin and 10% of micro silicon; putting the paper pulp fiber and the corn starch into a mixing device for mixing for 2 min; then putting the mixture of the mixed paper pulp fiber and the corn starch into a ball mill, and grinding for 25 min; and (3) putting the mixture of the ground paper pulp fiber and the corn starch, metakaolin and micro silicon into a mixing device for mixing for 5min to prepare the modified toughening material B.
3. 74% of oak fiber, 3% of potato starch, 3% of corn starch, 5% of fly ash, 8% of microsilica and 7% of metakaolin; placing oak fiber, potato starch and corn starch into mixing equipment, and mixing for 2.5 min; then putting the mixture of the oak fibers, the potato starch and the corn starch into a ball mill for grinding for 28 min; and (3) putting the mixture of the milled oak fibers, potato starch and corn starch, metakaolin, fly ash and microsilica into a mixing device, and mixing for 3min to obtain the modified toughening material C.
4. 40% of ramie fibers, 50% of pulp fibers, 5% of potato starch and 5% of fly ash, and putting the ramie fibers, the pulp fibers and the potato starch into a mixing device for mixing for 3 min; then putting the mixture of the ramie fibers, the pulp fibers and the potato starch into a ball mill for grinding for 30 min; and putting the mixture of the ramie fibers, the pulp fibers and the potato starch after grinding and the fly ash into a mixing device for mixing and stirring for 3min to prepare the modified toughening material D.
Example 2
As another preferred embodiment of the present invention, the embodiment discloses a fiber-reinforced cementing material using a modified reinforced material, which comprises the following specific steps:
the experimental conditions are as follows: the formula of the cement paste is as follows: the cement paste adopts the following formula: the water-cement ratio of the inorganic gel material, the modified toughening material, the reinforcing material, the retarder and the fluid loss agent is 0.44. The retarder and the fluid loss agent are adapted according to different proportional relations, the doping amount is adjusted according to different temperatures, and the retarder and the fluid loss agent both adopt fixed external doping amount percentage which is the integral percentage of the well cementing material.
The experimental method comprises the following steps: the strength and thickening time of the set cement are tested by GB/T19139-2012, and cement paste is prepared according to the test standard GB/T19139-2012.
1. 87% of sulphoaluminate cement, 3% of modified toughening material A, 9% of reinforcing material, 1% of filling material, 0.2% of retarder, 1% of fluid loss agent and 40% of experimental temperature.
2. 80% of G-grade cement, 4% of modified toughening material, 1% of reinforcing material, 15% of filling material, 0.5% of retarder, 1% of fluid loss agent and 50% of test temperature.
3. 90% of G-grade cement, 2% of modified toughening material A, 5% of reinforcing material, 3% of filling material, 0.5% of retarder, 1% of fluid loss additive and 60% of test temperature.
4. 75% of ordinary portland cement, 8% of modified toughening material, 10% of reinforcing material, 7% of filling material, 1% of retarder, 1% of fluid loss additive and 80% of experimental temperature.
5. 70% of ordinary portland cement, 7% of modified toughening material, 8% of reinforcing material, 15% of filling material, 1.2% of retarder and 100 ℃ of experimental temperature.
The test data are shown in the following table:
the data in the table show that the fold-crush ratio of the set cement is more than 4 under different temperature conditions, so that the better toughness is embodied, the thickening time of the cement paste is adjustable, the fluidity of the cement paste can meet the construction requirements, and the better working performance is embodied.
Claims (5)
1. A modified toughening material for well cementation is characterized in that: the composite material comprises the following raw materials in percentage by mass: 70-90% of fiber material, 5-10% of organic dispersing auxiliary agent and 5-20% of inorganic dispersing auxiliary agent; the inorganic dispersing auxiliary agent is a silicon-rich material; the inorganic dispersing auxiliary agent is one or a mixture of more of fly ash, micro silicon powder and metakaolin; the organic dispersing auxiliary agent is a amylopectin substance; the modified toughening material is prepared by the following preparation method:
step A, putting the fiber material and the organic dispersing auxiliary agent into a mixing device for mixing;
step B, putting the mixed prefabricated fiber material obtained in the step A into a ball mill, and grinding for 20-30 min;
and C, putting the ground prefabricated fiber material obtained in the step B and the inorganic dispersing auxiliary agent into a mixing device for mixing, and obtaining the modified toughening material after the mixing is finished.
2. The modified toughening material for well cementation according to claim 1, wherein: the fiber material is one or a mixture of more of cellulose fiber and renewable fiber.
3. The modified toughening material for well cementation according to claim 2, wherein: the cellulosic fibers comprise wood fibers comprising a combination of one or more of oak fibers, aspen fibers, bagasse, and ramie fibers; the renewable fibers include pulp fibers derived from paper products.
4. A modified toughening material for well cementation according to any one of claims 1 to 3, wherein: the fiber length of the fiber material is 0.01-20 mm.
5. A modified toughening material for well cementation according to any one of claims 1 to 3, wherein: the amylopectin is potato starch and/or corn starch.
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CN106675537B (en) * | 2016-12-01 | 2019-11-08 | 中国石油天然气集团公司 | A kind of cementing slurry is with fiber reinforced dose and preparation method thereof |
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