CN115925304B - Special square and round particle machine-made sand for high-strength concrete - Google Patents
Special square and round particle machine-made sand for high-strength concrete Download PDFInfo
- Publication number
- CN115925304B CN115925304B CN202211491445.5A CN202211491445A CN115925304B CN 115925304 B CN115925304 B CN 115925304B CN 202211491445 A CN202211491445 A CN 202211491445A CN 115925304 B CN115925304 B CN 115925304B
- Authority
- CN
- China
- Prior art keywords
- machine
- made sand
- parts
- concrete
- calcium sulfate
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Abstract
The invention relates to the technical field of production of machine-made sand, and provides special square and round granular machine-made sand for high-strength concrete, wherein the machine-made sand is subjected to modification treatment before use, and the modification treatment comprises the following steps: s1, preparing a polyacrylonitrile-DMF solution, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified liquid; s2, soaking the machine-made sand in the modifying liquid, stirring, taking out and drying to obtain the modified machine-made sand. Through the technical scheme, the problems of poor workability, large slump loss and low concrete strength of machine-made sand concrete in the prior art are solved.
Description
Technical Field
The invention relates to the technical field of machine-made sand production, in particular to special square and round particle machine-made sand for high-strength concrete.
Background
With the development of urban construction, the use amount of concrete is increased, natural sand resources are also increased and tensioned, meanwhile, in order to protect river dikes and dams and ecological balance, many sand fields are changed and shut down, small sand fields are eliminated, natural sand resources are further in shortage, natural sand is a local resource and is not renewable in a short period, and the price of high-quality natural river sand is rapidly increased and the supply is unstable. Under the drive of economic benefits, the random mining and the random digging in many places have caused serious environmental pollution problems. Therefore, in order to protect the ecological environment, the production cost of concrete is reduced, and machine-made sand is adopted as a substitute for natural river sand and gradually applied to the concrete.
The machine-made sand is artificial sand processed by a sand making machine and other accessory equipment, and has larger usage in concrete. Because the machine-made sand is formed by crushing by artificial machinery, a certain amount of stone powder exists, the main chemical component of the stone powder is calcium carbonate, although the stone powder can take part in cement hydration reaction to obtain some good effects, the quantity of the stone powder which can participate in the cement hydration reaction is very limited, redundant stone powder can be dissociated at the periphery to influence the workability and strength of concrete, and secondly, the machine-made sand is irregular in shape, poor in particle shape roundness and high in surface roughness, so that the prepared concrete is generally poor in workability and large in slump loss, and the strength of the concrete is reduced.
Disclosure of Invention
The invention provides square and round granular machine-made sand special for high-strength concrete, which solves the problems of poor workability, large slump loss and low concrete strength of machine-made sand concrete in the related technology.
The technical scheme of the invention is as follows:
the machine-made sand is subjected to modification treatment before use, and the modification treatment comprises the following steps of:
s1, preparing a polyacrylonitrile-DMF solution, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified liquid;
s2, soaking the machine-made sand in the modifying liquid, stirring, taking out and drying to obtain the modified machine-made sand.
As a further technical scheme, the DMF is N, N-dimethylformamide.
As a further technical scheme, the mass concentration of the polyacrylonitrile-DMF solution in the S1 is 3-5%.
As a further technical scheme, the mass ratio of the calcium sulfate whisker to the polyacrylonitrile-DMF solution in the S1 is (0.8-1): 10.
As a further technical scheme, the length of the calcium sulfate whisker in the S1 is 10-200 mu m, and the diameter is 1-4 mu m.
As a further technical scheme, the mass ratio of the machine-made sand to the modifying liquid in the step S2 is (2-3): 10.
As a further technical scheme, the mass ratio of the machine-made sand to the modifying liquid in the S2 is 3:10.
The concrete comprises machine-made sand, cement, a water reducing agent, silica fume, fly ash, crushed stone and water.
As a further technical scheme, the concrete comprises, by weight, 90-100 parts of cement, 3-5 parts of a water reducer, 15-30 parts of silica fume, 15-25 parts of fly ash, 150-180 parts of crushed stone, 150-180 parts of machine-made sand and 30-40 parts of water.
As a further technical scheme, the water reducer comprises one of a polycarboxylic acid water reducer and an sulfamate water reducer.
A preparation method of concrete comprises the step of uniformly mixing cement, silica fume, fly ash, machine-made sand, broken stone, a water reducing agent and water to obtain the concrete.
