Special mixed cement for on-site preparation of concrete as well as preparation method and application

A technology for mixing cement and concrete, applied in cement production, etc., can solve problems such as increased cracking risk, lack, and shortage, and achieve the effects of improving homogeneity and quality stability, simplifying the preparation process, and preventing early cracking

Active Publication Date: 2019-11-22
程菲 +1
View PDF3 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

and little or no SO in the admixture 3 , only by SO in cement 3 , affecting the sulfate ion content in the cement system, which may aggravate the poor adaptability between the cementitious material and the water reducer, and will lead to the SO required for the hydration reaction of the cementitious material in concrete 3 severely deficient

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Special mixed cement for on-site preparation of concrete as well as preparation method and application
  • Special mixed cement for on-site preparation of concrete as well as preparation method and application
  • Special mixed cement for on-site preparation of concrete as well as preparation method and application

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0039] A method for preparing special mixed cement for on-site concrete preparation, using general-purpose Portland cement of grade 42.5 and above and other raw material micropowders that have been ground into corresponding fineness through ball mills or vertical mills. Process additives can be added during grinding; the steps are:

[0040] Step 1, raw material selection, general-purpose portland cement, admixture, gypsum, limestone, composite modified water reducer and other functional admixtures of 42.5 grade and above are tested, and the raw materials that meet the regulations are allowed to be put into the next production process.

[0041] Step 2. When preparing, limestone, admixture, gypsum, and process additives are pre-mixed individually or any of them according to the mass ratio, and then ground by a ball mill or a vertical mill to make a specific surface area ≥ 330m 2 / kg and ≤450m 2 / kg, and the corresponding type of micropowder with the mass of ≤3um micropowder acc...

Embodiment 1

[0051] A special mixed cement for concrete prepared on site, its mass ratio is: 42.5 grade ordinary portland cement 60%, gypsum 6%, limestone 5%, admixture materials (fly ash, granulated blast furnace slag) 26.5%, functional Admixture (composite modified superplasticizer) 2.5%. Component materials meet relevant standards and requirements. The preparation method and specific steps are as follows:

[0052] The 42.5 ordinary Portland cement must meet the requirements of GB175, and its control parameters: the proportion of fine powder of ≤3um is ≤10%, the compressive strength of 1 day is ≤12MPa, the compressive strength of 3 days is ≥20MPa, and the compressive strength of 28 days Strength ≥ 45MPa, water consumption for standard consistency of cement paste ≤ 28%, alkali content requirement 2 O and Na 2 The sum of O represents that the chloride ion content is 2 / kg and ≤450m 2 / kg, wherein the mass proportion of fine powder ≤ 3um is ≥ 15%; the alkali content in the mixed material...

Embodiment 2

[0061] A special mixed cement for concrete prepared on site, its mass ratio is: 42.5 grade ordinary Portland cement 65%, gypsum 4%, limestone 10%, admixture (slag, granulated blast furnace slag) 20.5%, functional admixture (Composite modified water reducer) 0.5%. The component materials meet the relevant standards and the aforementioned requirements. Others are the same as embodiment 1.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Specific surface areaaaaaaaaaaa
Compressive strengthaaaaaaaaaa
Specific surface areaaaaaaaaaaa
Login to view more

Abstract

The invention relates to the field of cement and concrete. The invention discloses special mixed cement for on-site preparation of concrete as well as a preparation method and application. Except formixing and grinding cement clinker and other raw materials, the mixed cement is prepared from the following components in percentage by mass: 60%-80% of general Portland cement of the 42.5 grade or above, 3.0%-6.0% of gypsum, 5%-15% of limestone, 2%-29% of an admixture and 0.5%-3.0% of a functional additive. The general Portland cement with the grade of 42.5 or above meets the requirements of GB175, and parameters of the general Portland cement are controlled such that the mass ratio of the micro powder less than or equal to 3 [mu]m is less than or equal to 10%, the one-day compressive strength is less than or equal to 12 MPa, the 3-day compressive strength is more than or equal to 20 MPa, the 28-day compressive strength is more than or equal to 45 MPa, the water consumption of the standard consistency of the cement paste is less than or equal to 28%, the alkali content is less than 0.6% in terms of 0.658 K2O + Na2O, and the chloride ion content is less than 0.06%. The raw materials are wide in source, the mixed cement can be directly used for preparing or premixing concrete on site, no admixture or functional additive needs to be added again, crack resistance, workability and themechanical property of the concrete are improved, and construction operation is simplified.

Description

technical field [0001] The invention relates to the technical field of cement and concrete production, in particular to a special mixed cement for on-site preparation of concrete and its preparation method and application. Background technique [0002] According to the design, construction and acceptance specifications of construction projects, the concrete strength of various parts of common construction projects can be divided into: ① general cushion C10-C15; pile concrete generally above C30; foundation beams, slabs, caps, and columns generally C25-C35 ; ② wall columns are generally C20-C35 (according to the building needs higher strength); ③ floors are generally C20-C30; ④ other secondary structures are generally C20-C30. [0003] According to statistics, domestic C15-C30 strength grade concrete accounts for more than 75% of all concrete. In 2018, the largest commercial concrete company in Hunan Province sold 16.5 million cubic meters of commercial concrete, and the weig...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): C04B7/147C04B7/26C04B7/36C04B28/08C04B28/04
CPCC04B7/147C04B7/26C04B7/36C04B28/04C04B28/082C04B2201/50C04B22/002C04B14/06C04B14/00Y02P40/10
Inventor 陈克坚冷发光丁美荣周永祥司丙艳罗俊雄王祖琦黄维瑶岳仍慧
Owner 程菲
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap