Compound admixture for anti-crack limestone powder and preparation method of compound admixture

A composite admixture and limestone powder technology, which is applied in the field of anti-cracking limestone powder composite admixture and its preparation, can solve the problems of affecting the working performance and mechanical properties of concrete, the reduction of concrete crack resistance, and the reduction of crack resistance. It is beneficial to the development of early strength, enhances the ability to resist plastic shrinkage cracking, and weakens the effect of tensile stress

Pending Publication Date: 2017-05-10
CENT SOUTH UNIV
View PDF3 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] Scholars at home and abroad have done a lot of research on limestone powder concrete, pointing out that limestone powder can improve the early strength of concrete and increase the fluidity of concrete, but with the increase of limestone powder content, the crack resistance of concrete increases first and then decreases. Small change rule, when the limestone powder content reaches the peak value, the range is 10%-20%, so when the limestone powder content is less than 10%, the cement-based cementitious material shrinks, and its crack resistance performance is reduced
[0006] In summary, the use of limestone powder in the amount specified in the current code will lead to a decrease in the crack resistance of concrete. In order to improve the crack resistance of limestone powder concrete, it is necessary to invent a crack-resistant limestone powder composite admixture
[0007] There are some methods to improve crack resistance in the prior art, although they can prevent cracking to a certain extent, they will affect the working performance and mechanical properties of concrete to a certain extent

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
  • Compound admixture for anti-crack limestone powder and preparation method of compound admixture
  • Compound admixture for anti-crack limestone powder and preparation method of compound admixture
  • Compound admixture for anti-crack limestone powder and preparation method of compound admixture

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0045] The weight percent of each component of an anti-cracking limestone powder composite admixture is: Blaine's specific surface area is 350m 2 / kg limestone powder 70%; 0.045mm square hole sieve is 10% Class I fly ash 28.85%; single filament diameter 27-32μm, aspect ratio 40, density 0.91g / cm 3, modulus of elasticity 40GPa, elongation at break 30% of polypropylene fiber 1%, triethanolamine 0.15%. Mix the weighed limestone powder, fly ash, polypropylene fiber and triethanolamine uniformly in a mixer to obtain the crack-resistant limestone powder composite admixture III.

[0046] The anti-cracking limestone powder composite admixture III is used to prepare concrete, the mix ratio is shown in Table 4, and the properties of the concrete are shown in Table 5 and Table 6.

[0047] The raw materials for preparing concrete are as follows: 42.5 ordinary Portland cement is used for cement, river sand with a fineness modulus of 2.6 is used for fine aggregate, 5-25mm continuously grad...

Embodiment 2

[0071] The weight percent of each component of an anti-cracking limestone powder composite admixture is: Blaine's specific surface area is 350m 2 / kg of limestone powder 65%; 0.045mm square hole sieve 17% grade II fly ash 33.3%; single filament diameter 27-32μm, aspect ratio 40, density 0.91g / cm 3 , modulus of elasticity 40GPa, elongation at break 30% of polypropylene fiber 1.5%, triethanolamine 0.2%. Mix the weighed limestone powder, fly ash, polypropylene fiber and triethanolamine uniformly in a mixer to obtain the crack-resistant limestone powder composite admixture VI.

[0072] Use anti-cracking limestone powder composite admixture VI to prepare concrete, the mix ratio is shown in Table 10, and the properties of the concrete are shown in Table 11 and Table 12.

[0073] The raw materials for preparing concrete are as follows: 42.5 ordinary Portland cement is used for cement, river sand with a fineness modulus of 2.6 is used for fine aggregate, 5-25mm continuously graded cr...

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
diameteraaaaaaaaaa
elastic modulusaaaaaaaaaa
Login to view more

Abstract

The invention provides a compound admixture for anti-crack limestone powder and a preparation method of the compound admixture. The compound admixture comprises, by mass, 60-70 parts of limestone powder, 28-40 parts of coal ash, 1-2 parts of polypropylene fibers and 0.1-0.2 part of triethanolamine. By the compound admixture for the anti-crack limestone powder, concrete contraction can be reduced and concrete anti-crack performance can be improved while working performance and mechanical performance of concrete are guaranteed, so that durability of limestone powder concrete is improved, and application of the limestone powder to the concrete is widened.

Description

technical field [0001] The invention belongs to the field of concrete, and in particular relates to a crack-resistant limestone powder composite admixture and a preparation method thereof. Background technique [0002] With the continuous development of large-scale infrastructure construction, a large amount of stone powder is produced during the mining and crushing of aggregates in the process of concrete engineering construction. If these stone powders are not properly used, they will cause serious environmental burdens and waste of resources. [0003] Limestone is widely distributed and has abundant reserves, so a large amount of limestone powder will be produced during the aggregate mining process. Using limestone powder as a concrete mineral admixture is not only in line with the green concrete advocated by the state, but also brings greater social and economic benefits; it can also solve the problem of It is difficult to supply traditional mineral admixtures (such as f...

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
Patent Type & Authority Applications(China)
IPC IPC(8): C04B24/12
CPCC04B40/0039C04B14/28C04B18/08C04B16/0633C04B24/122C04B28/04
Inventor 肖佳郭明磊王佳雷田承宇徐勇
Owner CENT SOUTH UNIV
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