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CN-121974634-A - Recycled concrete composite material and preparation method and application thereof

CN121974634ACN 121974634 ACN121974634 ACN 121974634ACN-121974634-A

Abstract

The invention relates to the technical field of engineering and building materials, in particular to a recycled concrete composite material and a preparation method and application thereof. The recycled concrete composite material provided by the invention realizes that the recycled concrete composite material with high strength is obtained under the premise of ensuring the replacement rate of recycled aggregate through the synergistic effect of the components, has low cost, realizes the dual purposes of economic benefit and performance enhancement, and has wide application prospect. The recycled concrete composite material provided by the invention has high strength and high recycled aggregate replacement rate, the strength performance is improved while the cost is reduced, the performances such as chloride ion diffusion coefficient and the like are not obviously reduced, even improved, the comprehensive performance is obviously improved, and the recycled concrete composite material can be used in the field of road engineering, such as roadbed, retaining wall and other application scenes, and especially meets the performance requirements of honeycomb roadbed.

Inventors

  • YIN YONGGAO
  • CAI JUNHAO

Assignees

  • 合肥工业大学

Dates

Publication Date
20260505
Application Date
20260407

Claims (10)

  1. 1. The recycled concrete composite material is characterized by comprising the following components in parts by weight: 10 parts of cement, 2-4 parts of fly ash, 10-18 parts of recycled coarse aggregate, 5-6 parts of polyethylene terephthalate, 2-3 parts of polyoxymethylene, 8-13 parts of fine aggregate, 0.1-0.5 part of water reducer and 5-10 parts of water.
  2. 2. The recycled concrete composite of claim 1, wherein the fly ash has a particle size of 1-20 microns.
  3. 3. The recycled concrete composite of claim 1, wherein the recycled coarse aggregate is a class I recycled coarse aggregate.
  4. 4. The recycled concrete composite of claim 1, wherein the polyethylene terephthalate has a melting point of 250-260 degrees celsius.
  5. 5. The recycled concrete composite of claim 1, wherein the polyoxymethylene is a polyoxymethylene homopolymer; the melting point of the polyoxymethylene is 175-185 ℃.
  6. 6. The recycled concrete composite of claim 1, wherein the fine aggregate is river sand; The fineness modulus of the fine aggregate is 2.6-3.
  7. 7. The recycled concrete composite of claim 1, wherein the water reducer is a polycarboxylic acid high performance water reducer.
  8. 8. A method for preparing a recycled concrete composite material, wherein the recycled concrete composite material is the recycled concrete composite material according to any one of claims 1 to 7, and the method is characterized by comprising the following steps: (1) Mixing the recycled coarse aggregate, polyethylene terephthalate and polyoxymethylene, and sequentially heating, heat treating and cooling to obtain modified aggregate; (2) And mixing the modified aggregate with cement, fly ash, fine aggregate, a water reducing agent and water to obtain the recycled concrete composite material.
  9. 9. The method for preparing a recycled concrete composite material according to claim 8, wherein the heating rate of heating is 20-25 ℃ per minute; The temperature of the heat treatment is 260-270 ℃, and the heat preservation time is 30-50 minutes; The cooling rate is 5-10 ℃ per minute.
  10. 10. The application of the recycled concrete composite material in the field of road engineering is characterized in that the recycled concrete composite material is the recycled concrete composite material according to any one of claims 1-7 or the recycled concrete composite material obtained by the preparation method according to any one of claims 8-9.

Description

Recycled concrete composite material and preparation method and application thereof Technical Field The invention relates to the technical field of engineering and building materials, in particular to a recycled concrete composite material and a preparation method and application thereof. Background With the development of the fields of construction and engineering, concrete materials are one of the most commonly used materials, and the performance level thereof has become one of the important factors for the development of the fields. Therefore, how to improve the performance of concrete materials has been a major concern in the field of concrete materials. The regenerated concrete is used as a green building material, and is prepared from waste concrete blocks through crushing, washing, grading, mixing with grading, replacing sand stone and other natural aggregate (coarse aggregate), and adding cement, water and other materials. The appearance and development of the recycled concrete are important achievements for recycling the construction waste, and aim to solve the problems of resource waste and environmental pollution caused by the traditional landfill mode. Although the recycled concrete has good social and economic benefits, the application of the recycled concrete is limited by the performance deficiency, for example, the compressive strength of the recycled concrete is generally 70-90% of that of common concrete, and is reduced along with the increase of the replacement rate of the recycled aggregate, and when the replacement rate of the recycled aggregate exceeds 30%, the flexural strength of the recycled concrete is reduced by more than 15%. This is mainly due to the low strength of recycled aggregate and the internal microcracks that develop during crushing, which tend to form stress concentrations when subjected to axial stresses. Therefore, how to prepare recycled concrete with high strength on the premise of ensuring the replacement rate of recycled aggregate is a problem facing the person skilled in the art. Disclosure of Invention In view of the above, the invention provides a recycled concrete composite material, a preparation method and application thereof. The invention provides a recycled concrete composite material which comprises the following components in parts by weight: 10 parts of cement, 2-4 parts of fly ash, 10-18 parts of recycled coarse aggregate, 5-6 parts of polyethylene terephthalate, 2-3 parts of polyoxymethylene, 8-13 parts of fine aggregate, 0.1-0.5 part of water reducer and 5-10 parts of water. Preferably, the particle size of the fly ash is 1-20 microns. Preferably, the recycled coarse aggregate is a class I recycled coarse aggregate. Preferably, the melting point of the polyethylene terephthalate is 250-260 ℃. Preferably, the polyoxymethylene is a polyoxymethylene homopolymer, and the melting point of the polyoxymethylene is 175-185 ℃. Preferably, the fine aggregate is river sand, and the fineness modulus of the fine aggregate is 2.6-3. Preferably, the water reducer is a polycarboxylic acid high-performance water reducer. The invention also provides a preparation method of the recycled concrete composite material, which is characterized by comprising the following steps: (1) Mixing the recycled coarse aggregate, polyethylene terephthalate and polyoxymethylene, and sequentially heating, heat treating and cooling to obtain modified aggregate; (2) And mixing the modified aggregate with cement, fly ash, fine aggregate, a water reducing agent and water to obtain the recycled concrete composite material. Preferably, the temperature rising rate of the temperature rising is 20-25 ℃ per minute, the temperature of the heat treatment is 260-270 ℃, the heat preservation time is 30-50 minutes, and the cooling rate is 5-10 ℃ per minute. The invention also provides application of the recycled concrete composite material in the field of road engineering, wherein the recycled concrete composite material is the recycled concrete composite material according to the scheme or the recycled concrete composite material obtained by the preparation method according to the scheme. The invention provides a recycled concrete composite material. The recycled concrete composite material provided by the invention realizes that the recycled concrete composite material with high strength is obtained under the premise of ensuring the replacement rate of recycled aggregate through the synergistic effect of the components, has low cost, realizes the dual purposes of economic benefit and performance enhancement, and has wide application prospect. The invention also provides a preparation method of the recycled concrete composite material, and the recycled concrete composite material is prepared by the scheme. The preparation method provided by the invention has the advantages of low cost, simple steps, convenient operation, no dependence on large-scale equipment and potential of industrialization scale