The working principle and the beneficial effects of the invention are as follows:
1. according to the invention, the polyacrylonitrile and the calcium sulfate whisker are used for modifying the machine-made sand, so that the roundness of the machine-made sand is improved, and in the process of modifying the machine-made sand, the polyacrylonitrile and the calcium sulfate whisker have a synergistic effect, so that the workability of the machine-made sand concrete is improved, the slump loss is reduced, and the mechanical property of the concrete is improved.
2. According to the invention, on one hand, the machined sand is used as a carrier, so that the dispersibility of the calcium sulfate whisker in a concrete system is improved, the problem that the dispersibility of the calcium sulfate whisker in the concrete is poor due to the fact that the calcium sulfate whisker is directly added into the concrete in the traditional process is avoided, the best effect of reinforcing the concrete strength by the calcium sulfate whisker is achieved, on the other hand, the polyacrylonitrile is used for coating the calcium sulfate whisker on the surface of the machined sand, the workability of the machined sand concrete is improved, and the slump loss is reduced.
3. According to the modified machine-made sand, the calcium sulfate whisker and the polyacrylonitrile are attached to the surface, so that on one hand, the extra stone powder in the machine-made sand is adsorbed by the polyacrylonitrile, the problem of poor workability of concrete caused by the fact that the extra stone powder is dissociated at the periphery is avoided, and meanwhile, the strength of the concrete is improved; on the other hand, the calcium sulfate whisker attached to the surface of the machine-made sand further improves the workability of the machine-made sand concrete, is beneficial to the construction process of the concrete, and improves the mechanical property of the concrete.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The calcium sulfate whiskers in the following examples and comparative examples were calcium sulfate whiskers having a length of 10 to 200 μm and a diameter of 1 to 4 μm, available from Hanteng plastics Inc. in Dongguan; the cement is ordinary Portland cement, PO42.5, purchased from the Ministry of Siqing of Tianjin, jin Danyong Wang building materials manager; sulfamate water reducers were purchased from laucing building materials limited in laucing city; the polycarboxylate water reducer is purchased from Shandong HongYi chemical group Co., ltd; silica fume was purchased from Shijia's Renmbo mineral products processing Co.Ltd; the fly ash is first-grade fly ash and is purchased from a Ming-Hui county Detong mineral product processing plant; the broken stone is 5-25 mm broken stone, and the company is self-produced; the machine-made sand has fineness modulus not more than 4, stone powder content less than 10wt% and mud content less than 0.5wt%, and is produced by the company.
Example 1
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 2
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2.5:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 3
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 3:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 4
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 5%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified liquid, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 1:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 3:10;
and S3, uniformly mixing 100 parts of cement, 5 parts of sulfamate water reducer, 30 parts of silica fume, 25 parts of fly ash, 180 parts of crushed stone, 180 parts of machine-made sand and 40 parts of water to obtain the concrete.
Example 5
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 1:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylic acid water reducer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 6
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 4:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylic acid water reducer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 7
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 0.5:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Example 8
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3%, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified solution, wherein the mass ratio of the calcium sulfate whiskers to the polyacrylonitrile-DMF solution is 1.5:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Comparative example 1
The only difference from example 1 is that the calcium sulfate whisker has a length of 30 to 200. Mu.m, and a diameter of 1 to 8. Mu.m.
Comparative example 2
S1, uniformly stirring calcium sulfate whisker and DMF to obtain a modified liquid, wherein the mass ratio of the calcium sulfate whisker to the DMF is 0.8:10;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Comparative example 3
S1, preparing a polyacrylonitrile-DMF solution with the mass concentration of 3% to obtain a modified solution;
s2, soaking the machine-made sand in the modified liquid obtained in the step S1, stirring, taking out and drying to obtain modified machine-made sand, wherein the mass ratio of the machine-made sand to the modified liquid is 2:10;
and S3, uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water to obtain the concrete.
Comparative example 4
The concrete is prepared by uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of broken stone, 150 parts of machine-made sand and 30 parts of water.
Comparative example 5
The only difference from example 1 is that the polyacrylonitrile in S1 is replaced by an equivalent amount of polyvinyl alcohol.
Comparative example 6
The concrete is prepared by uniformly mixing 90 parts of cement, 3 parts of polycarboxylate superplasticizer, 15 parts of silica fume, 15 parts of fly ash, 150 parts of crushed stone, 55 parts of calcium sulfate whisker, 20 parts of polyacrylonitrile, 150 parts of machine-made sand and 30 parts of water.
