Method for Determining Mixing Ratio of Steel Fiber Recycled Coarse Aggregate Concrete

A technology for regenerating coarse aggregates and determining methods, applied in the field of concrete preparation, can solve the problems of lack of suitable design methods for the selection of steel fiber dosage, difficulty in ensuring stable material properties, and poor comparability of experimental data, etc. The work performance, the calculation formula is simple and reasonable, and the effect of a wide range of applications

Active Publication Date: 2018-08-28
ZHENGZHOU UNIV +1
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Although there are many studies on the mechanical properties of steel fiber recycled concrete, there is no design method suitable for the mix ratio of steel fiber recycled coarse aggregate concrete at home and abroad. Usually, the mix design method of ordinary concrete is used to design the mix ratio. The strength of the steel fiber recycled coarse aggregate concrete configured by the method is generally lower than its design strength, slump, and poor fluidity
In particular, there is no suitable design method for the selection of the amount of steel fiber. Generally, the selection is based on experience, which causes waste of steel fiber to a certain extent.
The design of mix ratio is a key issue in the field of concrete materials, and it is also the basis for studying the basic properties of concrete materials. Since there is no definite design method for the mix ratio of steel fiber recycled coarse aggregate concrete, the comparability of experimental data is poor, and its application is also difficult. More relying on experience, it is difficult to guarantee the stability of material performance

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
  • Method for Determining Mixing Ratio of Steel Fiber Recycled Coarse Aggregate Concrete
  • Method for Determining Mixing Ratio of Steel Fiber Recycled Coarse Aggregate Concrete
  • Method for Determining Mixing Ratio of Steel Fiber Recycled Coarse Aggregate Concrete

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0040] Selected recycled aggregate replacement rate r g =0, the steel fiber selects the milling type (MF). The method for determining the mixing ratio of steel fiber recycled coarse aggregate concrete comprises the following steps:

[0041] (1) Determination of water-binder ratio:

[0042] alpha a =0.53(1-0.1×r g ),α b =0.2(1+0.2×r g ), alpha b = 0.2;

[0043] f ce =45MPa, it can be seen from the above calculation that f cu,0 =49.87MPa, into the formula f cu,0 = α a f ce (C / W-α b ), it can be obtained that W / C=0.43.

[0044] (2) Determination of the amount of steel fiber:

[0045] The target bending and tensile strength of concrete f tm =10MPa; target compressive strength of concrete cube f cu =40MPa

[0046] According to CEB-FIP (1990), (f c ' is the standard cylinder compressive strength of concrete), according to f tm,0 =5.03MPa;

[0047] Due to the calculated bending and tensile strength of the plain concrete matrix (f tm,0 =5.03MPa) is less than...

Embodiment 2

[0067] Selected recycled aggregate replacement rate r g=50%, the steel fiber selects the milling type MF, the method for determining the mixing ratio of the steel fiber recycled coarse aggregate concrete includes the following steps:

[0068] (1) Determination of water-binder ratio:

[0069] alpha a =0.53(1-0.1×r g ),α b =0.2(1+0.2×r g ), alpha b =0.22;

[0070] will f ce =45MPa, f cu,0 =49.87MPa into the formula f cu,0 = α a f ce (C / W-α b ), it can be obtained that W / C=0.41. (2) Determination of the amount of steel fiber:

[0071] The target bending and tensile strength of concrete f tm =10MPa; concrete cube target compressive strength, f cu =40MPa;

[0072] Steel fiber type and aspect ratio are all identical with embodiment 1, and its calculation process is identical with embodiment 1, and the result can get: λ f =0.63, V f = 1.84%.

[0073] (3) Determination of unilateral water consumption:

[0074] Set slump T=50mm, the steel fiber content characteris...

Embodiment 3

[0093] Selected recycled aggregate replacement rate r g =100%, the steel fiber selects the milling type MF, and the method for determining the mix ratio of steel fiber recycled coarse aggregate concrete includes the following steps:

[0094] (1) Determination of water-binder ratio:

[0095] alpha a =0.53(1-0.1×r g ),α b =0.2(1+0.2×r g ), alpha b =0.24;

[0096] will f cu,0 =49.87MPa, f ce =45MPa into the formula f cu,0 = α a f ce (C / W-α b ), it can be obtained that W / C=0.39. (2) Determination of the amount of single steel fiber:

[0097] The target bending and tensile strength of concrete f tm = 10MPa, the target compressive strength of concrete cube f cu =40MPa;

[0098] Steel fiber type and aspect ratio are all identical with embodiment 1, and its calculation process is identical with embodiment 1, λ f =0.63, V f = 1.84%. (3) Determination of unilateral water consumption:

[0099] Set slump T=50mm, the steel fiber content characteristic parameter λ that...

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
densityaaaaaaaaaa
compressive strengthaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for determining a steel fiber regenerative coarse aggregate concrete mix proportion. According to the method, on the basis of studying the effects of all performance indexes of regenerative coarse aggregate and steel fiber on the mix proportion of the regenerative coarse aggregate and the steel fiber, a computational formula, suitable for characters of the steel fiber regenerative coarse aggregate concrete, of a water-binder ratio, the steel fiber amount, the single-cubic water consumption amount and the sand volume is established. The method comprises the first step of determining the water-binder ratio, the second step of determining the steel fiber amount, the third step of determining the single cubic water consumption amount, the fourth step of determining the sand volume, the fifth step of determining the cement amount, and the sixth step of determining the volumes and masses of the components. The mix proportion designing method can be easily and effectively used for mix proportion design of steel fiber regenerative coarse aggregate concrete, and a basis is provided for standard organization of the steel fiber regenerative coarse aggregate concrete and the practical engineering application.

Description

technical field [0001] The invention belongs to the technical field of concrete preparation, and in particular relates to a method for determining the mixing ratio of steel fiber recycled coarse aggregate concrete. technical background [0002] Recycled concrete refers to concrete that uses waste concrete as aggregate after crushing and processing. The use of recycled concrete not only fundamentally solves the problem of waste concrete disposal, but also completely or partially replaces natural aggregates, reducing the use and mining of natural aggregates. , has significant economic, social and environmental benefits. Compared with natural aggregate, recycled aggregate has low apparent density, high water absorption, and many pores, so the performance of recycled coarse aggregate has a certain influence on the utilization of concrete. At present, recycled coarse aggregate concrete is mostly used for road and filling and other non-structural fields. In order to expand the a...

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 Patents(China)
IPC IPC(8): C04B28/00
CPCC04B28/00C04B2111/00017C04B14/48C04B18/16C04B14/06
Inventor 高丹盈张丽娟杨震
Owner ZHENGZHOU 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