The slump of the concrete obtained in examples 1 to 8 and comparative examples 1 to 6 was measured according to GB/T50080-2016 Standard for Performance test of common concrete mixtures; the compressive strength of the hardened concrete was measured according to the relevant specifications of GB/T50081 2002 Standard for test method for mechanical Properties of general concrete. The test results are shown in Table 1:
table 1 concrete test results
As can be seen from Table 1, the concrete provided by the examples 1 to 4 of the present invention using the preferable machine-made sand has good workability, small slump loss, and excellent mechanical properties at 28d compressive strength of 54.6MPa or more.
Since the mass ratio of the machine-made sand to the modifying liquid in the process of modifying the machine-made sand in the examples 5 and 6 exceeds the range of (2-3): 10, the mass ratio of the calcium sulfate whisker to the polyacrylonitrile-DMF solution in the examples 7 and 8 is not in the range of (0.8-1): 10, resulting in that the slump loss and mechanical properties of the concrete in the examples 5, 7 and 8 are not as good as those of the concrete in the examples 1-4, and the 28d compressive strength of the concrete in the example 6 is lower than that of the concrete in the examples 1-4. Therefore, in the process of modifying the machine-made sand, when the mass ratio of the calcium sulfate whisker to the polyacrylonitrile-DMF solution is (0.8-1): 10 and the mass ratio of the machine-made sand to the modifying solution is (2-3): 10, the workability, slump loss and mechanical property of the concrete are provided to be optimal.
Comparative example 1 differs from example 1 only in that the calcium sulfate whisker in comparative example 1 has a length of 30 to 200 μm and a diameter of 1 to 8. Mu.m, and as can be seen from Table 1, the slump loss and compressive strength of the concrete obtained in comparative example 1 are not as good as those of example 1.
Comparative example 2 in the course of modifying the machine-made sand, polyacrylonitrile was not added; comparative example 3 no calcium sulfate whisker was added during the modification of the machine-made sand; comparative example 4 did not modify the machine-made sand; the concrete provided by comparative examples 2 to 4 was inferior in all respects to that of example 1. Comparing the concrete test results provided in comparative examples 2 to 4 with those provided in example 1, it was found that polyacrylonitrile and calcium sulfate whisker have a synergistic effect in the process of modifying machine-made sand, and the compressive strength of the concrete was improved.
Comparative example 5 differs from example 1 only in that the polyacrylonitrile in S1 was replaced with an equivalent amount of polyvinyl alcohol, and the concrete obtained in comparative example 5 was inferior in slump loss and mechanical properties to those of example 1.
Comparative example 6 differs from example 1 only in that polyacrylonitrile and calcium sulfate whiskers are directly added to concrete, and no machine-made sand is modified, resulting in uneven dispersion of calcium sulfate whiskers in the concrete system, and the added polyacrylonitrile exists in the form of powder in the concrete system, which affects workability of concrete, so that slump loss and compressive strength of the resulting concrete are not as good as those of example 1.
The foregoing description of the preferred embodiments of the invention is not intended to be limiting, but rather is intended to cover all modifications, equivalents, alternatives, and improvements that fall within the spirit and scope of the invention.
Claims (6)
1. The square and round granular machine-made sand special for the high-strength concrete is characterized by being subjected to modification treatment before being used, and the modification treatment comprises the following steps of:
s1, preparing a polyacrylonitrile-DMF solution, adding calcium sulfate whiskers, and uniformly stirring to obtain a modified liquid;
s2, soaking the machine-made sand in the modifying liquid, stirring, taking out and drying to obtain modified machine-made sand;
the mass concentration of the polyacrylonitrile-DMF solution in the S1 is 3-5%;
the mass ratio of the calcium sulfate whisker to the polyacrylonitrile-DMF solution in the S1 is (0.8-1) 10;
the length of the calcium sulfate whisker in the S1 is 10-200 mu m, and the diameter is 1-4 mu m;
the mass ratio of the machine-made sand to the modifying liquid in the step S2 is (2-3) to 10.
2. The special square and round granular machine-made sand for high-strength concrete according to claim 1, wherein the mass ratio of the machine-made sand to the modifying liquid in the S2 is 3:10.
3. The concrete is characterized by comprising the machine-made sand according to any one of claims 1-2, and further comprising cement, a water reducing agent, silica fume, fly ash, crushed stone and water.
4. The concrete of claim 3, wherein the concrete comprises, by weight, 90-100 parts of cement, 3-5 parts of a water reducing agent, 15-30 parts of silica fume, 15-25 parts of fly ash, 150-180 parts of crushed stone, 150-180 parts of machine-made sand and 30-40 parts of water.
5. A concrete according to claim 3, wherein the water reducing agent comprises one of a polycarboxylate type water reducing agent and an sulfamate type water reducing agent.
6. A method for preparing concrete according to claim 3, wherein cement, silica fume, fly ash, machine-made sand, broken stone, water reducing agent and water are uniformly mixed to obtain the concrete.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211491445.5A CN115925304B (en) | 2022-11-25 | 2022-11-25 | Special square and round particle machine-made sand for high-strength concrete |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211491445.5A CN115925304B (en) | 2022-11-25 | 2022-11-25 | Special square and round particle machine-made sand for high-strength concrete |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115925304A CN115925304A (en) | 2023-04-07 |
| CN115925304B true CN115925304B (en) | 2023-07-07 |
Family
ID=86653387
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211491445.5A Active CN115925304B (en) | 2022-11-25 | 2022-11-25 | Special square and round particle machine-made sand for high-strength concrete |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115925304B (en) |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101863631B (en) * | 2010-06-21 | 2012-01-04 | 东南大学 | Stone aggregate wrapped by microfine fibre polymer mortar thin layer and preparation method thereof |
| RU2655187C1 (en) * | 2017-04-12 | 2018-05-25 | Открытое акционерное общество "Завод Магнетон" | Radar-absorbent composite material for construction applications and method for production thereof |
| CN111285949B (en) * | 2020-02-13 | 2021-07-06 | 山东大学 | Polyacrylonitrile-coated graphene composite material and preparation method and application thereof |
| CN113457475A (en) * | 2021-07-09 | 2021-10-01 | 武汉纺织大学 | Polyacrylonitrile/nano whisker composite ultrafiltration membrane and preparation method thereof |
| CN114436588A (en) * | 2022-01-24 | 2022-05-06 | 江苏昆腾新材料科技有限公司 | High-workability concrete containing modified machine-made sand and preparation method thereof |
| CN115028415B (en) * | 2022-07-08 | 2023-03-17 | 江苏省科佳工程设计有限公司 | High-strength premixed pervious concrete and preparation method thereof |
-
2022
- 2022-11-25 CN CN202211491445.5A patent/CN115925304B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN115925304A (en) | 2023-04-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN106587831B (en) | A kind of superhigh-lift pumping maritime concrete and preparation method thereof | |
| CN107459311B (en) | Preparation method of waste-utilizing, fracture-resisting and toughening wet-grinding slurry-like admixture | |
| CN107540309B (en) | Slope protection prefabricated part concrete containing iron tailings and preparation method thereof | |
| CN104402345A (en) | High fluidization micro expansive high-strength grouting material | |
| CN108585679B (en) | Low-shrinkage green UHPC and preparation method thereof | |
| CN110526613B (en) | Special superfine sand pump concrete polycarboxylate superplasticizer for aluminum mold | |
| CN112777986B (en) | Machine-made sand ultra-high performance concrete and preparation method thereof | |
| CN111606621B (en) | Bare concrete for bridge structure in marine environment and preparation method thereof | |
| CN113651574B (en) | Counterweight cement-based composite material and preparation method thereof | |
| CN109809778A (en) | Super hardening modified PVA fiber reinforcement sea sand cement-base composite material and preparation method thereof | |
| CN113816696A (en) | Recycled fine aggregate internal curing-based ultrahigh-performance concrete and preparation method thereof | |
| CN106810161A (en) | A kind of Graphene concrete composite material of resisting erosion of sulfate and preparation method thereof | |
| CN111704405B (en) | Sisal hemp nano cellulose ultra-high toughness concrete and preparation method thereof | |
| CN113173764B (en) | High-strength anti-cracking concrete and preparation process thereof | |
| CN114180914A (en) | High-strength concrete prepared by applying cobbles | |
| CN115925304B (en) | Special square and round particle machine-made sand for high-strength concrete | |
| CN110218042B (en) | Environment-friendly high-strength dry-mixed mortar and preparation method thereof | |
| CN113831090B (en) | Large-flow-state anti-seepage impact-resistant grinding hydraulic concrete and preparation method thereof | |
| CN107522421B (en) | Concrete mineral admixture, preparation method thereof and concrete | |
| CN110171940B (en) | Coral sand admixture and preparation method and application thereof | |
| CN114315242A (en) | Recycled steel fiber concrete and preparation method thereof | |
| CN113666676A (en) | Underwater concrete repairing and reinforcing material and preparation method thereof | |
| CN113620664B (en) | Ultrahigh-performance concrete and preparation method thereof | |
| CN110922521A (en) | Anti-adsorption agent for concrete and preparation method thereof | |
| CN110981332A (en) | Dry-mixed plastering mortar for building solid waste recycled aggregate and preparation method thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |